voyager 1 space probe in 1990

On February 14, 1990, the Voyager 1 spacecraft saw Earth from a distance of nearly four billion miles, capturing a view of our planet later described by scientist Carl Sagan as a “Pale Blue Dot.”

The first person to see the 'Pale Blue Dot' image still has it stashed in her closet

"Somewhere in that little bright speck, I was sitting at my desk."

Thirty years ago today, NASA’s Voyager 1 spacecraft had already traveled well beyond the realm of the planets and was shooting toward interstellar space. Nearly a billion miles farther out than Neptune, it suddenly swiveled around and stared backward. There, pressed onto a star-studded sky, were a dazzling array of planets—ringed Saturn, giant Jupiter, bright white Venus, and a stunningly pale, blue, watery Earth.

On Valentine’s Day in 1990, Voyager methodically assembled a family portrait of the solar system’s many worlds. Carl Sagan had first proposed the observation nearly a decade earlier, only to have the idea rejected over and over again for several reasons, including concerns that the images wouldn’t provide any scientific value. But Voyager was hurtling toward the edge of the solar system, and its cameras were imminently shutting down. From its perch nearly four billion miles away, the spacecraft had one last chance to snap a photo of its home planet.

“Really, this was the last-ever opportunity,” says the Planetary Science Institute’s Candy Hansen , who helped plan the photo sequence. (Now, Hansen is the force behind JunoCam , which is riding aboard NASA’s Juno spacecraft and returning ethereal, gorgeous pictures of Jupiter.)

At the time, Hansen was part of the Voyager imaging team at NASA’s Jet Propulsion Laboratory . Her job, as the experiment representative, included planning the spacecraft’s observations and then checking the resulting images to make sure everything worked as planned—which meant that of the billions of people on Earth, she was the first human to see the image now referred to as the Pale Blue Dot .

“It was really quite overwhelming to think about,” Hansen recalls. “That our little spacecraft from so far away—that this was a picture of home, and somewhere in that little bright speck, I was sitting at my desk.”

Thirty-four minutes after capturing Earth, Voyager’s cameras turned off forever. In the now-iconic image, a small, unobtrusive pinprick of light hovers amid a ray of scattered sunlight, appearing cosmically inconsequential. The photo’s legacy is that it has inspired the opposite response: a deep recognition of Earth’s importance, its fragility, its uniqueness.

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“That’s here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives … on a mote of dust suspended in a sunbeam,” Sagan later wrote in his book , Pale Blue Dot . “In our obscurity, in all this vastness, there is no hint that help will come from elsewhere to save us from ourselves.”

Hansen spoke with National Geographic about what the Pale Blue Dot meant to her then, what it means to her now, and where she’s stashed the original photograph. ( This interview has been edited for length and clarity. )

How did you end up being the first human to see the Pale Blue Dot?

I went to work for the Voyager imaging team in 1977, and I started out as the assistant to the assistant experiment representative. The imaging team, who were a bunch of scientists scattered around the country, relied on the experiment rep at JPL to implement everything on their behalf.

My main job was planning for all of our observations and camera commands for the flybys themselves. I had been helping Carl with this observation since its beginning. It was his vision. But as the person on the scene at JPL, it was my job to fill out the form that says, “Here’s the request, here’s what we want to do,” go to the meetings, just do the legwork.

We’d gotten turned down a bunch of times, but then finally in 1989, realizing that really, this was the last-ever opportunity, we got permission to go forward with this observation. So I had been involved in planning the observation as well as ultimately looking at the pictures.

How did you all design the observation?

One of the sequence designers and I sat down and looked at what we could do. Carl’s idea was to mosaic the whole sky and have the whole star background of all of the planets—but we just didn’t have enough space on the tape recorder. So we came up with a picture of every planet, in color, and some stars. We did this kind of hobby-horse-looking thing that connected all the planets with wide-angle images, and then we did the images of the sun.

And then, finally, the pictures started to hit the ground.

So you were checking the images and making sure the observations had worked.

