The imagery and scientific data collection by these robotic explorers has inspired generations and forever altered how we view our planet and the universe around us. As a result, spacecraft such as the James Webb Space Telescope (JWST) and the venerable Voyager 1 probe are now household names, but how many of us actually know where they are as they beam back their precious data? How many of us have peered into the areas of space where they orbit or sail through the cosmos?

Read on to discover the approximate locations of five far-flung spacecraft in the October night sky. If you're new to exploring the stars, be sure to check out our roundup of the best smartphone astronomy apps, which use augmented reality tech to help guide you to the locations of everything from stars and nebulas to galaxies, wandering comets and spacecraft.

Find the locations of famous spacecraft in the October night sky

James Webb Space Telescope — 907,000 miles (1.46 million km) from Earth

The James Webb Space Telescope launched on Christmas Day in 2021 on a mission to unravel the mysteries surrounding the creation and evolution of the cosmos. From its gravitationally stable vantage point at Lagrange Point 2, the JWST is tasked with peering into deep space to capture ancient light from the early universe and observe the formation of stars, protoplanetary systems and so much more. Check out our article detailing 12 amazing JWST discoveries to find out how the most powerful telescope ever launched is pushing the boundaries of astronomy.

To find the JWST's position in the night sky, you'll first need to locate the red star Aldebaran, which can be found half way up the eastern sky above the familiar stars of the constellation Orion around midnight in October. Next, scan the region above until you find the diffuse, hazy light of the Pleiades star cluster. Webb will be located approximately 5 degrees — roughly the width of your three middle fingers held at arm's length against the night sky — below the Pleiades and will travel closer to Aldebaran and the other stars of the constellation Taurus as the month wears on.

Remember: this guide can show you the approximate location of the spacecraft, but it is impossible to actually spot them, as they are far too small and distant for even the most powerful of telescopes to resolve.

Parker Solar Probe — 91 million miles (147.6 million km) from Earth

NASA's Parker Solar Probe became the first spacecraft to "touch" the sun on April 28, 2021, when it careened through the sun's outer atmosphere — also known as the corona — during the eighth of 24 planned close passes of our parent star. The probe has flown seven times closer to the sun than any spacecraft before while braving temperatures approaching 2,600 degrees Fahrenheit (1,300 degrees Celsius) to shed light on the plasma and magnetic field dynamics that drive the solar wind.

The patch of sky containing the Parker Solar Probe can be found low in the southwestern sky at sunset in October, though you'll need a clear view of the horizon to spot it before it sets out of view! First, find the bright star Antares in the constellation Scorpius. The Parker Solar Probe's location is roughly 5 degrees to the upper left of the red supergiant star, with the constellation Ophiuchus shining above and the distinctive "teapot" asterism of the constellation Sagittarius to its left.

NASA's Juno spacecraft — 464.8 million miles (748 million km) from Earth

The Juno spacecraft reached orbit around Jupiter in 2016 and has spent close to a decade — and several mission extensions — collecting data on both the gas giant and its many diverse moons. Its most recent mission extension expired on the same day that the current government shutdown came into effect. As a result, an ominous question mark hangs over the fate of the veteran spacecraft.

To find Juno's location, you'll first need to locate the bright stars Castor and Pollux in the constellation Gemini, which twinkles high overhead in the eastern sky during the predawn hours in October. Jupiter will be easy to find as a bright "morning star" shining steadily to the lower right of Castor and Pollux. Juno is somewhere in orbit around the planet, far too small to be seen.

New Horizons — 5.88 billion miles (9.46 billion km) from Earth

NASA's New Horizons spacecraft launched in January 2006 and after nine years travelling in space became the first human-made object to visit the dwarf planet Pluto in July 2015. The short-lived flyby transformed our understanding of the far-flung world, revealing surprising aspects of its composition, tenuous atmosphere and the nature of its largest moon, Charon. New Horizons later went on to study the Kuiper Belt object Arrokoth in 2019 and is now working to gather heliophysics data while enroute to interstellar space, which it is expected to reach sometime in the 2040s.

The patch of night sky containing New Horizons can be found by locating the famous "teapot" asterism at the heart of the constellation Sagittarius above the southern horizon in the hours following sunset in October. From a dark sky location, you may see the glowing band of the Milky Way extending overhead and running through the "spout" of the stellar teapot!

Next, look above the trapezium of stars that form the handle of the asterism and locate the star Pi Sagittarii using your smartphone astronomy app. New Horizons' location is roughly 1 degree to the upper right of this little-known star.

Voyager 1 — 15.72 billion miles (25 billion km) from Earth

Voyager 1 is the most distant human-made object ever launched and became the first spacecraft to enter interstellar space when it passed beyond the heliosphere (a giant bubble in our solar system created by the solar wind that protects the planets from cosmic rays) in August 2012, following a tour of Jupiter and Saturn. The spacecraft carries with it one of NASA's famous Golden Records, which contain a selection of greetings, images and sounds from Earth curated as both a time capsule and a method of establishing friendly first contact with any who may later find the distant probe.

Voyager 1's location in the night sky can be found by first locating the stars of the constellation Ophiuchus close to the western horizon in the hours following sunset in October. Next, locate the highest point of light in the constellation — the binary star system Rasalhague — and its neighbor Kappa Ophiuchi to the lower right. Voyager 1's approximate position lies half way along the imaginary line connecting these two stellar giants.

Editor's Note: If you would like to share your astrophotography with Space.com's readers, then please send your photo(s), comments, and your name and location to spacephotos@space.com.

The declaration, organized by Stand Up For Science, criticizes steep budget cuts, the cancellation of missions in development, terminated contracts and grants, and organizational changes that undermine NASA's ability to conduct critical space and Earth science research. One major concern is the weakening of NASA's Technical Authority — a vital internal safety oversight system created after the 2003 Columbia shuttle disaster to prevent avoidable accidents, according to the declaration.

In the Voyager Declaration, the 287 signatories warn that political interference and abrupt budget reductions could jeopardize decades of progress in space exploration, aeronautics and climate science. They argue that the Trump administration's efforts to slash NASA's science funding — which includes cutting more than $120 million in grants and proposing nearly a 50% reduction to the agency's Science Mission Directorate budget by 2026 — undermines Congress-approved priorities and threatens the agency's mission.

The declaration, issued on Monday (July 21), also highlights the loss of thousands of civil servant positions and a growing "culture of organizational silence," where employees feel unable to voice concerns without retaliation — which is also why over 150 signatories opted to remain anonymous. This atmosphere, they argue, poses risks not only to scientific discovery but also to astronaut safety and mission success.

Stand Up For Science, a nonprofit advocacy group founded in 2025, has made the full declaration public and opened a petition inviting others to support the agency's employees in their stand for science and safety. The petition emphasizes that NASA's work is a public good that cannot be replaced by private companies and calls on leadership to resist political pressure.

This statement from NASA personnel marks one of the most significant acts of internal dissent in recent years, underscoring the importance of protecting science from political influence. The declaration, list of named signatories and more information can be found online.

Now "The Blue Danube" waltz with its whirling orbital rhythms will truly become the music of the cosmos when the European Space Agency broadcasts the lilting classical piece into deep space in celebration of the agency's 50th anniversary this year, in addition to the bicentennial of Johann Strauss II's birth in 1825.

Performed by the Wiener Symphoniker (Vienna Symphony Orchestra), this definitive anthem of space and sci-fi will be transmitted towards NASA's Voyager 1 probe by ESA's 35-meter Deep Space Antenna in Cebreros, Spain. Space fans and music lovers can watch an entire 15-minute livestream on the event's official website and on their YouTube or Instagram Channel regardless of your location, starting at 3:30 p.m. ET (1930 GMT) on Saturday (May 31).

Known in its native German as "An der schönen blauen Donau" which translates into "By the Beautiful Blue Danube," the sublime composition's 13,743 notes are being broadcast into the interstellar void on a mission that "is both a tribute to the past and a testament to the future – a Viennese Waltz that will echo through space forever," according to the event's website.

Composed by Strauss in 1866 as a consolatory gift to the Viennese people after defeat in the Austro-Prussian War, "The Blue Danube" was conceived from a poem describing the Danube River by Karl Isidor Beck that contained the phrase "beautiful blue Danube."

It's one of the most widely recognized pieces of classical music in the world, partly due to its Hollywood history, its associations with space, and being a universally-loved audience favorite in concert halls around the globe.

In a pivotal transition scene from director Stanley Kubrick's magnum opus "2001: A Space Odyssey," the film cuts from a twirling bone during the dawn of early humans to an orbiting nuclear weapons platform in the future as the camera follows a needle-nosed Pan Am spaceship drifting towards a gently turning space station. The tune continues on as another shuttle docks at the Clavius moonbase built on the lunar surface.

Fans also might recall "The Blue Danube Waltz" being employed in an episode of "The Simpsons" where Homer opens a smuggled bag of potato chips ("Careful, they're ruffled!") inside a space shuttle and proceeds to catch floating chips in his mouth along to the swaying melody of the Strauss melody.

The King of Waltz's iconic musical masterpiece wasn't included in NASA's Voyager space probes' Golden Records launched into space back in 1977, but this Waltz into Space aimed at Voyager 1 will correct that glaring oversight.

Currently, Voyager 1 is traveling 15.4 billion miles (24.8 billion kilometers) from Earth, taking this celebratory signal roughly 23 hours and 3 minutes to reach the historic spacecraft.

This rare event lasted about an hour on April 7 and was only visible from western North America. The last time a bright stellar occultation of Uranus occurred was 1996, so NASA came prepared. An international team of more than 30 astronomers, led by planetary scientists at NASA's Langley Research Center in Virginia, used 18 observatories to gather data.

"This was the first time we have collaborated on this scale for an occultation," William Saunders, a planetary scientist at Langley, said in a statement.

"I am extremely grateful to each member of the team and each observatory for taking part in this extraordinary event," Saunders added. "By observing the occultation from many large telescopes, we are able to measure the light curve and determine Uranus' atmospheric properties at many altitude layers."

Related: Uranus: Everything you need to know about the coldest planet in the solar system

For example, the scientists measured the temperatures and composition of Uranus' stratosphere, the middle layer of its atmosphere. They were able to see how the stratosphere has changed since 1996, when NASA got a snapshot of Uranus' atmosphere during the last significant stellar occultation.

The data NASA just collected "could help enable future Uranus exploration efforts," agency officials said in the statement.

Uranus, which is currently about 2 billion miles (3.2 billion kilometers) from Earth, does not have a solid surface. Instead, the planet has a soft surface that's a mixture of water, ammonia and methane. Researchers call Uranus an ice giant because its interior consists largely of these fluids, all of which have low freezing points. The planet's atmosphere is mostly made up of hydrogen and helium.

"The atmospheres of the gas and ice giant planets [Jupiter, Saturn, Uranus and Neptune] are exceptional atmospheric laboratories because they don't have solid surfaces," Emma Dahl, a postdoctoral scholar at the California Institute of Technology who assisted in gathering observations from NASA's Infrared Telescope Facility in Hawaii, said in the same statement.

"This allows us to study cloud formation, storms and wind patterns without the extra variables and effects a surface produces, which can complicate simulations very quickly," she added.

NASA says Uranus will occult several dimmer stars over the next six years. The next significant Uranus occultation, which will involve a star even brighter than the one blocked out this month, will come in 2031.

Also on March 19, the agency began work on a new member of this facility: Deep Space Station 33. This will be the fifth radio antenna for Canberra; there are two other Deep Space Network facilities, one in Barstow, California and the other in Madrid, Spain.

"When it goes online in 2029, the new Canberra dish will be the last of six parabolic dishes constructed under NASA's Deep Space Network Aperture Enhancement Program," agency officials wrote in a statement, "which is helping to support current and future spacecraft and the increased volume of data they provide."

NASA's Deep Space Network (DSN) is pretty spectacular in both a big-picture and small-scale sense.

Related: NASA's Deep Space Network: How spacecraft phone home

To transmit communications throughout the solar system, the three DSN facilities are strategically placed around the globe so one can pick up when another may need to leave off. Due to Earth's rotation, and the typically multiyear length of space missions, this switch happens quite often.

The new dish, Deep Space Station 33, will be a 112-foot-wide (34 meters) multifrequency beam-waveguide antenna (BWG), according to the NASA statement. This sort of antenna has five mirrors that reflect radio signals coming from space along what's known as a "beam waveguide tube" to a concrete pedestal buried mostly underground. There, the signal gets translated into information that scientists can interpret.

According to NASA, Canberra is the only complex that can fully speak to the iconic Voyager 2 spacecraft that's about 13 billion miles (20.9 billion kilometers) away from us — and getting farther as you read this. Voyager 1 can send its information to the other two facilities, but even it can only can receive commands from Canberra.

Despite being built decades ago, the Voyagers are still considered some of the most brilliant feats of human engineering to date. Surely, having a new dish at Canberra is bound to enable the next generation of awe-inspiring instruments. Even with the 0's and 1's of spacecraft, language is everything.

Chop Shop on Tuesday (April 8) began seeking fans of robotic satellites and interplanetary spacecraft to help them create a series of hard enamel lapel pins. In addition to seeking pledges through a crowdfunding campaign, the Philadelphia-based store is turning to the public to pick out the probe for the fifth pin in the line.

"Each of these missions represents the best of what human intellect can achieve — and for many, they also carry a strong sense of nostalgia," reads Chop Shop's campaign description on the BackerKit website.

The featured missions were selected through a poll conducted by The Planetary Society, with the top results being the Voyager "Grand Tour" program of the 1970s and 1980s; the Cassini/Huygens mission to Saturn and its moon Titan; Mars Science Laboratory (the Curiosity and Perseverance rovers); and Earth's first-ever artificial satellite, the Soviet-era Sputnik.

Related: Sputnik: The space race's opening shot

Chop Shop is basing the pins' designs on a popular collection of posters they produced in 2014 and 2015. The Historic Robotic Spacecraft Series has since inspired the production of decals, toy blocks, patches, t-shirts and glassware.

"As of now, only the Voyager enamel pin has been produced. While the rest of the missions already exist as part of our original poster series, they've not yet been translated into enamel pins — but they're ready to go," the company's reps wrote.

The pins will be made of hard enamel with a silver line structure. Measurements of each pin will vary slightly due to their shape, but they have been designed to appear as a set. Individual pins will cost $8.50 each, while a full set of five mission is $40. A $24 trio of the first three designs — Voyager, Cassini and Mars Science — is also being offered.

"Voyager was a defining part of the '80s, with its grand tour of the outer planets and its tie-in to Carl Sagan's 'Cosmos.' In the '90s, Galileo gave us a dramatic look at Jupiter and its moons. Then in the 2000s, Cassini arrived at Saturn, and two remarkably durable rovers landed on Mars," reads the Chop Shop description.

For the fifth pin, Chop Shop has invited the public to vote on nine different choices, ranging from NASA's Messenger mission to orbit Mercury to the New Horizons probe that flew past Pluto. Other choices include the Soviet-era Venera probes that touched down on Venus; the Viking landers and Mars Exploration Rovers Spirit and Opportunity; the Galileo and Juno missions to Jupiter; the European Space Agency's Rosetta and Philae spacecraft that studied a comet; and the now interstellar Pioneer 10 and 11 probes.

Voting is open through April 14, while BackerKit pledges close on April 28 at 9:00 p.m. EDT (0100 GMT on April 29). The campaign exceeded its $1,000 goal within hours of first being offered on Tuesday (April 8) from the support of more than 25 backers.

Chop Shop expects to begin shipping the Historic Robotic Spacecraft Series pins in early June.

Follow collectSPACE.com on Facebook and on X at @collectSPACE. Copyright 2025 collectSPACE.com. All rights reserved.

Voyager 2 launched into space on Aug. 20, 1977 and left the solar system on Nov. 5, 2018. It is currently 12.8 billion miles (20.5 billion kilometers) from Earth and is using four science instruments to study space beyond the heliosphere, the sun's bubble of influence around the solar system. NASA thinks that Voyager 2 has enough power to keep running one science instrument into the 2030s, but doing that requires selecting which of its other instruments need to be turned off. 

Mission specialists have tried to delay the instrument shutdown until now because Voyager 2 and Voyager 1 are the only two active probes humanity has in interstellar space, making any data they gather unique. Thus far, six of the spacecraft's initial 10 instruments have been deactivated. Now, losing the seventh has become unavoidable, and the spacecraft's plasma science instrument drew the short straw. On Sept. 26, engineers gave the command to turn off the instrument.

The plasma science instrument consists of four "cups" collecting information on the amount of plasma, a fluid of charged particles, flowing past Voyager 2 and the direction of this flow. Three cups are angled toward the sun, monitoring charged particles in the solar wind while within the heliosphere. A fourth cup is angled away from the others to observe plasma in planetary magnetic fields and interstellar space.

Related: Voyager 1 is back online! NASA's most distant spacecraft returns data

This instrument was crucial in detecting the drop-off in charged particles from the sun, which indicated that Voyager 2 had crossed the boundary between the heliosphere and interstellar space in 2018. 

"Mission engineers always carefully monitor changes being made to the 47-year-old spacecraft's operations to ensure they don't generate any unwanted secondary effects," officials at NASA's Jet Propulsion Laboratory, which oversees the mission, wrote in a statement. "The team has confirmed that the switch-off command was executed without incident and the probe is operating normally."

The usefulness of the plasma science instrument was limited by the fact that the three cups angled toward the sun stopped collecting plasma after leaving the heliosphere and moving past the influence of solar wind. 

Also, because of Voyager 2's orientation, the data it has harvested over the last few years has been further limited. The one active cup only provides useful data once every three months when the spacecraft makes a 360-degree turn on its axis. This influenced the decision to switch the plasma instrument off to conserve power rather than deactivating one of Voyager 2's other instruments.

Both Voyager 1 and Voyager 2 are powered by decaying plutonium, and they lose around 4 watts of power every year. In the 1980s, several of their instruments were turned off after the two spacecraft finished investigating the solar system's giant planets. This granted both probes extra power, boosting their longevity.

A few years ago, the two crafts also turned off all non-essential instruments. Voyager 1's plasma instrument stopped working in 1980, and it was switched off in 2007 to preserve power. 

Meanwhile, NASA engineers are closely watching the resources of Voyager 2 so they can decide when its next science instrument must be depowered to ensure the interstellar explorer can deliver science for as long as possible from this "final frontier" beyond the solar system.

Humanity has lost an interstellar pioneer.

Ed Stone, who served as the project scientist for NASA's groundbreaking Voyager mission from 1972 to 2022, died on Sunday (June 9) at the age of 88.

"Ed Stone was a trailblazer who dared mighty things in space. He was a dear friend to all who knew him, and a cherished mentor to me personally," Nicola Fox, associate administrator for the Science Mission Directorate at NASA Headquarters in Washington, said in NASA's obituary for Stone, which the agency posted on Tuesday (June 11). 

"Ed took humanity on a planetary tour of our solar system and beyond, sending NASA where no spacecraft had gone before," Fox added. "His legacy has left a tremendous and profound impact on NASA, the scientific community, and the world. My condolences to his family and everyone who loved him. Thank you, Ed, for everything."

Related: Going interstellar: Q&A with Voyager project scientist Ed Stone

Voyager launched twin probes on a "grand tour" of the solar system's giant planets in 1977. The two spacecraft made many discoveries in our cosmic backyard — finding intense volcanism on the Jupiter moon Io and 10 new moons of Uranus, for example — and then kept on flying, into exciting and unexplored realms.

In 2012, Voyager 1 popped free of the heliosphere, the huge bubble of charged particles and magnetic fields that the sun blows around itself, becoming the first human-made object ever to reach interstellar space. Voyager 2, which took a different path and is moving slightly more slowly than its partner, followed suit in late 2018.

Both Voyagers remain operational today, studying the exotic environment between our star and the next. Voyager 1 is currently more than 15 billion miles (24 billion kilometers) from home, and its twin is about 13 billion miles (21 billion km) into the void. That's about 162 and 136 Earth-sun distances (or astronomical units), respectively.

"It has been an honor and a joy to serve as the Voyager project scientist for 50 years," Stone said in a NASA statement in October 2022, when he announced his retirement from the role.

"The spacecraft have succeeded beyond expectation, and I have cherished the opportunity to work with so many talented and dedicated people on this mission," he added. "It has been a remarkable journey, and I'm thankful to everyone around the world who has followed Voyager and joined us on this adventure."

Related: Voyager: 15 incredible images of our solar system (gallery)

Stone was born on Jan. 23, 1936, in Knoxville, Iowa, according to NASA's obituary. His father was a construction superintendent who loved showing his son how to take things apart and put them back together — and young Ed was an eager student.

"I was always interested in learning about why something is this way and not that way," Stone said in an interview in 2018, according to NASA's obituary. "I wanted to understand and measure and observe."

He studied physics in junior college, then went to the University of Chicago for graduate school, where he helped build science instruments for spacecraft — still a very young field at this stage.

"The first he designed rode aboard Discoverer 36, a since-declassified spy satellite that launched in 1961 and took photographs of Earth from space as part of the Corona program," NASA wrote in the obituary. "Stone's instrument, which measured the sun's energetic particles, helped scientists figure out why solar radiation was fogging the film and ultimately improved their understanding of the Van Allen belts, energetic particles trapped in Earth's magnetic field."

Stone became a post-doctoral fellow at the California Institute of Technology (Caltech) in 1964 and soon began working on NASA missions. Over the years, he served as the principal investigator or a science instrument lead on nine different agency missions and a co-investigator on five others, according to the agency. 

Stone also served as director of the Jet Propulsion Laboratory (JPL) in Southern California — the agency's lead center for robotic planetary exploration — from 1991 to 2001. That stretch saw some major milestones, including the landing of NASA's first-ever Mars rover, Sojourner, in 1996 with the Pathfinder mission and the launch of the Cassini-Huygens mission to Saturn (a joint effort with the European Space Agency) in 1997.

"Ed will be remembered as an energetic leader and scientist who expanded our knowledge about the universe — from the sun to the planets to distant stars — and sparked our collective imaginations about the mysteries and wonders of deep space," JPL Director Laurie Leshin, who's also the vice president of Caltech, said in NASA's obituary.

"Ed’s discoveries have fueled exploration of previously unseen corners of our solar system and will inspire future generations to reach new frontiers," Leshin added. "He will be greatly missed and always remembered by the NASA, JPL and Caltech communities and beyond."

Stone's colleagues have repeatedly noted his commitment to science education and communication, his genuine desire to help tell the world about scientific results in a manner both accurate and engaging.

I can attest to this commitment, for I witnessed it first-hand on multiple occasions. Despite being a very busy man, Stone was open and available to the media; he took our phone calls and stayed on after press conferences to answer more and more of our questions.

And he was unfailingly nice, polite and patient in all of these interactions. I didn't know Ed Stone well, but I could tell he was a good man. And I, like countless others, will miss him.

"NASA's Voyager 1 interstellar spacecraft actually isn't even in the solar system anymore," I announced. "Nope, it's more than 15 billion miles (24 billion km) away from us — and it's getting even farther as we speak." I can't quite remember his response, but I do indeed recall an expression of sheer disbelief. There were immediate inquiries about how that's even physically possible. There were bewildered laughs, different ways of saying "wow," and mostly, there was a contagious sense of awe. And just like that, a new Voyager 1 fan was born.

It is easy to see why Voyager 1 is among the most beloved robotic space explorers we have — and it is thus easy to understand why so many people felt a pang to their hearts several months ago, when Voyager 1 stopped talking to us.

Related: NASA's Voyager 1 spacecraft finally phones home after 5 months of no contact

For reasons unknown at the time, this spacecraft began sending back gibberish in place of the neatly organized and data-rich 0's and 1's it had been providing since its launch in 1977. It was this classic computer language which allowed Voyager 1 to converse with its creators while earning the title of "farthest human made object." It's how the spacecraft relayed vital insight that led to the discovery of new Jovian moons and, thanks to this sort of binary podcast, scientists incredibly identified a new ring of Saturn and created the solar system's first and only "family portrait." This code, in essence, is crucial to Voyager 1's very being.

Plus, to make matters worse, the issue behind the glitch turned out to be associated with the craft's Flight Data System, which is literally the system that transmits information about Voyager 1's health so scientists can correct any issues that arise. Issues like this one. Furthermore, because of the spacecraft's immense distance from its operators on Earth, it takes about 22.5 hours for a transmission to reach the spacecraft, and then 22.5 hours to receive a transmission back. Alas, things weren't looking good for a while — for about five months, to be precise.

But then, on April 20, Voyager 1 finally phoned home with legible 0's and legible 1's.

"The team had gathered early on a weekend morning to see whether telemetry would return," Bob Rasmussen, a member of the Voyager flight team, told Space.com. "It was nice to have everyone assembled in one place like this to share in the moment of learning that our efforts had been successful. Our cheer was both for the intrepid spacecraft and for the comradery that enabled its recovery."

And then, on May 22, Voyager scientists released the welcome announcement that the spacecraft has successfully resumed returning science data from two of its four instruments, the plasma wave subsystem and magnetometer instrument. They're now working on getting the other two, the cosmic ray subsystem and low energy charged particle instrument, back online as well. Though there technically are six other instruments onboard Voyager, those had been out of commission for some time.

