where is voyager 1 in the milky way

Scientists' predictions for the long-term future of the Voyager Golden Records will blow your mind

Buckle up, everyone, and let's take a ride on a universe-size time machine.

The future is a slippery thing, but sometimes physics can help. And while human destiny will remain ever unknown, the fate of two of our artifacts can be calculated in staggering detail.

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.

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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 [email protected] 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

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Within 148 pages, explore the mysteries of Mars. With the latest generation of rovers, landers and orbiters heading to the Red Planet, we're discovering even more of this world's secrets than ever before. Find out about its landscape and formation, discover the truth about water on Mars and the search for life, and explore the possibility that the fourth rock from the sun may one day be our next home.

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. 

Join our Space Forums to keep talking space on the latest missions, night sky and more! And if you have a news tip, correction or comment, let us know at: [email protected].

Meghan is a senior writer at Space.com and has more than five years' experience as a science journalist based in New York City. She joined Space.com in July 2018, with previous writing published in outlets including Newsweek and Audubon. Meghan earned an MA in science journalism from New York University and a BA in classics from Georgetown University, and in her free time she enjoys reading and visiting museums. Follow her on Twitter at @meghanbartels.

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The most distant human-made object

No spacecraft has gone farther than NASA's Voyager 1. Launched in 1977 to fly by Jupiter and Saturn, Voyager 1 crossed into interstellar space in August 2012 and continues to collect data.

Mission Type

What is Voyager 1?

Voyager 1 has been exploring our solar system for more than 45 years. The probe is now in interstellar space, the region outside the heliopause, or the bubble of energetic particles and magnetic fields from the Sun.

• Voyager 1 was the first spacecraft to cross the heliosphere, the boundary where the influences outside our solar system are stronger than those from our Sun.
• Voyager 1 is the first human-made object to venture into interstellar space.
• Voyager 1 discovered a thin ring around Jupiter and two new Jovian moons: Thebe and Metis.
• At Saturn, Voyager 1 found five new moons and a new ring called the G-ring.

In Depth: Voyager 1

Voyager 1 was launched after Voyager 2, but because of a faster route, it exited the asteroid belt earlier than its twin, having overtaken Voyager 2 on Dec. 15, 1977.

Voyager 1 at Jupiter

Voyager 1 began its Jovian imaging mission in April 1978 at a range of 165 million miles (265 million km) from the planet. Images sent back by January the following year indicated that Jupiter’s atmosphere was more turbulent than during the Pioneer flybys in 1973–1974.

Beginning on January 30, Voyager 1 took a picture every 96 seconds for a span of 100 hours to generate a color timelapse movie to depict 10 rotations of Jupiter. On Feb. 10, 1979, the spacecraft crossed into the Jovian moon system and by early March, it had already discovered a thin (less than 30 kilometers thick) ring circling Jupiter.

Voyager 1’s closest encounter with Jupiter was at 12:05 UT on March 5, 1979 at a range of about 174,000 miles (280,000 km). It encountered several of Jupiter’s Moons, including Amalthea, Io, Europa, Ganymede, and Callisto, returning spectacular photos of their terrain, opening up completely new worlds for planetary scientists.

The most interesting find was on Io, where images showed a bizarre yellow, orange, and brown world with at least eight active volcanoes spewing material into space, making it one of the most (if not the most) geologically active planetary body in the solar system. The presence of active volcanoes suggested that the sulfur and oxygen in Jovian space may be a result of the volcanic plumes from Io which are rich in sulfur dioxide. The spacecraft also discovered two new moons, Thebe and Metis.

Voyager 1 at Saturn

Following the Jupiter encounter, Voyager 1 completed an initial course correction on April 9, 1979 in preparation for its meeting with Saturn. A second correction on Oct. 10, 1979 ensured that the spacecraft would not hit Saturn’s moon Titan.

Its flyby of the Saturn system in November 1979 was as spectacular as its previous encounter. Voyager 1 found five new moons, a ring system consisting of thousands of bands, wedge-shaped transient clouds of tiny particles in the B ring that scientists called “spokes,” a new ring (the “G-ring”), and “shepherding” satellites on either side of the F-ring—satellites that keep the rings well-defined.

During its flyby, the spacecraft photographed Saturn’s moons Titan, Mimas, Enceladus, Tethys, Dione, and Rhea. Based on incoming data, all the moons appeared to be composed largely of water ice. Perhaps the most interesting target was Titan, which Voyager 1 passed at 05:41 UT on November 12 at a range of 2,500 miles (4,000 km). Images showed a thick atmosphere that completely hid the surface. The spacecraft found that the moon’s atmosphere was composed of 90% nitrogen. Pressure ad temperature at the surface was 1.6 atmospheres and 356 °F (–180°C), respectively.

Atmospheric data suggested that Titan might be the first body in the solar system (apart from Earth) where liquid might exist on the surface. In addition, the presence of nitrogen, methane, and more complex hydrocarbons indicated that prebiotic chemical reactions might be possible on Titan.

Voyager 1’s closest approach to Saturn was at 23:46 UT on 12 Nov. 12, 1980 at a range of 78,000 miles(126,000 km).

Voyager 1’s ‘Family Portrait’ Image

Following the encounter with Saturn, Voyager 1 headed on a trajectory escaping the solar system at a speed of about 3.5 AU per year, 35° out of the ecliptic plane to the north, in the general direction of the Sun’s motion relative to nearby stars. Because of the specific requirements for the Titan flyby, the spacecraft was not directed to Uranus and Neptune.

The final images taken by the Voyagers comprised a mosaic of 64 images taken by Voyager 1 on Feb. 14, 1990 at a distance of 40 AU of the Sun and all the planets of the solar system (although Mercury and Mars did not appear, the former because it was too close to the Sun and the latter because Mars was on the same side of the Sun as Voyager 1 so only its dark side faced the cameras).

This was the so-called “pale blue dot” image made famous by Cornell University professor and Voyager science team member Carl Sagan (1934-1996). These were the last of a total of 67,000 images taken by the two spacecraft.

Voyager 1’s Interstellar Mission

All the planetary encounters finally over in 1989, the missions of Voyager 1 and 2 were declared part of the Voyager Interstellar Mission (VIM), which officially began on Jan. 1, 1990.

The goal was to extend NASA’s exploration of the solar system beyond the neighborhood of the outer planets to the outer limits of the Sun’s sphere of influence, and “possibly beyond.” Specific goals include collecting data on the transition between the heliosphere, the region of space dominated by the Sun’s magnetic field and solar field, and the interstellar medium.

On Feb. 17, 1998, Voyager 1 became the most distant human-made object in existence when, at a distance of 69.4 AU from the Sun when it “overtook” Pioneer 10.

On Dec. 16, 2004, Voyager scientists announced that Voyager 1 had reported high values for the intensity for the magnetic field at a distance of 94 AU, indicating that it had reached the termination shock and had now entered the heliosheath.

The spacecraft finally exited the heliosphere and began measuring the interstellar environment on Aug. 25, 2012, the first spacecraft to do so.

On Sept. 5, 2017, NASA marked the 40th anniversary of its launch, as it continues to communicate with NASA’s Deep Space Network and send data back from four still-functioning instruments—the cosmic ray telescope, the low-energy charged particles experiment, the magnetometer, and the plasma waves experiment.

The Golden Record

Each of the Voyagers contain a “message,” prepared by a team headed by Carl Sagan, in the form of a 12-inch (30 cm) diameter gold-plated copper disc for potential extraterrestrials who might find the spacecraft. Like the plaques on Pioneers 10 and 11, the record has inscribed symbols to show the location of Earth relative to several pulsars.