Yes. And because it was first in, first out on the tape recorder, and we had started out at Neptune, we were working our way in. I was looking first at the Neptune images, and it was like, Oh yeah, OK, there’s Neptune, and then Uranus—oh yeah, there’s Uranus, and then Saturn, and then Jupiter—and those are relatively large planets, so they were relatively large little spots.

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I could recognize almost immediately the blemishes and the specks of dust that are in every image, so I could pretty quickly pull up an image and identify “Blemish, blemish, dust, ah, there’s Neptune,” and I was just very systematically working my way in.

And when I got to the picture that should have had the Earth in it, I didn’t see it at first.

I checked the other two filters, and I was like, How could we have missed the Earth? We got all these other planets, and our whole idea was to capture the Earth! That was a moment of terror, panic, that something had—after all these years when we finally had this opportunity—that something had gotten screwed up.

So I’m sitting there thinking, What are we going to do? What are we going to say? And then I noticed, Oh wait, over in this ray of scattered light, there’s a bright spot that I don’t recognize as dust or a blemish. So I thought, OK, let me get the other two filters. Sure enough, it was in all three images, and I knew positively it wasn’t an artifact or anything else because I knew how to recognize those.

It was the Earth.

I just sat there. It was, honestly, it was really quite overwhelming to think about. That our little spacecraft was so far away, that this was a picture of home, and somewhere in that little bright speck, I was sitting at my desk. And it was so dramatic with it being in that ray of scattered light.

Logically, I knew this was just scattered light in the optics. I knew that. But my heart was like, Oh it looks so special. The sun is shining on us! So then after I composed myself, I started making calls to let people know that we had gotten it, it looked good, all three colors, and then everything else happened after that.

Did you know that you were looking at an image that would have such an impact?

I felt it, yeah. I always did. I’d had to, in a sense, sell the observation. So I had definitely given it some thought. But giving it some thought and the actual emotional impact are two different things.

In coming back to it now, I’ve really come to realize how timeless that image is. When we took it in 1990, the Cold War was still going on. It was still the Soviet Union and the United States with nuclear warheads pointed at each other. So the message at that point in time was, Let’s not screw up the home planet by nuking each other.

And today, it’s still every bit as relevant. Let’s not screw up our home world by cooking our atmosphere—climate change. In that regard, it’s really timeless. It’s the sense that we only have one home. Mars is really not that hospitable. And neither is the moon. We have one home world, and we really do need to take care of it.

I think people kind of know that conceptually, but actually seeing Earth—and I’m thinking about Earthrise as well—seeing the planet as a whole seems to really drive that point home in an emotional way.

Yes. And that image, Earthrise, oh my god it is incredibly important to how we see ourselves.

When you look at the Pale Blue Dot today, do you still have the same kinds of reactions that you did when you first saw it?

Yes. I still get chills down my back. It’s that whole, a picture is worth a thousand words—well maybe that particular one is worth a million.

We put up the images in JPL’s von Kármán auditorium, and they took up a whole stretch of wall space, and they were just sort of mounted, the wide angles connecting together, and then the narrow angles of the planets themselves. And the person who was in charge of that, he told me one time that he always had to replace the picture of Earth, because people would come up and they would touch it. Isn’t that cool? That’s where we live!

I wonder how many images of Earth he had to replace.

I don’t know! Wouldn’t that be fun to find out?

Or where all of the originals are.

Oh those, I can tell you. They’re in a box in my closet.

Are you serious?

Yeah, I am. Not the digital data, of course, that’s in the archive. But all those original hard copies that we pinned up, that we had laying around, those are all in a box in my closet.

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Happy Birthday, 'Pale Blue Dot!' Famous Space Photo Turns 25

One of history's most iconic photos turns 25 years old Saturday (Feb. 14).

On Feb. 14, 1990, NASA's Voyager 1 spacecraft took a family portrait of the solar system, capturing Neptune, Uranus, Saturn, Jupiter, Venus and Earth — which showed up as a "pale blue dot" — in a single view.

The famous image "continues to inspire wonderment about the spot we call home," Voyager project scientist Ed Stone, of the California Institute of Technology in Pasadena, said in a NASA statement. [ 5 Facts About NASA's Far-Flung Voyager Spacecraft ]

The late astronomer Carl Sagan referenced and further immortalized the photo in the title of his 1994 book, "The Pale Blue Dot: A Vision of the Human Future in Space" (Random House). Sagan was part of the Voyager imaging team when the picture was taken.