The comeback

Rasmussen was actually a member of the Voyager team in the 1970s, having worked on the project as a computer engineer before leaving for other missions including Cassini, which launched the spacecraft that taught us almost everything we currently know about Saturn. In 2022, however, he returned to Voyager because of a separate dilemma with the mission — and has remained on the team ever since.

"There are many of the original people who were there when Voyager launched, or even before, who were part of both the flight team and the science team," Linda Spilker, a planetary scientist at NASA's Jet Propulsion Laboratory, who also worked on the Voyager mission, told Space.com in the This Week from Space podcast on the TWiT network. "It's a real tribute to Voyager — the longevity not only of the spacecraft, but of the people on the team."

To get Voyager 1 back online, in rather cinematic fashion, the team devised a complex workaround that prompted the FDS to send a copy of its memory back to Earth. Within that memory readout, operators managed to discover the crux of the problem — a corrupted code spanning a single chip — which was then remedied through another (honestly, super interesting) process to modify the code. On the day Voyager 1 finally spoke again, "you could have heard a pin drop in the room," Spilker said. "It was very silent. Everybody's looking at the screen, waiting and watching." 

Of course, Spilker also brought in some peanuts for the team to munch on — but not just any peanuts. Lucky peanuts. 

It's a longstanding tradition at JPL to have a peanut feast before major mission events like launches, milestones and, well, the possible resurrection of Voyager 1. It began in the 1960s, when the agency was trying to launch the Ranger 7 mission that was meant to take pictures of and collect data about the moon's surface. Rangers 1 through 6 had all failed, so Ranger 7 was a big deal. As such, the mission's trajectory engineer, Dick Wallace, brought lots of peanuts for the team to nibble on and relax. Sure enough, Ranger 7 was a success and, as Wallace once said, "the rest is history." 

Voyager 1 needed some of those positive snacky vibes. 

"It'd been five months since we'd had any information," Spilker explained. So, in this room of silence besides peanut-eating-noises, Voyager 1 operators sat at their respective system screens, waiting. 

"All of a sudden it started to populate — the data," Spilker said. That's when the programmers who had been staring at those screens in anticipation leapt out of their seats and began to cheer: "They were the happiest people in the room, I think, and there was just a sense of joy that we had Voyager 1 back."

Eventually, Rasmussen says the team was able to conclude that the failure probably occurred due to a combination of aging and radiation damage by which energetic particles in space bombarded the craft. This is also why he believes it wouldn't be terribly surprising to see a similar failure occur in the future, seeing as Voyager 1 is still roaming beyond the distant boundaries of our stellar neighborhood just like its spacecraft twin, Voyager 2.

To be sure, the spacecraft isn't fully fixed yet — but it's lovely to know things are finally looking up, especially with the recent news that some of its science instruments are back on track. And, at the very least, Rasmussen assures that nothing the team has learned so far has been alarming. "We're confident that we understand the problem well," he said, "and we remain optimistic about getting everything back to normal — but we also expect this won't be the last."

In fact, as Rasmussen explains, Voyager 1 operators first became optimistic about the situation just after the root cause of the glitch had been determined with certainty. He also emphasizes that the team's spirits were never down. "We knew from indirect evidence that we had a spacecraft that was mostly healthy," he said. "Saying goodbye was not on our minds."

"Rather," he continued, "we wanted to push toward a solution as quickly as possible so other matters on board that had been neglected for months could be addressed. We're now calmly moving toward that goal."

The future of Voyager's voyage

It can't be ignored that, over the last few months, there has been an air of anxiety and fear across the public sphere that Voyager 1 was slowly moving toward sending us its final 0 and final 1. Headlines all over the internet, one written by myself included, have carried clear, negative weight. I think it's because even if Voyager 2 could technically carry the interstellar torch post-Voyager 1, the prospect of losing Voyager 1 felt like the prospect of losing a piece of history. 

"We've crossed this boundary called the heliopause," Spilker explained of the Voyagers. "Voyager 1 crossed this boundary in 2012; Voyager 2 crossed it in 2018 — and, since that time, were the first spacecraft ever to make direct measurements of the interstellar medium." That medium basically refers to material that fills the space between stars. In this case, that's the space between other stars and our sun, which, though we don't always think of it as one, is simply another star in the universe. A drop in the cosmic ocean.

"JPL started building the two Voyager spacecraft in 1972," Spilker explained. "For context, that was only three years after we had the first human walk on the moon — and the reason we started that early is that we had this rare alignment of the planets that happens once every 176 years." It was this alignment that could promise the spacecraft checkpoints across the solar system, including at Jupiter, Saturn, Uranus and Neptune. Those checkpoints were important for the Voyagers in particular. Alongside planetary visits come gravity assists, and gravity assists can help fling stuff within the solar system — and, now we know, beyond.

As the first humanmade object to leave the solar system, as a relic of America's early space program, and as a testament to how robust even decades-old technology can be, Voyager 1 has carved out the kind of legacy usually reserved for remarkable things lost to time.

"Our scientists are eager to see what they’ve been missing," Rasmussen remarked. "Everyone on the team is self-motivated by their commitment to this unique and important project. That's where the real pressure comes from." 

Still, in terms of energy, the team's approach has been clinical and determined. 

"No one was ever especially excited or depressed," he said. "We're confident that we can get back to business as usual soon, but we also know that we're dealing with an aging spacecraft that is bound to have trouble again in the future. That's just a fact of life on this mission, so not worth getting worked up about."

Nonetheless, I imagine it's always a delight for Voyager 1's engineers to remember this robotic explorer occupies curious minds around the globe. (Including my dad's mind now, thanks to me and Google.)

As Rasmussen puts it: "It's wonderful to know how much the world appreciates this mission."

The glitch caused Voyager 1 to send unreadable data back to Earth, and is found in the NASA spacecraft's flight data subsystem (FDS). That's the system responsible for packaging the probe's science and engineering data before the telemetry modulation unit (TMU) and radio transmitter send it back to mission control. 

The source of the issue began to reveal itself when Voyager 1 operators sent the spacecraft a "poke" on March 3, 2024. This was intended to prompt FDS to send a full memory readout back to Earth.

The readout confirmed to the NASA team that about 3% of the FDS memory had been corrupted, and that this was preventing the computer from carrying out its normal operations.

Related: NASA finds clue while solving Voyager 1's communication breakdown case

Launched in 1977, Voyager 1 became the first human-made object to leave the solar system and enter interstellar space in 2012. Voyager 2 followed its spacecraft sibling out of the solar system in 2018, and is still operational and communicating well with Earth.

After 11 years of interstellar exploration, in Nov. 2023, Voyager 1's binary code — the computer language it uses to communicate with Earth — stopped making sense. Its 0's and 1's didn't mean anything anymore.

"Effectively, the call between the spacecraft and the Earth was still connected, but Voyager's 'voice' was replaced with a monotonous dial tone," Voyager 1's engineering team previously told Space.com.

The team strongly suspects this glitch is the result of a single chip that's responsible for storing part of the affected portion of the FDS memory ceasing to work.

Currently, however, NASA can’t say for sure what exactly caused that particular issue. The chip could have been struck by a high-speed energetic particle from space or, after 46 years serving Voyager 1, it may simply have worn out.

Voyager 1 currently sits around 15 billion miles (24 billion kilometers) from Earth, which means it takes 22.5 hours to receive a radio signal from it — and another 22.5 hours for the spacecraft to receive a response via the Deep Space Network's antennas. Solving this communication issue is thus no mean feat.

Yet, NASA scientists and engineers are optimistic they can find a way to help FDS operate normally, even without the unusable memory hardware.

Solving this issue could take weeks or even months, according to NASA — but if it is resolved, Voyager 1 should be able to resume returning science data about what lies outside the solar system.

"Sad and frustrated to have the spacecraft still working, but muted," Bruce Waggoner, the Voyager mission assurance manager, told Space.com of the group's present morale. "Even though we know the end could come at any time, it's never easy to lose a spacecraft. Especially one like Voyager 1."

For more than 45 years, this boxy machine with a pearly white, conical disk that sort of makes it look like a giant loudspeaker in space has been sending back stunning data. And I mean stunning. Not only is it the first craft to enter interstellar space (and therefore the farthest human-made object ever), but it's also responsible for the identification of new Jovian moons, the discovery of yet another Saturnian ring and the solar system's first and only "family portrait" that includes our eclectic gang of planets.

Related: NASA's interstellar Voyager 1 spacecraft isn't doing so well — here's what we know

It's also why we have the powerful Pale Blue Dot image that resurfaces on the internet every so often to remind us of our insignificance, or rather, significance, depending on your perspective. As Carl Sagan famously said, "Look again at that dot. That's here. That's home. That's us."

All this time, Voyager 1's cosmic letters have come through as computer messages often do, with 0's and 1's in precise patterns. Through a little bit of handiwork, such sequences can be translated into words the human mind can grasp — and scientists were always excited to open a new package of Voyager 1's binary code. 

But then, in September of last year, the 0's and 1's stopped making sense. 

"Effectively, the call between the spacecraft and the Earth was still connected, but Voyager's 'voice' was replaced with a monotonous dial tone," the engineering team told Space.com.

Glitches have happened to Voyager 1 before, such as in 2022 when the probe's "attitude articulation and control system" exhibited some complications, but this one seems to be a doozy. The team still hasn't been able to fix it up, even months since the issue revealed itself, and is actually still searching for the crux of the problem.

So, is it time to call the final curtain on Voyager 1? 

Well, to that end, scientists aren't quite sure yet. They remain working to remedy the situation — and quite diligently at that. "The team is tired because we have sustained a brisk pace for 3 months now, but we press on because we have ideas, and we have hope," Voyager mission engineer Kareem Badaruddin told Space.com.

 However, what the team is sure of is that even if Voyager 1 succumbs to its wounds, the voyage is certainly not over.

"Don't forget Voyager 2 is still going strong! If we can keep one spacecraft going, the mission will continue," the crew said.

Voyager 2, which looks an awful lot like Voyager 1, actually launched 16 days before its counterpart, on Aug. 20, 1977. Voyager 1 just happened to get farther faster because it had a more efficient route out of the asteroid belt, officially overtaking its partner on Dec. 15, 1977 and later becoming the first probe to exit the gravitational influence of our solar system. Voyager 2 does have a bunch of achievements under its own belt, though, such as the fact that it's still the only spacecraft to have visited the outer planets, Uranus and Neptune. 

Together, the Voyagers' joint mission was to simply explore — to plunge through the solar system, sweep across moons and planets beyond our own and try to go where no spacecraft has gone before.

"The Voyagers are the only spacecraft exploring interstellar space in-situ, and there are no missions that can gather this same data remotely," the team said.

They've surely been doing their duty, and hopefully, Voyager 1 has a little more juice left. But even if it doesn't, scientists wish to make clear that Voyager 2 shall continue to keep the torch lit.

Voyager 1's medical chart 

In December of 2023, the Voyager 1 team announced that the spacecraft's malfunction lies with its Flight Data System, or FDS, which is one of its onboard computers. There used to be a backup FDS, but that stopped working in 1981. 

"Because of this issue, scientists are not receiving any science data or updates about the probe's health and status, including information that might reveal the source of the problem," the team explains.

Here's where perhaps the greatest trouble with this dilemma comes in. One of the FDS' main jobs is to basically keep Voyager 1's medical records up to date, then work with what's known as the telemetry modulation unit, or TMU, to tell ground control what's going on. But, because the FDS itself is the one malfunctioning, that medical record transmission can't happen.

"The team has attempted various 'simple' fixes, such as resetting the FDS to the state it was in before the issue began," the engineers said. "This week, the team will send more commands to the spacecraft to gather information about the status of the onboard systems. In the coming weeks, the team expects to start making more aggressive attempts to reset various systems that might influence the FDS."

As of now, the team believes one possible cause of the issue has to do with the FDS' memory being corrupted by some mechanism that leads its binary code to sprout unintelligible patterns. However, engineers are also considering the fact that it could be a physical hardware failure. After all, Voyager 1's mechanics have been toiling away for multiple decades. Something could've simply broken down, hardware- or software-wise. In fact, scientists beamed some preemptive software patches to both of the Voyagers last year, from billions of miles away.

"The anomaly has caused us to study and learn about the spacecraft — much knowledge that was forgotten because it wasn't needed for many years has been recovered," Badaruddin said.

In a slightly more far-fetched scenario, the team also suggests it's possible some sort of energetic particle could've smashed into the spacecraft. If that happened, it might've created what's known as a "bit flip," which means a 0 in the code accidentally became a 1, or vice versa.

Still, the team is leaving all possibilities open. That's because, in truth, it might not even be the FDS that's causing problems in the first place. This theory is just the most likely one to stem from data the engineers currently have. "Because no engineering data is coming back, it's very hard to isolate the source of the problem" they said.

Moreover, in a bit of a non-silver lining, remember how Voyager 1's greatest achievement is being the first-ever probe to venture into interstellar space, where it's surrounded by untouched stardust and blankets of darkness? Yeah, it's extremely far away from us. And that means communicating with it takes a very (very) long time. Specifically, at the time of writing this article, Voyager 1 is more than 162 AUs away from Earth; one AU is equal to the distance between our planet and the sun. In total, it takes approximately 45 hours to complete one back-and-forth command with this spacecraft. Thus, "this process may take months," the team said.

To give you a silver lining, though, the scientists have confirmed that Voyager 1 is exhibiting what's known as a carrier tone, which runs along a wavelength that doesn't carry information but rather acts as a heartbeat. At the very least, we know it is alive.

"The spacecraft appears to be healthy other than the current issue. So if we can fix this, Voyager 1 should be able to continue its science mission," the team said. "But the Voyagers are already operating far, far beyond what anyone expected of them. We know the more time that goes by, the more issues are likely to arise. We’ll keep them going as long as we can, but we know they won't last forever."

"If V1 didn't make it? I'd be very proud; the mission has far exceeded the designers' expectations," Badaruddin said. "But really, that's hard to ponder because we still believe we can recover."

Alas, fingers crossed that Voyager 1 returns to its healthy self — but even if it doesn't, and is left alone to drift in space, we can be sure its legacy has already been firmly cemented in our books, in our hearts and in our history. 

Then, it'll be up to you, Voyager 2.

It has been out there for more than 45 years, having supplied us with a bounty of treasure like the discovery of two new moons of Jupiter, another incredible ring of Saturn and the warm feeling that comes from knowing pieces of our lives will drift across the cosmos even after we're gone. (See: The Golden Record.) But now, Voyager 1's fate seems to be uncertain.

As of Feb. 6, NASA said the team remains working on bringing the spacecraft back to proper health. "Engineers are still working to resolve a data issue on Voyager 1," NASA's Jet Propulsion Laboratory said in a post on X (formerly Twitter). "We can talk to the spacecraft, and it can hear us, but it's a slow process given the spacecraft's incredible distance from Earth."

Related: NASA's interstellar Voyager probes get software updates beamed from 12 billion miles away

So, on the bright side, even though Voyager 1 sits so utterly far away from us, ground control can actually communicate with it. In fact, last year, scientists beamed some software updates to the spacecraft as well as its counterpart, Voyager 2, from billions of miles away. Though on the dimmer side, due to that distance, a single back-and-forth communication between Voyager 1 and anyone on Earth takes a total of 45 hours. If NASA finds a solution, it won't be for some time.

The issue, engineers realized, has to do with one of Voyager 1's onboard computers known as the Flight Data System, or FDS. (The backup FDS stopped working in 1981.)

"The FDS is not communicating properly with one of the probe's subsystems, called the telemetry modulation unit (TMU)," NASA said in a blog post. "As a result, no science or engineering data is being sent back to Earth." This is of course despite the fact that ground control can indeed send information to Voyager 1, which, at the time of writing this article, sits about 162 AU's from our planet. One AU is equal to the distance between the Earth and the sun, or 149,597,870.7 kilometers (92,955,807.3 miles).

From the beginning 

Voyager 1's FDS dilemma was first noticed last year, after the probe's TMU stopped sending back clear data and started procuring a bunch of rubbish. 

As NASA explains in the blog post, one of the FDS' core jobs is to collect information about the spacecraft itself, in terms of its health and general status. "It then combines that information into a single data 'package' to be sent back to Earth by the TMU," the post says. "The data is in the form of ones and zeros, or binary code." 

However, the TMU seemed to be shuffling back a non-intelligible version of binary code recently. Or, as the team puts it, it seems like the system is "stuck." Yes, the engineers tried turning it off and on again. 

That didn't work. 

Then, in early February, Suzanne Dodd, Voyager project manager at NASA's Jet Propulsion Laboratory, told Ars Technica that the team might have pinpointed what's going on with the FDS at last. The theory is that the problem lies somewhere with the FDS' memory; there might be a computer bit that got corrupted. Unfortunately, though, because the FDS and TMU work together to relay information about the spacecraft's health, engineers are having a hard time figuring out where exactly the possible corruption may exist. The messenger is the one that needs a messenger.

They do know, however, that the spacecraft must be alive because they are receiving what's known as a "carrier tone." Carrier tone wavelengths don't carry information, but they are signals nonetheless, akin to a heartbeat. It's also worth considering that Voyager 1 has experienced problems before, such as in 2022 when the probe's "attitude articulation and control system" exhibited some blips that were ultimately patched up. Something similar happened to Voyager 2 during the summer of 2023, when Voyager 1's twin suffered some antenna complications before coming right back online again.

Still, Dodd says this situation has been the most serious since she began working on the historic Voyager mission.

Voyager 1's flight data system (FDS), which collects onboard engineering information and data from the spacecraft's scientific instruments, is no longer communicating as expected with the probe's telecommunications unit (TMU), according to a NASA blog post on Dec. 12. 

When functioning properly, the FDS compiles the spacecraft's info into a data package, which is then transmitted back to Earth using the TMU. Lately, that data package has been "stuck," the blog post said, "transmitting a repeating pattern of ones and zeros." Voyager's engineering team traced the problem back to the FDS, but it could be weeks before a solution is found. 

Related: NASA's interstellar Voyager probes get software updates beamed from 12 billion miles away

Voyager 1, and its twin spacecraft Voyager 2, launched in 1977 and have been operational longer than any other spacecraft in history. Both are in interstellar space, speeding into the cosmos more than 15 billion miles (24 billion kilometers) from Earth. 

They are so far away, in fact, that it takes nearly a day (22.5 hours) for a transmission to reach the spacecraft, and another day to receive any sort of response. A single back-and-forth communication with Voyager 1 takes 45 hours. So, whenever NASA engineers are able to send a fix for the probe's FDS, they will have to wait until the following day to find out if it works. 

And the solution won't be as simple as just turning the system on and off again (they tried that — it didn't work). The spacecraft's age and hardware present a unique set of challenges. NASA technicians must work within the framework and technology available to their predecessors in the 1970s, sometimes forcing some creative software work-arounds.

This isn't the first malfunction Voyager 1 has experienced in recent years. Issues with the probe's attitude articulation and control system (AACS) were noticed in May 2022, and persisted transmitting nonsense telemetry data for several months before a workaround was found.

Another update came in October 2023, with a software patch to help ultimately solve that issue, and also prevent residue build-up on the probes' thrusters. But these kinds of updates don't come quickly. NASA's blog clarifies, "finding solutions to challenges the probes encounter often entails consulting original, decades-old documents written by engineers who didn’t anticipate the issues that are arising today. As a result, it takes time for the team to understand how a new command will affect the spacecraft’s operations in order to avoid unintended consequences."

One update, a software fix, ought to tend to the corrupted data that Voyager 1 began transmitting last year, and another set aims to prevent gunk from building up in both spacecraft's thrusters. Together, these updates intend to keep the spacecraft in contact with Earth for as long as possible. 

"This far into the mission, the engineering team is being faced with a lot of challenges for which we just don’t have a playbook," Linda Spilker, project scientist for the mission at NASA's Jet Propulsion Laboratory, said in a statement. "But they continue to come up with creative solutions."

Related: Voyager: 15 incredible images of our solar system captured by the twin probes (gallery)

In May 2022, ground control began receiving gobbledygook from Voyager 1’s attitude articulation and control system (AACS), which keeps the probe’s antenna in line with Earth. As far as investigators can tell, the AACS’s hardware is in perfect working order; but, for some unknown reason, AACS had routed its telemetry data through a derelict onboard computer that garbled the data.

Engineers have now hammered together a software update, which they first delivered to Voyager 2 on Oct. 20. 

This bugfix won't answer why the AACS had diverted the telemetry data in the first place, however, a mystery that may hint at a larger problem with Voyager 1. Still, engineers are confident the patch should stem the issue — at least, after the update’s transmission completes its more-than-20-hour-long journey to Voyager 1.

Separately, the Voyager probes can adjust their antennas by firing thrusters. But each firing of a thruster leaves behind a layer of residue in the inlet tubes that let fuel into the thrusters themselves. Over decades of maneuvers, the residue has built up; engineers worry that the tubes might soon clog completely.

So, over September and October, engineers began allowing the spacecraft to rotate more— aiming to reduce how often the probes need to fire. If successful, the maneuvers should keep fuel flowing for another five years — at least.

Scientists taking a fresh look at 40-year-old data sent home by NASA's Voyager 2 spacecraft say that the satellites Titania and Oberon, which orbit the farthest from Uranus among the group, may have buried oceans 30 miles (50 kilometers) deep, while those of Ariel and Umbriel may be 19 miles (30 km) deep. The new research explains how the persistent internal heat of the Uranian moons and a few chemicals could make them watery worlds despite their location in the frigid outer reaches of the solar system.

"Finding oceans in the Uranian moons would increase the prospect that [...] ocean worlds are frequent in our solar system, and maybe — by extension — in other solar systems," Julie Castillo-Rogez, a planetary scientist at NASA's Jet Propulsion Laboratory in California and lead author of the new study, told Space.com in an email on Thursday (May 4).

Related: Uranus' moons: A guide to the ice giant's strange tilted moons

Early in their histories, Uranus' five largest moons — Titania, Oberon, Ariel, Umbriel and Miranda — likely hosted substantial oceans ranging from 62 miles to 90 miles (100 km to 150 km) deep, researchers said. 

"If the moons had benefited from long-term heating from their planet, then they could have maintained a thick ocean," Castillo-Rogez said.

For example, the Jupiter moon Europa and Saturn's Enceladus, both of which harbor big subsurface oceans, flex their innards and icy crusts in response to the strong gravitational pull from their host planets. Scientists think this tidal heat helps the moons maintain their subsurface water as a life-friendly liquid. But Uranus' tug is far weaker than that of Saturn or Jupiter, so oceans on even the planet's four largest moons are "mostly frozen by now," Castillo-Rogez said.

To understand more about how Uranus' largest moons may have evolved, her team built a model by gathering findings from NASA missions that studied other ocean worlds. These included Saturn's moon Enceladus, as observed by the Cassini mission; the dwarf planet Ceres, as revealed by Dawn; and Pluto's largest moon Charon, which New Horizons observed during its epic Pluto flyby in 2015.

The team's model revealed that the Uranian moons likely hold "thin oceans with high salt concentrations," according to the new study. This would be thanks to limited internal heat left over from their births, as well as considerable ammonia, whose antifreeze nature helps keep water in its liquid form even in very low temperatures.

The oceans on these Uranian moons have about 150 grams of salt for every liter of water, the researchers estimate. In comparison, Utah's Great Salt Lake in the United States is twice as salty, but life still manages to thrive in and around it.

The jury is still out on the ocean potential of Uranus' fifth-biggest moon, Miranda. Although previous research hinted at a hidden ocean to explain intriguing charged particles blasted into space, Miranda is so small that its internal ocean very likely froze just a few million years after it formed, researchers say in the latest study.

So far, Uranus has been briefly visited by only Voyager 2 — which spotted 10 new moons and a couple of new rings around the ice giant — during its January 1986 flyby. But Uranus may get more attention in the not-too-distant future, in part because exoplanet research has revealed that ice giants are among the most common, yet least understood, planets in the galaxy. 

NASA is developing a potential mission to the planet, currently given the placeholder name of Uranus Orbiter and Probe (UOP). As that moniker suggests, UOP would include an orbiter to gather data about the ice giant and its moons from afar and a probe that would drop into the planet's atmosphere for first-hand information, according to the mission concept.

The new study was published in December 2022 in the Journal of Geophysical Research.

Follow Sharmila Kuthunur on Twitter @skuthunur. Follow us on Twitter @Spacedotcom and on Facebook. 

NASA's long-running Voyager 2 mission will postpone an instrument shutdown three years to 2026 thanks to a technical feat by engineers. The change will allow the mission, which launched in 1977, to gather valuable science in deep space. 

"We are definitely interested in keeping as many science instruments operating as long as possible," Linda Spilker, Voyager's project scientist at NASA's Jet Propulsion Laboratory in southern California, said of the decision in a statement Wednesday (April 26.)

Voyager 2 and its twin, Voyager 1, will thus continue to gather valuable data deeper in space than any probes have before them. Ongoing investigations, NASA says, include examining the sun's magnetic field, the energy of the solar wind emanating from our sun and radio emissions in interstellar space.