The records also contain instructions to play them using a cartridge and a needle, much like a vinyl record player. The audio on the disc includes greetings in 55 languages, 35 sounds from life on Earth (such as whale songs, laughter, etc.), 90 minutes of generally Western music including everything from Mozart and Bach to Chuck Berry and Blind Willie Johnson. It also includes 115 images of life on Earth and recorded greetings from then U.S. President Jimmy Carter (1924– ) and then-UN Secretary-General Kurt Waldheim (1918–2007).

By January 2024, Voyager 1 was about 136 AU (15 billion miles, or 20 billion kilometers) from Earth, the farthest object created by humans, and moving at a velocity of about 38,000 mph (17.0 kilometers/second) relative to the Sun.

National Space Science Data Center: Voyager 1

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Voyager: What’s next for NASA’s interstellar probes?

In 1977, NASA launched the twin Voyager spacecraft to probe the outer reaches of our solar system. The space agency was still in its infancy then. But with the triumph of the Apollo Moon landings just five years behind them, NASA was ready to dive headfirst into another bold idea.

Thanks to a rare alignment of the solar system’s four outer planets — which happens just once every 175 years — the agency had the chance to redefine astronomy by exploring Jupiter, Saturn, Uranus and Neptune in one fell swoop.

The scheme was a stunning success.

At Jupiter, the probes surprised scientists when they spotted volcanoes on the moon Io and discovered Europa is likely an ocean world . Saturn surrendered its atmospheric composition and new rings. And Voyager 2 returned humanity’s only close-up looks at Uranus and Neptune . To this day, scientists are still making new discoveries by exploring Voyager’s decades-old data.

Where are the Voyager Probes Going?

Even traveling at 35,000 mph, the Voyager probes will need another 300 years just to reach the inner edge of the Oort Cloud — a large sphere of icy space rocks that begins a couple of thousand times farther from the Sun than Earth. The outer edge of the Oort Cloud may be so distant that it take the Voyager probes 30,000 years or more to completely cross it, according to NASA .

After that, in about 40,000 years, Voyager 1 could finally approach another star. Voyager 2, however, will need 300,000 years before it comes close to bathing in the light of another star.

Thankfully, we don’t have to wait that long for new discoveries. Both probes are still making fascinating finds along the way.

What is the Voyager Mission Studying?

Back in 2012, Voyager 1 became the first spacecraft to reach interstellar space. There are no road signs letting NASA know that the craft broke the barrier. Instead, they determined it thanks to measurable changes Voyager 1 detected when it hit a region called the heliopause.

Our Sun produces an intense stream of particles, dubbed the solar wind, that flows outward in all directions and creates a magnetic field that shields the planets from interstellar particles. The powerful wind carves a huge cavity in the interstellar medium (the region between stars) that encapsulates all the planets. This protective bubble is called the heliosphere, and the heliopause is its outer boundary — where our Sun’s influence is finally overpowered by distant activity like erupting supernovas.

Scientists were surprised when Voyager 1 measured the magnetic field just inside and just outside of the heliopause, finding no significant changes in its overall direction. Then, when Voyager 2 reached this same boundary of interstellar space in 2018, it found similar results.

But Voyager 2 offered up another surprise when NASA scientists released its first results from beyond the heliopause. They had originally expected that particles from our sun would not “leak out” of the heliosphere into interstellar space. And Voyager 1 saw no such leakage. But Voyager 2 found the opposite. It recorded a small trickle of solar particles streaming through the heliopause.

In recent years, the twin probes also have discovered that the solar wind moves more slowly at our solar system’s edge than expected. All said, by studying data from the two probes, astronomers have been able to compare, contrast and confirm results about the boundary that separates our solar system from interstellar space.

When Will Voyager 1 and Voyager 2 Die?

Since their launch more than 40 years ago, NASA has remained in near-constant contact with the Voyager probes. However, the space agency has temporarily stopped receiving messages from Voyager 2 while they work to repair and update one of the three Deep Space Network antennas used to communicate with the probes, The New York Times reported in March.

It’s a risky move, and there’s a chance we may not hear from Voyager 2 once the receivers are turned back on. But Earth is still in contact with Voyager 1. And the discoveries haven’t ended quite yet. Mission planners intend to keep communicating with the spacecraft until they fail or lose power.

Both should be able to keep at least one scientific instrument running until 2025. And even after that, NASA expects to continue receiving engineering data from the probes until 2035, when they exceed the range of the Deep Space Network antennas.

Sadly, that means the so-called interstellar mission won’t be able to tell us what they see once they reach the stars.

A Golden Record of the Journey

Of course, NASA knew this day would come long before the missions launched. And this lonesome, one-way ticket out of the solar system was more than some astronomers could resist. Carl Sagan was so drawn to the idea that he helped NASA create an entire cultural component for the mission, lest some future aliens — or spacefaring earthlings — found one of the Voyager probes.

Each spacecraft carries a golden record that serves as a time capsule from Earth, with their contents chosen by a committee led by Sagan. These messages to the stars contain sights and sounds from Earth, as well as music from dozens of countries and greetings spoken in 55 languages from around the world.

So, while someday we’ll stop hearing back from the Voyager probes, it might not be the last message conveyed on their journey to the stars.

“Billions of years from now, our Sun, then a distended red giant star, will have reduced Earth to a charred cinder,” Sagan opined. “But the Voyager record will still be largely intact, in some other remote region of the Milky Way galaxy, preserving a murmur of an ancient civilization that once flourished — perhaps before moving on to greater deeds and other worlds — on the distant planet Earth.”

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Voyager 1 Leaves Solar System, NASA Confirms

NASA’s far-flung spacecraft passed into interstellar space last year.

It’s official: Voyager 1 has slipped from the solar system.

Launched in 1977 , Voyager 1 traveled past Jupiter and Saturn and is now more than 11.66 billion miles (18.67 billion kilometers) from the sun, becoming the first spacecraft to enter interstellar space. Proof of this long-anticipated milestone for the storied spacecraft comes in a study released Thursday by the journal Science and announced at a celebratory NASA headquarters briefing.

"We made it! We are in interstellar space," said Voyager scientist Ed Stone of the California Institute of Technology in Pasadena, speaking at the briefing.

Solar storm aftershocks at the edge of the solar system provide confirmation that the Voyager 1 spacecraft made the passage on August 25, 2012, space agency scientists said Thursday.

On that date, Voyager 1 passed beyond the fringes of the sun's outward-flowing solar wind and into the interstellar space between the stars.

"It is an incredible event, to send the first human object into interstellar space," says study lead author Donald Gurnett of the University of Iowa in Iowa City. "It’s not quite the moon landing, but we are where the solar wind ends."

Finding the Solar System’s Edge

The solar wind flows outward from the sun traveling at one million miles (1.6 million kilometers) an hour, a bath of energetic particles that's blasted off the solar surface and into space, where it surrounds our star like a bubble.

At its edges, the solar wind piles up into the "interstellar wind," a cloud of cooler charged particles that suffuse the thin vacuum of space between stars. Since 2004, Voyager 1 had been traveling within the boundary region between the solar wind and the interstellar wind, which is the cooked-off debris of thousands of exploded stars in our Milky Way galaxy.

Knowing exactly where the solar wind ends and where interstellar space begins has been an open question among space scientists for more than four decades, says Stone.

Since an instrument for directly detecting that transition died in 1980, the researchers have had to rely on indirect measures of magnetic and electrical activity from other instruments aboard Voyager 1 to find an answer.