Voyager 1 took the photo while located 40 astronomical units (AU) from Earth, NASA officials said. (One AU is the distance from Earth to the sun — about 93 million miles, or 150 million kilometers.)

Only three of the solar system's then-recognized nine planets failed to find a spot in the picture: Mars was too dark; Mercury was too close to the sun, and Pluto was too dim. (The International Astronomical Union demoted Pluto to "dwarf planet" status in 2006, in a decision that remains controversial today.)

Voyager 1 and its twin, Voyager 2, launched a few weeks apart in 1977 to conduct an unprecedented "grand tour" of the outer solar system. Together, the two probes gave researchers some of their first good looks at Jupiter, Saturn, Uranus and Neptune, as well as the moons of those big, gaseous planets.

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Both spacecraft then kept right on flying. In August 2012, Voyager 1 became the first man-made object to reach interstellar space ; Voyager 2, which took a different route through the solar system, should achieve the milestone soon as well.

The series of images that comprise the "pale blue dot" portrait were the last that Voyager 1 took. The probe's handlers turned Voyager 1's camera off to retask the computer controlling the camera for other purposes.

"After taking these images in 1990, we began our interstellar mission. We had no idea how long the spacecraft would last," Stone said in the statement .

Voyager 1 is now about 130 AU from Earth. If the probe tried to photograph Earth right now, the planet would appear about 10 times dimmer than in did back in February 1990, NASA officials said.

Follow Mike Wall on Twitter  @michaeldwall  and  Google+ . Follow us @Spacedotcom , Facebook  or Google+ . Originally published on  Space.com .

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].

Michael Wall is a Senior Space Writer with  Space.com  and joined the team in 2010. He primarily covers exoplanets, spaceflight and military space, but has been known to dabble in the space art beat. His book about the search for alien life, "Out There," was published on Nov. 13, 2018. Before becoming a science writer, Michael worked as a herpetologist and wildlife biologist. He has a Ph.D. in evolutionary biology from the University of Sydney, Australia, a bachelor's degree from the University of Arizona, and a graduate certificate in science writing from the University of California, Santa Cruz. To find out what his latest project is, you can follow Michael on Twitter.

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This Day In History : February 14

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“Pale Blue Dot” photo of Earth is taken

On Valentine's Day, 1990, 3.7 billion miles away from the sun, the Voyager 1 spacecraft takes a photograph of Earth. The picture, known as Pale Blue Dot , depicts our planet as a nearly indiscernible speck roughly the size of a pixel.

Launched on September 5, 1977, Voyagers 1 and 2 were charged with exploring the outer reaches of our solar system. It passed by Jupiter in March of 1979 and Saturn the following year. The gaps between the outer planets are so vast that it was another decade before it passed by Neptune and arrived at the spot where it was to take a series of images of the planets, known as the "Family Portrait" of our solar system.

Of the Family Portrait series, Pale Blue Dot was certainly the most memorable. The furthest image ever taken of Earth, it lent its name to popular astronomer Carl Sagan's 1994 book. Sagan, who advised the Voyager mission and had suggested the photo, wrote the following: "Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there—on a mote of dust suspended in a sunbeam."

Voyager 1's journey continues. In 1998, it became the most distant human-made object in space, and on August 25, 2012, it left the furthest reaches of the sun's magnetic field and solar winds, becoming the first man-made object in interstellar space. 

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45 years ago: voyager 1 begins its epic journey to the outer planets and beyond, johnson space center.

Forty-five years ago, the Voyager 1 spacecraft began an epic journey that continues to this day. The second of a pair of spacecraft, Voyager 1 lifted off on Sept. 5, 1977, 16 days after its twin left on a similar voyage. NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California, managed the two spacecraft on their missions to explore the outer planets. Taking advantage of a rare planetary alignment to use the gravity of one planet to redirect the spacecraft to the next, the Voyagers planned to use Jupiter’s gravity to send them on to explore Saturn and its large moon Titan. They carried sophisticated instruments to conduct their in-depth explorations of the giant planets. Both spacecraft continue to return data as they make their way out of our solar system and enter interstellar space.