Related: After 45 years, the 5-billion-year legacy of the Voyager 2 interstellar probe is just beginning

The Voyagers are both powered by nuclear energy, as the sun's rays are too weak for solar power so far out in deep space. The radioisotope thermoelectric generators (RTG) they use decay over time, meaning the plutonium produces a little less power every year.

Engineers have already shut down heaters, alongside other non-essential systems, to prioritize science for the robust spacecraft. But power is now so low that tough decisions had to come this year for Voyager 2's five science instruments. (Voyager 1 has only four running, due to a glitch with one instrument early in its lifespan, so it has enough power for all of them until 2024.)

Solving Voyager 2's power problems came down to removing a protection normally available to stop electricity surges from damaging the spacecraft's instruments. That protection is called a voltage regulator. This regulator triggers a backup circuit that takes an extra bit of power from the RTG as surge protection in case of problems.

"Instead of reserving that power, the mission will now be using it to keep the science instruments operating," NASA officials wrote in the statement. This decision will loosen voltage regulation on the spacecraft, but both the Voyagers have experienced "relatively stable" levels of power, "minimizing the need for a safety net."

Related: Voyager turns 45: What the iconic mission taught us and what's next

Engineers will monitor the success of this strategy on Voyager 2. If everything works, Voyager 1 will use the same technique as it begins to run short on power next year, NASA officials said. Everything has been working well on Voyager 2 for a few weeks with the new procedure, they noted.

"Variable voltages pose a risk to the instruments, but we've determined that it's a small risk, and the alternative offers a big reward of being able to keep the science instruments turned on longer," Suzanne Dodd, Voyager's project manager at JPL, said in the same statement. 

Both Voyagers were only expected to last four years in space and to collect solar system science at Jupiter and Saturn. A mission extension in 1981 allowed Voyager 2 to eventually fly past Uranus and Neptune, making it the only spacecraft yet to do so. Voyager 1 was high above the plane of the solar system after Saturn's flyby, but the spacecraft gathered valuable solar data from its trajectory because of the extension. 

Another mission extension in 1990 aimed to bring the Voyagers to interstellar space. Voyager 1 crossed into that region in 2012, while the slower-moving Voyager 2 achieved the milestone in 2018.

Elizabeth Howell is the co-author of "Why Am I Taller?" (ECW Press, 2022; with Canadian astronaut Dave Williams), a book about space medicine. Follow her on Twitter @howellspace. Follow us on Twitter @Spacedotcom or Facebook.

NASA's twin Voyager spacecraft launched back in the summer of 1977 on a "grand tour" of the solar system and are still exploring more than 45 years later.

Voyager 1 and Voyager 2 have both ventured into interstellar space and continue to beam data home to a small squad of remaining mission engineers and scientists.

This aged crew of engineers, operating out of unpretentious office space and foregoing promotions and planned retirement, have committed themselves to staying with the longest-running and farthest-reaching mission in NASA's history. Battling outdated technology and the march of time, Voyager's flight team sticks with humankind’s greatest exploration endeavor.  

Weigel Productions' "It's Quieter in the Twilight" is a new space documentary showcasing this dedicated team. Directed by Billy Miossi and produced by Matt Reynolds and Alissa Shapiro, the film arrives in theaters and on demand starting on May 19, 2023.  

Related: Voyager: 15 incredible images of our solar system captured by the twin probes (gallery)

Here’s the official synopsis:

They watch the bright lights from a distance today. The headlines now go to big names with bigger bank accounts. But, they are comfortable in the quiet; it suits them. Yet this quirky team of brilliant engineers — like the Voyager spacecraft they pilot — are pushing the notion of true discovery, traveling among stars propelled only by dwindling sunlight. While the world has moved on to fancier ships and splashier front men — the celestial journey of the aging spacecraft transcends earthly boundaries — from rural South Korea, the Jim Crow South and the U.S./Mexico border to cement a joint commitment to the mission which has traveled the furthest in human history as the clock winds down.

Featuring Voyager mission team members Sun Matsumoto, Enrique Medina, Fernando Peralta, Jefferson Hall, Todd Barber, Suzy Dodd and Chris Jones.

"There's a unique dichotomy that drew me into the story of the aging Voyager mission," Miossi said in a press statement. "The grandest feat of human exploration being steered by a humble few sitting in a drab office space. They seek no fame, no recognition. 

"Instead, they're content to quietly contribute a novel expertise for the sake of a deeper understanding of the vastness that exists beyond our world. Voyager is a once-in-a-lifetime, and perhaps many lifetimes, mission. And so much of what it has achieved over the past several decades is owed to a tiny team of engineers who have forgone promotions and, now, retirement. To understand them, their devotion, is what lies at the heart of 'It's Quieter in the Twilight.' I wanted the world to know these unsung explorers and to know the essential role they've played in humanity's most ambitious adventure."

Follow us on Twitter @Spacedotcom and on Facebook. 

Icy "rain" from Saturn's rings is heating the gas giant's atmosphere, a phenomenon never seen in the solar system before, a new study suggests. 

The unexpected discovery, which came as the result of examining data collected from various space missions including NASA's Hubble Space Telescope, the retired Cassini probe and the Voyager 1 and Voyager 2 spacecraft, could help researchers predict if exoplanets have ring systems.

The telltale evidence of the newfound phenomenon takes the form of a spectral line in light from Saturn, which represents hot hydrogen in the gas giant's atmosphere. This radiation "bump" indicates that something is contaminating the atmosphere and heating it from the outside. 

Related: Saturn's glorious rings up close (photos)

The most plausible explanation for this heating, study team members said, is icy particles raining down from the rings of Saturn, carrying with them energy that heats the planet's atmosphere through collisions with other particles. 

These raining particles may fall from the rings after being blasted by solar ultraviolet radiation, micrometeorites or particles from the solar wind. Alternatively, electromagnetic forces could be pulling charged dust particles out of the rings. When shaken loose, these particles are drawn by the tremendous gravity of Saturn down toward the planet. 

This particle rain was observed by the Cassini probe when it plunged into the gas giant's atmosphere at the end of its mission in September 2017. But the new study reveals fresh insights about this process.

"Though the slow disintegration of the rings is well known, its influence on the atomic hydrogen of the planet is a surprise," study lead author Lotfi Ben-Jaffel, of the Institute of Astrophysics in Paris and the Lunar and Planetary Laboratory at the University of Arizona, said in a statement. 

"Everything is driven by ring particles cascading into the atmosphere at specific latitudes," Ben-Jaffel added. "They modify the upper atmosphere, changing the composition, and then you also have collisional processes with atmospheric gases that are probably heating the atmosphere at a specific altitude."

The research team reached these conclusions by looking at ultraviolet-light (UV) observations from five space missions that have studied Saturn over the years. The two Voyager probes buzzed the gas giant in the 1980s, measuring UV radiation that researchers at the time dismissed as noise. Then, for years after it arrived at Saturn in 2004, Cassini measured UV data from the atmosphere of the gas giant. These observations were combined with additional data from Hubble and the multinational International Ultraviolet Explorer, which launched to Earth orbit in 1978. 

To then ensure that the UV data was accurate and represented an actual physical phenomenon at Saturn, the team turned to measurements made by the Space Telescope Imaging Spectrograph (STIS) instrument aboard Hubble. This data allowed the researchers to calibrate the archival UV observations.

"When everything was calibrated, we saw clearly that the spectra are consistent across all the missions. This was possible because we have the same reference point, from Hubble, on the rate of transfer of energy from the atmosphere as measured over decades," Ben-Jaffel said. "It was really a surprise for me. I just plotted the different light distribution data together, and then I realized, Wow  —  it's the same."

The team can use the data to follow UV levels at any location across Saturn, which points to the steady "ice rain" from Saturn's rings as the best explanation for the observations. 

"We are just at the beginning of this ring characterization effect on the upper atmosphere of a planet. We eventually want to have a global approach that would yield a real signature about the atmospheres on distant worlds," Ben-Jaffel said. "One of the goals of this study is to see how we can apply it to planets orbiting other stars. Call it the search for 'exo-rings.'"

The new study was published on Thursday (March 30) in the Planetary Science Journal.

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The general concept that the heliopause changes shape is not new; over the past decade, researchers have determined that it is not static. They made this discovery using data from Voyager 1 and Voyager 2, the only two spacecraft to exit the heliosphere thus far, as well as NASA's Interstellar Boundary Explorer (IBEX) satellite, which studies the emissions of energetic neutral atoms (ENAs) that are created when solar winds and the interstellar medium interact.

"The Voyager spacecraft provide the only direct, in situ measurement of the locations of these boundaries. But only at one point in space and time," Eric Zirnstein, a space physicist at Princeton University, wrote in an email to Vice. IBEX helps round out that data.

Related: There's a violent battle between solar wind and cosmic rays, and Voyager 2 just passed through it

Scientists have used the data to create models that predict how the heliopause changes. In a nutshell, solar winds and the interstellar medium push and pull on each other to create an ever-moving boundary. 

But recent research into the heliopause has surfaced data that contradict previous findings. Over a period of several months in 2014, IBEX captured the brightening of ENAs that indicated asymmetries in the heliopause, and the team later realized those asymmetries were incongruous with the models, Vice noted.

Furthermore, in reviewing data from the journeys of Voyager 1 and Voyager 2, the scientists discovered that the heliopause changed dramatically in a very short period of time. That helps to explain why there was such a large gap between the two probes' entrances into interstellar space, which happened in 2012 and 2018, respectively. But that kind of movement by the heliopause also clashes with the models.

In a paper published Oct. 10 in the journal Nature Astronomy, the researchers called these discrepancies "intriguing and potentially controversial." They plan to continue studying the heliopause, hoping to gain more insight from NASA's Interstellar Mapping and Acceleration Probe, a new-and-improved satellite that can detect ENAs and is scheduled to launch in 2025, Zirnstein told Vice.

Until then, we can only ponder this eerie phenomenon happening in the haunting depths of the solar system.

Follow Stefanie Waldek on Twitter @StefanieWaldek. Follow us on Twitter @Spacedotcom and on Facebook.

Stone has retired as the project scientist of Voyager, which sent twin probes on a historic "grand tour" of the solar system's giant planets and, much later, out to interstellar space. He had held the post since 1972 — five years before the launch of the twin spacecraft, which are still going strong.

"It has been an honor and a joy to serve as the Voyager project scientist for 50 years," Stone said in a NASA statement on Tuesday (Oct. 25). 

"The spacecraft have succeeded beyond expectation, and I have cherished the opportunity to work with so many talented and dedicated people on this mission," he added. "It has been a remarkable journey, and I’m thankful to everyone around the world who has followed Voyager and joined us on this adventure."

Related: Going interstellar: Q&A with Voyager project scientist Ed Stone

Voyager 1 and Voyager 2 launched a few weeks apart in 1977 and headed for the realm of the giant planets. Voyager 1 flew by Jupiter in March 1979 and then zoomed past both Saturn and its largest moon, Titan, in November 1980.

Voyager 2 performed flybys of Jupiter and Saturn as well, visiting the two planets in July 1979 and August 1981, respectively. The probe then got humanity's first-ever up-close looks at our solar system's "ice giants," flying past Uranus in January 1986 and Neptune in August 1989.

These close encounters taught scientists a great deal. Voyager 1's Jupiter flyby, for example, revealed extensive volcanism on Io, which we now know is the most volcanically active body in the solar system. Voyager 2 discovered 10 new moons of Uranus and found a nitrogen-ice volcano on Triton, Neptune's largest satellite.

But there was more history to be made. Both Voyagers kept on flying, all the way to the edge of the heliosphere, the huge bubble of charged particles and magnetic fields that the sun blows around itself. Voyager 1 crossed the heliopause, which marks the end of the heliosphere, in August 2012, becoming the first human-made object ever to enter interstellar space. Voyager 2 followed suit in November 2018.

Voyager 1 is now about 14.7 billion miles (23.7 billion kilometers) from our planet, or roughly 159 astronomical units (AU). (One AU is the Earth-sun distance — about 93 million miles, or 150 million km). Voyager 2 is about 12.3 billion miles (19.8 billion km) away, or nearly 132 AU from us.

Both spacecraft are still operational, gathering unprecedented data about this exotic, far-flung realm. And the information that continues to come in is, in part, a testament to Stone, team members said.

"Ed likes to say that Voyager is a mission of discovery, and it certainly is," Voyager project manager Suzanne Dodd said in the same statement. "From the flybys of the outer planets in the 1970s and '80s to the heliopause crossing and current travels through interstellar space, Voyager never ceases to surprise and amaze us. All those milestones and successes are due to Ed’s exceptional scientific leadership and his keen ability to share his excitement about these discoveries to the world."

Linda Spilker will succeed Stone, becoming the Voyager mission's second-ever project scientist. She was a member of the Voyager science team during the planet flyby era before leaving to do other things, including becoming project scientist for NASA's Cassini Saturn mission. Spilker rejoined Voyager as deputy project scientist last year.

It's unclear if the Voyagers will join Stone in hitting the half-century mark. Their nuclear power source is fading, and mission team members have had to turn off some instruments over the past few years to save juice. The probes have enough power and thruster fuel to keep operating in their current state until at least 2025, NASA officials have said, but the future beyond that is murky.

Even after death, the probes will continue to be emissaries for humanity, their existence proof of our own. With this in mind, both Voyagers carry "golden records" designed to teach aliens about us, should E.T. happen to stumble across either probe.

Mike Wall is the author of "Out There" (Grand Central Publishing, 2018; illustrated by Karl Tate), a book about the search for alien life. Follow him on Twitter @michaeldwall. Follow us on Twitter @Spacedotcom or on Facebook.  

Voyager 2 flew past Uranus in January 1986, discovering 10 moons and two rings while becoming the first and so far only spacecraft to visit the ice giant. One of those rings, which scientists call the zeta ring, has frustrated astronomers ever since — they weren't even able to spot it again for nearly two decades. But last year, researchers got an unexpected gift: a new image of the Uranus' ring system, including the elusive zeta ring, courtesy of amateur image processor Ian Regan.

"For a long time we thought we only had two images of this ring from Voyager 2," Matthew Hedman, a planetary scientist at the University of Idaho, said during a presentation at the annual meeting of the American Astronomical Society's Division of Planetary Sciences on Oct. 5. "This shows there's a lot of information still encoded in the Voyager data that deserves a second look."

Related: Uranus by 2049: Here's why scientists want NASA to send a flagship mission to the strange planet

Scientists originally missed the find because the reddish dusty ring closest to Uranus wasn't visible in any individual image — Regan had to combine a host of images together for the feature to appear. "He took hundreds of images, stacked them together, to produce this image of the Uranian system," Hedman said. "This is the most comprehensive view of the zeta ring that exists and we didn't know it was in the Voyager data for decades."

The new image combined with the previous two Voyager photographs offered Hedman and his colleagues enough information to calculate the ring's distance from Uranus, about 23,000 miles (37,000 kilometers) above the planet, and to estimate its brightness.

But both of those values are puzzling. The Keck Observatory in Hawai'i had gathered the first observations of the zeta ring since Voyager 2 in 2007. These observations showed the ring at 25,000 miles (40,000 km) above the planet — a bit farther from Uranus than the Voyager 2 observations showed.

"The trick is that the location of this ring didn't match the Voyager images," Hedman said of the Keck observations. "Something had changed about this ring over the course of 20 years. We're still not entirely sure what that was, though."

And the zeta ring didn't just inch away from the planet during those two decades it went unmonitored; it also registered a stronger signal in the Keck observations than it had in Voyager 2's view.

"It got significantly brighter, which means dust got introduced to the system sometime in those 20 years," Hedman said. "Now, what did that? We have no idea."

Hedman suggested that Uranus could have been hit by a space rock that fragmented into debris and settled in the zeta ring, or that perhaps the changing seasons could be responsible, but both are merely ideas. Whatever happened must have been dramatic enough to affect the rings, but also have slipped under scientists' radar.

NASA will begin planning a major mission to explore the Uranus system in the coming years, but scientists won't have data from that mission for a couple of decades. However, Hedman noted that the James Webb Space Telescope had captured a dazzling image of similar rings around Neptune, released in September.

"Fortunately, there is a telescope that seems to be very good at looking at dusty rings around planets," he said. "So that might be nice."

Email Meghan Bartels at mbartels@space.com or follow her on Twitter @meghanbartels. Follow us on Twitter @Spacedotcom and on Facebook.

Alice Gorman, Associate Professor in Archaeology and Space Studies, Flinders University

On Aug. 20, 1977, 45 years ago, an extraordinary spacecraft left this planet on a journey like no other. Voyager 2 was going to show us, for the first time, what the outer solar system planets looked like close-up. It was like sending a fly to New York City and asking it to report back.

Voyager 1 was launched after Voyager 2, on Sept.5. Attached to the flank of each Voyager was a Golden Record carrying greetings, sounds, images and music from Earth.

The spacecraft were more or less twins, but they had different trajectories and scientific instruments. While both flew by Jupiter and Saturn, Voyager 1 then sped onwards to interstellar space. Voyager 2 tarried to make the only visit ever to the ice giants, Uranus and Neptune.

Gallery: Celebrate 45 years of Voyager with these amazing images of our solar system

The many-colored worlds

Arriving at Uranus in 1986, Voyager 2 mapped pale blue-green clouds and a possible "dark spot," which was later confirmed by the Hubble Space Telescope. There was an unexpected magnetic field, which dragged a corkscrew trail of particles behind the planet as it rolled in its orbit. Ten new moons were discovered, including the grey, cratered Puck, and two new coal-black rings.

Three years later Voyager 2 reached Neptune and sent home images of teal and cobalt clouds swirled by winds up to 11,000 mph (18,000 kph). A slate-colored "great dark spot" indicated a storm the diameter of Earth. The largest moon, Triton, was blushed pink from methane ice and spouted geysers of frozen nitrogen.

No spacecraft has been back since.

Messages to the future

Even more than these glimpses of the far icy planets, what fascinates people about the Voyager mission is the famous Golden Records. A committee led by visionary astronomer Carl Sagan worked for over a year to assemble materials to represent planet Earth. The music garners the most attention as the "mix tape for the universe," but it's not the only highlight.

One of the sounds of Earth is the manufacture of stone tools, or "knapping." This is the most durable technology humans and their ancestors have devised, in use from around 3 million years ago to the present day. For most of human existence, the sound of stone striking stone to detach a sharp-edged cutting flake was heard daily in every community.

On the record, you can hear the thuds of stone against the sound of heartbeats.

In one of the 116 images, a Black scientist in a lab coat bends over a microscope, tiered earrings falling gracefully from her ears. The earrings were the subject of some debate: would a future alien viewer recognize the concept of "jewelry"? It was hoped this image, together with the photomicrograph of cells dividing in image 17, would help viewers figure out that the science of microscopy was known on our planet.

People recorded messages in 55 languages. Some are ancient languages, such as Akkadian and Hittite, not heard on Earth for thousands of years. The most common words used are "greetings," "peace" and "friend." The Portuguese greeting, spoken by Janet Sternberg, says simply "Peace and happiness to all."

The long farewell

Finally, in 2018, Voyager 2 joined Voyager 1 beyond the heliopause, where the solar wind is turned back by winds from interstellar space. Our galaxy is 100,000 light-years across, and Voyager 2 is now just under 18 light-hours away from Earth.

Both spacecraft send reedy signals that wend their way between the planets to the three antennas which are still listening: Tidbinbilla, Goldstone and Madrid.

Before they can truly leave, the Voyagers will have to travel through the Oort Cloud, a vast, dark sphere of icy objects surrounding the solar system, for another 20,000 years.

Slowly, Voyager 2's systems are being shut down to eke out the power as long as possible. But sometime in the 2030s there will be none left.

Even after Voyager 2 stops transmitting, it won't be completely dead. The half-life of the plutonium-238 in its nuclear power source is 87.7 years, while that of the the small patch of uranium-238 coating on the Golden Record is 4.5 billion years. Both elements are slowly turning into lead.

The radioactive transmutation of the elements is a kind of reverse alchemy at a cosmic time scale. This process of becoming will not end until there is nothing on Voyager 2 left to be transformed.

Cultural significance

Constant bombardment by dust particles will gradually erode the surfaces of Voyager 2, likely at a higher rate than Voyager 1 because it's traveling through different regions of interstellar space. However, its Golden Record should be at least partially legible after 5 billion years.

The Earth portrayed on the Golden Records will probably be unrecognizable even 100 years from now. The spacecraft and the records will remain as a fragmentary archaeological record for an unknowable future.

While the Golden Records are endlessly fascinating, the true cultural significance of the Voyagers lies in their location. The spacecraft are boundary markers showing the physical extent of human engagement with the universe.

When the Voyagers cease transmission, it will be like losing a sense. Telescopes can only show us so much: there is no substitute for being there.

Who will follow in their path?

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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The Voyager 1 probe launched 45 years ago, on Sept. 5, 1977, just weeks after its twin Voyager 2 but soon overtaking it. The two spacecraft were designed to fly past Jupiter and Saturn, taking advantage of a favorable solar system alignment. At the time, no one expected the spacecraft to still be working more than four decades later. But now, the Voyagers are stretching toward a round 50 years in space. Voyager 1 is currently more than 14.6 billion miles (23.5 billion kilometers) from Earth — that's more than 157 times the distance from our planet to the sun — and is traveling outward at a speed of 38,000 mph (60,000 kph).

"Today, as both Voyagers explore interstellar space, they are providing humanity with observations of uncharted territory," Linda Spilker, Voyager's deputy project scientist at NASA's Jet Propulsion Laboratory (JPL) in California, said in a statement. 

Gallery: Celebrate 45 years of Voyager with these amazing images of our solar system

Voyager 1 in particular has something to celebrate with this anniversary, since NASA recently managed to fix a glitch that had caused the spacecraft to rely on a defunct computer, which led to the probe sending gibberish data home to Earth.

Although mission personnel have gotten the spacecraft back on track, they're still looking into what triggered the switch, according to a NASA statement.

After the 1977 launch, the mission's milestones came fast. Voyager 1 got its first look at Jupiter in April 1978 and made its closest approach to the massive planet in March 1979. The spacecraft also caught glimpses of Jupiter's moons, including Io, the  strange volcanic surface of which Voyager 1 unveiled.

Then, the probe headed out to Saturn and its largest moon, Titan, making its flyby in November 1979, just over two years after launch. Voyager 1's detour to catch a closer look at Titan meant it didn't make any more flybys; its twin Voyager 2 instead continued sailing out to Uranus and Neptune.

Voyager 1 became the most distant human-made object in 1998, according to NASA, and marked 100 times the distance from Earth to the sun in 2006.

In 2012, Voyager 1 entered interstellar space, the region beyond the heliosphere, which is the bubble formed by charged particles constantly streaming off the sun and out into space. Beyond the heliosphere, the spacecraft registers far more cosmic rays — fragments of atoms that zip through space — than solar particles.

"This is the first time we've been able to directly study how a star, our sun, interacts with the particles and magnetic fields outside our heliosphere," Spilker added, "helping scientists understand the local neighborhood between the stars, upending some of the theories about this region and providing key information for future missions."

Although four instruments on the Voyager 1 probe are still gathering data to send to Earth, mission personnel expect they will need to turn off additional instruments as time passes and the probe's nuclear power source weakens.

Eventually, the twin probes will fall silent — although they will continue to zip through space for billions of years.

"The Voyagers have continued to make amazing discoveries, inspiring a new generation of scientists and engineers," Suzanne Dodd, project manager for Voyager at JPL, said in the same statement. "We don't know how long the mission will continue, but we can be sure that the spacecraft will provide even more scientific surprises as they travel farther away from the Earth."

Email Meghan Bartels at mbartels@space.com or follow her on Twitter @meghanbartels. Follow us on Twitter @Spacedotcom and on Facebook. 

After months of sending junk data about its health to flight controllers on Earth, the 45-year-old Voyager 1 is once again beaming back clear telemetry data on its status beyond our solar system. NASA knew the problem was somewhere in the spacecraft's attitude articulation and control system, or AACS, which keeps Voyager 1's antenna pointed at Earth. But the solution was surprising. 

"The AACS had started sending the telemetry data through an onboard computer known to have stopped working years ago, and the computer corrupted the information," NASA officials wrote in an update Tuesday (Aug. 30). The rest of the spacecraft was apparently fine, collecting data as it normal.

Related: Celebrate 45 years of Voyager with these amazing images (gallery)

Once engineers began to suspect Voyager 1 was using a dead computer, they simply sent a command to the probe so its AACS system would use the right computer to phone home. It was a low-risk fix, but time consuming. It takes a radio signal nearly 22 hours to reach Voyager 1, which was 14.6 billion miles (23.5 billion kilometers) from Earth and growing farther by the second as of Aug. 30.

With the Voyager 1 data glitch solved, NASA is now pondering a new mystery: what caused it in the first place. 

“We're happy to have the telemetry back," Voyager project manager Suzanne Dodd said in a statement. "We'll do a full memory readout of the AACS and look at everything it's been doing. That will help us try to diagnose the problem that caused the telemetry issue in the first place."