One key to identifying this boundary is the difference in the density of charged particles between the solar wind and interstellar space, as it is about 50 times greater in the latter region.

Looking at a pair of solar storms that caught up to the spacecraft last October and then again last April, Gurnett’s team reported that measured changes in electrical activity around Voyager correspond to interstellar space.

As the storms passed the spacecraft, they triggered spikes in electrical and radio waves that uniquely corresponded in frequency to the spacecraft having entered the more densely charged interstellar space.

Based on that increase, the team extrapolated the entry date for Voyager 1 into interstellar space as August 25, 2012.

"The spacecraft doesn't feel anything traveling into interstellar space. We can only detect the transition because of its instruments," says Stone, who was not on the study team.

The new report confirms an analysis made last year that found that Voyager had entered interstellar space, based on indirect measurements.

Stone finds the new report convincing: "Nature has finally given us a nice set of solar storms which show us that Voyager is now out in interstellar space."

Surprise! Galaxy, Sun's Magnetic Fields Aligned

Scientists were surprised by NASA's finding that the galaxy's magnetic field is apparently aligned in the same direction as the sun's, forming a "magnetic highway." Space scientists had generally assumed that the galaxy's magnetic field would have some other direction.

The alignment had stymied attempts to use magnetic measurements to determine a starting line for interstellar space.

"We have a lot to learn still, I think, is what it means," says Voyager scientist Stamatios Krimigis of the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, who reported the magnetic highway results last year .

Along with Voyager 1's measurement of increased galactic cosmic rays (the solar wind serves to partly shield the solar system from these high-powered rays), the new results have Krimigis "absolutely convinced."

"In the same way that Sputnik carried us out of the Earth's atmosphere in 1957, Voyager has now carried us outside the sun's atmosphere," Krimigis says. "It is quite an achievement in the short time that we have had spaceflight."

Given the estimated lifetime of the plutonium battery aboard Voyager 1, its last signals should be heard on Earth around 2025, Stone says. The spacecraft will eventually pass within 1.7 light years (about 16.1 trillion kilometers) of another star in 40,000 years, according to Voyager project manager Suzanne Dodd of NASA's Jet Propulsion Laboratory in Pasadena, California.

The spacecraft's twin, Voyager 2, which explored Jupiter, Saturn, Uranus, and Neptune, is also still kicking, now some 9.55 billion miles (15.36 billion kilometers) from the sun on its own journey.

"It has really been an exciting 40 years for the mission, and the next 10 years should be exciting ones as well," Stone says. "We are still exploring places we have never been."

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Voyager space probes show outsiders' view of Milky Way

By Lisa Grossman

1 December 2011

No longer blinded by the light

(Image: JPL Archives/NASA)

This map of the infrared Milky Way includes the light of half a billion stars

(Image: Infrared Processing and Analysis Center/Caltech & University of Massachusetts)

The twin Voyager probes are so far from the sun that they can see a kind of light from the Milky Way that we on Earth cannot. The observations could act as a Rosetta stone for understanding star formation in more distant and ancient galaxies.

The veteran Voyagers, which were launched in 1977 and are slowly approaching the outer limit of the solar system , have detected a particular wavelength of light called Lyman-alpha emission coming from our home galaxy for the first time.

The light is useful because it is a trace of star formation in other galaxies. Hot young stars blast their surroundings with high-energy photons, stripping electrons from hydrogen atoms. Those stripped atoms eventually find another electron and absorb it to become whole again. When they do, they can emit two kinds of photons: H-alpha and Lyman-alpha.

A tale of two photons

H-alpha photons, which are in the visible part of the electromagnetic spectrum, tend to sail through interstellar gas unimpeded. But Lyman-alpha photons, which are in the shorter-wavelength ultraviolet range, tend to be absorbed by this gas and later re-emitted.

The complicated histories and trajectories of Lyman-alpha photons make H-alpha photons more straightforward telltales of star formation – for stars that are closer than about 8 billion light years. If H-alpha photons make a longer journey than that, the expansion of the universe stretches them too much for our telescopes to detect. This means we cannot learn about star formation in the early universe by studying H-alpha photons reaching us now.

Lyman-alpha light has a shorter wavelength to begin with, and even stretching it out over vast distances leaves it in the easily detectable visible region of the spectrum. “The only way to observe primordial galaxies and check the first stars that formed in the early universe is to look at Lyman-alpha,” says Rosine Lallement of the Paris Observatory in France.

Solar glare

But even though we can see this visible-light Lyman-alpha coming from galaxies across the universe, we are blind to the unstretched version in our own. That’s because the sun pumps out vast quantities of ultraviolet Lyman-alpha light, and this is then scattered by gas within the solar system. The light from any other Lyman-alpha sources in the Milky Way is still ultraviolet when it reaches us, so gets lost in the glare of the sun’s output, like candle flames next to a searchlight.

Now Lallement and her colleagues have confirmed that the Voyager spacecraft have seen past this haze into star-forming regions in the wider galaxy. “You still see this glow [from the sun], and it is the dominant radiation you measure,” she says. “But you begin to see, superimposed, the small galactic sources which are much farther away, which are coming from the spiral arms and the star-forming regions in the Milky Way disc.”

The emission showed up when astronomers began scanning the sky using ultraviolet spectrographs on the probes in 1993, when Voyager 1 was about 40 astronomical units away from the sun (1 AU is the distance from the Earth to the sun).

Lallement and colleagues analysed 10 years of scans taken by Voyager 1 and five years of scans from Voyager 2. They found that spikes in Lyman-alpha emissions matched previously observed H-alpha emissions from star-forming regions in the Milky Way.

Because only Lyman-alpha emission is visible in very distant galaxies, and only H-alpha emission had previously been detected in the Milky Way, seeing them both in our galaxy will allow astronomers to better interpret star formation in other galaxies, Lallement says.

“In the Milky Way, you know exactly where the new stars are, the motion, the kinematics, you have everything you need to exactly test your propagation models,” she says. “Because we know everything in detail, it is now possible to have a test case for those models.”

Jeffrey Linsky of the University of Colorado at Boulder says the find is a bonus. “The primary mission of the Voyagers was to study the outer planets and their environments,” he writes in a commentary about the study. “Who would have anticipated the new accomplishments of these spacecraft more than 20 years later?”

No more scans

To conserve power, the Voyager systems that scanned the skies for Lyman-alpha signals have been turned off for years. “It is ironic that the electrical power on the Voyagers is decreasing with time as the Lyman-alpha foreground keeps improving,” says Linsky.

But Lallement says she doesn’t mind. At 119 and 97 AU from the sun, Voyagers 1 and 2 are near the edge of the region of space dominated by the sun and its magnetic field. Turning off the ultraviolet spectrographs will allow the spacecraft to keep sending data back to Earth until at least 2020.

“For the first time, we will really get information as if we were travelling in interstellar space,” Lallement says. “I don’t complain about that.”

Journal references: Science , DOI: 10.1126/science.1197340 and DOI: 10.1126/science.1200166

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Some hope —

Finally, engineers have a clue that could help them save voyager 1, a new signal from humanity's most distant spacecraft could be the key to restoring it..

Stephen Clark - Mar 15, 2024 11:23 pm UTC

It's been four months since NASA's Voyager 1 spacecraft sent an intelligible signal back to Earth, and the problem has puzzled engineers tasked with supervising the probe exploring interstellar space.