In the 1960s, mission designers at JPL noted that the next occurrence of a once-every-175-year alignment of the outer planets would happen in the late 1970s. A spacecraft could take advantage of this opportunity to fly by Jupiter and use its gravity to bend its trajectory to visit Saturn, and repeat the process to also visit Uranus, Neptune, and Pluto. Launching several missions to visit each planet individually would take much longer and cost much more. The original plan to send two pairs of Thermoelectric Outer Planet Spacecraft on these Grand Tours proved too costly leading to its cancellation in 1971. The next year, NASA approved a scaled-down version of the project to send a pair of Mariner-class spacecraft in 1977 to explore just Jupiter and Saturn, with an expected five-year operational life. On March 7, 1977, NASA Administrator James C. Fletcher announced the renaming of these Mariner Jupiter/Saturn 1977 spacecraft as Voyager 1 and 2. Scientists held out hope that one of them could ultimately visit Uranus and Neptune, thereby fulfilling most of the original Grand Tour’s objectives – Pluto would have to wait several decades for its first visit.

Each Voyager carried a suite of 11 instruments to study the planets during each encounter and to learn more about interplanetary space in the outer reaches of the solar system, including: 

• An imaging science system consisting of narrow-angle and wide-angle cameras to photograph the planet and its satellites.
• A radio science system to determine the planet’s physical properties.
• An infrared interferometer spectrometer to investigate local and global energy balance and atmospheric composition.
• An ultraviolet spectrometer to measure atmospheric properties.
• A magnetometer to analyze the planet’s magnetic field and interaction with the solar wind.
• A plasma spectrometer to investigate microscopic properties of plasma ions.
• A low-energy charged particle device to measure fluxes and distributions of ions.
• A cosmic ray detection system to determine the origin and behavior of cosmic radiation.
• A planetary radio astronomy investigation to study radio emissions from Jupiter.
• A photopolarimeter to measure the planet’s surface composition.
• A plasma wave system to study the planet’s magnetosphere.

Voyager 1 lifted off on Sept. 5, 1977, atop a Titan IIIE-Centaur rocket from Launch Complex 41 at Cape Canaveral Air Force Station, now Cape Canaveral Space Force Station, in Florida. Two weeks after its launch, from a distance of 7.25 million miles, Voyager 1 turned its camera back toward its home planet and took the first single-frame image of the Earth-Moon system. The spacecraft successfully crossed the asteroid belt between Dec. 10, 1977, and Sept. 8, 1978.

Although Voyager 1 launched two weeks after its twin, it traveled on a faster trajectory and arrived at Jupiter four months earlier. Voyager 1 conducted its observations of Jupiter between Jan. 6 and April 13, 1979, making its closest approach of 216,837 miles from the planet’s center on March 5. The spacecraft returned 19,000 images of the giant planet, many of Jupiter’s satellites, and confirmed the presence of a thin ring encircling it. Its other instruments returned information about Jupiter’s atmosphere and magnetic field. Jupiter’s massive gravity field bent the spacecraft’s trajectory and accelerated it toward Saturn.

Voyager 1 began its long-range observations of Saturn on Aug. 22, 1980, passed within 114,500 miles of the planet’s center on Nov. 12, and concluded its studies on Dec. 14. Because of its interest to scientists, mission planners chose the spacecraft’s trajectory to make a close flyby of Saturn’s largest moon Titan – the only planetary satellite with a dense atmosphere – just before the closest approach to the planet itself. This trajectory, passing over Saturn’s south pole and bending north over the plane of the ecliptic, precluded Voyager 1 from making any additional planetary encounters. The spacecraft flew 4,033 miles from Titan’s center, returning images of its unbroken orange atmosphere and high-altitude blue haze layer. During the encounter, Voyager 1 returned 16,000 photographs, imaging Saturn, its rings, many of its known satellites and discovering several new ones, while its instruments returned data about Saturn’s atmosphere and magnetic field.