Related: Voyager 1 marks 10 years in interstellar space

Engineers suspect Voyager 1 began routing its health and status telemetry through the dead computer after receiving a bad command from yet another onboard computer. That would suggest some other problem lurking inside Voyager 1's computer brains, but mission managers don't think it's a threat to the iconic spacecraft's long-term health.

Still, they'd like to know exactly what's going inside Voyager 1. 

"So we're cautiously optimistic, but we still have more investigating to do," Dodd said in the statement. 

NASA launched the Voyager 1 spacecraft, and its twin Voyager 2, in 1977 on a mission to explore the outer planets of the solar system. Voyager 1 flew by Jupiter and Saturn during its primary mission and kept going, ultimately entering interstellar space in 2012, with Voyager 2 reaching that milestone in 2018. 

You can track the status of Voyager 1 and Voyager 2 on this NASA website.

Email Tariq Malik at tmalik@space.com or follow him @tariqjmalik. Follow us @Spacedotcom, Facebook and Instagram.

Allen Telescope Array (ATA), a recently refurbished radio observatory near San Francisco in California dedicated to the search for extraterrestrial life, made contact with the Voyager 1 probe on July 9, using 20 of its 42 dish antennas, which are each over 20 feet (6.1 meters) wide. The telescope recorded 15 minutes of data, according to a statement, which were stored on a disk. 

"The detection of Voyager 1, the farthest human-made object, with the refurbished Allen Telescope Array is an excellent display of the telescope's capabilities and strengths, and a representation of the outstanding hard work put by the ATA team since the start of the refurbishment program in 2019," the team said in the statement.

Related: Voyager 1 marks 10 years in interstellar space 

The statement didn't provide any additional information about the signal it caught. NASA has been investigating a strange glitch that has caused Voyager 1 to send back nonsense data about its location in space. NASA first reported the glitch in May, although it has not specified when the issue began. The agency is confident the spacecraft is safe because if the gibberish data were accurate, the signal from Voyager 1 wouldn't be properly pointed toward Earth.

Currently located about 14.5 billion miles (23.3 billion kilometers) away from Earth, 156 times the sun-Earth distance, Voyager 1 is still being tracked by NASA's Deep Space Network, sending a meager 160 bits per second of data back home. For comparison, a regular home broadband connection is measured in megabits per second, that is millions of bits per second.

The spacecraft, which entered what astronomers define as interstellar space 10 years ago, is measuring properties of the interstellar medium beyond the edge of the heliosphere, the bubble of plasma created by the sun that surrounds the planets.

Voyager 1 still has to fly through the Oort Cloud, a spherical disc of comets and asteroids at the farthest reaches of the solar system, more than 2,000 sun-Earth distances away from the sun. 

No spacecraft has ever visited the Oort Cloud and Voyager 1 will take about 300 years to get there. By then, however, the probe will long be dead as it's expected to run out of fuel to power its systems as early as 2025.

Follow Tereza Pultarova on Twitter @TerezaPultarova. Follow us on Twitter @Spacedotcom and on Facebook. 

On Aug. 25, 2012, NASA's Voyager 1 spacecraft was 11 billion miles (18 billion kilometers) from the sun and scientists determined that the venerable spacecraft had crossed the boundary between the sun's influence and the interstellar medium. Now, still going and still sending back data, Voyager 1 and its twin Voyager 2 — which joined it in interstellar space in 2018 — continue to conduct ground-breaking science. 

Launched in 1977, Voyager 1 and Voyager 2 were primarily designed to explore Jupiter and Saturn. Voyager 2 also visited Uranus and Neptune, while Voyager 1 instead prioritized Saturn's giant moon Titan, which sent it on a new trajectory to the edge of the solar system. It wasn't until after Voyager 2's flyby of Neptune in 1989 that Voyager's interstellar mission was created.

"Nobody ever expected the Voyagers to leave the interstellar medium," Merav Opher, an astronomer at Boston University who runs a center called SHIELD that's revisiting Voyager data in an effort to learn more about the heliosphere, told Space.com. "They had a five-year lifetime that was extended for another five years, then 10 years, but nobody really thought that they would be leaving the solar system."

What the twin spacecraft have discovered about the heliosphere — the magnetic bubble that surrounds us — could have consequences for our understanding of life on Earth. 

Related: Celebrate 45 years of Voyager with these amazing images of our solar system (gallery)

Voyager 1's interstellar moment 

Voyager 1 became the first human-made object to explore interstellar space — the space between the stars in a galaxy — when it was 122 astronomical units (AU) away from the sun. (One AU is the average distance between Earth and the sun and equals about 93 million miles or 150 million kilometers.)

Scientists know for sure that the Voyager probes have crossed from the heliosphere — where the solar wind, a stream of charged particles from the sun, dominates — into interstellar space because of particle density. 

"The density was 10 times larger than what we find in the solar wind at those distances," Opher said of readings from late 2018. Voyager 1 was out. 

Voyager 2's instruments detected the same jump in particle density when it entered interstellar space on Nov. 5, 2018. 

Revealing the heliopause 

The probes' crossing into interstellar space may have been clearcut, but the heliopause — a "twilight zone" between the bubble-like heliosphere and interstellar space — had unexpected properties. Each spacecraft took a couple of months to cross through, during which time they sent back data on peaks and troughs in plasma density. 

"We expected it to be a bleep, but the heliopause is not like a line or a door — it's much thicker and more complex than we thought," Opher said. "But it's also a boundary that allows communication." The amazing discovery that particles come in and out of the heliosphere was from magnetic field data first from Voyager 1 in 2012, then from Voyager 2 six years later. 

A magnetic mystery 

Voyager 1 and 2's data on magnetic fields in the heliopause confused scientists. There ought to have been a change where the magnetic field from the sun met that from space, with theorists expecting the magnetic field from the galaxy to be inclined to the solar magnetic field. But neither Voyager 1 nor Voyager 2 detected magnetic field direction changes. 

"When Voyager crossed there was no change in angle. The magnetic field stayed almost solar-like, with no rotation," Opher said. It's still a puzzle, but Opher and her collaborators have a theory about magnetic field flux tubes in the heliopause that connect the solar field with interstellar field. "It's almost like there are these highways for particles to go in and out of the heliosphere," she said, adding that it's probably a region where the magnetic field reconnects. 

The heliopause appears to be the warped surface of the heliosphere that responds to solar activity, but why remains an open question. 

Beyond the heliopause 

Voyager 1 is now 40 AU beyond the heliopause, enabling scientists to discover what the interstellar medium is really like. It turns out to be much more influenced by the heliosphere than previously thought. "The interstellar medium as measured by the Voyager probes is not quiet, it's agitated and influenced by the sun," Opher said. "It's so different than we expected and we still don't really understand what's going on." 

The data show that galactic cosmic rays behave differently depending on whether they're parallel or perpendicular to the sun's magnetic field. "We thought we'd see galactic cosmic rays coming from all directions, but they don't," Opher said. 

The data can be correlated to coronal mass ejections (CMEs) from the sun that cause disturbances in its magnetic field far out into the interstellar medium. It's forced scientists to rethink how cosmic rays can reach the Earth. 

What's next for the Voyagers 

The "silent ambassadors" will, eventually, go quiet as they enter what scientists call the pristine interstellar medium. As the sun's influence wanes and there's less turbulence, the probes will likely pick up a matter-mix from other stars. 

Detecting the influence of the next star along, however, is beyond the spacecraft. Voyager 1 will close in on a star in the Camelopardalis constellation called AC+79 3888 in 40,000 years while Voyager 2 is about the same flight-time from a star called Ross 248 in the constellation of Andromeda. 

With the two spacecraft now closing out their operational lifetimes as their power supplies run dry, the last time scientists hear from them will probably be in the 2030s at best, mission personnel have said. 

For scientists studying the heliosphere, the next spacecraft of interest will be New Horizons, the spacecraft that imaged Pluto in 2015. New Horizons will enter the heliopause around 2030, but its power supply won't last beyond the late 2030s. Meanwhile, scientists are considering Interstellar probe, a decades-long mission to study the heliosphere to build on the Voyagers' findings.  

Voyager and the search for life 

"There is nothing like in-situ data to reveal a new world and Voyager was instrumental in redefining what we understand about the heliosphere," said Opher, who thinks the heliosphere has shielded life on Earth from hazardous cosmic rays and dust. She also thinks that the solar system's position in the interstellar medium has been crucially important for fostering life. 

"If we are going to try to find life on other planets then the only habitable astrosphere we have a handle on is our own," Opher said. "It was Voyager that revealed its complexity." 

Follow us on Twitter @Spacedotcom and on Facebook. 

The probe launched on Sept. 5, 1977 — about two weeks after its twin Voyager 2 — and as of August 2022 is approximately 14.6 billion miles (23.5 billion kilometers) away from our planet, making it Earth's farthest spacecraft. Voyager 1 is currently zipping through space at around 38,000 mph (17 kilometers per second), according to NASA Jet Propulsion Laboratory.

When Voyager 1 launched a mission to explore the outer planets in our solar system nobody knew how important the probe would still be 45 years later The probe has remained operational long past expectations and continues to send information about its journeys back to Earth. 

Related: Celebrate 45 years of Voyager with these amazing images of our solar system (gallery)

The spacecraft entered interstellar space in August 2012, almost 35 years after its voyage began. The discovery wasn't made official until 2013, however, when scientists had time to review the data sent back from Voyager 1.

Voyager 1 was the second of the twin spacecraft to launch, but it was the first to race by Jupiter and Saturn. The images Voyager 1 sent back have been used in schoolbooks and by many media outlets for a generation. The spacecraft also carries a special record — The Golden Record — that's designed to carry voices and music from Earth out into the cosmos. 

According to NASA Jet Propulsion Laboratory (JPL), Voyager 1 has enough fuel to keep its instruments running until at least 2025. By then, the spacecraft will be approximately 13.8 billion miles (22.1 billion kilometers) away from the sun.  

The Grand Tour

The Voyager missions took advantage of a special alignment of the outer planets that happens just once every 176 years. This alignment allows spacecraft to gravitationally "slingshot" from one planet to the next, making the most efficient use of their limited fuel.

NASA originally planned to send two spacecraft past Jupiter, Saturn and Pluto and two other probes past Jupiter, Uranus and Neptune. Budgetary reasons forced the agency to scale back its plans, but NASA still got a lot out of the two Voyagers it launched.

Voyager 2 flew past Jupiter, Saturn, Uranus and Neptune, while Voyager 1 focused on Jupiter and Saturn.

Recognizing that the Voyagers would eventually fly to interstellar space, NASA authorized the production of two Golden Records to be placed on board the spacecraft. Sounds ranging from whale calls to the music of Chuck Berry were placed on board, as well as spoken greetings in 55 languages. 

The 12-inch-wide (30 centimeters), gold-plated copper disks also included pictorials showing how to operate them and the position of the sun among nearby pulsars (a type of fast-spinning stellar corpse known as a neutron star), in case extraterrestrials someday stumbled onto the spacecraft and wondered where they came from.

Both spacecraft are powered by three radioisotope thermoelectric generators, devices that convert the heat released by the radioactive decay of plutonium to electricity. Both probes were outfitted with 10 scientific instruments, including a two-camera imaging system, multiple spectrometers, a magnetometer and gear that detects low-energy charged particles and high-energy cosmic rays. Mission team members have also used the Voyagers' communications system to help them study planets and moons, bringing the total number of scientific investigations on each craft to 11.

Voyager 1 Jupiter flyby

Voyager 1 almost didn't get off the ground at its launch, as its rocket came within 3.5 seconds of running out of fuel on Sept. 5, 1977.

But the probe made it safely to space and raced past its twin after launch, getting beyond the main asteroid belt between Mars and Jupiter before Voyager 2 did. Voyager 1's first pictures of Jupiter beamed back to Earth in April 1978, when the probe was 165 million miles (266 million kilometers) from home.

To NASA's surprise, in March 1979 Voyager 1 spotted a thin ring circling the giant planet. It found two new moons as well — Thebe and Metis. Additionally, Voyager 1 sent back detailed pictures of Jupiter's big Galilean moons (Io, Europa, Ganymede and Callisto) as well as Amalthea.

Like the Pioneer spacecraft before it, Voyager's look at Jupiter's moons revealed them to be active worlds of their own. And Voyager 1 made some intriguing discoveries about these natural satellites. For example, Io's many volcanoes and mottled yellow-brown-orange surface showed that, like planets, moons can have active interiors.

Additionally, Voyager 1 sent back photos of Europa showing a relatively smooth surface broken up by lines, hinting at ice and maybe even an ocean underneath. (Subsequent observations and analyses have revealed that Europa likely harbors a huge subsurface ocean of liquid water, which may even be able to support Earth-like life.)

Voyager 1's closest approach to Jupiter was on March 5, 1979, when it came within 174,000 miles (280,000 km) of the turbulent cloud tops. Then it was time for the probe to aim for Saturn.

Voyager 1 visits Saturn and its moons

Scientists only had to wait about a year, until 1980, to get close-up pictures of Saturn. Like Jupiter, the ringed planet turned out to be full of surprises.

One of Voyager 1's targets was the F ring, a thin structure discovered only the year previously by NASA's Pioneer 11 probe. Voyager's higher-resolution camera spotted two new moons, Prometheus and Pandora, whose orbits keep the icy material in the F ring in a defined orbit. It also discovered Atlas and a new ring, the G ring, and took images of several other Saturn moons.

One puzzle for astronomers was Titan, the second-largest moon in the solar system (after Jupiter's Ganymede). Close-up pictures of Titan showed nothing but orange haze, leading to years of speculation about what it was like underneath. It wouldn't be until the mid-2000s that humanity would find out, thanks to photos snapped from beneath the haze by the European Space Agency's Huygens atmospheric probe.

The Saturn encounter marked the end of Voyager 1's primary mission. The focus then shifted to tracking the 1,590-pound (720 kg) craft as it sped toward interstellar space.

Two decades before it notched that milestone, however, Voyager 1 took one of the most iconic photos in spaceflight history. On Feb. 14, 1990, the probe turned back toward Earth and snapped an image of its home planet from 3.7 billion miles (6 billion km) away. The photo shows Earth as a tiny dot suspended in a ray of sunlight. 

Voyager 1 took dozens of other photos that day, capturing five other planets and the sun in a multi-image "solar system family portrait." But the Pale Blue Dot picture stands out, reminding us that Earth is a small outpost of life in an incomprehensibly vast universe.

Voyager 1 enters interstellar space

Voyager 1 left the heliosphere — the giant bubble of charged particles that the sun blows around itself — in August 2012, popping free into interstellar space. The discovery was made public in a study published in the journal Science the following year.

The results came to light after a powerful solar eruption was recorded by Voyager 1's plasma wave instrument between April 9 and May 22, 2013. The eruption caused electrons near Voyager 1 to vibrate. From the oscillations, researchers discovered that Voyager 1's surroundings had a higher density than what is found just inside the heliosphere.

It seems contradictory that electron density is higher in interstellar space than it is in the sun's neighborhood. But researchers explained that, at the edge of the heliosphere, the electron density is dramatically low compared with locations near Earth. 

Researchers then backtracked through Voyager 1's data and nailed down the official departure date to Aug. 25, 2012. The date was fixed not only by the electron oscillations but also by the spacecraft's measurements of charged solar particles. 

On that fateful day — which was the same day that Apollo 11 astronaut Neil Armstrong died — the probe saw a 1,000-fold drop in these particles and a 9% increase in galactic cosmic rays that come from outside the solar system. At that point, Voyager 1 was 11.25 billion miles (18.11 billion km) from the sun, or about 121 astronomical units (AU).

One AU is the average Earth-sun distance — about 93 million miles (150 million km).

Voyager 1's interstellar adventures

You can keep tabs on the Voyager 1's current distance and mission status on this NASA website.

Since flying into interstellar space, Voyager 1 has sent back a variety of valuable information about conditions in this zone of the universe. Its discoveries include showing that cosmic radiation out there is very intense, and demonstrating how charged particles from the sun interact with those emitted by other stars, mission project scientist Ed Stone, of the California Institute of Technology in Pasadena, told Space.com in September 2017.

The spacecraft's capabilities continue to astound engineers. In December 2017, for example, NASA announced that Voyager 1 successfully used its backup thrusters to orient itself to "talk" with Earth. The trajectory correction maneuver (TCM) thrusters hadn't been used since November 1980, during Voyager 1's flyby of Saturn. Since then, the spacecraft had primarily used its standard attitude-control thrusters to swing the spacecraft in the right orientation to communicate with Earth. 

As the performance of the attitude-control thrusters began to deteriorate, however, NASA decided to test the TCM thrusters — an idea that could extend Voyager 1's operational life. That test ultimately succeeded. 

"With these thrusters that are still functional after 37 years without use, we will be able to extend the life of the Voyager 1 spacecraft by two to three years," Voyager project manager Suzanne Dodd, of NASA's Jet Propulsion, Laboratory (JPL) in Southern California, said in a statement in December 2017.

Mission team members have taken other measures to extend Voyager 1's life as well. For example, they turned off the spacecraft's cameras shortly after the Pale Blue Dot photo was taken to help conserve Voyager 1's limited power supply. (The cameras wouldn't pick up much in the darkness of deep space anyway.) Over the years, the mission team has turned off five other scientific instruments as well, leaving Voyager 1 with four that are still functioning — the Cosmic Ray Subsystem, the Low-Energy Charged Particles instrument, the Magnetometer and the Plasma Wave Subsystem. (Similar measures have been taken with Voyager 2, which currently has five operational instruments.)

The Voyager spacecraft each celebrated 45 years in space in 2022, a monumental milestone for the twin probes.

"Over the last 45 years, the Voyager missions have been integral in providing this knowledge and have helped change our understanding of the sun and its influence in ways no other spacecraft can," says Nicola Fox, director of the Heliophysics Division at NASA Headquarters in Washington, in a NASA statement.

"Today, as both Voyagers explore interstellar space, they are providing humanity with observations of uncharted territory," said Linda Spilker, Voyager's deputy project scientist at JPL in the same NASA statement.

"This is the first time we've been able to directly study how a star, our Sun, interacts with the particles and magnetic fields outside our heliosphere, helping scientists understand the local neighborhood between the stars, upending some of the theories about this region, and providing key information for future missions." Spilker continues.

Voyager 1's next big encounter will take place in 40,000 years when the probe comes within 1.7 light-years of the star AC +79 3888. (The star is roughly 17.5 light-years from Earth.) However, Voyager 1's falling power supply means it will probably stop collecting scientific data around 2025.

Additional resources

You can learn much more about both Voyagers' design, scientific instruments and mission goals at JPL's Voyager site. NASA has lots of in-depth information about the Pale Blue Dot photo, including Carl Sagan's large role in making it happen, here. And if you're interested in the Golden Record, check out this detailed New Yorker piece by Timothy Ferris, who produced the historic artifact.  Explore the history of Voyager with this interactive timeline courtesy of NASA.  

Bibliography

• Bell, Jim. "The Interstellar Age: Inside the Forty-Year Voyager Mission," Dutton, 2015.
• Landau, Elizabeth. "The Voyagers in popular culture," Dec. 1, 2017. https://www.nasa.gov/feature/jpl/the-voyagers-in-popular-culture
• PBS, "Voyager: A history in photos." https://www.pbs.org/the-farthest/mission/voyager-history-photos/

Voyager 2 is now 12.1 billion miles (19.5 billion kilometers) away and still sending back data on the distant and unknown heliopause, and scientists are beginning to wonder how long the iconic space probe can keep going. 

Designed to take advantage of a once-every-176-years alignment in the 1970s that made it possible for spacecraft to take gravity-assist slingshots from planet to planet across the solar system, the Voyager mission consisted of two probes. Voyager 2 was the first to launch, with Voyager 1 following two weeks later. Both carried the famous "Golden Record," a 12-inch gold-plated copper disc containing sounds and images portraying the diversity of life and culture on Earth. 

Now over 14.5 billion miles (23.3 billion km) away, Voyager 1 is the farthest artificial object from Earth. But Voyager 2 is arguably more iconic because of its incredible multidecade tour of the giant planets. 

Related: Celebrate 45 years of Voyager with these amazing images of our solar system (gallery)

Voyager's "grand tour"

Though it launched second, Voyager 1 was so called because it was to reach Jupiter and Saturn first — in March 1979 and November 1980, respectively — before exiting the plane of the planets where it took the famous "Pale Blue Dot" photo. Voyager 2 visited four planets: Jupiter in July 1979, Saturn in August 1981, Uranus in January 1986 and Neptune in August 1989. 

"Both Voyager 1 and Voyager 2 provided tremendous legacies for planetary exploration," Jonathan Lunine, a planetary scientist and physicist at Cornell University who is working on the Juno, Europa Clipper and James Webb Space Telescope missions, told Space.com. "Not only in what they accomplished in terms of science, but also demonstrating that it was really possible to explore the outer solar system with a couple of spacecraft."

What did the Voyager probes reveal?

Voyager's discoveries are the stuff of legend among planetary scientists, many of whom still rely on the unique images from the spacecraft's wide-angle and narrow-angle cameras. The probes spotted volcanoes on Jupiter's moon Io, discovered that Jupiter's Great Red Spot is an Earth-size storm and found that the gas giant has faint rings. They studied Saturn's rings; saw the giant moon Titan's thick, Earth-like atmosphere; and revealed the tiny moon Enceladus to be geologically active. 

Voyager 2 alone then visited Uranus and Neptune. The spacecraft's first-ever images of Uranus revealed dark rings, the planet's tilted magnetic field and its geologically active moon Miranda. Neptune, meanwhile, was also discovered to have rings and many more moons than scientists initially thought. We also got to see Triton, a geologically active moon that is orbiting "backward" and, like Pluto, is now believed to be a captured dwarf planet from the Kuiper Belt.  

Voyager as a catalyst 

In addition to making groundbreaking discoveries, the Voyager mission helped scientists determine what merited deeper exploration. The mission revealed Jupiter to be an incredibly complex planet, thus spurring NASA to launch the Galileo mission in 1989 and the Juno mission in 2011. The Voyager probes' work also helped to inspire the iconic Cassini mission to Saturn.

"Voyager 1's close flyby of Titan was the catalyst for the wonderful Cassini mission to Saturn and its Huygens probe," Lunine said. The Huygens probe landed on the surface of Titan in 2005 and sent back an incredible video. 

Voyager 2 has also been a catalyst for investigations into the role of the ice giant planets — not only in the solar system but also in distant star systems, since most of the exoplanets found so far are roughly the size of Neptune and Uranus. 

Voyager and NASA today 

NASA has spent decades following up on the Voyager missions, and those efforts continue today. The space agency's Dragonfly mission will reach Titan, Saturn's largest moon, in 2034, while Europa Clipper will study Jupiter's ocean moon, first imaged by Voyager, starting in 2030. In April, the National Academies Planetary Science Decadal Survey recommended that NASA send a $4.2 billion Uranus Orbiter and Probe mission to unveil the mysterious ice giant planet and its moons in the 2040s. 

It's the latest mission that's a direct consequence of Voyager 2's brief visit to the Uranus system in January 1986. "Voyager 2's flyby of Uranus was a bull's-eye — it went directly through the plane of the moons' orbits because of the orientation of Uranus' axis to the sun," Lunine said. That made it unlike flybys at other planets, where the probes were able to visit one moon after another. "Voyager 2 got very brief images from these moons, so they're largely unexplored," Lunine said. 

Ariel and Miranda, in particular, are thought to be ocean worlds and so would be specifically targeted by the Uranus Orbiter and Probe. "It's been 45 years since the launch of Voyager 1 and Voyager 2, and here we are now finally talking about a Uranus Orbiter and Probe mission," Lunine said. "It seems like a long time because these missions take so long to conceive of, fund, build, launch and execute, but it all comes from the intriguing peeks that we got from Voyager 2." 

How long will Voyager last?

Both Voyager 1 and Voyager 2 still communicate with NASA's Deep Space Network (which itself was created to communicate with Voyager 2 at Uranus and Neptune), receiving routine commands and occasionally transmitting data to Earth. "We are still getting data from Voyager," Stamatios Krimigis, principal investigator for the Voyager 1 and 2 probes and the Voyager Interstellar Mission, said during a news conference held at COSPAR 22 in July. "We're looking forward to getting data for probably another five or six years."  

Around the mid- to late 2020s, the probes' scientific instruments will be entirely switched off, and eventually, the spacecraft will go cold and silent — but their journeys into interstellar space will continue indefinitely. "My motto is, I want to be here after Voyager passes on," said Krimigis, who is in his 80s. "But I'm not sure that's going to happen."  

In around 300 years, Voyager 1 and 2 will enter the Oort cloud, the sphere of comets surrounding the solar system. About 30,000 years later, they'll exit the neighborhood and silently orbit the center of the Milky Way for millions of years. 

Their scientific work may be almost over, but the Voyager spacecraft have only just begun their journeys into the cosmos.

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NASA's Voyager probes to interstellar space are icons of cosmic exploration, and you can celebrate their 45th anniversary with a free science webcast tonight (Aug. 18). 