But there's a renewed optimism among the Voyager ground team based at NASA's Jet Propulsion Laboratory in California. On March 1, engineers sent a command up to Voyager 1—more than 15 billion miles (24 billion kilometers) away from Earth—to "gently prompt" one of the spacecraft's computers to try different sequences in its software package. This was the latest step in NASA's long-distance troubleshooting to try to isolate the cause of the problem preventing Voyager 1 from transmitting coherent telemetry data.

Cracking the case

Officials suspect a piece of corrupted memory inside the Flight Data Subsystem (FDS), one of three main computers on the spacecraft, is the most likely culprit for the interruption in normal communication. Because Voyager 1 is so far away, it takes about 45 hours for engineers on the ground to know how the spacecraft reacted to their commands—the one-way light travel time is about 22.5 hours.

The FDS collects science and engineering data from the spacecraft's sensors, then combines the information into a single data package, which goes through a separate component called the Telemetry Modulation Unit to beam it back to Earth through Voyager's high-gain antenna.

Engineers are almost entirely certain the problem is in the FDS computer. The communications systems onboard Voyager 1 appear to be functioning normally, and the spacecraft is sending a steady radio tone back to Earth, but there's no usable data contained in the signal. This means engineers know Voyager 1 is alive, but they have no insight into what part of the FDS memory is causing the problem.

But Voyager 1 responded to the March 1 troubleshooting command with something different from what engineers have seen since this issue first appeared on November 14.

"The new signal was still not in the format used by Voyager 1 when the FDS is working properly, so the team wasn’t initially sure what to make of it," NASA said in an update Wednesday. "But an engineer with the agency’s Deep Space Network, which operates the radio antennas that communicate with both Voyagers and other spacecraft traveling to the Moon and beyond, was able to decode the new signal and found that it contains a readout of the entire FDS memory."

Now, engineers are meticulously comparing each bit of code from the FDS memory readout to the memory readout Voyager 1 sent back to Earth before the issue arose in November. This, they hope, will allow them to find the root of the problem. But it will probably take weeks or months for the Voyager team to take the next step. They don't want to cause more harm.

"Using that information to devise a potential solution and attempt to put it into action will take time," NASA said.

This is perhaps the most serious ailment the spacecraft has encountered since its launch in 1977. Voyager 1 flew by Jupiter and Saturn before getting a kick from Saturn's gravity to speed into the outer solar system. In 2012, Voyager 1 entered interstellar space when it crossed the heliopause, where the solar wind, the stream of particles emanating from the Sun, push against a so-called galactic wind, the particles that populate the void between the stars.

Engineers have kept Voyager 1 and its twin, Voyager 2, alive for more than 46 years , overcoming technical problems that have doomed other space missions. Both probes face waning power from their nuclear batteries, and there are concerns about their thrusters aging and fuel lines becoming clogged, among other things. But each time there is a problem, ground teams have come up with a trick to keep the Voyagers going, often referencing binders of fraying blueprints and engineering documents from the spacecraft's design and construction nearly 50 years ago.

Suzanne Dodd, NASA's project manager for Voyager 1 and its twin, Voyager 2, recently told Ars that engineers would need to pull off their "biggest miracle" to restore Voyager 1 to normal operations. Now, Voyager 1's voice from the sky has provided engineers with a clue that could help them realize this miracle.

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Channel ars technica.

NASA’s Voyager 1 Resumes Sending Engineering Updates to Earth

NASA’s Voyager 1 spacecraft is depicted in this artist’s concept traveling through interstellar space, or the space between stars, which it entered in 2012.

After some inventive sleuthing, the mission team can — for the first time in five months — check the health and status of the most distant human-made object in existence.

For the first time since November , NASA’s Voyager 1 spacecraft is returning usable data about the health and status of its onboard engineering systems. The next step is to enable the spacecraft to begin returning science data again. The probe and its twin, Voyager 2, are the only spacecraft to ever fly in interstellar space (the space between stars).

Voyager 1 stopped sending readable science and engineering data back to Earth on Nov. 14, 2023, even though mission controllers could tell the spacecraft was still receiving their commands and otherwise operating normally. In March, the Voyager engineering team at NASA’s Jet Propulsion Laboratory in Southern California confirmed that the issue was tied to one of the spacecraft’s three onboard computers, called the flight data subsystem (FDS). The FDS is responsible for packaging the science and engineering data before it’s sent to Earth.

After receiving data about the health and status of Voyager 1 for the first time in five months, members of the Voyager flight team celebrate in a conference room at NASA’s Jet Propulsion Laboratory on April 20.

The team discovered that a single chip responsible for storing a portion of the FDS memory — including some of the FDS computer’s software code — isn’t working. The loss of that code rendered the science and engineering data unusable. Unable to repair the chip, the team decided to place the affected code elsewhere in the FDS memory. But no single location is large enough to hold the section of code in its entirety.

So they devised a plan to divide the affected code into sections and store those sections in different places in the FDS. To make this plan work, they also needed to adjust those code sections to ensure, for example, that they all still function as a whole. Any references to the location of that code in other parts of the FDS memory needed to be updated as well.

The team started by singling out the code responsible for packaging the spacecraft’s engineering data. They sent it to its new location in the FDS memory on April 18. A radio signal takes about 22 ½ hours to reach Voyager 1, which is over 15 billion miles (24 billion kilometers) from Earth, and another 22 ½ hours for a signal to come back to Earth. When the mission flight team heard back from the spacecraft on April 20, they saw that the modification worked: For the first time in five months, they have been able to check the health and status of the spacecraft.

Get the Latest News from the Final Frontier

During the coming weeks, the team will relocate and adjust the other affected portions of the FDS software. These include the portions that will start returning science data.

Voyager 2 continues to operate normally. Launched over 46 years ago , the twin Voyager spacecraft are the longest-running and most distant spacecraft in history. Before the start of their interstellar exploration, both probes flew by Saturn and Jupiter, and Voyager 2 flew by Uranus and Neptune.

Caltech in Pasadena, California, manages JPL for NASA.

News Media Contact

Calla Cofield

Jet Propulsion Laboratory, Pasadena, Calif.

626-808-2469

[email protected]

Lego reveals two NASA approved space sets for Artemis rocket and Milk Way galaxy

T wo new Lego space sets for adult builders have been announced, with accurate recreations of the NASA Artemis rocket and the whole Milky Way.

It’s interesting timing, that just as NASA reestablishes contact with the Voyager 1 probe – the most distant man-made object in the universe – Lego has announced two major new space sets based on real.

Lego has always made sets based on real spaceships, as well as imaginary ones, but this year they’re pushing the space theme further by releasing sets in themes that don’t normally deal with the subject, such as Friends and Duplo.

For adults though there are two brand new 18+ sets: the NASA Artemis Space Launch System and the whole of the Milky Way in Lego form…

The two sets have both been created in conjunction with NASA but they’re both very different, with the Artemis model being a highly detailed recreation of the rocket and the launch tower.

On the other hand, the Milky Way Galaxy is a 3D art piece, that can be displayed on the wall, and is made up of hundreds of the smallest size of Lego pieces. When you look at the image from a short distance away it looks just like our galaxy, complete with a little sign saying, ‘you are here’!

The Artemis Space Launch System is made up of 3,601 pieces and includes the multistage rocket and two solid fuel boosters, that come apart just like the real thing.

There’s also an equally accurate model of the Orion spacecraft, powered by the European Space Agency’s European Service Module, that fits inside – although it can also be displayed with its own plaque and foldout solar panels.

The tower looks just like the real one in Cape Canaveral and has supports for the rocket, a crew bridge, and retractable umbilicals. The whole model, with the rocket in place, works out at 70cm tall and 30cm deep.