On Feb. 14, 1990, more than 12 years after it began its journey from Earth and shortly before controllers  permanently turned off its cameras to conserve power, Voyager 1 spun around and pointed them back into the solar system. In a mosaic of 60 images, it captured a “family portrait” of six of the solar system’s planets, including a pale blue dot called Earth more than 3.7 billion miles away. Fittingly, these were the last pictures returned from either Voyager spacecraft. On Feb. 17, 1998, Voyager 1 became the most distant human-made object, overtaking the Pioneer 10 spacecraft on their way out of the solar system. In February 2020, to commemorate the photograph’s 30th anniversary, NASA released a remastered version of the image of Earth as Pale Blue Dot Revisited .

On New Year’s Day 1990, both spacecraft officially began the Voyager Interstellar Mission as they inexorably made their escape from our solar system. On Aug. 25, 2012, Voyager 1 passed beyond the heliopause, the boundary between the heliosphere, the bubble-like region of space created by the Sun, and the interstellar medium. Its twin followed suit six years later. Today , 45 years after its launch and 14.6 billion miles from Earth, four of Voyager 1’s 11 instruments continue to return useful data, having now spent 10 years in interstellar space. Signals from the spacecraft take nearly 22 hours to reach Earth, and 22 hours for Earth-based signals to reach the spacecraft. Engineers expect that the spacecraft will continue to return data from interstellar space until about 2025 when it will no longer be able to power its systems. And just in case an alien intelligence finds it one day, Voyager 1 like its twin carries a gold-plated record that contains information about its home planet, including recordings of terrestrial sounds, music, and greetings in 55 languages. Engineers at NASA thoughtfully included Instructions on how to play the record.

The voyage continues…

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Emily Lakdawalla & Charlene Anderson • Feb 12, 2010

Twenty years since Voyager's last view

On Sunday comes the twentieth anniversary of an iconic image from the Voyager mission: the "Pale Blue Dot" photo of Earth caught in a sunbeam, which was captured by Voyager 1 as part of a Solar System Family Portrait. This panoramic view of our planetary cradle wouldn't have happened without years of advocacy by Planetary Society founder Carl Sagan, whose vision still inspires our organization.

Nothing like it has been done since. There hasn't been the opportunity -- Voyager 1 is the last spacecraft to have departed the solar system with a functional camera. The next one to be in a similar position will be New Horizons . I asked Alan Stern whether the Pluto-bound craft will take a family portrait from its distant perspective. He told me "Absolutely! But because of the bright Sun, we have to be careful for now, so we can't do it until after Pluto. We can however (and soon will-- this summer!) look back to Jupiter and see it and the Galilean satellites from 2+ billion km away near the orbit of Uranus. It should be quite evocative." Indeed it will.

There are several retrospectives on Voyager's solar system family portrait being posted across the Internet today, including this one from JPL and this really neat story from National Public Radio , featuring an interview of Candy Hansen, who was apparently the first person to spot Earth fixed in that sunbeam. Here's one written by the Society's Charlene Anderson a few years ago, on the occasion of the 25th anniversary of the Voyagers' launches.

by Charlene Anderson

This article is reprinted from the September/October 2002 issue of The Planetary Report.

Home. Family. This will be Voyager's enduring legacy: It has changed forever the feelings raised by those words. Through its robotic eyes we have learned to see the solar system as our home. Through its portraits of the planets we know that they are part of our family.

Apollo astronauts showed us a tiny Earth alone in the blackness of space. Now, with these images, Voyager has shown us that Earth is not really alone. Around our parent Sun orbit sibling worlds, companions as we travel through the Galaxy.

These family portraits of the Sun and planets were Voyager's final photographic assignment. Planetary Society President and Voyager Imaging Team member Carl Sagan worked for a decade to get these pictures taken. Between the two Voyager spacecraft, they returned some 67,000 images of the four outer planets and their 56 known moons. Voyager 1 had the slightly easier assignment: It encountered Jupiter in March 1979 and swung by Saturn in November 1980. Then it headed out in search of the heliopause, the edge of our Sun's sphere of magnetic influence, and where the solar wind gives way to the wind from the stars. In August 1989 Voyager 2 flew by Neptune, completing its reconnaissance mission, having visited Jupiter in 1979, Saturn in 1981 and Uranus in 1986. After passing Neptune, Voyager 2 joined its twin on the way to interstellar space.