The space agency's Jet Propulsion Laboratory (JPL) in Pasadena, California will host a live lecture tonight at 7 p.m. PDT (10 p.m. EDT, 0200 GMT) to showcase the Voyager mission, which launched two spacecraft toward the outer solar system in 1977. The first of those to launch, Voyager 2, lifted off 45 years ago this weekend. 

Related: Celebrate 45 years of Voyager with amazing solar system images (gallery)

Brian White of JPL's Public Services Office will host the webcast, which will feature Voyager project manager Suzanne Dodd and be co-hosted by JPL spokesperson Calla Cofield. You can watch it in the live feed above or directly from JPL's YouTube channel.

"As the twin Voyager spacecraft approach their 45th anniversary, we take a look at where the mission has been, what they've taught us and where they go from here," JPL officials said in an announcement. "In this conversation with Suzanne Dodd, Voyager Project Manager, we’ll discuss how Voyager came to be, highlight some of the major discoveries, and hear stories about this mission that has captured the public’s attention for years."

NASA launched Voyager 2 on Aug. 20, 1977, with the Voyager 1 mission following a few weeks later on Sept. 5. The twin spacecraft sailed on a tour of the outer planets, with Voyager 2 visiting Jupiter, Saturn, Uranus and Neptune. Voyager 1, meanwhile, flew by Jupiter and Saturn. 

The two spacecraft captured stunning close-up images of the outer planets, with Voyager 1 snapping the famed "Pale Blue Dot" image of Earth as seen from a distance of 3.7 billion miles (6 billion kilometers) from the sun. The image, which shows all of humanity as a faint blue speck in the dark void of space, became an icon of exploration and the vastness of the cosmos. 

In 2012, Voyager 1 made history when it became the first spacecraft to enter interstellar space. Voyager 2 followed suit in December 2018. The two spacecraft are the farthest human-built objects in space and NASA's longest-running space missions in history.

Email Tariq Malik at tmalik@space.com or follow him @tariqjmalik. Follow us @Spacedotcom, Facebook and Instagram.

NASA's twin probes Voyager 1 and Voyager 2 have captured some truly remarkable images of our solar system and are currently roaming through interstellar space. 

Despite its name Voyager 2 launched before Voyager 1, when it lifted off from Cape Canaveral Space Launch Complex 41 aboard a Titan IIIE-Centaur on Aug. 20, 1977. Voyager 1 followed suit about two weeks later on Sept. 5. 

While Voyager 1 primarily focused on Jupiter and Saturn, Voyager 2 visited both gas giants and then ventured on to Uranus and Neptune. But the duo didn't stop there. Voyager 1 officially entered interstellar space on Aug. 25, 2012, while Voyager 2 entered on Nov. 5, 2018. The pair continue to journey through the cosmos and have enough power and fuel to keep scientific instruments running until at least 2025, according to NASA. 

Here we celebrate the achievements of both Voyager 1 and Voyager 2 with some incredible images captured by the pair. 

This image was taken when NASA's Voyager 1 spacecraft zoomed toward Jupiter in January and February 1979, capturing hundreds of images during its approach, including this close-up of swirling clouds around Jupiter's Great Red Spot. 

This image of the Earth and moon are in a single frame. Voyager was the first spacecraft to achieve this and captured the iconic image on Sept. 18, 1977, by Voyager 1 when it was 7.25 million miles from Earth. The moon is at the top of the picture and beyond the Earth as viewed by Voyager. 

Color composite by Voyager 2 showing Jupiter's faint ring system. Images captured in July 1979. 

A Voyager 1 image of Jupiter's moon Io showing the active plume of the volcano Loki. The heart-shaped feature southeast of Loki consists of fallout deposits from the active plume Pele. The images that make up this mosaic were taken from an average distance of approximately 340,000 miles (490,000 kilometers) from the moon. 

Layers of haze covering Saturn's moon Titan are seen in this image taken by Voyager 1 on Nov. 12, 1980, at a range of 13,700 miles (22,000 km). This false-color image shows the details of the haze that covers Titan. The upper level of the thick aerosol above the moon's limb appears orange. 

This view of Uranus was recorded by Voyager 2 on Jan. 25, 1986, as the spacecraft left the planet behind and set forth on the cruise to Neptune. Even at this extreme angle, Uranus retains the pale blue-green color seen by ground-based astronomers and recorded by Voyager during the historic encounter. 

This Voyager 2 high-resolution color image provides obvious evidence of vertical relief in Neptune's bright cloud streaks. These clouds were observed at a latitude of 29 degrees north near Neptune's east terminator, the "line" on a planet where daylight meets darkness. 

Global color mosaic of Triton, taken in 1989 by Voyager 2 during its flyby of the Neptune system. The color was synthesized by combining high-resolution images taken through orange, violet and ultraviolet filters; these images were displayed as red, green and blue images and combined to create this color version. 

Saturn and three of its moons, Tethys, Dione and Rhea, seen by a Voyager spacecraft on Aug. 4, 1982, from a distance of 13 million miles (21 million km). 

This narrow-angle color image of the Earth, dubbed the "Pale Blue Dot," is a part of the first ever 'portrait' of the solar system taken by Voyager 1. The spacecraft acquired a total of 60 frames for a mosaic of the solar system from a distance of more than 4 billion miles (6 billion km) from Earth and about 32 degrees above the ecliptic, which is the plane that contains most of the planets of the solar system. 

Voyager 1 took photos of Jupiter and two of its satellites (Io, left, and Europa).

Enhanced color view of Saturn's ring system captured by Voyager 2 on Aug. 17, 1981, at a distance of 5.5 million miles (8.9 million km). The color variations between the rings possibly indicate variations in chemical composition from one part of Saturn's ring system to another.  

Close-up of the surface of Jupiter's moon Europa captured by Voyager 2 at a distance of 152,000 miles (246,000 km). 

Voyager 2 captured this image of Neptune's rings on Aug. 26, 1989, from a distance of 175,000 miles (280,000 km).  

A false-color image of Callisto captured on July 7, 1979, by Voyager 2 at a distance of about 677,000 miles (1.09 million km). Callisto is the second largest moon of Jupiter and is the most heavily cratered of the Galilean satellites. 

The probe was launched aboard a Titan IIIE-Centaur from Cape Canaveral Space Launch Complex 41 (previously Launch Complex 41) on Aug. 20, 1977, its twin spacecraft Voyager 1 was launched about two weeks later on Sept. 5. NASA planned for the Voyager spacecraft to take advantage of an alignment of the outer planets that takes place only every 176 years. The alignment would allow both probes to swing from one planet to the next, with a gravity boost to help them along the way.

While Voyager 1 focused on Jupiter and Saturn, Voyager 2 visited both those planets and also ventured to Uranus and Neptune. Voyager 2's mission to those last two planets would be humanity's only visit in the 20th century.

Related: Celebrate 45 years of Voyager with these amazing images of our solar system (gallery)

Voyager 2 is now traveling through interstellar space. As of early November 2018, NASA announced that Voyager 2 had crossed the outer edge of our solar system (Voyager 1 crossed the boundary into interstellar space in 2012.) Voyager 2 is now approximately 12 billion miles (19 billion kilometers) away from Earth and counting!  

Voyager 2 as the backup

Although there was not enough money in Voyager 2's budget to guarantee it would still work when flying past Uranus and Neptune, its trajectory was designed to go past those planets anyway. If the spacecraft were still working after Saturn, NASA could try to take pictures of the other planets.

Voyager 2 was ready as a backup for Voyager 1. If Voyager 1 failed when taking pictures of Jupiter and Saturn, NASA was prepared to alter Voyager 2's path to follow Voyager 1's trajectory. It would cut off the Uranus and Neptune option, but still, preserve the possibility of capturing images.

The backup plan was never executed, though, because Voyager 1 went on to make many discoveries at Jupiter and Saturn, working well enough for NASA to carry out its original plans for Voyager 2.

Jupiter and Saturn flyby

Voyager 2 reached Jupiter in 1979, two years after launching from Cape Canaveral. Since Voyager 1 had just gone through the system four months earlier, Voyager 2's arrival allowed NASA to take valuable comparison shots of Jupiter and its moons. It captured changes in the Great Red Spot and also resolved some of the moon's surfaces in greater detail.

Voyager 2 took pictures of many of Jupiter's satellites. Among its most spectacular findings were pictures from the icy moon Europa. Voyager 2 snapped detailed photos of the icy moon's cracks from 128,000 miles (205,996 km) away and revealed no change in elevation anywhere on the moon's surface.

Proving that moons are abundant around the outer planets, Voyager 2 happened to image Adrastea, a small moon of Jupiter, only months after Voyager 1 found two other Jupiter moons, Thebe and Metis. Adrastea is exceptionally small, only about 19 miles (30.5 kilometers) in diameter at the smallest estimate.

Next in line was Saturn. Voyager 2  became the third spacecraft to visit Saturn when it arrived at its closest point to the ringed planet on Aug. 26, 1981, and took hundreds of pictures of the planet, its moons and its rings. Suspecting that Saturn might be circled by many ringlets, scientists conducted an experiment. They watched the star Delta Scorpii for nearly two and a half hours as it passed through the plane of the rings. As expected, the star's flickering light revealed ringlets as small as 330 feet (100 meters) in diameter. 

Uranus and Neptune flyby

Voyager 2's made its closest approach to Uranus on Jan. 24, 1986, becoming the first spacecraft to visit the ice giant. The probe made several observations of the planet, noting that the south pole was facing the sun and that its atmosphere is about 85% hydrogen and 15% helium. 

Additionally, Voyager 2 discovered rings around Uranus, 10 new moons and a magnetic field that, oddly, was 55 degrees off the planet's axis. Astronomers are still puzzling over Uranus' orientation today.

Voyager 2's pictures of the moon Miranda revealed it to be perhaps the strangest moon in the solar system. Its jumbled-up surface appears as though it was pushed together and broken apart several times.

The spacecraft then made it to Neptune, reaching the closest point on Aug. 25, 1989. It skimmed about 3,000 miles from the top of the planet's atmosphere and spotted five new moons as well as four rings around the planet. Remarkably, Voyager 2 is currently the only human-made object to have flown by the intriguing ice giant, according to NASA.

Voyager 2's interstellar adventure

On November 5, 2018, Voyager 2 crossed the heliopause — the boundary between the heliosphere and interstellar space. At this stage, the probe was 119 astronomical units from the sun. (One AU is the average Earth-sun distance, which is about 93 million miles, or 150 million kilometers.) Voyager 1 made the crossing at nearly the same distance, 121.6 AU.

According to NASA Jet Propulsion Laboratory (JPL), Voyager 2 has enough fuel to keep its instruments running until at least 2025. By then, the spacecraft will be approximately 11.4 billion miles (18.4 billion kilometers) away from the sun. 

But Voyager 2 is destined to roam the Milky Way long after its instruments have stopped working.

In about 40,000 years Voyager 2 will pass 1.7 light-years (9.7 trillion miles) from the star Ross 248, according to NASA JPL. The cosmic vagabond will continue its journey through interstellar space and pass 4.3 light-years, (25 trillion miles) from Sirius in about 296,000 years. 

Voyager 2's legacy

Voyager 2's observations paved the way for later missions. The Cassini spacecraft, which was at Saturn between 2004 and 2017, tracked down evidence of liquid water at the planet's icy moons several decades after the Voyagers initially revealed the possible presence of water. Cassini also mapped the moon, Titan, after the Voyagers took pictures of its thick atmosphere.

Voyager 2's images of Uranus and Neptune also serve as a baseline for current observations of those giant planets. In 2014, astronomers were surprised to see giant storms on Uranus — a big change from when Voyager 2 flew by the planet in 1986. 

Additional information

To see where Voyager 2 is now you can check out the mission status with resources from NASA. Learn more about the iconic spacecraft with the National Air and Space Museum.  

Bibliography

NASA. In depth: Voyager 2. NASA. Retrieved August 17, 2022, from www.solarsystem.nasa.gov/missions/voyager-2/in-depth/

NASA. Voyager - mission status. NASA. Retrieved August 17, 2022, from www.voyager.jpl.nasa.gov/mission/status/

NASA. Voyager - the interstellar mission. NASA. Retrieved August 17, 2022, from www. voyager.jpl.nasa.gov/mission/interstellar-mission

But each Voyager spacecraft is powered by a finite nuclear energy source, and both sources are dwindling to dangerously low levels. Each spacecraft carries a store of the radioactive isotope plutonium-238; as the isotope decays, it releases energy that is converted into electricity by three radioisotope thermoelectric generators (RTGs). At launch, the RTGs provided each spacecraft with 450 watts of power. Now, they're producing less than half that amount and their electrical output is decaying by four watts each year.

"It takes about 200 watts, approximately, to run the transmitter on the spacecraft, to be able to send signals back to Earth, and we're at a power level currently where we only have about five to six watts of power margin on each spacecraft," Voyager Interstellar Mission project manager Suzanne Dodd, who also serves as the director for the Interplanetary Network Directorate at NASA's Jet Propulsion Laboratory (JPL) in California, told Space.com.

Related: 40 photos from NASA's epic 'grand tour' mission

The show isn't over yet, though. The Voyager teams have been strategically conserving power by turning off certain subsystems on both spacecraft, such as certain heaters, allowing others to function longer. 

Miraculously, the remaining science instruments are so far performing well even in the cold temperatures. "It's great that we get data far beyond what we thought we could as far as operating the instruments cold," Dodd said.

Between the anniversaries of each spacecraft's launch this summer, the Voyager instrument teams will hold a meeting to discuss their recent results. The pooled data becomes the foundation for a new model that will guide future plans for both spacecraft, including any instrument shut-downs. With conservation methods, Dodd estimates that the spacecraft could operate for another five years, if their operation depended solely on power. "And if we got really lucky, maybe doing some operating below some thresholds, we might be able to go out to the 2030s," she said.

But the advanced age of the spacecraft poses another problem: general failure of hardware and software. For instance, just a few months ago, Voyager 1's attitude articulation and control system (AACS), which orients the spacecraft and its communications antenna, began sending bad telemetry data back to Earth. That said, mission personnel know that the AACS is actually operating just fine because the signal from its antenna has remained stable — it just seems to be confused about its positioning. 

"We can command the spacecraft and the spacecraft can send back the science data to us, so it's really operating as normal," Dodd said. "It's just this one computer system can't tell us that it's operating as normal."

Such anomalies are expected to pop up as both Voyagers age, and a glitch could ultimately lead to losing a spacecraft, even if it still has power. But however long Voyager 1 and 2 continue to operate, the Voyager mission is already a massive success. The original mission was to perform flybys of the solar system's gas planets and their moons and beam back data to Earth — tasks that both spacecraft had completed by 1989. 

Then the secondary Voyager Interstellar Mission was initiated, tasking the Voyager spacecraft with obtaining information about the mysteries of space beyond the sun's influence. "How do things change as you go further and further away from the sun?" Dodd said. "And how does the magnetic field interaction with interstellar space change as you go further and further out? How does plasma density change as we go further and further out?"

There's only one way to answer those questions, she noted. "The key here is to keep the spacecraft operating and returning data as long as possible."

Follow Stefanie Waldek on Twitter @StefanieWaldek. Follow us on Twitter @Spacedotcom and on Facebook.

The Voyager 1 mission launched in 1977 with a design lifetime of five years. Nearly 45 years and a series of planetary flybys later, the spacecraft is now around 14.5 billion miles (23.3 billion kilometers) from Earth, exploring interstellar space. The spacecraft has made countless discoveries, but has also suffered a number of anomalies and mysteries. The latest of these is junk telemetry data being sent back to Earth.

"We have a problem with the Voyager 1 spacecraft," Thomas Zurbuchen, NASA's associate administrator for the Science Mission Directorate, said at a meeting of the National Academies of Sciences, Engineering and Medicine's Space Studies Board on Thursday (June 9), where he offered more details about the situation and what it might mean for the mission.

Voyager at 40: 40 photos from NASA's epic 'grand tour' mission

While the spacecraft is operating well, messages from the Voyager's Attitude Articulation and Control System, which keeps the spacecraft and its antenna in the proper orientation, are "not reflecting what's actually happening on board," Zurbuchen said.

Getting to the bottom of this confusion is no easy matter, however, due to the vast distance between Earth and Voyager 1, meaning long delays in the time it takes to communicate with Voyager 1, almost making the spacecraft a victim of its longevity. "Imagine you have a conversation with somebody in which you can only say a word every day," Zurbuchen said. "And you only hear back every other day. That's the kind of discussion that we have."

Zurbuchen is confident that the Voyager team will solve the mystery, but noted that the spacecraft cannot continue forever. In addition to the current communications issue, Voyager 1 is also running at much colder temperatures than it was designed to because of the decay of the spacecraft's nuclear power source.

"I'm not telling you that it's the end of that mission," he emphasized, noting that the team behind the mission has addressed many glitches over Voyager's long life.

"Make no mistake, there were issues, even since I'm at NASA, that really were concerning about Voyager; the team has solved it," he said. "But also, if one day, it's no longer solved, it is an immediate success and we should take out the champagne."

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This article was originally published at The Conversation. The publication contributed the article to Space.com's Expert Voices: Op-Ed & Insights.

James Edward Huchingson, Professor Emeritus and Lecturer in Religion and Science, Florida International University

Voyager 1 is the farthest human-made object from Earth. After sweeping by Jupiter, Saturn, Uranus and Neptune, it is now almost 15 billion miles (24 billion kilometers) from Earth in interstellar space. Both Voyager 1 and its twin, Voyager 2, carry little pieces of humanity in the form of their Golden Records. These messages in a bottle include spoken greetings in 55 languages, sounds and images from nature, an album of recordings and images from numerous cultures, and a written message of welcome from Jimmy Carter, who was U.S. president when the spacecraft left Earth in 1977.

The Golden Records were built to last a billion years in the environment of space, but in a recent analysis of the paths and perils these explorers may face, astronomers calculated that they could exist for trillions of years without coming remotely close to any stars.

Having spent my career in the field of religion and science, I've thought a lot about how spiritual ideas intersect with technological achievements. The incredible longevity of the Voyager spacecraft presents a uniquely tangible entry point into exploring ideas of immortality.

For many people, immortality is the everlasting existence of a soul or spirit that follows death. It can also mean the continuation of one's legacy in memory and records. With its Golden Record, each Voyager provides such a legacy, but only if it is discovered and appreciated by an alien civilization in the distant future.

Life after death

Religious beliefs about immortality are numerous and diverse. Most religions foresee a postmortem career for a personal soul or spirit, and these range from everlasting residence among the stars to reincarnation.

The ideal eternal life for many Christians and Muslims is to abide forever in God’s presence in heaven or paradise. Judaism’s teachings about what happens after death are less clear. In the Hebrew Bible, the dead are mere "shades" in a darkened place called Sheol. Some rabbinical authorities give credence to the resurrection of the righteous and even to the eternal status of souls.

Immortality is not limited to the individual. It can be collective as well. For many Jews, the final destiny of the nation of Israel or its people is of paramount importance. Many Christians anticipate a future general resurrection of all who have died and the coming of the kingdom of God for the faithful.

Jimmy Carter, whose message and autograph are immortalized in the Golden Records, is a progressive Southern Baptist and a living example of religious hope for immortality. Now battling brain cancer and approaching centenarian status, he has thought about dying. Following his diagnosis, Carter concluded in a sermon: "It didn't matter to me whether I died or lived. … My Christian faith includes complete confidence in life after death. So I'm going to live again after I die."

It is plausible to conclude that the potential of an alien witnessing the Golden Record and becoming aware of Carter's identity billions of years in the future would offer only marginal additional consolation for him. Carter's knowledge in his ultimate destiny is a measure of his deep faith in the immortality of his soul. In this sense, he likely represents people of numerous faiths.

Secular immortality

For people who are secular or nonreligious there is little solace to be found in an appeal to the continuing existence of a soul or spirit following one's death. Carl Sagan, who came up with the idea for the Golden Records and led their development, wrote of the afterlife: "I know of nothing to suggest that it is more than just wishful thinking." He was more saddened by thoughts of missing important life experiences — like seeing his children grow up — than fearful about the expected annihilation of his conscious self with the death of his brain.

For those like Sagan there are other possible options for immortality. They include freezing and preserving the body for future physical resurrection or uploading one's consciousness and turning it into a digital form that would long outlast the brain. Neither of these potential paths to physical immortality has proved to be feasible yet.

The Voyagers and legacy

Most people, whether secular or religious, want the actions they do while alive to bear continuing meaning into the future as their fruitful legacy. People want to be remembered and appreciated, even cherished. Sagan summed it up nicely: "To live in the hearts we leave behind is to live forever."

With Voyagers 1 and 2 estimated to exist for more than a trillion years, they are about as immortal as it gets for human artifacts. Even before the sun's expected demise when it runs out of fuel in about 5 billion years, all living species, mountains, seas and forests will have long been obliterated. It will be as if we and all the marvelous and extravagant beauty of planet Earth never existed — a devastating thought to me.

But in the distant future, the two Voyager spacecraft will still be floating in space, awaiting discovery by an advanced alien civilization for whom the messages on the Golden Records were intended. Only those records will likely remain as testimony and legacy of Earth, a kind of objective immortality.

Religious and spiritual people can find solace in the belief that God or an afterlife waits for them after death. For the secular, hoping that someone or something will remember humanity, any wakeful and appreciative aliens will have to do.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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NASA's Voyager 1 mission launched in 1977, passed into what scientists call interstellar space in 2012 and just kept going — the spacecraft is now 14.5 billion miles (23.3 billion kilometers) away from Earth. And while Voyager 1 is still operating properly, scientists on the mission recently noticed that it appeared confused about its location in space without going into safe mode or otherwise sounding an alarm.

"A mystery like this is sort of par for the course at this stage of the Voyager mission," Suzanne Dodd, project manager for Voyager 1 and its twin, Voyager 2, at NASA's Jet Propulsion Laboratory in California, said in a statement.

Related: Pale Blue Dot at 30: Voyager 1's iconic photo of Earth from space reveals our place in the universe

"The spacecraft are both almost 45 years old, which is far beyond what the mission planners anticipated," Dodd added. "We're also in interstellar space — a high-radiation environment that no spacecraft have flown in before."

The glitch has to do with Voyager 1's attitude articulation and control system, or AACS, which keeps the spacecraft and its antenna in the proper orientation. And the AACS seems to be working just fine, since the spacecraft is receiving commands, acting on them and sending science data back to Earth with the same signal strength as usual. Nevertheless, the AACS is sending the spacecraft's handlers junk telemetry data.

The NASA statement does not specify when the issue began or how long it has lasted.

The agency says that Voyager personnel will continue to investigate the issue and attempt to either fix or adapt to it. That's a slow process, since a signal from Earth currently takes 20 hours and 33 minutes to reach Voyager 1; receiving the spacecraft's response carries the same delay.

The twin Voyager 2 probe, also launched in 1977, is behaving normally, NASA said. The power the twin spacecraft can produce is always falling, and mission team members have turned some components off to save juice — measures they hope will keep the probes working through at least 2025.

"There are some big challenges for the engineering team," Dodd said. "But I think if there's a way to solve this issue with the AACS, our team will find it."

Email Meghan Bartels at mbartels@space.com or follow her on Twitter @meghanbartels. Follow us on Twitter @Spacedotcom and on Facebook.

NASA's Lucy asteroid mission launching this weekend will carry on a deep-space tradition of bringing a commemorative plaque along for the cosmic ride.

Set to launch no earlier than Saturday (Oct. 16), the Lucy spacecraft is expected to swing by at least eight asteroids during its lifetime and its plaque acts as a nod to space history with a twist. Instead of hailing aliens, as previous NASA messages aimed to do, the Lucy plaque will serve as a reminder of the value of space exploration to humanity's own descendants.

"This time capsule contains messages from prominent members of our society; individuals who have asked us to contemplate the state of the human condition as well as our place in the universe," NASA said in a statement. "These thoughtful leaders were asked to provide words of advice, words of wisdom, words of joy, and words of inspiration to those who may read this plaque in the distant future."

Related: Meet the 8 asteroids NASA's Lucy spacecraft will visit

Mission principal investigator Hal Levison told Space.com that the Lucy plaque is meant to be a deliberate nod to the Pioneer 10 and 11 spacecraft, and Voyager 1 and 2 spacecraft, which all carried plaques far out in the solar system after launches in the 1970s. (Voyager 1 and 2 continue to deliver science results from interstellar space, but may fall silent in a few years as power supplies diminish — the same fate that the Pioneers met.)

"I was in middle school when the Pioneers launched, and in high school when the Voyagers were launched, and I remember really feeling motivated and inspired by those plaques," Levison told Space.com.

To him, he added, the Pioneer and Voyager plaques reduced the separation between living on Earth and exploring the galaxy, especially as they had messages from humanity to any extraterrestrials who may come across them. 

The Lucy plaque — which will stay inside the solar system — is made not for aliens, but for future humans. The mission team, Levison said, "could imagine some [future] astroarchaeologists flying around the solar system, picking up junk, trying to figure out what we were like."

Related: NASA's Lucy asteroid mission will explore mysteries of early solar system

The plaque includes words from a spectrum of individuals, including Nobel Laureates in literature and United States poet laureates. All four members of the famous 1960s band The Beatles, as well as associated artist Yoko Ono, are also included; the Lucy mission is indirectly named for their hit song, "Lucy in the Sky With Diamonds."