The NASA Artemis Space Launch System is set number 10341 and will be released on May 18 for £219.99. Lego Insiders (which you can sign up as for free ) can purchase it early, on May 15.

The Milky Way set is a completely different prospect and is made up of 3,091 pieces, that build up multiple layers to create a 3D effect.

Although the pieces are recoloured plants and studs, and other innocuous Lego parts, they’re used to cleverly recreate the shape and colours of our home galaxy, including specific landmarks such as the star TRAPPIST-1, which famously has seven planets orbiting it; the Pleiades star cluster, which is the most easily seen by the naked eye; the Crab Nebula supernova remnant; and the famous Pillars of Creation.

Because it’s such a complicated build, the model is made up of five different panels, so a group of friends or family can work together, each with their own building instructions.

At the same time, you can also listen to a special podcast featuring Lego designers and University of Leicester’s Dr Maggie Aderin-Pocock and former aerospace engineer Camille Bergin, aka Galactic Gal.

Lego Art The Milky Way Galaxy, set number 31212, will also be released on May 18, with early access for Lego Insiders. It costs £169.99 and the completed model measures 65cm long by 40cm high.

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Universe Today

Space and astronomy news

Voyager and Pioneer’s Grand Tour of the Milky Way

During the early 1990s, NASA’s Pioneer 10 and 11 probes became the first robotic missions to venture beyond Neptune. In 2012 and 2018, the Voyager 1 and 2 missions went even farther by crossing the heliopause and entering interstellar space. Eventually, these probes may reach another star system, where their special cargo (the Pioneer Plaques and the Golden Records ) could find their way into the hands of another species.

Which raises an important question: where might these spacecraft eventually wander? To address this, Coryn Bailer-Jones of the Max Planck Institute for Astronomy and Davide Farnocchia of NASA’s Jet Propulsion Laboratory recently conducted a study that examined which star systems the Voyager and Pioneer probes will likely encounter as they drift through the Milky Way over the next few million years…

The study, “ Future Stellar Flybys of the Voyager and Pioneer Spacecraft “, recently appeared in the journal Research Notes of the American Astronomical Society (RNAAS). For the sake of this study, Bailer-Jones and Farnocchia used data from the second Gaia data release (GDR2) and the SIMBAD astronomical database to determine the fate of these spacecraft.

“They will just continue to orbit through the Galaxy,” Bailer-Jones told Universe Today via email. “They are extremely unlikely to ever collide with a star. They are likely to be deflected a little bit now and again by stars and molecular clouds but would remain bound to the Galaxy for many, many billions of years.”

The story of Pioneer 10 and 11 began in 1972 and 73, respectively, when they were both launched towards Jupiter. Over the next few years, these two probes accomplished a number of firsts. Between them, they were the first robotic spacecraft to cross the Main Asteroid Belt , to encounter Jupiter and its system of moons, Saturn and its system of moons, and achieve an escape velocity that would allow them to leave the Solar System.

The story of Voyager 1 and 2 began a few years later, with both spacecraft launching from Earth in 1977 to take advantage of the favorable alignment between Jupiter, Saturn, Uranus and Neptune. After exploring Jupiter and Saturn, Voyager 1 continued on to the edge of the Solar System and entered the interstellar medium by 2012. Voyager 2 , meanwhile, visited Uranus and Neptune as well before joining Voyager 1 in interstellar space by 2018.

Fittingly, all of the spacecraft carried a message for other sentient species, should any come across them in the future. In the case of the Pioneer probes, this took the form of the Pioneer Plaque, which was designed by famed SETI researchers Carla Sagan and Frank Drake. These plaques featured the nude figures of a man and woman along with several symbols designed to provide information about the origin of the spacecraft.

The Voyager probes took things a step further with the Golden Record, which were designed by Carl Sagan and his colleagues to act as a message for other intelligent species – or a time-capsule for humanity in the far future. These 30 cm (12 in) golden phonographs contained pictures and sounds of Earth, along with symbolic directions on the cover for playing the record and data detailing the location of Earth.

Given that these craft were always intended to explore beyond our Solar System, and act as possible interstellar messengers, one can’t help but be curious where they might end up. Even though all four spacecraft will have long-ceased operations at that time (NASA lost contact with Pioneer 10 and 11 in 2003 and 1995, respectively), the spacecraft could still be picked up by interested parties. The only question is, where might this happen?

To determine this, Bailer-Jones and Farnocchia relied on the same techniques used in a previous study to trace the origin and future encounters of the interstellar object ‘Oumuamua . As Bailer-Jones explained, this consisted of three steps:

“[One,] identify in what direction and with what speed the spacecraft are leaving the solar system. (This is done by taking into account the gravity of all the planets in the solar system, as well as the Sun.) [Two,] map the motions of the spacecraft and the stars from Gaia into the future over millions of years. This takes into account a model for the gravity of the Galaxy as a whole. [Third,] identify which stars the spacecraft come close to, and when.”

Using a combination of Gaia and SIMBAD data, they calculated which stars the probes were most likely to have a close encounter with – pass within 1 parsec (3.26 light years) of. For instance, they found that both the Voyager missions and Pioneer 11 will encounter Proxima Centauri – the closest star system to our own with one potentially habitable planet (Proxima b) – on their current headings.

Another popular future destination is Ross 248, a red dwarf star that is approximately 10 light-years from Earth in the constellation Andromeda. Both Voyager 2 and Pioneer 10 are expected to pass within a parsec of this star in the coming centuries. And then there is Gliese 445, another red dwarf star located 17.6 light years from Earth in the constellation Camelopardalis, which Voyager 1 and Pioneer 11 will visit someday.

While this study was mainly motivated by curiosity, it does raise some important issues relating to interstellar exploration. These questions are becoming increasingly relevant in an age where human space exploration is once again ramping up, our knowledge of exoplanets is growing exponentially, and scientists are once again contemplating how me might visit distant worlds someday. As Bailer-Jones put it:

“This is mostly a bit of fun, but it also highlights how long it takes spacecraft to get to the nearest stars. But beyond this, one day we will (hopefully) be in a position to send spacecraft out much faster with the primary mission to investigate nearby stars. There are serious, if low level, studies taking place looking into ways of doing this, e.g. with laser sails, or nuclear powered rockets. It’s still in the future and beyond the limits of our current technology, but not unimaginable. Perhaps with an hundred years.”

As we discussed in a previous article , traveling to even the nearest star in our galaxy would require an incredibly amount of time, energy and resources. But considering how much of an accomplishment it would be to visit another star system, there is no shortage of proponents, scientists, theorists, and enthusiasts looking to make this happen.

Who knows? Maybe someday we might actually be able to send missions that could run into our first interstellar explorers. How cool would that be? On the other hand, it’s encouraging to know that human spacecraft will travel to nearby stars, regardless of whether or not humans do. So even if humanity never sends crewed spacecraft to another star, something of ourselves will visit them no matter what.

Further Reading: RNAAS

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Voyager 1 talking to Earth again after NASA engineers 24 billion kilometres away devise software fix

NASA's Voyager 1 probe — the most distant man-made object in the universe — is returning usable information to ground control following months of spouting gibberish, the US space agency says.

The spaceship stopped sending readable data back to Earth on November 14, 2023, even though controllers could tell it was still receiving their commands.

In March, teams working at NASA's Jet Propulsion Laboratory discovered that a single malfunctioning chip was to blame.

They then had to devise a clever coding fix that worked within the tight memory constraints of its 46-year-old computer system.

"There was a section of the computer memory no longer working," project leader Dr Linda Spilker told the ABC.