The Voyagers had been launched in 1977 to take advantage of a planetary alignment that occurs only once every 176 years. The outer planets were lined up so that a spacecraft could swing from one to another, threading its way past the 4 gas giants in only 12 years. Mission planners at the Jet Propulsion Laboratory could select their paths from among many possible trajectories and targets.

For Voyager 1, they chose to send the spacecraft close by Titan's south pole to obtain close-up data on Saturn's largest moon. Titan's thick nitrogen atmosphere proved to be heavy with complex, carbon-rich organic molecules, and its surface is possibly dotted with lakes of liquid hydrocarbons. For carbon-based lifeforms living in a primarily nitrogen atmosphere - such as ourselves - a world like Titan is well worth a close look.

But to fly close to Titan, the project team had to sacrifice Voyager 1's encounters with Uranus and Neptune or a close-up look at Pluto. Its path around Saturn swung the spacecraft up and out of the ecliptic, the plane defined by Earth's orbit about the Sun. Looking from its Pasadena home on Earth's northern hemisphere, the spacecraft now appears to be coasting above our solar system.

Voyager 1 was chosen to take the family portrait because fewer instruments might be damaged by looking back toward the Sun. And, to Voyager 2, now beyond Neptune and traveling much closer to the ecliptic, Jupiter was too close to the Sun to be picked up by the spacecraft's cameras.

So on February 14 - Valentine's Day 1990 - Voyager 1 aimed its cameras at a string of small colored dots clustered just to the right of the constellation Orion - the Hunter. The spacecraft was then 32 degrees above the ecliptic and nearly 6 billion kilometers (3.7 billion miles) from the Sun. It took 39 wide-angle views and 21 narrow-angle images. The narrow-angle camera, with a lens resembling a telephoto, took three consecutive images through colored filters of seven of the nine planets. This enabled image processors at the Jet Propulsion Laboratory to construct the colored portraits of the planets seen on pages 16 and 17. The Multi-Mission Image Processing Laboratory then pasted together the wide-angle images into the mosaic on the next page.

Voyager had produced the first portrait ever of our Sun and planets together.

But like shy family members at a holiday gathering, the smallest planets avoided having their pictures taken. Mars and Mercury were lost in the glare of the Sun. The outermost planet, Pluto, was too tiny and far away. So this family portrait is incomplete. The next generation of spacecraft will be unable to take another family portrait. Magellan and Galileo, and the planned missions, such as the Soviets' Mars '94 and NASA's Mars Observer and Comet Rendezvous/Asteroid Flyby, plus the joint NASA/European Space Agency Cassini mission, will be locked in orbit about their target planets. None of these will ever gain a perspective from which they could see the solar system as Voyager did.

Voyager alone could look homeward and capture our family of planets as they looked on February 15, 1990. Voyager alone could so graphically show us how Earth and the planets are inextricably linked to our parent Sun.

Home is now a corner of space brightened by a small yellow star. Family is now a company of planets circling that star together. Our home and family now encompass an entire solar system.

Thank you, Voyager.

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To learn more about Voyager, zoom in and give the spacecraft a spin. View the full interactive experience at Eyes on the Solar System . Credit: NASA/JPL-Caltech

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April 22, 2024

After Months of Gibberish, Voyager 1 Is Communicating Well Again

NASA scientists spent months coaxing the 46-year-old Voyager 1 spacecraft back into healthy communication

By Meghan Bartels

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.

NASA/JPL-Caltech

After months of nonsensical transmissions from humanity’s most distant emissary, NASA’s iconic Voyager 1 spacecraft is finally communicating intelligibly with Earth again.

Voyager 1 launched in 1977 , zipped past Jupiter and Saturn within just a few years and has been trekking farther from our sun ever since; the craft crossed into interstellar space in 2012. But in mid-November 2023 Voyager 1’s data transmissions became garbled , sending NASA engineers on a slow quest to troubleshoot the distant spacecraft. Finally, that work has paid off, and NASA has clear information on the probe’s health and status, the agency announced on April 22.