The official Lucy website has a list of the messages as well as an image of the plaque, and you can also hear from some of the message selectees in this NASA video. 

A selection of the plaque quotes include:

• "When you've seen beyond yourself, then you may find peace of mind is waiting there." — George Harrison, The Beatles lead guitarist, who died in 2001. 
• "Blessed be the people who see / The dream in the bones of Lucy: / That the worlds braved by humankind / Be worlds that leave us humans kind …" — excerpt from Amanda Gorman, Black poet, activist and National Youth Poet Laureate, who recently spoke at U.S. President Joe Biden's inauguration.
• "Remember the earth whose skin you are: red earth, black earth, yellow earth, white earth, brown earth, we are earth." — excerpt from Joy Harjo, member of the Muscogee Nation and United States poet laureate.

There will be plenty of time for future humans to catch up to Lucy. The mission will survey the Trojan asteroids that share Jupiter's orbit, which have never been seen up close. After Lucy's primary mission ends, the spacecraft is expected to remain in orbit between the Trojans and Earth for "at least hundreds of thousands, if not millions of years," NASA said.

Reporting contributed by Space.com senior writer Meghan Bartels. Follow Elizabeth Howell on Twitter @howellspace. Follow us on Twitter @Spacedotcom and on Facebook.

No probe has gotten a good view of Jupiter's largest moon since 2000, when NASA's Galileo spacecraft swung past the strange world, which is the largest moon in the whole solar system. But on Monday (June 7),  at 1:35 p.m. EDT (1735 GMT), NASA's Juno spacecraft will skim just 645 miles (1,038 kilometers) above Ganymede's surface, gathering a host of observations as it does so.

"Juno carries a suite of sensitive instruments capable of seeing Ganymede in ways never before possible," principal investigator Scott Bolton, a space scientist at the Southwest Research Institute in San Antonio, said in a NASA statement. "By flying so close, we will bring the exploration of Ganymede into the 21st century."

Related: Photos of Ganymede, Jupiter's largest moon

Ganymede is a fascinating world for scientists. Despite its status as a moon, it's larger than the tiny planet Mercury and is the only moon to sport a magnetic field, a bubble of charged particles dubbed a magnetosphere. Until now, the only spacecraft to get a good look at Ganymede were NASA's twin Voyager probes in 1979 and the Galileo spacecraft, which flew past the moon in 2000.

The massive Jovian moon will be a main target of the European Space Agency's Jupiter Icy Moons Explorer mission, known as JUICE, which is due to launch next year and arrive in the Jupiter system in 2029. But that's a long time to wait, and Juno, which launched in 2011, carries significantly more powerful technology than the Voyagers and Galileo spacecraft did.

So scientists are thrilled to make use of the Juno opportunity. During the flyby, several of the spacecraft's instruments will observe Ganymede, including three different cameras, radio instruments, the Ultraviolet Spectrograph (UVS), the Jovian Infrared Auroral Mapper (JIRAM) instruments and the Microwave Radiometer (MWR).

That last instrument's measurements are particularly intriguing for scientists, who hope to use them to identify the different ingredients in the lighter and darker patches of Ganymede's ice shell.

And among the cameras studying the moon will be, of course, the same JunoCam that has snapped such stunning portraits of the gas giant throughout the mission. However, because the icy moon will appear and fade in just 25 minutes, mission scientists expect the instrument will be able to take only five images of Ganymede during the encounter.

But despite the excitement of the unusual moon flyby, Juno scientists can't lose sight of a milestone coming close on the heels of the Ganymede investigation, when the spacecraft makes another flyby of its usual target, Jupiter itself.

"Literally every second counts," Matt Johnson, Juno mission manager at JPL, said in the same statement. "On Monday, we are going to race past Ganymede at almost 12 miles per second (19 kilometers per second). Less than 24 hours later, we're performing our 33rd science pass of Jupiter — screaming low over the cloud tops, at about 36 miles per second (58 kilometers per second).

That means Juno will zoom by Ganymede at a speed of about 43,200 mph (69,523 kph) and then whip around Jupiter at a whopping 129,600 mph (208,571 kph). But Juno's ready for it, Johnson said.

"It is going to be a wild ride."

Email Meghan Bartels at mbartels@space.com or follow her on Twitter @meghanbartels. Follow us on Twitter @Spacedotcom and on Facebook.

Plasma has been part of Voyager 1's mission from its launch — the spacecraft discovered lightning strikes in Jupiter's atmosphere and studied how the solar wind tapered off in the outer solar system.

And since 2012, scientists have turned the spacecraft's instruments upon a completely unexplored part of distant space. That's when Voyager 1 crossed the heliopause, where the solar wind — the constant stream of charged particles that flows off the sun — is no longer strong enough to hold back the interstellar medium that surrounds our little neighborhood. Since 2012, as Voyager 1 has drifted ever farther from the sun, the spacecraft has measured the plasma around it.

Voyager at 40: 40 Photos from NASA's epic 'grand tour' mission

This part of the interstellar medium is, mostly, quiet. "It's very faint and monotone, because it is in a narrow frequency bandwidth," Stella Koch Ocker, a doctoral student at Cornell University who led the new research, said in a statement. "We're detecting the faint, persistent hum of interstellar gas."

But every few years, the solar wind pushes back. Voyager 1 picks up those events as shockwaves. "In the case of a solar outburst, it's like detecting a lightning burst in a thunderstorm," senior author James Cordes, an astronomer at Cornell, said in the same statement. "Then it's back to a gentle rain." 

For a time, scientists thought those shocks were the only way that Voyager 1 could measure the density of plasma out there.

Related: What spacecraft will enter interstellar space next?

But now that scientists have heard this unexpected hum, they can track the interstellar medium between shocks, which can help them understand much more about a largely undiscovered expanse of space. Ocker believes there's much more low-level activity in the interstellar medium than scientists previously thought.

"Now we know we don't need a fortuitous event related to the sun to measure interstellar plasma," Shami Chatterjee, a Cornell astronomer, said in the same statement. "Regardless of what the sun is doing, Voyager is sending back detail. The craft is saying, 'Here's the density I'm swimming through right now. And here it is now. And here it is now. And here it is now.' Voyager is quite distant and will be doing this continuously."

Voyager 1 and its twin, Voyager 2, will sail away to the stars for time immemorial. But for scientists here on Earth, the spacecraft's days are numbered. Sometime within this decade, the spacecraft's plutonium power sources will finally run dry. 

In the meantime, scientists are savoring every last bit of data that trickles back. "It's the engineering gift to science that keeps on giving," Ocker said.

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Fifteen years after launching from Earth at a record speed, and six years since it became the first-ever spacecraft to fly by Pluto, NASA's New Horizons is about to reach a mile marker that only four other robotic probes in history have surpassed.

On Saturday (April 17) at 8:42 p.m. EDT (0042 GMT April 18), New Horizons will reach 50 AU (astronomical units) from the sun — or 50 times the distance the Earth is from the sun. That is 4.65 billion miles (7.5 billion kilometers). At 50 AU, it will take more than 6.5 hours for signals sent from New Horizons to reach Earth, and that is while traveling at the speed of light.

Destination Pluto: NASA's New Horizons mission in pictures

"I just think of the enormity of it," Alan Stern, New Horizons principal investigator at the Southwest Research Institute in Boulder, Colorado, said in an interview with collectSPACE.com. "It hasn't been done in a generation, since the Voyagers crossed these distances, and we're the only spacecraft out there in the outer heliosphere and the Kuiper Belt."

Way out there

New Horizons is the fifth most distant spacecraft from Earth.

Pioneer 10, which was launched in 1972 and was the first probe to pass through the asteroid belt and to fly by Jupiter, reached 50 AU on Sept. 22, 1990. Today, it is approximately 129 AU from Earth.

Its sister ship, Pioneer 11, reached 50 AU a year later in 1991. It was launched in 1973 and in addition to flying by Jupiter, was the first to make direct observations of Saturn. It is now about 105 AU from Earth.

NASA launched Voyager 1 on Sept. 5, 1977, 16 days after its twin, Voyager 2. Voyager 1 studied Jupiter and Saturn, while Voyager 2 also encountered Uranus and Neptune. Voyager 1 today is 152 AU from Earth. Voyager 2 is at 127 AU. While Pioneer 10 and Pioneer 11 ceased operations years ago, both Voyagers remain active today.

The Pioneers and the Voyagers are so far out today that none of them are the nearest probe to New Horizons. NASA's Juno spacecraft, in orbit around Jupiter, is at this point closer.

"In the very distant future, we will be so far from everybody else that we will be closer to the Voyagers and the Pioneers, but we will never pass them because three of the four are going faster than us," said Stern. "Right now, we are almost 100 AU from Voyager 1."

To underscore how far Voyager 1 had traveled, NASA pointed the probe's camera back toward the inner solar system in 1990 when it was approximately 40.11 AU from Earth. The resulting mosaic image, now known as the "Family Portrait," captured six planets — Venus, Earth, Jupiter, Saturn, Neptune and Uranus — as just a few pixels of light each.

At 50 AU from the sun, New Horizons could not do the same.

"The math tells us that would burn out our camera because we would be pointed at the sun," Stern said, noting that even at such great a distance, the sun remains too bright for its long-range reconnaissance imager, which was calibrated for the dimly lit encounter with Pluto. "So we don't want to do that until we are past the Kuiper Belt years from now."

Instead, Stern and his team pointed New Horizons toward Voyager 1, marking the first time that a spacecraft in the Kuiper Belt photographed the location of an even more distant spacecraft now traveling through interstellar space.

"Of course, we didn't see Voyager 1 because it is too faint, but we imaged the star field," Stern told collectSPACE. "We looked with the camera to where the farthest spacecraft is and took a picture of that star field from our position in the Kuiper Belt. It is just hauntingly beautiful to me, even though it is just a picture of stars."

"This is an homage to Voyager's pioneering mission, in addition to marking what we are doing," he said.

Voyager at 40: 40 photos from NASA's epic 'Grand Tour' mission

Over the hill

More than just a round number milestone, reaching 50 AU means that everything New Horizons does now is exceeding its planned design lifespan.

"One of the first things you do when designing a spacecraft is set requirements, and one we had to set was what the maximum distance was we were designing the spacecraft to operate at," said Stern. "Now, you always build in margins so you can do better, but we had to have some number so if we crossed that goal line, we could declare victory — that the spacecraft had met its design objectives."

"That goal line was 50 AU," said Stern.

New Horizons flew by Pluto, returning the first close-up look at the world and its moons, in July 2015, when the spacecraft was 39.2 AU from the sun. Then, on New Year's Day 2019, New Horizons made the farthest flyby in history (to date), capturing the first close-up observations of a small Kuiper Belt object ("Arrokoth") at a distance of 43.4 AU from the sun.

"We're still getting data back from that flyby," said Stern. "Meanwhile, as we fly across the Kuiper Belt, we're doing three other things: we're studying the heliospheric environment, the plasma, the dust and the gas; we're studying other Kuiper Belt objects, we know have more than 30 that we have observed in ways you cannot from Earth or from any other spacecraft; and we're using the Subaru telescope in Hawaii, which is one of the largest telescopes in the world, to find new Kuiper Belt objects to study and hoping we find a flyby target, because we still have fuel in the tank and are capable of doing another flyby."

The hope is to find another target before New Horizons runs out of power. Though it draws its electricity from a nuclear battery (a radioisotope thermoelectric generator, or RTG), its plutonium power supply generates 33 watts less every decade. By the late 2030s, when New Horizons will be at or near 100 AU from the sun, it may be too low on power to operate.

Even if New Horizons does not make it to 100 AU, Stern is impressed with how far the mission has gone and even more so with how much its team has been able to achieve.

"When the Voyagers flew, their team was 450 people. New Horizons is doing this on about 50 bellybuttons, so about 10 times smaller," he said.

"When I think about what our team has accomplished over these 15 years with one spacecraft and no backup, going all the way out there to study Pluto for the first time, the Kuiper Belt for the first time and now pass the 50 AU marker where it was designed to be its maximum distance, it just sounds like science fiction to me," said Stern. "I have to pinch myself that this group of people were actually able to do this thing, it is so much larger than life."

Follow collectSPACE.com on Facebook and on Twitter at @collectSPACE. Copyright 2021 collectSPACE.com. All rights reserved.

What if one mission could study the gravitational waves triggered by some of the most violent events in the universe — on the way to observing the least-known planets of our solar system?

Planetary scientists are desperate for a new probes to Uranus and Neptune, since these ice giant worlds haven't been visited since the Voyager mission flybys of the late 1980s. And while such a spacecraft would unearth a treasure trove of information about these solar system siblings, it could also peer much deeper into the universe, scientists say in a new analysis: By carefully monitoring variations in the radio signals from one or more such spacecraft, astronomers could potentially see the ripples in gravity caused by some of the most violent events in the universe.

Related: Voyager at 40: 40 Photos from NASA's epic 'grand tour' mission

Ice, ice baby

Poor Uranus and Neptune. The only close-up images we have of those outer worlds come to us from the Voyager 2 spacecraft, which swung by those planets on its "Grand Tour" in the late 1980s. Since then, we've sent probes to Mercury, missions to Jupiter and Saturn (including landing on the latter's moon Titan), collected samples of asteroids and comets, and launched rover after rover to Mars.

But not Uranus or Neptune. Those worlds, now known as "ice giants" because water and ammonia ices dominate their composition, sit lonely in the outer fringes of our celestial neighborhood. There are no other worlds in the solar system quite like them, and an entire generation of planetary scientists have been able to study them  with only ground-based telescopes and occasional glimpses from the Hubble Space Telescope.

Some of that delay has been out of our hands. Even Neptune at its closest sits over 2.7 billion miles (4.3 billion kilometers) away from the Earth.The extreme distance to Neptune and Uranus makes it incredibly hard to launch payloads there.

But an opportunity is coming soon, window during which Jupiter lines up just right to offer a much-needed velocity-boosting gravitational assist and cut travel time to the outer system. If we were to launch a mission in the early 2030s on a sufficiently powerful rocket, like NASA's Space Launch System, a mission could reach Jupiter in a little less than two years for that speed boost. From there, a single spacecraft could separate into two components, one headed for Uranus (reaching it in 2042) and another for Neptune (achieving orbit a couple years after that).

Once in place, if luck prevails, those orbiters could maintain their station for over a decade, as the famed Cassini mission did at Saturn.

A shift to the left

During the long cruise to those icy destinations, those same space probes could also offer insight into a very different type of science, that of gravitational waves, as detailed in a paper recently uploaded to the preprint server arXiv.org and submitted to the Monthly Notices of the Royal Astronomical Society Letters.

During the course of the flight, scientists and technicians on the ground would constantly have to communicate with the spacecraft, updating its trajectory and checking its status. And conversely, the spacecraft would constantly radio back information to the Earth.

Light waves bouncing back and forth along an extremely long path.

Sound familiar? On Earth, physicists reflect laser beams along miles-long tracks to measure passing gravitational waves. As the waves (which are ripples in the fabric of spacetime itself) pass through the Earth, they distort objects, compressing and stretching them in alternating series. Inside the detector, these waves subtly change the length between distant mirrors, affecting the path of light in the gravitational wave observatories by a minute amount (usually less than the width of an atom).

For radio communications from a distant space mission back to Earth, the effect is similar. If a gravitational wave passes through the solar system, it would change the distance to the spacecraft in a regular way, causing the probe to be ever-so-slightly closer to us, then farther away, then closer again. If the spacecraft was sending a transmission the entire cruise, we would see a resulting Doppler shift in the frequency of its radio communication. Having two such spacecraft acting at once would give astronomers sharper observations of that shift.

In other words, these far-flung space probes could do double-duty as the largest gravitational wave observatories in the world.

The greater universe

The biggest technological hurdle is the ability to measure the frequency of the spacecraft's radio communications to an incredibly high precision. According to the recent research, our ability to measure this must be at least 100 times better than we could achieve for the Cassini mission to Saturn.

That sounds like a lot, but it's been decades since Cassini was designed, and we've been improving our communication technologies the whole time. And physicists are currently designing their own space-based gravitational wave detectors, like the Laser Interferometer Space Antenna (LISA), which will require similar technology anyway. Since an ice giant mission is still almost a decade away, we could pour even more resources into developing the necessary technology.

If we can crack that level of sensitivity, then the extreme length of this gravitational wave detector "arm" (literally billions of times longer than our current detectors) could reveal a variety of extreme events in the universe. Due to its incredible length, this "ice giant observatory" would be sensitive to an entirely different class of events than what we can observe today. According to the research, during the lifespan of such a mission, the probes are likely to detect a few dozen mergers of black holes with extreme mass differences, and at least one merger of a supermassive black hole. These are events that we simply have not observed, and cannot observe, with current gravitational wave detectors.

Oh, and we would also get to learn about Uranus and Neptune.

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Von Littrow never saw his idea come to fruition. Still, long after he proposed his ambitious plan, we haven't stopped our attempts to contact extraterrestrial life.

So, what messages have we sent to aliens?

Related: Are aliens ignoring us?

Radio actualized the quest to declare Earth's existence. In 1962, Soviet scientists aimed a radio transmitter at Venus and saluted the planet in Morse code. This introduction, the first of its kind, included three words: Mir (Russian for "peace" or "world"), Lenin and SSSR (the Latin alphabet acronym for the Cyrillic name of the Soviet Union). The message was considered largely symbolic, according to a 2018 article published in the International Journal of Astrobiology. More than anything, it was a test run for a brand-new planetary radar, a technology which sends radio waves into space, with the primary goal of observing and mapping objects in the solar system.

In terms of distance, the next attempt to reach ET was far more ambitious. In 1974, a team of scientists, including astronomers Frank Drake and Carl Sagan, transmitted a radio message from the Arecibo Observatory in Puerto Rico toward Messier 13, a cluster of stars about 25,000 light-years away. The image, sent in binary code, depicted a human stick figure, a double-helix DNA structure, a model of a carbon atom and a diagram of a telescope. 

"The Arecibo message tried to give a snapshot of who we are as human beings in the language of math and science," Douglas Vakoch, a psychologist and the president of Messaging Extraterrestrial Intelligence (METI) International told Live Science. 

The Arecibo message was, quite literally, a shot in the dark. It will take around 25,000 light-years to reach Messier 13 — at which point, the star cluster will have moved, according to the Cornell University Department of Astronomy. Hypothetical aliens might still be able to detect the signal as it whizzes past — it has 10 million times the intensity of radio signals from our sun. (The sun emits a wide spectrum of electromagnetic radiation — from ultraviolet to radio.) But that's unlikely, said Seth Shostak, an astronomer at the Search for Extraterrestrial Intelligence (SETI) Institute.

"It was, in some sense, the most powerful message," Shostak told Live Science. "It's like a giant billboard on [U.S. interstate] I-5, but it's off in a field somewhere."

More recently, radio has been used to transmit everything from art to advertisements. In 2008, Doritos beamed its own ad to a solar system in the Ursa Majoris constellation, around 42 light-years away, according to the article in the International Journal of Astrobiology. In 2010, a message written in Klingon, a language used by fictional aliens in the "Star Trek" universe,  invited real aliens to attend a Klingon opera in Holland. 

We haven't relied only on radio to communicate; we've also launched spacecraft containing artifacts from Earth, in the hope that they'll eventually be scooped out of interstellar space by intelligent life-forms. Voyagers 1 and 2 were launched in 1977 to explore the outer reaches of our solar system and interstellar space. Each carries a Golden Record containing music, ambient sounds from Earth and 116 images of our planet and solar system. 

The Voyager spacecraft are still chugging through interstellar space, waiting to be discovered. But the chances of that happening? "Zero," said Sheri Wells-Jensen, a linguist at Bowling Green State University in Ohio who specializes in extraterrestrial intelligence. 

"It was just a beautiful and poetic, lovely, brave attempt that really did sum up kind of the best of us, even if it's pointless in terms of actually communicating," Wells-Jensen told Live Science. 

Experts agree that the likelihood that any of these attempts will reach alien civilizations is low. That outcome depends, of course, on whether there is  alien life in our star system. But that life in question would also have to be listening closely for radio signals and understand enough about math and science to interpret our messages. Finally, the messages we've sent tend to assume that these aliens sense the universe in the same way we do: with hearing and vision. 

But that doesn't mean all of these messages are pointless. "We're looking. Why wouldn't they be looking?" Wells-Jensen told Live Science. And if our messages are unintelligible to these hypothetical beings? That's OK. "I think the most important thing that we've ever said is just that we exist," Wells-Jensen said.

Originally published on Live Science.

OAC, a manufacturing firm centered on the colonization of space, discussed Voyager Station during a video press junket late last month. The Jan. 29 "First Assembly" virtual event served as an update for interested investors, marketing partners and enthusiastic vacationers hoping to someday book a room aboard the rotating Voyager Station.

The project's roots go back a number of years. 

In pictures: Private space stations of the future

John Blincow established The Gateway Foundation in 2012. The organization's plans include jumpstarting and sustaining a robust and thriving space construction industry, first with the Voyager Station and The Gateway commercial space station — "important first steps to colonizing space and other worlds," the foundation's website states. OAC was founded by the Gateway Foundation team in 2018 as a way to help make these dreams come true. 

The hour-long Jan. 29 presentation and Q&A session was hosted by OAC medical advisor Shawna Pandya and streamed live on the company's YouTube channel. During the event, the space construction company revealed its schedule for the next chapter of human space exploration. 

Its team of skilled NASA veterans, pilots, engineers and architects intends to assemble a "space hotel" in low Earth orbit that rotates fast enough to generate artificial gravity for vacationers, scientists, astronauts educators and anyone else who wants to experience off-Earth living.

As a multi-phase endeavor requiring funds to realize the dream, OAC is now officially open for private investors to purchase a stake in the company at $0.25 per share, until April 1, 2021. 

Voyager Station is patterned after concepts imagined by legendary rocket scientist Wernher von Braun, one of the main orchestrators of NASA's Apollo program. The 650-foot-wide (200 meters) wheel-shaped habitat will spin with an angular velocity high enough to create moon-like levels of artificial gravity for occupants.

Lunar legacy: 45 Apollo moon mission photos

If realized, Voyager would become the biggest human-made structure in space, fully equipped to accommodate up to 400 people. Assembly is scheduled to begin around 2025, Gateway Foundation representatives said. 

This shining technological ring will feature amenities ranging from themed restaurants, viewing lounges, movie theaters and concert venues to bars, libraries, gyms, and a health spa.

Voyager will house 24 integrated habitation modules, each of which will be 65 feet long and 40 feet wide (20 by 12 meters). At near-lunar gravity, the rotating resort will have functional toilets, showers, and allow jogging and jumping in fun and novel ways.

But before the station can start spinning, its builders must establish the necessary orbital infrastructure and create smaller structures to test the concept. 

Blincow explained during the Jan. 29 event that the current plan is to build the rotating space station in stages, beginning with a small-scale prototype station, in addition to a free-flying microgravity facility, both using Voyager components. 

"This will be the next industrial revolution," Blincow said.

Eventually, a Structure Truss Assembly Robot (STAR) will fabricate the frame of the Voyager and Gateway stations in orbit. Prior to that happening, however, a smaller, ground-based prototype, known as DSTAR, will test the technology here on Earth. 

OAC's truss assembly robot stands to be the first to build a space station in low Earth orbit and will serve as "the structural backbone of future projects in space," OAC fabrication manager Tim Clements said during the event. 

Currently, the machine is undergoing commissioning and shipping. It will then be completed and tested in California.

"The prototype will produce a truss section roughly 300 feet [90 m] in length in under 90 minutes," Clements revealed during the live-streamed event. "DSTAR weighs almost 8 tons in mass, consisting of steel, electrical and mechanical components."

OAC is also creating a robotic observer drone for remote viewing via a virtual reality headset as its first in-house development project. 

"It's going to be our eyes on the job site," said Tim Alatorre, Gateway Foundation executive team member one of the station's designers. "The observer drone operates in a support function. It can perch on existing craft. It can also be fully reusable and can fly and have a free-flight mode on extended missions."

Long before Voyager Station can start accommodating guests, OAC needs to test both building a station in low Earth orbit and prove the viability of stable artificial gravity in space. The company plans to construct a prototype gravity ring that will measure 200 feet (61 m) in diameter and will be engineered to spin up to create artificial gravity near Mars' level, which is about 40% that of Earth.

"The gravity ring is going to be a key technology demonstration project that we plan to build, assemble and operate in low Earth orbit in just a few years' time," said OAC co-founder Jeff Greenblatt. "The company also plans to use an orbital version of the DSTAR called the PSTAR, which stands for Prototype Structural Truss Assembly Robot."

This gravity ring will act as a "near-term demonstrator," which will take two to three years to build and launch. Once installed in orbit, its assembly will take just three days. This structure will act as the company’s test base for many of the technologies to be used to build Voyager Station.

"We haven't seen an explosion of commercial activity in space," Alatorre said. "The cost has been about $8,000 per kilogram [$3,600 per lb.] for a long time. But with the Falcon 9, you can do it for less than $2,000. And as Starship comes online, it will only cost a few hundred dollars." (These were references to SpaceX launchers — the company's workhorse Falcon 9 rocket and its Starship Mars vehicle, which is in development.)