"So we had to reprogram what was in that memory, move it to a different location, link everything back together and send everything up in a patch.

"And then on Saturday morning, we watched as Voyager 1 sent its first commands back and we knew we were back in communication once again."

Dr Spilker said they were receiving engineering data, so they knew the health and safety of the spacecraft.

"The next step is going to be to develop a patch so we can send back the science data," she said.

"That will really be exciting, to once again learn about interstellar space and what has been going on there that we've missed since November."

Dr Spilker said Voyager sent back data in real time, so the team had no facility to retrieve data covering the time since transmission was lost.

Launched in 1977, Voyager 1 was mankind's first spacecraft to enter the interstellar medium , in 2012, and is currently more than 24 billion kilometres from Earth.

Messages sent from Earth take about 22.5 hours to reach the spacecraft.

Its twin, Voyager 2, also left the solar system in 2018 as it was tracked by Australia's Parkes radio telescope.

Australia was also vital to a 2023 search for Voyager 2 after signals were lost, with Canberra's Deep Space Communication Complex monitoring for signals and then sending a successful command to shift the spacecraft's antenna 2 degrees . 

Both Voyager spacecraft carry " Golden Records ": 12-inch, gold-plated copper disks intended to convey the story of our world to extraterrestrials.

These include a map of our solar system, a piece of uranium that serves as a radioactive clock allowing recipients to date the spaceship's launch, and symbolic instructions that convey how to play the record.

The contents of the record, selected for NASA by a committee chaired by legendary astronomer Carl Sagan, include encoded images of life on Earth, as well as music and sounds that can be played using an included stylus.

Their power banks were expected to be depleted sometime after 2025, but Dr Spilker said several systems had been turned off, so they were hopeful the two spacecraft would function into the 2030s.

They will then continue to wander the Milky Way, potentially for eternity, in silence.

• X (formerly Twitter)

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Inside NASA's 5-month fight to save the Voyager 1 mission in interstellar space

After working for five months to re-establish communication with the farthest-flung human-made object in existence, NASA announced this week that the Voyager 1 probe had finally phoned home.

For the engineers and scientists who work on NASA’s longest-operating mission in space, it was a moment of joy and intense relief.

“That Saturday morning, we all came in, we’re sitting around boxes of doughnuts and waiting for the data to come back from Voyager,” said Linda Spilker, the project scientist for the Voyager 1 mission at NASA’s Jet Propulsion Laboratory in Pasadena, California. “We knew exactly what time it was going to happen, and it got really quiet and everybody just sat there and they’re looking at the screen.”

When at long last the spacecraft returned the agency’s call, Spilker said the room erupted in celebration.

“There were cheers, people raising their hands,” she said. “And a sense of relief, too — that OK, after all this hard work and going from barely being able to have a signal coming from Voyager to being in communication again, that was a tremendous relief and a great feeling.”

The problem with Voyager 1 was first detected in November . At the time, NASA said it was still in contact with the spacecraft and could see that it was receiving signals from Earth. But what was being relayed back to mission controllers — including science data and information about the health of the probe and its various systems — was garbled and unreadable.

That kicked off a monthslong push to identify what had gone wrong and try to save the Voyager 1 mission.

Spilker said she and her colleagues stayed hopeful and optimistic, but the team faced enormous challenges. For one, engineers were trying to troubleshoot a spacecraft traveling in interstellar space , more than 15 billion miles away — the ultimate long-distance call.

“With Voyager 1, it takes 22 1/2 hours to get the signal up and 22 1/2 hours to get the signal back, so we’d get the commands ready, send them up, and then like two days later, you’d get the answer if it had worked or not,” Spilker said.

The team eventually determined that the issue stemmed from one of the spacecraft’s three onboard computers. Spilker said a hardware failure, perhaps as a result of age or because it was hit by radiation, likely messed up a small section of code in the memory of the computer. The glitch meant Voyager 1 was unable to send coherent updates about its health and science observations.

NASA engineers determined that they would not be able to repair the chip where the mangled software is stored. And the bad code was also too large for Voyager 1's computer to store both it and any newly uploaded instructions. Because the technology aboard Voyager 1 dates back to the 1960s and 1970s, the computer’s memory pales in comparison to any modern smartphone. Spilker said it’s roughly equivalent to the amount of memory in an electronic car key.

The team found a workaround, however: They could divide up the code into smaller parts and store them in different areas of the computer’s memory. Then, they could reprogram the section that needed fixing while ensuring that the entire system still worked cohesively.

That was a feat, because the longevity of the Voyager mission means there are no working test beds or simulators here on Earth to test the new bits of code before they are sent to the spacecraft.

“There were three different people looking through line by line of the patch of the code we were going to send up, looking for anything that they had missed,” Spilker said. “And so it was sort of an eyes-only check of the software that we sent up.”

The hard work paid off.

NASA reported the happy development Monday, writing in a post on X : “Sounding a little more like yourself, #Voyager1.” The spacecraft’s own social media account responded , saying, “Hi, it’s me.”

So far, the team has determined that Voyager 1 is healthy and operating normally. Spilker said the probe’s scientific instruments are on and appear to be working, but it will take some time for Voyager 1 to resume sending back science data.

Voyager 1 and its twin, the Voyager 2 probe, each launched in 1977 on missions to study the outer solar system. As it sped through the cosmos, Voyager 1 flew by Jupiter and Saturn, studying the planets’ moons up close and snapping images along the way.

Voyager 2, which is 12.6 billion miles away, had close encounters with Jupiter, Saturn, Uranus and Neptune and continues to operate as normal.

In 2012, Voyager 1 ventured beyond the solar system , becoming the first human-made object to enter interstellar space, or the space between stars. Voyager 2 followed suit in 2018.

Spilker, who first began working on the Voyager missions when she graduated college in 1977, said the missions could last into the 2030s. Eventually, though, the probes will run out of power or their components will simply be too old to continue operating.

Spilker said it will be tough to finally close out the missions someday, but Voyager 1 and 2 will live on as “our silent ambassadors.”

Both probes carry time capsules with them — messages on gold-plated copper disks that are collectively known as The Golden Record . The disks contain images and sounds that represent life on Earth and humanity’s culture, including snippets of music, animal sounds, laughter and recorded greetings in different languages. The idea is for the probes to carry the messages until they are possibly found by spacefarers in the distant future.

“Maybe in 40,000 years or so, they will be getting relatively close to another star,” Spilker said, “and they could be found at that point.”

Denise Chow is a reporter for NBC News Science focused on general science and climate change.

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No matter what you're doing right now – sitting, standing, walking – you're moving.

Specifically, you're moving at least four different ways.

First, Earth is spinning around on its axis at about 1,000 miles per hour right now, or about 1,600 kilometers per hour. This rotation is the reason we have days. Second, Earth and other planets in our solar system are orbiting the sun. Our planet does that at around 67,000 miles per hour, or about 108,000 kilometers per hour. That's why we have years. And third, you're moving because the sun and the rest of our solar system is orbiting the center of the Milky Way galaxy at over 500,000 miles per hour, or 828,000 kilometers per hour.

On top of all that, you're moving because the entire universe is expanding outward. All the time.

But in the 1970s, astrophysicists noticed that something was off about our galactic neighborhood, or Local Group. The whole clump of neighboring galaxies were being pulled off course at over one million miles per hour, towards something we couldn't see.

They called this region the Great Attractor. But their ability to study it was limited.

"The Milky Way has millions and millions of stars and a lot of dust, which is blocking all that information that we could be measuring in that direction. So our own galaxy's blocking the Great Attractor," says Jorge Moreno , a computational astrophysicist at Pomona College. This area we cannot see is known to researchers as the Zone of Avoidance.