“It’s the most serious issue we’ve had since I’ve been the project manager, and it’s scary because you lose communication with the spacecraft,” said Suzanne Dodd, Voyager project manager at NASA’s Jet Propulsion Laboratory in an interview with Scientific American when the team was still tracking down the issue.

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The Voyager 1 spacecraft is a scientific legend : It discovered that Jupiter’s moon Io, far from being a dead world like our own companion, is instead a supervolcanic world . The craft’s data suggested that Saturn’s moon Titan might have liquid on its surface. And for more than a decade, Voyager 1 has given scientists a glimpse at what space looks like beyond the influence of our sun.

Yet its long years in the harsh environment of space have done a number on the probe, which was designed to last just four years. In particular, degraded performance and low power supplies have forced NASA to turn off six of its 10 instruments, and its communication has gotten even spottier than can be explained by the fact that cosmic mechanics mean a signal takes nearly one Earth day to travel between humans and the probe.

When the latest communications glitch occurred last fall, scientists could still send signals to the distant probe, and they could tell that the spacecraft was operating. But all they got from Voyager 1 was gibberish—what NASA described in December 2023 as “a repeating pattern of ones and zeros.” The team was able to trace the issue back to a part of the spacecraft’s computer system called the flight data subsystem, or FDS, and identified that a particular chip within that system had failed.

Mission personnel couldn’t repair the chip. They were, however, able to break the code held on the failed chip into pieces they could tuck into spare corners of the FDS’s memory, according to NASA. The first such fix was transmitted to Voyager 1 on April 18. With a total distance of 30 billion miles to cross from Earth to the spacecraft and back, the team had to wait nearly two full days for a response from the probe. But on April 20 NASA got confirmation that the initial fix worked. Additional commands to rewrite the rest of the FDS system’s lost code are scheduled for the coming weeks, according to the space agency, including commands that will restore the spacecraft’s ability to send home science data.

Although, for now, Voyager 1 appears to be on the mend, NASA scientists know it won’t last forever. Sooner or later, a glitch they can’t fix will occur, or the spacecraft’s ever dwindling fuel supply will run out for good. Until then NASA is determined to get as much data as possible out of the venerable spacecraft—and its twin, Voyager 2, which experienced its own communications glitch earlier in 2023 .

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.

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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.

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Voyager 1 transmitting data again after Nasa remotely fixes 46-year-old probe

Engineers spent months working to repair link with Earth’s most distant spacecraft, says space agency

Earth’s most distant spacecraft, Voyager 1, has started communicating properly again with Nasa after engineers worked for months to remotely fix the 46-year-old probe.

Nasa’s Jet Propulsion Laboratory (JPL), which makes and operates the agency’s robotic spacecraft, said in December that the probe – more than 15bn miles (24bn kilometres) away – was sending gibberish code back to Earth.

In an update released on Monday , JPL announced the mission team had managed “after some inventive sleuthing” to receive usable data about the health and status of Voyager 1’s engineering systems. “The next step is to enable the spacecraft to begin returning science data again,” JPL said. Despite the fault, Voyager 1 had operated normally throughout, it added.

Launched in 1977, Voyager 1 was designed with the primary goal of conducting close-up studies of Jupiter and Saturn in a five-year mission. However, its journey continued and the spacecraft is now approaching a half-century in operation.

Voyager 1 crossed into interstellar space in August 2012, making it the first human-made object to venture out of the solar system. It is currently travelling at 37,800mph (60,821km/h).

Hi, it's me. - V1 https://t.co/jgGFBfxIOe — NASA Voyager (@NASAVoyager) April 22, 2024

The recent problem was related to one of the spacecraft’s three onboard computers, which are responsible for packaging the science and engineering data before it is sent to Earth. Unable to repair a broken chip, the JPL team decided to move the corrupted code elsewhere, a tricky job considering the old technology.

The computers on Voyager 1 and its sister probe, Voyager 2, have less than 70 kilobytes of memory in total – the equivalent of a low-resolution computer image. They use old-fashioned digital tape to record data.