"Microgravity is just brutal on our bodies," Alatorre added "We need artificial gravity — a mechanism to give us a dosage of gravity to give us the ability to live long-term in space." 

Related: Weightlessness and its effects on astronauts

The planned gravity ring may also become a research platform for international space agencies and private aerospace firms interested in the effects of partial artificial gravity on both non-living and living systems, OAC representatives said.

"This will give researchers an unprecedented opportunity to access that intermediate gravity regime," Greenblatt said. "This will then pave the way for OAC to build larger, more complex structures in space, which is obviously necessary if we're going to get to the point of building Voyager Station and other larger structures beyond."

Looking into the future, government and private companies will be allowed to use the Voyager modules for lunar training missions and beyond, providing a launch pad for entrepreneurs to develop and market tourist activities in space.

"We don't want the Voyager experience to be like being in an attack submarine in combat, so we're [building] for comfort," said Tom Spilker, OAC's chief technology officer and vice president of engineering and space systems design. "It's a bit smaller than the length of the U.S. Capitol building."

"Despite the seemingly endless list of luxury amenities, there will also be airlocks for visitors," Spilker added. "So anyone who can afford a space hotel can go on a private spacewalk, where the only thing between you and the universe is a faceplate."

Correction: A previous version of this story listed Gateway Foundation executive team member Tim Alatorre as the lead designer of the Voyager station project. He is one of the designers. 

Follow us on Twitter @Spacedotcom and on Facebook.

Those artifacts are the engraved "Golden Records" strapped to NASA's twin Voyager spacecraft, which have passed into interstellar space. Although the spacecraft will likely fall silent in a few years, the records will remain. Nick Oberg, a doctoral candidate at the Kapteyn Astronomical Institute in the Netherlands, and a colleague wanted to calculate which (if any) stars the two Voyager spacecraft may encounter in the long future of our galaxy.

But the models let them forecast much, much farther into the future. Oberg presented their work at the 237th meeting of the American Astronomical Society, held virtually due to the coronavirus pandemic, on Jan. 12, where he spun a tale of the long future of the twin Voyagers and their Golden Records.

Related: Pale Blue Dot at 30: Voyager 1's iconic photo of Earth from space reveals our place in the universe

NASA launched Voyager 1 and Voyager 2 in 1977 to trek across the solar system. On each was a 12-inch (30 centimeters) large gold-plated copper disk. The brainchild of famed astronomer Carl Sagan, the Golden Records were engraved with music and photographs meant to represent Earth and its humans to any intelligent beings the spacecraft meet on their long journeys. Both spacecraft visited Jupiter and Saturn, then the twins parted ways: Voyager 1 studied Saturn's moon Titan while Voyager 2 swung past Uranus and Neptune. 

In 2012, Voyager 1 passed through the heliopause that marks the edge of the sun's solar wind and entered interstellar space; in 2018, Voyager 2 did so as well. Now, the two spacecraft are chugging through the vast outer reaches of the solar system. They continue to send signals back to Earth, updating humans about their adventures far beyond the planets, although those bulletins may cease in a few years, as the spacecraft are both running low on power.

But their journeys are far from over.

Oberg and his colleague combined tracking the Voyagers' trajectories forward with studying the environments the spacecraft will fly through to estimate the odds of the Golden Records surviving their adventures while remaining legible. The result is a forecast that stretches beyond not just humanity's likely extinction, but also beyond the collision of the Milky Way with the neighboring Andromeda galaxy — beyond even the extinction of most stars.

Related: The Golden Record in pictures: Voyager probes' message to space explained

Milky Way sightseein

Unsurprisingly, the duo's research ambitions didn't start out quite so vast. The new research was inspired by the release of the second batch of data from the European Space Agency's spacecraft Gaia, which specializes in mapping more than a billion stars super precisely.

"Our original goal was to determine with a very high precision which stars the Voyagers might one day closely encounter using the at the time newly released Gaia catalog of stars," Oberg said during his presentation. So he and his co-author began by tracing the Voyagers' journeys to date and projecting their trajectories out into the future.

But don't get excited for any upcoming milestones. Not until about 20,000 years from now will the Voyagers pass through the Oort cloud — the shell of comets and icy rubble that orbits the sun at a distance of up to 100,000 astronomical units, or 100,000 times the average Earth-sun distance — finally waving goodbye to its solar system of origin.

"At that point for the first time the craft will begin to feel the gravitational pull of other stars more strongly than that of our own sun," Oberg said.

It's another 10,000 years before the spacecraft actually come near an alien star, specifically a red dwarf star called Ross 248. That flyby will occur about 30,000 years from now, Oberg said, although it might be a stretch to say that the spacecraft will pass by that star. "It's actually more like Ross 248 shooting past the nearly stationary Voyagers," he said.

By 500 million years from now, the solar system and the Voyagers alike will complete a full orbit through the Milky Way. There's no way to predict what will have happened on Earth's surface by then, but it's a timespan on the scale of the formation and destruction of Pangaea and other supercontinents, Oberg said.

Throughout this galactic orbit, the Voyager spacecraft will oscillate up and down, with Voyager 1 doing so more dramatically than its twin. According to these models, Voyager 1 will travel so far above the main disk of the galaxy that it will see stars at just half the density as we do.

Odds of destruction

The same difference in vertical motion will also shape the differing odds each spacecraft's Golden Record has of survival.

The records were designed to last, meant to survive perhaps a billion years in space: beneath the golden sheen is a protective aluminum casing and, below that, the engraved copper disks themselves. But to truly understand how long these objects may survive, you have to know what conditions they'll experience, and that means knowing where they will be.

Specifically, Oberg and his colleague needed to know how much time the spacecraft would spend swathed in the Milky Way's vast clouds of interstellar dust, which he called "one of the few phenomena that could actually act to damage the spacecraft."

It's a grim scenario, dust pounding into the Voyagers at a speed of a few miles or kilometers per second. "The grains will act as a steady rain that slowly chips away at the skin of the spacecraft," Oberg said. "A dust grain only one-thousandth of a millimeter across will still leave a small vaporized crater when it impacts."

Voyager 1's vertical oscillations mean that spacecraft will spend more time above and below the plane of the galaxy, where the clouds are thickest. Oberg and his colleague simulated thousands of times over the paths of the two spacecraft and their encounters with the dust clouds, modeling the damage the Golden Records would incur along the way.

That work also requires taking into consideration the possibility that a cloud's gravity might tug at one of the Voyagers' trajectories, Oberg said. "The clouds have so much mass concentrated in one place that they actually may act to bend the trajectory of the spacecraft and fling them into new orbits — sometimes much farther out, sometimes even deeper toward the galactic core."

Both Golden Records have good odds of remaining legible, since their engraved sides are tucked away against the spacecraft bodies. The outer surface of Voyager 1's record is more likely to erode away, but the information on Voyager 2's record is more likely to become illegible, Oberg said.

"The main reason for this is because the orbit that Voyager 2 is flung into is more chaotic, and it's significantly more difficult to predict with any certainty of exactly what sort of environment it's going to be flying through," he said.

But despite the onslaught and potential detours, "Both Golden Records are highly likely to survive at least partially intact for a span of over 5 billion years," Oberg said.

Related: Photos from NASA's Voyager 1 and 2 probes

After the Milky Way's end

After those 5 billion years, modeling is tricky. That's when the Milky Way is due to collide with its massive neighbor, the Andromeda galaxy, and things get messy. "The orderly spiral shape will be severely warped, and possibly destroyed entirely," Oberg said. The Voyagers will be caught up in the merger, with the details difficult to predict so far in advance.

Meanwhile, the vicarious sightseeing continues. Oberg and his colleague calculated that in this 5-billion-year model-friendly period, each of the Voyagers likely visits a star besides our sun within about 150 times the distance between Earth and the sun, or three times the distance between the sun and Pluto at the dwarf planet's most distant point.

Precisely which star that might be, however, is tricky — it may not even be a star we know today.

"While neither Voyager is likely to get particularly close to any star before the galaxies collide, the craft are likely to at least pass through the outskirts of some [star] system," Oberg said. "The very strange part is that that actually might be a system that does not yet exist, of a star that has yet to be born."

Such are the perils of working on a scale of billions of years.

From here, the Voyagers' fate depends on the conditions of the galactic merger, Oberg said.

The collision itself might kick a spacecraft out of the newly monstrous galaxy — a one in five chance, he said — although it would remain stuck in the neighborhood. If that occurs, the biggest threat to the Golden Records would become collisions with high-energy cosmic rays and the odd molecule of hot gas, Oberg said; these impacts would be rarer than the dust that characterized their damage inside the Milky Way.

Inside the combined galaxy, the Voyagers' fate would depend on how much dust is left behind by the merger; Oberg said that may well be minimal as star formation and explosion both slow, reducing the amount of dust flung into the galaxy.

Depending on their luck with this dust, the Voyagers may be able to ride out trillions of trillions of trillions of years, long enough to cruise through a truly alien cosmos, Oberg said.

"Such a distant time is far beyond the point where stars have exhausted their fuel and star formation has ceased in its entirety in the universe," he said. "The Voyagers will be drifting through what would be, to us, a completely unrecognizable galaxy, free of so-called main-sequence stars, populated almost exclusively by black holes and stellar remnants such as a white dwarfs and neutron stars."

It's a dark future, Oberg added. "The only source of significant illumination in this epoch will be supernovas that results from the once-in-a-trillion-year collision between these stellar remnants that still populate the galaxy," he said. "Our work, found on these records, thus may bear witness to these isolated flashes in the dark."

Email Meghan Bartels at mbartels@space.com or follow her on Twitter @meghanbartels. Follow us on Twitter @Spacedotcom and on Facebook.

China has made it to Mars.

The nation's first fully homegrown Mars mission, Tianwen-1, arrived in orbit around the Red Planet today (Feb. 10), according to Chinese media reports.

The milestone makes China the sixth entity to get a probe to Mars, joining the United States, the Soviet Union, the European Space Agency, India and the United Arab Emirates, whose Hope orbiter made it to the Red Planet just yesterday (Feb. 9).

And today's achievement sets the stage for something even more epic a few months from now — the touchdown of Tianwen-1's lander-rover pair on a large plain in Mars' northern hemisphere called Utopia Planitia, which is expected to take place this May. (China doesn't typically publicize details of its space missions in advance, so we don't know for sure exactly when that landing will occur.)

Related: Here's what China's Tianwen-1 Mars mission will do
See more: China's Tianwen-1 Mars mission in photos

An ambitious mission

China took its first crack at Mars back in November 2011, with an orbiter called Yinghuo-1 that launched with Russia's Phobos-Grunt sample-return mission. But Phobos-Grunt never made it out of Earth orbit, and Yinghuo-1 crashed and burned with the Russian probe and another tagalong, the Planetary Society's Living Interplanetary Flight Experiment.

Tianwen-1 (which means "Questioning the Heavens") is a big step up from Yinghuo-1, however. For starters, this current mission is an entirely China-led affair; it was developed by the China National Space Administration (with some international collaboration) and launched atop a Chinese Long March 5 rocket on July 23, 2020.

Tianwen-1 is also far more ambitious than the earlier orbiter, which weighed a scant 254 lbs. (115 kilograms). Tianwen-1 tipped the scales at about 11,000 lbs. (5,000 kg) at launch, and it consists of an orbiter and a lander-rover duo.

These craft will take Mars' measure in a variety of ways. The orbiter, for example, will study the planet from above using a high-resolution camera, a spectrometer, a magnetometer and an ice-mapping radar instrument, among other scientific gear.

The orbiter will also relay communications from the rover, which sports an impressive scientific suite of its own. Among the rover's gear are cameras, climate and geology instruments and ground-penetrating radar, which will hunt for pockets of water beneath Mars' red dirt. 

Occupy Mars: History of robotic Red Planet missions (infographic)

"On Earth, these pockets can host thriving microbial communities, so detecting them on Mars would be an important step in our search for life on other worlds," the Planetary Society wrote in a description of the Tianwen-1 mission.

The lander, meanwhile, will serve as a platform for the rover, deploying a ramp that the wheeled vehicle will roll down onto the Martian surface. The setup is similar to the one China has used on the moon with its Chang'e 3 and Chang'e 4 rovers, the latter of which is still going strong on Earth's rocky satellite.

If the Tianwen-1 rover and lander touch down safely this May and get to work, China will become just the second nation, after the United States, to operate a spacecraft successfully on the Red Planet's surface for an appreciable amount of time. (The Soviet Union pulled off the first-ever soft touchdown on the Red Planet with its Mars 3 mission in 1971, but that lander died less than two minutes after hitting the red dirt.)

The Tianwen-1 orbiter is scheduled to operate for at least one Mars year (about 687 Earth days), and the rover's targeted lifetime is 90 Mars days, or sols (about 93 Earth days).

Bigger things to come?

Tianwen-1 will be just China's opening act at Mars, if all goes according to plan: The nation aims to haul pristine samples of Martian material back to Earth by 2030, where they can be examined in detail for potential signs of life and clues about Mars' long-ago transition from a relatively warm and wet planet to the cold desert world it is today.

NASA has similar ambitions, and the first stage of its Mars sample-return campaign is already underway. The agency's Perseverance rover will touch down inside the Red Planet's Jezero Crater next Thursday (Feb. 18), kicking off a surface mission whose top-level tasks include searching for signs of ancient Mars life and collecting and caching several dozen samples.

Perseverance's samples will be hauled home by a joint NASA-European Space Agency campaign, perhaps as early as 2031.

So we have a lot to look forward to in the coming days and weeks, and many reasons to keep our fingers crossed for multiple successful Red Planet touchdowns.

"More countries exploring Mars and our solar system means more discoveries and opportunities for global collaboration," the Planetary Society wrote in its Tianwen-1 description. "Space exploration brings out the best in us all, and when nations work together everyone wins."

Mike Wall is the author of "Out There" (Grand Central Publishing, 2018; illustrated by Karl Tate), a book about the search for alien life. Follow him on Twitter @michaeldwall. Follow us on Twitter @Spacedotcom or Facebook. 

China has made it to Mars.

The nation's first fully homegrown Mars mission, Tianwen-1, arrived in orbit around the Red Planet today (Feb. 10), according to Chinese media reports.

The milestone makes China the sixth entity to get a probe to Mars, joining the United States, the Soviet Union, the European Space Agency, India and the United Arab Emirates, whose Hope orbiter made it to the Red Planet just yesterday (Feb. 9).

And today's achievement sets the stage for something even more epic a few months from now — the touchdown of Tianwen-1's lander-rover pair on a large plain in Mars' northern hemisphere called Utopia Planitia, which is expected to take place this May. (China doesn't typically publicize details of its space missions in advance, so we don't know for sure exactly when that landing will occur.)

Related: Here's what China's Tianwen-1 Mars mission will do
See more: China's Tianwen-1 Mars mission in photos

An ambitious mission

China took its first crack at Mars back in November 2011, with an orbiter called Yinghuo-1 that launched with Russia's Phobos-Grunt sample-return mission. But Phobos-Grunt never made it out of Earth orbit, and Yinghuo-1 crashed and burned with the Russian probe and another tagalong, the Planetary Society's Living Interplanetary Flight Experiment.

Tianwen-1 (which means "Questioning the Heavens") is a big step up from Yinghuo-1, however. For starters, this current mission is an entirely China-led affair; it was developed by the China National Space Administration (with some international collaboration) and launched atop a Chinese Long March 5 rocket on July 23, 2020.

Tianwen-1 is also far more ambitious than the earlier orbiter, which weighed a scant 254 lbs. (115 kilograms). Tianwen-1 tipped the scales at about 11,000 lbs. (5,000 kg) at launch, and it consists of an orbiter and a lander-rover duo.

These craft will take Mars' measure in a variety of ways. The orbiter, for example, will study the planet from above using a high-resolution camera, a spectrometer, a magnetometer and an ice-mapping radar instrument, among other scientific gear.

The orbiter will also relay communications from the rover, which sports an impressive scientific suite of its own. Among the rover's gear are cameras, climate and geology instruments and ground-penetrating radar, which will hunt for pockets of water beneath Mars' red dirt. 

Occupy Mars: History of robotic Red Planet missions (infographic)

"On Earth, these pockets can host thriving microbial communities, so detecting them on Mars would be an important step in our search for life on other worlds," the Planetary Society wrote in a description of the Tianwen-1 mission.

The lander, meanwhile, will serve as a platform for the rover, deploying a ramp that the wheeled vehicle will roll down onto the Martian surface. The setup is similar to the one China has used on the moon with its Chang'e 3 and Chang'e 4 rovers, the latter of which is still going strong on Earth's rocky satellite.

If the Tianwen-1 rover and lander touch down safely this May and get to work, China will become just the second nation, after the United States, to operate a spacecraft successfully on the Red Planet's surface for an appreciable amount of time. (The Soviet Union pulled off the first-ever soft touchdown on the Red Planet with its Mars 3 mission in 1971, but that lander died less than two minutes after hitting the red dirt.)

The Tianwen-1 orbiter is scheduled to operate for at least one Mars year (about 687 Earth days), and the rover's targeted lifetime is 90 Mars days, or sols (about 93 Earth days).

Bigger things to come?

Tianwen-1 will be just China's opening act at Mars, if all goes according to plan: The nation aims to haul pristine samples of Martian material back to Earth by 2030, where they can be examined in detail for potential signs of life and clues about Mars' long-ago transition from a relatively warm and wet planet to the cold desert world it is today.

NASA has similar ambitions, and the first stage of its Mars sample-return campaign is already underway. The agency's Perseverance rover will touch down inside the Red Planet's Jezero Crater next Thursday (Feb. 18), kicking off a surface mission whose top-level tasks include searching for signs of ancient Mars life and collecting and caching several dozen samples.

Perseverance's samples will be hauled home by a joint NASA-European Space Agency campaign, perhaps as early as 2031.

So we have a lot to look forward to in the coming days and weeks, and many reasons to keep our fingers crossed for multiple successful Red Planet touchdowns.

"More countries exploring Mars and our solar system means more discoveries and opportunities for global collaboration," the Planetary Society wrote in its Tianwen-1 description. "Space exploration brings out the best in us all, and when nations work together everyone wins."

Mike Wall is the author of "Out There" (Grand Central Publishing, 2018; illustrated by Karl Tate), a book about the search for alien life. Follow him on Twitter @michaeldwall. Follow us on Twitter @Spacedotcom or Facebook. 

China has made it to Mars.

The nation's first fully homegrown Mars mission, Tianwen-1, arrived in orbit around the Red Planet today (Feb. 10), according to Chinese media reports.

The milestone makes China the sixth entity to get a probe to Mars, joining the United States, the Soviet Union, the European Space Agency, India and the United Arab Emirates, whose Hope orbiter made it to the Red Planet just yesterday (Feb. 9).

And today's achievement sets the stage for something even more epic a few months from now — the touchdown of Tianwen-1's lander-rover pair on a large plain in Mars' northern hemisphere called Utopia Planitia, which is expected to take place this May. (China doesn't typically publicize details of its space missions in advance, so we don't know for sure exactly when that landing will occur.)

Related: Here's what China's Tianwen-1 Mars mission will do
See more: China's Tianwen-1 Mars mission in photos

An ambitious mission

China took its first crack at Mars back in November 2011, with an orbiter called Yinghuo-1 that launched with Russia's Phobos-Grunt sample-return mission. But Phobos-Grunt never made it out of Earth orbit, and Yinghuo-1 crashed and burned with the Russian probe and another tagalong, the Planetary Society's Living Interplanetary Flight Experiment.

Tianwen-1 (which means "Questioning the Heavens") is a big step up from Yinghuo-1, however. For starters, this current mission is an entirely China-led affair; it was developed by the China National Space Administration (with some international collaboration) and launched atop a Chinese Long March 5 rocket on July 23, 2020.

Tianwen-1 is also far more ambitious than the earlier orbiter, which weighed a scant 254 lbs. (115 kilograms). Tianwen-1 tipped the scales at about 11,000 lbs. (5,000 kg) at launch, and it consists of an orbiter and a lander-rover duo.

These craft will take Mars' measure in a variety of ways. The orbiter, for example, will study the planet from above using a high-resolution camera, a spectrometer, a magnetometer and an ice-mapping radar instrument, among other scientific gear.

The orbiter will also relay communications from the rover, which sports an impressive scientific suite of its own. Among the rover's gear are cameras, climate and geology instruments and ground-penetrating radar, which will hunt for pockets of water beneath Mars' red dirt. 

Occupy Mars: History of robotic Red Planet missions (infographic)

"On Earth, these pockets can host thriving microbial communities, so detecting them on Mars would be an important step in our search for life on other worlds," the Planetary Society wrote in a description of the Tianwen-1 mission.

The lander, meanwhile, will serve as a platform for the rover, deploying a ramp that the wheeled vehicle will roll down onto the Martian surface. The setup is similar to the one China has used on the moon with its Chang'e 3 and Chang'e 4 rovers, the latter of which is still going strong on Earth's rocky satellite.

If the Tianwen-1 rover and lander touch down safely this May and get to work, China will become just the second nation, after the United States, to operate a spacecraft successfully on the Red Planet's surface for an appreciable amount of time. (The Soviet Union pulled off the first-ever soft touchdown on the Red Planet with its Mars 3 mission in 1971, but that lander died less than two minutes after hitting the red dirt.)

The Tianwen-1 orbiter is scheduled to operate for at least one Mars year (about 687 Earth days), and the rover's targeted lifetime is 90 Mars days, or sols (about 93 Earth days).

Bigger things to come?

Tianwen-1 will be just China's opening act at Mars, if all goes according to plan: The nation aims to haul pristine samples of Martian material back to Earth by 2030, where they can be examined in detail for potential signs of life and clues about Mars' long-ago transition from a relatively warm and wet planet to the cold desert world it is today.

NASA has similar ambitions, and the first stage of its Mars sample-return campaign is already underway. The agency's Perseverance rover will touch down inside the Red Planet's Jezero Crater next Thursday (Feb. 18), kicking off a surface mission whose top-level tasks include searching for signs of ancient Mars life and collecting and caching several dozen samples.

Perseverance's samples will be hauled home by a joint NASA-European Space Agency campaign, perhaps as early as 2031.

So we have a lot to look forward to in the coming days and weeks, and many reasons to keep our fingers crossed for multiple successful Red Planet touchdowns.

"More countries exploring Mars and our solar system means more discoveries and opportunities for global collaboration," the Planetary Society wrote in its Tianwen-1 description. "Space exploration brings out the best in us all, and when nations work together everyone wins."

Mike Wall is the author of "Out There" (Grand Central Publishing, 2018; illustrated by Karl Tate), a book about the search for alien life. Follow him on Twitter @michaeldwall. Follow us on Twitter @Spacedotcom or Facebook. 

The Voyager mission has detected a new type of "electron burst," which will provide insights into the mechanisms of flaring stars, a new study reports. 

The bursts occur when cosmic ray electrons — fast-moving particles from far beyond the solar system — are pushed by shock waves generated by solar eruptions. The electrons then accelerate further along cosmic magnetic field lines to incredible speed, study team members said.

"The idea that shock waves accelerate particles is not new," corresponding author Don Gurnett, professor emeritus in physics and astronomy at the University of Iowa, said in a statement. "[But] we detected it in a new realm: the interstellar medium, which is much different than in the solar wind, where similar processes have been observed."

Both Voyager spacecraft are still going strong after 43 years in space, with each regularly sending back science to Earth from their remaining operating instruments. (Voyager 2 flew incommunicado for several months in 2020 due to planned repairs and upgrades to its radio communications facility here on Earth but made contact again in November.)

The first stage to creating the electron bursts happens with coronal mass ejections. These solar eruptions blast huge amounts of superhot plasma into space and create shock waves that move outward through the solar system.

These shock waves accelerate fast-moving cosmic-ray electrons, charged particles that likely originate from distant supernovas. The cosmic rays are further accelerated along magnetic field lines in between stars, in the interstellar medium. 

Voyager at 40: 40 photos from NASA's epic 'grand tour' mission

Eventually, the magnetic field lines propel the cosmic rays to almost the speed of light — nearly 670 times faster than the solar shock waves that first pushed them. (The shock waves move at roughly 1 million mph, or 1.6 million kph, study team members said.)

"Physicists believe these electrons in the interstellar medium are reflected off of a strengthened magnetic field at the edge of the shock wave, and subsequently accelerated by the motion of the shock wave," the University of Iowa said in the same release. "The reflected electrons then spiral along interstellar magnetic field lines, gaining speed as the distance between them and the shock increases."

Voyager 1 and Voyager 2 both detected the electron bursts within days of their acceleration, and somewhat later, the two probes spotted slower, lower-energy plasma wave oscillations through the interstellar medium generated by the electron bursts. 

The twin spacecraft also detected the originating solar shock wave up to a year after the event occurred; the wait time happened because the spacecraft are so far from the sun. Voyager 1 is about 14.1 billion miles (22.7 billion km) away from the sun, and Voyager 2 is about 11.7 billion miles (18.8 billion km) from our star. (The average Earth-sun distance is roughly 93 million miles, or 150 million km.) 