Scientists still don't know the full details of what and exactly how the Milky Way and its neighboring galaxies off course, but there have been several candidates over the last few decades.

Most recently, the prime suspect is the supercluster Laniakea, which is Hawaiian for 'immense heaven' or 'immeasurable heaven.'

Curious about other cosmic mysteries? Email us at [email protected] .

Listen to Short Wave on Spotify , Apple Podcasts and Google Podcasts .

Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave .

Today's episode was produced by Rachel Carlson. It was edited by Rebecca Ramirez. Rebecca, Rachel and Regina checked the facts. Maggie Luthar was the audio engineer.

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Well, hello, Voyager 1! The venerable spacecraft is once again making sense

After a nasty computer glitch five months ago, Voyager 1 is once again able to communicate with Earth in a way that mission operators can understand.

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Well, hello, Voyager 1! The venerable spacecraft is once again making sense

Nell Greenfieldboyce

Members of the Voyager team celebrate at NASA's Jet Propulsion Laboratory after receiving data about the health and status of Voyager 1 for the first time in months. NASA/JPL-Caltech hide caption

Members of the Voyager team celebrate at NASA's Jet Propulsion Laboratory after receiving data about the health and status of Voyager 1 for the first time in months.

NASA says it is once again able to get meaningful information back from the Voyager 1 probe, after months of troubleshooting a glitch that had this venerable spacecraft sending home messages that made no sense.

The Voyager 1 and Voyager 2 probes launched in 1977 on a mission to study Jupiter and Saturn but continued onward through the outer reaches of the solar system. In 2012, Voyager 1 became the first spacecraft to enter interstellar space, the previously unexplored region between the stars. (Its twin, traveling in a different direction, followed suit six years later.)

Voyager 1 had been faithfully sending back readings about this mysterious new environment for years — until November, when its messages suddenly became incoherent .

NASA's Voyager 1 spacecraft is talking nonsense. Its friends on Earth are worried

It was a serious problem that had longtime Voyager scientists worried that this historic space mission wouldn't be able to recover. They'd hoped to be able to get precious readings from the spacecraft for at least a few more years, until its power ran out and its very last science instrument quit working.

For the last five months, a small team at NASA's Jet Propulsion Laboratory in California has been working to fix it. The team finally pinpointed the problem to a memory chip and figured out how to restore some essential software code.

"When the mission flight team heard back from the spacecraft on April 20, they saw that the modification worked: For the first time in five months, they have been able to check the health and status of the spacecraft," NASA stated in an update.

The usable data being returned so far concerns the workings of the spacecraft's engineering systems. In the coming weeks, the team will do more of this software repair work so that Voyager 1 will also be able to send science data, letting researchers once again see what the probe encounters as it journeys through interstellar space.

After a 12.3 billion-mile 'shout,' NASA regains full contact with Voyager 2

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Stephen Clark, Ars Technica

How NASA Repaired Voyager 1 From 15 Billion Miles Away

Engineers have partially restored a 1970s-era computer on NASA's Voyager 1 spacecraft after five months of long-distance troubleshooting , building confidence that humanity's first interstellar probe can eventually resume normal operations.

Several dozen scientists and engineers gathered Saturday in a conference room at NASA's Jet Propulsion Laboratory, or connected virtually, to wait for a new signal from Voyager 1. The ground team sent a command up to Voyager 1 on Thursday to recode part of the memory of the spacecraft's Flight Data Subsystem (FDS) , one of the probe's three computers.

“In the minutes leading up to when we were going to see a signal, you could have heard a pin drop in the room,” said Linda Spilker, project scientist for NASA's two Voyager spacecraft at JPL. “It was quiet. People were looking very serious. They were looking at their computer screens. Each of the subsystem (engineers) had pages up that they were looking at, to watch as they would be populated.”

Finally, a Breakthrough

Launched nearly 47 years ago, Voyager 1 is flying on an outbound trajectory more than 15 billion miles (24 billion kilometers) from Earth, and it takes 22.5 hours for a radio signal to cover that distance at the speed of light. This means it takes nearly two days for engineers to uplink a command to Voyager 1 and get a response.

In November, Voyager 1 suddenly stopped transmitting its usual stream of data containing information about the spacecraft's health and measurements from its scientific instruments. Instead, the spacecraft's datastream was entirely unintelligible. Because the telemetry was unreadable, experts on the ground could not easily tell what went wrong. They hypothesized the source of the problem might be in the memory bank of the FDS.

There was a breakthrough last month when engineers sent up a novel command to “poke” Voyager 1's FDS to send back a readout of its memory. This readout allowed engineers to pinpoint the location of the problem in the FDS memory . The FDS is responsible for packaging engineering and scientific data for transmission to Earth.

After a few weeks, NASA was ready to uplink a solution to get the FDS to resume packing engineering data. This datastream includes information on the status of the spacecraft—things like power levels and temperature measurements. This command went up to Voyager 1 through one of NASA's large Deep Space Network antennae on Thursday.

Then, the wait for a response. Spilker, who started working on Voyager right out of college in 1977, was in the room when Voyager 1's signal reached Earth on Saturday.

“When the time came to get the signal, we could clearly see all of a sudden, boom, we had data, and there were tears and smiles and high fives,” she told Ars. “Everyone was very happy and very excited to see that, hey, we're back in communication again with Voyager 1. We're going to see the status of the spacecraft, the health of the spacecraft, for the first time in five months.”

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Throughout the five months of troubleshooting, Voyager's ground team continued to receive signals indicating the spacecraft was still alive. But until Saturday, they lacked insight into specific details about the status of Voyager 1.

“It’s pretty much just the way we left it,” Spilker said. “We're still in the initial phases of analyzing all of the channels and looking at their trends. Some of the temperatures went down a little bit with this period of time that's gone on, but we're pretty much seeing everything we had hoped for. And that's always good news.”

Relocating Code

Through their investigation, Voyager's ground team discovered that a single chip responsible for storing a portion of the FDS memory had stopped working, probably due to either a cosmic ray hit or a failure of aging hardware. This affected some of the computer's software code.

“That took out a section of memory,” Spilker said. “What they have to do is relocate that code into a different portion of the memory, and then make sure that anything that uses those codes, those subroutines, know to go to the new location of memory, for access and to run it.”

Only about 3 percent of the FDS memory was corrupted by the bad chip, so engineers needed to transplant that code into another part of the memory bank. But no single location is large enough to hold the section of code in its entirety, NASA said.

So the Voyager team divided the code into sections for storage in different places in the FDS. This wasn't just a copy-and-paste job. Engineers needed to modify some of the code to make sure it will all work together. “Any references to the location of that code in other parts of the FDS memory needed to be updated as well,” NASA said in a statement.

Newer NASA missions have hardware and software simulators on the ground, where engineers can test new procedures to make sure they do no harm when they uplink commands to the real spacecraft. Due to its age, Voyager doesn't have any ground simulators, and much of the mission's original design documentation remains in paper form and hasn't been digitized.

“It was really eyes-only to look at the code,” Spilker said. “So we had to triple check. Everybody was looking through and making sure we had all of the links coming together.”

This was just the first step in restoring Voyager 1 to full functionality. “We were pretty sure it would work, but until it actually happened, we didn't know 100 percent for sure,” Spilker said.

“The reason we didn’t do everything in one step is that there was a very limited amount of memory we could find quickly, so we prioritized one data mode (the engineering data mode), and relocated only the code to restore that mode,” said Jeff Mellstrom, a JPL engineer who leads the Voyager 1 “tiger team” tasked with overcoming this problem.