The fix was transmitted from Earth on 18 April but it took two days to assess if it had been successful as a radio signal takes about 22 and a half hours to reach Voyager 1 and another 22 and a half hours for a response to come back to Earth. “When the mission flight team heard back from the spacecraft on 20 April, they saw that the modification worked,” JPL said.

Alongside its announcement, JPL posted a photo of members of the Voyager flight team cheering and clapping in a conference room after receiving usable data again, with laptops, notebooks and doughnuts on the table in front of them.

The Retired Canadian astronaut Chris Hadfield, who flew two space shuttle missions and acted as commander of the International Space Station, compared the JPL mission to long-distance maintenance on a vintage car.

“Imagine a computer chip fails in your 1977 vehicle. Now imagine it’s in interstellar space, 15bn miles away,” Hadfield wrote on X . “Nasa’s Voyager probe just got fixed by this team of brilliant software mechanics.

Voyager 1 and 2 have made numerous scientific discoveries , including taking detailed recordings of Saturn and revealing that Jupiter also has rings, as well as active volcanism on one of its moons, Io. The probes later discovered 23 new moons around the outer planets.

As their trajectory takes them so far from the sun, the Voyager probes are unable to use solar panels, instead converting the heat produced from the natural radioactive decay of plutonium into electricity to power the spacecraft’s systems.

Nasa hopes to continue to collect data from the two Voyager spacecraft for several more years but engineers expect the probes will be too far out of range to communicate in about a decade, depending on how much power they can generate. Voyager 2 is slightly behind its twin and is moving slightly slower.

In roughly 40,000 years, the probes will pass relatively close, in astronomical terms, to two stars. Voyager 1 will come within 1.7 light years of a star in the constellation Ursa Minor, while Voyager 2 will come within a similar distance of a star called Ross 248 in the constellation of Andromeda.

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Voyager 1 had a problem. Here's how NASA fixed it from 15 billion miles away.

Working from more than 15 billion miles away, NASA engineers have solved a computer problem aboard Voyager 1 , allowing the probe to send readable data five months after a chip error made its transmissions impossible to decipher.

Voyager 1, along with its sister craft, Voyager 2, are  robotic probes  that were launched in 1977. Voyager 1 reached interstellar space in 2012. It's now 15.1 billion miles away, the farthest from Earth a human-made object has ever traveled.

Learn more: Closer look at Voyager 1 and Voyager 2 .

Voyager 2 entered interstellar space − the space between the stars, starting at abou t 11 billion miles from our sun − in 2018. It's now 12.7 billion miles away.

Voyager 1's computer glitch garbled the science and engineering data the craft sends to Earth, which rendered it unreadable. That started on Nov. 14, 2023.

How did engineers fix Voyager's problem?

Engineers from NASA and the Jet Propulsion Laboratory discovered a single computer chip inside the spacecraft’s Flight Data Subsystem – which collects science and engineering information and transmits it to Earth – had malfunctioned.

Can't see our graphics? Click here .

The chip stored part of the Flight Data Subsystem's memory and software code. Engineers could still receive data from Voyager 1, but it was scrambled.

The chip could not be repaired. Instead, engineers moved software code from the chip into a different part of the subsystem's memory system.

The code was too large to to be stored in a single location in the spacecraft. Engineers divided the code into sections and stored them in different places within the subsystem. The code sections were adjusted to make sure they worked as a whole.

Engineers tested the fix by moving a code that transmits data about the spacecraft. They were rewarded with a transmission from Voyager that contained readable data about the craft's status.

All that took time. Voyager is moving about 38,000 mph. Because it's so far away, it takes 22.5 hours for a radio signal to reach Voyager. It takes another 22.5 hours for the spacecraft’s reply to reach antenna networks on Earth.

What happens next?

Engineers will reposition and synchronize the other parts of the code. That should allow Voyager 1 to start sending readable data on what it finds as it moves farther away from Earth.

SOURCE USA TODAY Network reporting and research; NASA/Jet Propulsion Laboratory/California Institute of Technology; Reuters

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

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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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