Astronomers hope to better understand how shock waves and cosmic radiation originate from flaring stars. Solar outbursts can generate radiation that poses risks for astronauts on the International Space Station or other destinations, such as the moon (where NASA hopes to land in 2024.) Particularly violent eruptions can also threaten Earth-orbiting satellites and planetary infrastructure like power lines.

The new study was published Wednesday (Dec. 3) in The Astronomical Journal.

Follow Elizabeth Howell on Twitter @howellspace. Follow us on Twitter @Spacedotcom and on Facebook.

A Tai Chi master who has traveled the globe, Curry also created the Klingon martial arts style named Mok'bara and the warrior race's distinctive Bat'leth and Mek'leth weapons.

In honor of Curry's innumerable accomplishments over the course of his illustrious career, a deluxe new coffee table book titled "Star Trek: The Artistry of Dan Curry" (Titan Books, 2020) beams to Earth orbit on Dec. 1. 

Co-written with author Ben Robinson, this 204-page hardback spotlights the achievements of one of "Star Trek's" most valued alumni, with rare concept art, behind-the-scenes stills, and secrets to how Curry and his colleagues created the impressive legacy of special effects magic.

We spoke with Curry regarding this rich retrospective of his time on "Star Trek," what he loved most about the series' starships, how time in the Peace Corps influenced Klingon culture, memories of Gene Roddenberry, and how he helped create the Star Trek Stratocaster guitar.

Space.com: Looking back on your "Star Trek" career, what are some defining moments that stand out?

Dan Curry: The first outstanding moment was my first day walking on "The Next Generation" set. The cast was there in costume and the crew was on the beautiful sets designed by Herman Zimmerman. The outsides of the sets are thin plywood walls with two-by-two wooden frames that support them. When you go from outside the set on the soundstage with its concrete floor, lights, gear, and people hanging around, then walk through a door and suddenly you're in the 24th century.

I asked one of the crew members who the captain was and he said, "Oh, that bald guy over there." Then Patrick [Stewart] came out and delivered his first line.  He was the captain.  I was immediately aware that I was in the presence of a truly great actor.

Space.com: Being such an influential part of four “Star Trek” series, why do you believe the franchise is so resilient and revered?

DC: Well, that goes back to Gene Roddenberry's genius and his vision. I think the enduring appeal of "Star Trek" is that it promises a future where our species has it together in terms of conquering poverty, racism, and developing a truly comfortable relationship with our own technology, which has yet to happen in today's world. I think what makes the appeal of "Star Trek" is that future.

I also think there are issues like the Prime Directive, which was Gene's response to the colonialism of the 19th century, where more advanced nations would just show up with their better technology, plant a flag, and feel they had the right to control them.

The Prime Directive stated that if the crew of a Federation starship encounters a more primitive species then we should not use our technology to change who they are and what their culture is. People want to believe we can evolve into a species where individuals are free to develop themselves to the best of their ability. That's always been the promise of our country, and has yet to be achieved. The dream of that halcyon future keeps audiences coming back.

Space.com: What was your gateway into sci-fi and which Hollywood movies struck a nerve?

DC: I've always been a science fiction fan, even as a little kid I had spacemen toys, toy spaceships and enjoyed making my own spaceships, which I ended up doing on "The Next Generation" a lot. Important films for me were "Earth vs. The Flying Saucers" and "The Seventh Voyage of Sinbad," where I could tell that there were different levels of reality within the image.  

After seeing "The Beast From 20,000 Fathoms" and reading how it was done, I made a crude rear-projection system by taping tracing paper inside a cardboard box and rear projecting images of my brother running around pretending to be chased by dinosaurs, and in the foreground, one frame at a time, stiffly moving toy dinosaurs. That was my first endeavor in visual effects. 

But the most significant film for me was "Forbidden Planet," which was the first big-budget, cerebral, science fiction epic that influenced every science fiction film of stature to come. Even as a boy watching it, I could tell there were paintings, there were models, cartoon animation, and they all blended together to create a new cinematic reality and that's what I wanted to do.

Another film, which led to me doing over one-hundred title sequences, was “Spartacus.” Saul Bass' brilliant work made me aware of the power of the title sequence. 

Space.com: In all the series you worked on, which Federation Starship was your favorite and why?

DC: That's difficult to determine. They all owe a debt to Matt Jefferies' innovative Enterprise-1701 for the original series. That combination of the classic flying saucer with other superstructures, and of course the parallel warp drive nacelles. 

The Enterprise-D, designed by Andy Probert under production designer Herman Zimmerman's supervision is elegant, and beautifully fluid. I always loved photographing that ship and just being in the presence of the beautiful models of the 1701-D. First, the one made by the team at ILM, then the four-footer made by Greg Jein. I always loved that ship. 

Then "Deep Space Nine" arrived, also designed under the supervision of Herman Zimmerman. That model was constructed by the great model maker Tony Meininger. I fell in love with that station the first time I saw the rough plywood mockup. 

"Voyager" came along, primarily designed by Rick Sternbach under production designer Richard James' supervision. That was a smaller, sleeker starship that had all the classic Federation elements like the twin nacelles and the main saucer shape, although in Voyager's case it was like an upside-down spoon.

Finally, the Enterprise NX-01 for "Star Trek: Enterprise," that ship was definitely one of my favorites. That was the first time we didn't have a physical model as it was an all-digital show. Kudos to Pierre Drolet who built the digital model. He put so much love into it with incredible detail so we could get really close to it on screen.

Choosing a favorite ship is like being asked which child you like best. You love them all and appreciate their differences.

Space.com: Do you own any prized mementos kept from the TV shows?

DC: Not much. It was frowned upon. Anything I wanted, I'd ask the producers for. I do have Bat'leth #1 and Mek'leth #1 and I have a little hand prop from "Deep Space Nine," a Cardassian device like an alien iPad that has my face on it as a deceased mad scientist. I have some of the shards left over when we'd blow up a model. Sometimes I'd make space debris made out of plastic parts melted over a candle. If we came upon a destroyed spaceship, the random plastic parts would be the debris that would fly by. I did keep a lot of my storyboards and concept sketches.

Space.com: What do you remember about your interactions with Gene Roddenberry?

DC: Well, we would talk a lot about visual effects but many of our personal discussions were philosophical … talking about what he felt were important themes for the show. One very fond memory was going to visit the mockup of the International Space Station. My son was quite young at the time and I brought him along. Gene at that time was in a wheelchair he'd ride around in. My son got tired so he toured the space station riding on Gene's lap chatting with him.

I also enjoy my friendship with Gene's son, Rod, who was an intern in the visual effects department while he was in high school. Rod has taken the legacy of his father's creation in a very honorable direction and does a lot of philanthropic work. He's someone who has earned my respect over the years by being a really great person.

Space.com: "Voyager" celebrates its 25th anniversary this year. How was that an important series in the development of the "Star Trek" franchise?

DC: It broke some ground by having a female captain. Kate Mulgrew took the job very seriously and took courses in science so she'd have a real grasp of what her character was all about. It was a very enjoyable cast to work with. I had a great opportunity to oversee the design of the title sequence as well. The producers were very busy, so I had the chance to pick out dream places I'd like to go if I was in space. Doing that title sequence was one of my happiest experiences. Jerry Goldsmith’s inspiring theme music gave the visuals majesty.

I really liked the premise of being in an uncharted part of our galaxy, the Delta Quadrant, so we could do all sorts of new things because we could encounter species that were new to the franchise. One of my favorite episodes was, "Basics Part 1 and 2," where our crew was marooned on a planet inhabited by primitive neolithic people. We got to create lava streams and volcanos, and a cave monster that ate our stunt coordinator Dennis Madalone. That was great fun

"Voyager" took on a lot of interesting themes. I liked the holographic doctor, brilliantly portrayed by Bob Picardo. It was a fresh look at the "Star Trek" universe, but from a different perspective.

Space.com: Can you tell us about your guitar-making hobby and that stunning "Star Trek" guitar?

DC: My colleague Ron Moore, who started as visual effects coordinator working with me, and then became visual effects supervisor, is also an excellent guitarist. He had the idea to do an art guitar. So we went down to Corona, California and had meetings with the Fender people. They sent me some guitar parts and we decided to go with the Stratocaster pattern.  

I got home and started laying out the guitar and drawing things on it.  George Amicay, Fender's master carver, carved the ships in high relief, primed the guitar, then sent it back to me. I did the final painting. Then Alan Hamel, head of the Fender Custom Shop, personally did all the electronics. It may be the only Fender Stratocaster without a separate pick guard because I wanted a seamless canvas to work on. It was in the Fender Museum for years.

Space.com: How did your time in the Peace Corps and travels though Asia influence some of the Klingon culture seen in the shows?

DC: After college I volunteered for the Peace Corp and was assigned to community development in northeast Thailand building small dams and bridges on tributaries of the Mekong River. I found out that each village had a generations-old, secret martial art they would practice. In ancient times they had no outside help to defend themselves from marauders. I began my interest in martial arts at that time, but also my interest in the architecture of Laos and Thailand and Nepal.

So when you see exteriors of Klingon cities or Klingon outposts, most of them were matte paintings by the great Syd Dutton. I'd work with him on evolving a style that was a composite of Thai, Lao, and Nepali architecture. I did some of the matte paintings myself, like the Klingon Lamasery, which is a Tibetan-looking building on a mountaintop inspired by a train trip I took through the Canadian Rockies.

When we had an episode where Worf was to inherit a bladed weapon, the art department sent down a weapon that looked like a pirate's cutlass. It was cool, but familiar. I felt we needed to do something better than that. I'd been imagining a weapon for years, but never had a reason to bring one into existence. I made one out of foam core and that became the Bat'leth.

Space.com: If given the keys to the kingdom for any "Star Trek" show, where would you take it?

DC: That's an interesting question. I would want to go with a new ship and a new crew like the people doing the current "Star Trek" shows. Make it optimistic but serious about exploration and stress the potential for humanity to reach a higher level of enlightenment.  

"Star Trek" realized its responsibility to not only inspire but educate their audience, and be a source of inspiration about relating ourselves to other species.

Space.com: How did being part of "Star Trek" affect your life as an artist, husband, and father?

DC: I had lots of opportunities to go off and do other features but I decided to stay with "Star Trek" because I felt part of the family. I was a member of the 18-year club of people that stayed with it from the beginning of "The Next Generation" to the end of "Enterprise."

My son grew up visiting the sets and knowing everybody. Until "Enterprise" ended, there was never a time when "Star Trek" wasn't a part of his life. One of the things I tried to stress with him growing up was that the principal characters always tried to make the right and honorable decision when confronting adversity. For me "Star Trek" was something I felt was a calling that became important to me to be a part of that legacy.

The illusions that created the universe of "Star Trek" were the result of many gifted and dedicated artists. There was no single hero of its visual effects. I was very fortunate to design and create a lot of things that became part of the "Star Trek" franchise. I feel it was a decent legacy to leave behind when I ultimately move into the non-biological phase of existence.

Titan Books' "Star Trek: The Artistry of Dan Curry" is available on Dec. 1.

Editor's note: All images from Star Trek: The Artistry of Dan Curry by Ben Robinson & Dan Curry provided by publisher by Titan Books. © 2020 CBS Studios Inc. © 2020 Paramount Pictures Corp. Star Trek and related marks and logos are trademarks of CBS Studios Inc. All Rights Reserved.

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Voyager 2's handlers beamed a set of test commands to the spacecraft on Thursday (Oct. 29) using the Deep Space Station 43 (DSS43) radio antenna in Canberra, Australia. Voyager 2 confirmed that it registered the instructions and executed them without incident, NASA officials said in an update on Monday (Nov. 2).

The commands were the first NASA had relayed to Voyager 2 since mid-March, when the 230-foot-wide (70 meters) DSS43 went offline for repairs and upgrades. This ongoing maintenance work is extensive, involving, among other things, the addition of two new radio transmitters, including one that is used to communicate with Voyager 2.

Voyager at 40: 40 photos from NASA's epic 'grand tour' mission

That particular transmitter hadn't been replaced in more than 47 years, NASA officials said.

"What makes this task unique is that we're doing work at all levels of the antenna, from the pedestal at ground level all the way up to the feedcones at the center of the dish that extend above the rim," Brad Arnold, of NASA's Jet Propulsion Lab in Southern California, said in Monday's update. 

"This test communication with Voyager 2 definitely tells us that things are on track with the work we're doing," said Arnold, the project manager for NASA's Deep Space Network (DSN).

That work, which will benefit communications with a wide range of NASA spacecraft, is scheduled to wrap up in February 2021, agency officials said.

The DSN is a network of radio dishes in three different, roughly equidistant locales — Canberra; Madrid, Spain; and Goldstone, California — that NASA uses to communicate with its farflung spacecraft. The Canberra site includes three smaller dishes that together can receive spacecraft relays, so the Voyager 2 team has been able to keep tabs on the distant probe even while the DSS43 work prevented them from sending commands.

And Voyager 2 cannot be hailed using DSN gear in Spain and California: The spacecraft is moving downward relative to Earth's orbital plane and can be reached only from the Southern Hemisphere.

Voyager 2 and its twin, Voyager 1, launched a few weeks apart in 1977 to conduct an epic "grand tour" of the solar system's giant planets. The two probes accomplished this unprecedented task; Voyager 1 flew by Jupiter and Saturn, and Voyager 2 had close encounters with Jupiter, Saturn, Uranus and Neptune. (The Neptune flyby, which included an up-close look at the planet's largest moon, Triton, is what sent Voyager heading "south," by the way.)

And then the Voyagers kept on flying. Voyager 1 entered interstellar space in August 2012, becoming the first human-made object ever to do so. Voyager 2 followed suit in late 2018.

Both spacecraft are still going strong, giving scientists their first up-close looks at the interstellar medium, the huge expanse of deep space beyond the sun's sphere of influence. The nuclear-powered Voyagers are running low on juice, however, so mission team members have turned off several instruments on the probes over the past few years to maximize their operational lives. Both spacecraft should have enough power to keep gathering data through 2024, mission team members have said.

Voyager 1 is currently about 14.1 billion miles (22.7 billion kilometers) from Earth, and Voyager 2 is 11.7 billion miles (18.8 billion km) from us. It therefore takes a command from mission control about 21 hours to get to Voyager 1 and nearly 17.5 hours to reach Voyager 2.

Mike Wall is the author of "Out There" (Grand Central Publishing, 2018; illustrated by Karl Tate), a book about the search for alien life. Follow him on Twitter @michaeldwall. Follow us on Twitter @Spacedotcom or Facebook. 

Alfred "Al" Worden, who died in March at the age of 88, is listed in the Guinness Book of World Records for being the "most isolated that any human has been from another person," a feat he achieved while orbiting high above the moon as part of NASA's Apollo 15 mission in 1971. Now his fans, friends and family are gathering virtually to celebrate his legacy.

"Colonel Al Worden departed this world for the second time on March 18, 2020. He left the first time on July 26, 1971, when he blasted off from Earth perched atop the giant Saturn V rocket that lifted him and his two crewmates on their epic journey to the moon and back," Worden's family posted online. "Throughout the five decades in-between — indeed throughout his entire active 88 years of life — Al Worden had a profound positive impact on thousands of people all over the world as he fulfilled his varied roles of explorer, engineer, educator, poet, friend, partner, father and benefactor."

Related: Apollo 15 in photos: a moon landing and the 1st moon buggy

"With COVID [the coronavirus pandemic] continuing to keep us physically distant, more than ever we need opportunities to come together for one worthy purpose. We'd love for you to join us in a celebration of the life of astronaut Al Worden."

The public is invited to watch the broadcast, which will begin at 11 a.m. EDT (1500 GMT) on Saturday (Sept. 19), by registering through the celebration's website.

Tributes will be delivered by those who knew Worden the best: his family, fellow astronauts and an array of people from around the world who worked with him to inspire the next generation of explorers.

"We have members of Al's family who will have a chance to tell some stories about Al — or 'Sonny' as they called him back on the farm in Michigan — and then members of Al's 1966 astronaut class, including Charlie Duke, Jack Lousma and Fred Haise," said Tom Kallman, president and CEO of Kallman Worldwide, who is organizing and hosting Saturday's celebration.

Other astronauts taking part include active NASA astronaut Drew Morgan, who like Worden graduated from the U.S. Military Academy at West Point, and British astronaut Tim Peake of the European Space Agency (ESA), who met Worden at the Paris Air Show during an appearance organized by Kallman Worldwide.

"We also have videos from the Middle East, Latin America and Asia, from people who will share how Al's life influenced them," said Kallman.

The program will briefly recount Worden's history as an Apollo 15 astronaut and his record-setting trip to the moon, as described by Francis French, the co-author of Worden's autobiography. In addition to being the most distant person in history, Worden was also the first astronaut to perform a spacewalk beyond Earth orbit.

Speakers will also highlight the aspects of Worden's personality that made him so memorable. Worden stood out due to his energy, optimism and humanity.

"If we can all remember to use Al as an example and live by that kind of example, the world could be a better place," Kallman said.

"We are also trying to make this celebration be a feel good event. We will have some fun with our Hawaiian shirts," he said, referring to Worden's trademark look. "I think the average person tuning in who only knows that Worden was an Apollo astronaut will get a sense for the impact that he had."

The celebration had originally been planned as a hybrid in-person and online event to coincide with the anniversary of Worden's moon mission in July. The continuing impact of the pandemic necessitated that the tribute be virtual. Once the program streams on Saturday, the video will be available on demand.

In addition to the celebration, Kallman Worldwide is also accepting donations for the Astronaut Al Worden Endeavour Scholarship Foundation, which underwrites sending students and educators from around the world to attend Space Camp in Huntsville, Alabama.

Follow collectSPACE.com on Facebook and on Twitter at @collectSPACE. Copyright 2020 collectSPACE.com. All rights reserved.

That's according to scientists who analyzed archived Voyager 2 observations of the magnetic field around Uranus. These measurements had been studied before, but only using a relatively coarse view. In the new research, scientists instead looked at those measurements every two seconds. That detail showed what had previously been missed: an abrupt zigzag in the magnetic field readings that lasted just one minute of the spacecraft's 45-hour journey past Uranus.

The tiny wobble in the Voyager 2 data represents something much larger since the spacecraft was flying so fast. Specifically, the scientists behind the new research believe the zigzag marks a plasmoid, a type of structure that wasn't understood particularly well at the time of the flyby in January 1986.

Related: Photos of Uranus, the tilted giant planet

But by now, plasmoids have earned scientists' respect. A plasmoid is a massive bubble of plasma, which is a soup of charged particles. Plasmoids can break off from the tip of the sleeve of magnetism surrounding a planet like a teardrop. 

Scientists have studied these structures at Earth and nearby planets, but never at Uranus or its neighbor Neptune, since Voyager 2 is the only spacecraft to date ever to visit those planets.

Scientists want to know about plasmoids because these structures can pull charged particles out of a planet's atmosphere and fling them into space. And if you change a planet's atmosphere, you change the planet itself. And Uranus' situation is particularly complicated because the planet rotates on its side and its magnetic field is skewed from both that axis and the plane all the planets lie in.

Because Voyager 2 flew straight through this plasmoid, scientists could use the archived data to measure the structure, which they believe was about 250,000 miles (400,000 kilometers) across and could have stretched 127,000 miles (204,000 km) long, according to a NASA statement.

Ideally, scientists would piece together more observations of Uranus' magnetic field, enough to better understand how this phenomenon has shaped the planet over time. But that will require another spacecraft visit the strange sideways world.

The research is described in a paper published in August in the journal Geophysical Review Letters. NASA announced the finding on Wednesday (March 25).

•  Uranus may have odd, strobe-like magnetic field 
•  Why is Uranus on its side? Incredible simulations could solve the mystery. 
•  How did Uranus form? 

Email Meghan Bartels at mbartels@space.com or follow her @meghanbartels. Follow us on Twitter @Spacedotcom and on Facebook. 

NASA is upgrading the 230-foot-wide (70 meters) radio dish in Australia that mission team members use to send commands to Voyager 2, which launched in 1977 and entered interstellar space in November 2018. Voyager 2 will be on its own until that work is done in January 2021, though the spacecraft will still be able to beam science data home.

But don't worry too much about Voyager 2; it should be able to handle its extended isolation, mission team members said.

Related: Voyager at 40: 40 photos from NASA's epic 'grand tour' mission

"We put the spacecraft back into a state where it will be just fine, assuming that everything goes normally with it during the time that the antenna is down," Voyager project manager Suzanne Dodd, who also serves as director of the Interplanetary Network Directorate at NASA's Jet Propulsion Laboratory in Pasadena, California, said in a statement Wednesday (March 4).

"If things don't go normally — which is always a possibility, especially with an aging spacecraft — then the onboard fault protection that's there can handle the situation," Dodd added.

The Australian radio dish is part of the Deep Space Network (DSN), the system NASA uses to communicate with its many space probes. There are three DSN sites — one each in California, Spain and Australia.

Each site has multiple big antennas. For example, the Australian complex, which lies about 25 miles (40 kilometers) southwest of Canberra, also features three 111-foot-wide (34 m) radio dishes. The 111-footers can receive science data, but only the 230-foot one has the special transmitter required to beam commands to Voyager 2, NASA officials said.

The California and Spain DSN sites are no help in this regard, either. Voyager 2, which is currently more than 11 billion miles (17 billion kilometers) from Earth, is moving downward relative to our planet's orbital plane and, therefore, can be hailed only from the Southern Hemisphere.

The big Australian dish has been operating for 48 years and needs the upgrade, NASA officials said. The agency decided to start the work now — the upgrade is scheduled to begin "in early March," according to the Wednesday NASA statement — because Voyager 2 recently bounced back from a glitch and is healthy again, the officials added.

"Obviously, the 11 months of repairs puts more constraints on the other DSN sites," Jeff Berner, the Deep Space Network's chief engineer, said in the same statement. "But the advantage is that when we come back, the Canberra antenna will be much more reliable."

The upgrade will improve communications with many NASA spacecraft, not just Voyager 2, agency officials said. For example, the work will benefit NASA's Mars 2020 rover, which is scheduled to launch this summer, and the agency's Artemis program of crewed lunar exploration, which aims to land two astronauts near the moon's south pole in 2024.

"The maintenance is needed to support the missions that NASA is developing and launching in the future, as well as supporting the missions that are operating right now," Dodd said.

Voyager 2 and its twin, Voyager 1, launched a few weeks apart in 1977 to perform an unprecedented "grand tour" of the solar system's giant planets — Jupiter, Saturn, Uranus and Neptune. The duo aced this task and then kept on flying, all the way out to interstellar space.

Voyager 1 reached this exploration frontier in August 2012, becoming the first human-made object ever to leave the heliosphere, the big bubble of magnetic fields and charged particles that the sun blows around itself. Voyager 2 followed about six years later.

The two craft are running low on power, and mission team members have turned off a few science instruments to maximize the remaining juice and extend the probes' lifetimes. Both spacecraft probably have enough power left to keep gathering data through 2024, mission team members have said.

• Photos from NASA's Voyager 1 and 2 probes 
• Voyager 2's trip to interstellar space deepens some mysteries beyond our solar system
• Voyager 1's historic flyby of Jupiter in photos

Mike Wall is the author of "Out There" (Grand Central Publishing, 2018; illustrated by Karl Tate), a book about the search for alien life. Follow him on Twitter @michaeldwall. Follow us on Twitter @Spacedotcom or Facebook. 

NASA made the announcement yesterday (March 3), over a month after the incident occurred. Troubleshooting for the spacecraft is a slow process because of its distance from Earth; it takes 17 hours for each command to reach the probe and for data indicating its efficacy to reach engineers.

"Voyager 2 has returned to normal operations following the anomaly on Jan. 25, 2020," NASA officials wrote in a statement. "The five operating science instruments, which were turned off by the spacecraft's fault protection routine, are back on and returning normal science data."

Related: Voyager at 40: 40 photos from NASA's epic 'grand tour' mission

Voyager 2, like its twin Voyager 1, launched in August 1977 and has been exploring ever since. Such extensive space travel takes its toll; as the spacecraft have long exceeded their mission expectancy, engineers have needed to improvise ways to keep the probes going, particularly as their power supplies dwindle.

The January problem occurred when Voyager 2 missed a spin maneuver to calibrate its magnetic-field instrument. That glitch left two power-hungry systems on simultaneously; the spacecraft recognized the risk of the situation and triggered a preprogrammed fault-protection mode.

Since then, mission engineers have been working to turn off the power-sucking systems and to get Voyager 2's five remaining science instruments back to work. Those instruments are helping scientists understand what happens beyond the heliosphere, the bubble of space influenced by our sun. Voyager 2 left that bubble in November 2018, entering interstellar space.

•  Photos from NASA's Voyager 1 and 2 probes 
•  Voyager 1's historic flyby of Jupiter in photos 
•  Voyager 1 spacecraft's road to interstellar space: a photo timeline 

Email Meghan Bartels at mbartels@space.com or follow her @meghanbartels. Follow us on Twitter @Spacedotcom and on Facebook.