“The next step, to relocate the remaining three actively used science data modes, is essentially the same,” Mellstrom said in a written response to Ars. “The main difference is the available memory constraint is now even tighter. We have ideas where we could relocate the code, but we haven’t yet fully assessed the options or made a decision. These are the first steps we will start this week.”

It could take “a few weeks” to go through the sections of code responsible for packaging Voyager 1's science data in the FDS, Spilker said.

That will be the key payoff, Spilker said. Voyager 1 and its twin spacecraft, Voyager 2, are the only operating probes flying in the interstellar medium, the diffuse gas between the stars. Their prime missions are long over. Voyager 1 flew by Jupiter and Saturn in 1979 and 1980, then got a gravitational boost toward the outer edge of the Solar System. Voyager 2 took a slower trajectory and encountered Jupiter, Saturn, Uranus, and Neptune.

For the past couple of decades, NASA has devoted Voyager's instruments to studying cosmic rays, the magnetic field, and the plasma environment in interstellar space. They're not taking pictures anymore. Both probes have traveled beyond the heliopause, where the flow of particles emanating from the Sun runs into the interstellar medium.

But any scientific data collected by Voyager 1 since November 14 has been lost. The spacecraft does not have the ability to store science data onboard. Voyager 2 has remained operational during the outage of Voyager 1.

Scientists are eager to get their hands on Voyager 1's science data again. “With the results we got on Saturday, we have new confidence that we can put together the pieces we need to now get back the science data,” Spilker said.

“One thing I'm particularly excited about—there's this feature in the Voyager 1 data. We nicknamed it Pressure Front 2,” Spilker said. “Pressure Front 2 is a jump in both the density of the plasma around the spacecraft and the magnetic field. It's lasted for three-and-a-half years.”

“We'd like to see, is this still there?” she continued. “It's different from what we've seen in the past, and we're trying to figure out, is it some influence coming from the Sun, or is it actually something coming from interstellar space that's creating this feature? So we'd like to see it again, get more data, and be able to study it more carefully.”

This story originally appeared on Ars Technica .

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• The Contents
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• Where Are They Now
• Frequently Asked Questions
• Q & A with Ed Stone

golden record

Where are they now.

• frequently asked questions
• Q&A with Ed Stone

News | October 23, 1991

Voyagers continues to return data from the edges of the milky way.

More than two years after Voyager 2 looked Neptune's Great Dark Spot in the eye and darted past the frozen surface of its moon Triton, both Voyager spacecraft are continuing to return data about interplanetary space and some of our stellar neighbors near the edges of the Milky Way.

After the Voyager spacecraft flew by the four giant outer planets -- Jupiter, Saturn, Uranus and Neptune -- their mission might have been over. But, in fact, these 14-year-old twins are just beginning a new phase of their journey, called the Voyager Interstellar Mission (VIM).

As the Voyagers cruise gracefully in the solar wind, their fields, particles and waves instruments are studying the space around them while searching for the elusive heliopause -- the outer edge of our solar system.

The heliopause is the outermost boundary of the solar wind, where the interstellar medium restricts the outward flow of the solar wind and confines it within a magnetic bubble called the heliosphere. The solar wind is made up of electrically charged atomic particles, composed primarily of ionized hydrogen, that stream outward from the Sun. "The termination shock is the first signal that we are approaching the heliopause. It's the area where the solar wind starts slowing down," said Voyager Project Scientist and JPL's Director, Dr. Edward C. Stone. Mission scientists now anticipate that the spacecraft may cross the termination shock by the end of the century. Exactly where the heliopause is remains a mystery. Its long been thought to be located some 75 to 150 astronomical units (AU) from the Sun. (One AU is equal to 150 million kilometers (93 million miles), or the distance from the Earth to the Sun.) Any speculation about where the heliopause is or what it is like, has come only from computer models and theories. "Voyager 1 is likely to return the first direct evidence from the heliopause and what lies beyond it," Stone said.

Yet the Voyagers are not sitting idly by as they wait to cross over into interstellar space. Both spacecraft are involved in an extensive program of ultraviolet astronomy that allows them to study active galaxies, quasars and white dwarf stars, in ways unlike any other spacecraft or telescope in existence.

Voyager's ultraviolet spectrometers are the only way scientists can currently observe celestial objects in a unique region in the short end of the ultraviolet portion of the electromagnetic spectrum. "Voyager's instruments allow it to observe things at wavelengths that are for the most part unavailable to other spacecraft," said Dr. Jay Holberg, a member of Voyager's ultraviolet subsystem team.

The Voyagers have become space-based ultraviolet observatories and their unique location in the universe gives astronomers the best vantage point they have ever had for looking at celestial objects that emit ultraviolet radiation. "The light that Voyager is sensitive to has to be observed in outer space," said Holberg.

Voyager's ultraviolet instruments are best suited to study the two extreme phases of a star's life -- its birth and its death. Thus the Voyagers are currently gathering data on early blue stars as well as other white dwarf stars nearing the end of their lifetime. "Voyager is helping us get a better handle on exactly how much energy these hot stars emit," Holberg said.

Now that Voyager's primary mission of exploring the outer planets is over, there are fewer constraints on the science team when it comes to programming the spacecrafts' observations. "We can sit on these things for very long periods of time and watch these stars go through their phases," Holberg said.

Stars can be very active, but also unpredictable. "We don't know when a star will do something. If we want to sit there and wait, we can do it in the hopes that the star will go through an outburst and Voyager will be there to observe it," he continued. Voyager can now stare at an object for days and even weeks at a time to thoroughly map it and the region around it.

Since the beginning of the interstellar mission, the Voyager project has been conducting a guest observer program which allows astronomers from around the world to make proposals and apply for time to use the Voyager ultraviolet spectrometer in much the same way that astronomers apply for time at ground-based observatories. This program enables scientists to make simultaneous observations of the same object using Voyager and ground-based telescopes.

The cameras on the spacecraft have been turned off and the ultraviolet instrument is the only experiment on the scan platform that is still functioning. Voyager scientists expect to continue to receive data from the ultraviolet spectrometers at least until the year 2000. At that time, there will not be enough electrical power for the heaters to keep the ultraviolet instrument warm enough to operate.

Yet there are several other fields and particle instruments that can continue to send back data as long as the spacecraft stay alive. They include: the cosmic ray subsystem, the low-energy charged particle instrument, the magnetometer, the plasma subsystem, the plasma wave subsystem and the planetary radio astronomy instrument. Barring any catastrophic events, JPL should be able to retrieve this information for at least the next 20 and perhaps even the next 30 years.

"In exploring the four outer planets, Voyager has already had an epic journey of discovery. Even so, their journey is less than half over with more discoveries awaiting the first contact with interstellar space," Stone said. "The Voyagers revealed how limited our imaginations really were about our solar system, and I expect that as they continue toward interstellar space, they will again surprise us with unimagined discoveries of this never-before-visited place which awaits us beyond our planetary neighborhood."

Voyager 1 is now 7 billion kilometers (4.3 billion miles) from Earth, traveling at a heliocentric velocity of 63,800 km/hr (39,700 mph). Voyager 2, traveling in the opposite direction from its twin, is 5.3 billion kilometers (3.3 billion miles) from Earth with a heliocentric velocity of 59,200 km/hr (36,800 mph).

The Voyager Interstellar Mission is managed by JPL and sponsored by NASA's Office of Space Science and Applications, Washington, DC.