voyager 1 trip

Voyager 1 Trajectory through the Solar System

• Released Thursday, August 31, 2017
• Visualizations by:
• Tom Bridgman

This visualization tracks the trajectory of the Voyager 1 spacecraft through the solar system. Launched on September 5, 1977, it was one of two spacecraft sent to visit the giant planets of the outer solar system. Voyager 1 flew by Jupiter and Saturn before being directed out of the solar system. To fit the 40 year history of the mission into a short visualization, the pacing of time accelerates through most of the movie, starting at about 5 days per second at the beginning and speeding up to about 11 months per second after the planet flybys are past. The termination shock and heliopause are the 'boundaries' created when the plasma between the stars interacts with the plasma flowing outward from the Sun. They are represented with simple grid models and oriented so their 'nose' is pointed in the direction (Right Ascension = 17h 24m, declination = 17 degrees south) represented by more recent measurements from other missions.

Visualization centered on the Voyager 1 trajectory through the solar system.

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Voyager 1's 'Family Portrait' On Valentine's Day 1990, Voyager 1's camera were pointed back at the solar system to image the planets. Check out Voyager at NASA/JPL for more information.

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Opening view of Earth orbit looking outward to the rest of the solar system.

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Voyager 1 (and 2) cross the orbit of Mars, slightly above the ecliptic plane to avoid the asteroid belt between Mars & Jupiter.

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The camera moves out ahead of the Voyagers for a view back at the inner solar system.

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Voyager 1 just after the Jupiter flyby on March 5, 1979.

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Voyager 1 just before the Saturn flyby on November 12, 1980.

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With a gravity-assist from the Saturn flyby, Voyager 1 is directed above the plane of the solar system and continues outward. This is near the time of the Voyager 1 'Family Portrait'. The orbit of Pluto is the grey orbit visible above the orbits of the other planets.

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Voyager 1 crosses the termination shock of the solar wind. For simplified and symmetric termination shock model, the timing is not accurate. In reality, this crossing occurred around December of 2004.

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Voyager 1 (and 2) beyond the heliopause near the end of 2017.

A slightly sped-up version of the Voyager 1 visualization above, reducing the time for the Voyagers to cross the asteroid belt.

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• Solar System

Please give credit for this item to: NASA's Scientific Visualization Studio

• Tom Bridgman  (Global Science and Technology, Inc.)
• Kathalina Tran  (KBR Wyle Services, LLC)
• Genna Duberstein  (USRA)
• Scott Wiessinger  (USRA)

Project support

• Laurence Schuler  (ADNET Systems, Inc.)
• Ian Jones  (ADNET Systems, Inc.)

Release date

This page was originally published on Thursday, August 31, 2017. This page was last updated on Wednesday, November 15, 2023 at 12:05 AM EST.

• Voyager @ 40
• Voyager Retrospective

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Hubble’s Brand New Image of Jupiter

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Voyager 1 Ephemeris Calculator

Compute the position of Voyager 1 for any date and time between 1 January 2013 and 30 December 2099 and display the results on an interactive star map.

Voyager 1 is a space probe launched by NASA on September 5, 1977, to study the outer Solar System and beyond. It is currently the most distant human-made object from Earth, having traveled over 14 billion miles (23 billion kilometers) from the Sun. Voyager 1's mission has included flybys of Jupiter and Saturn, with the goal of studying their moons, rings, and magnetic fields. The probe is now traveling through the heliosheath , the outermost layer of the Sun's heliosphere, and is expected to enter interstellar space in the coming years. Voyager 1 carries a golden record that contains sounds and images selected to portray the diversity of life and culture on Earth, in the event that it is ever encountered by extraterrestrial life.

Voyager 1 is currently in the constellation of Ophiucus , at a distance of 24,328,539,484 kilometers from Earth.

Today's rise, transit and set times of Voyager 1 from Greenwich, United Kingdom edit_location_alt (all times relative to the local timezone Europe/London):

• Voyager 1 is above the horizon from Greenwich, United Kingdom edit_location_alt .
• Right now it is placed in the East direction at an altitude of 12° above the horizon.
• Go to interactive sky chart

If you need to access this information frequently for your observations, you can create a simple customized Quick Access page , so that you can easily bookmark it in your browser favorites or add a shortcut to your mobile phones' home screen.

• Position and finder charts (see also Where is Voyager 1? )
• Distance from Earth (see also How far is Voyager 1 from Earth? )
• When does Voyager 1 rise and set?
• Interactive orbit visualization . 3d visualization showing the orbit of Voyager 1 with respect to the major Solar System objects.
• 15 days ephemerides . Table showing celestial coordinates and magnitude of Voyager 1 for the past and next 7 days.
• Interactive sky chart . An online planetarium application that shows where to locate Voyager 1 in the sky from your location.
• Live position tracker . A high precision sky chart that uses real deep sky imagery to help locate Voyager 1 with your telescope or on your astrophotographies.

Voyager 1 Position and Finder Charts

Higher precision deep sky finder chart, 60 arcmin wide, showing where Voyager 1 is right now. Click on the image to see a more detailed fullscreen tracker view .

Also check out Where is Voyager 1? , a page that provides all the information needed to find Voyager 1 in the sky and additional links to sky charts.

Voyager 1 Distance from Earth

The distance of Voyager 1 from Earth is currently 24,328,539,484 kilometers, equivalent to 162.626242 Astronomical Units . Light takes 22 hours, 32 minutes and 31.2726 seconds to travel from Voyager 1 and arrive to us.

The following chart shows the distance of Voyager 1 from Earth as a function of time. In the chart the distance data is measured in Astronomical Units and sampled with an interval of 1 day.

Closest Approach of Voyager 1 to Earth

NOTE: values for the closest approach are computed with a sampling interval of 1 day.

Visualization of Voyager 1 Orbit

This 3d orbit diagram is a feature of our 3D Solar System Simulator and shows the orbit of Voyager 1 with respect of the Sun and the orbits of the major planets . The position of Voyager 1 and the planets along their orbits in this diagram accurately represents the current configuration of the objects in the Solar System. This is an experimental feature and it requires a WebGL enabled browser. Please provide us feedback !

Voyager 1 15 Days Ephemeris

The following table lists the ephemerides of Voyager 1 computed for the past and next 7 days, with a 24 hours interval. Click on each row of the table to locate Voyager 1 in our Online Planetarium at the chosen date.

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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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Voyager 1: Facts about Earth's farthest spacecraft

Voyager 1 continues to explore the cosmos along with its twin probe, Voyager 2.

The Grand Tour

Voyager 1 jupiter flyby, voyager 1 visits saturn and its moons, voyager 1 enters interstellar space, voyager 1's interstellar adventures, additional resources.

Voyager 1 is the first spacecraft to travel beyond the solar system and reach interstellar space . 

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

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

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

Elizabeth Howell, Ph.D., is a staff writer in the spaceflight channel since 2022. She was contributing writer for  Space.com  for 10 years before that, since 2012. Elizabeth's on-site reporting includes two human spaceflight launches from Kazakhstan, three space shuttle missions in Florida, and embedded reporting from a simulated Mars mission in Utah. 

Size: Voyager 1's body is about the size of a subcompact car. The boom for its magnetometer instrument extends 42.7 feet (13 meters). Weight (at launch): 1,797 pounds (815 kilograms). Launch date: Sept. 5, 1977

Jupiter flyby date: March 5, 1979

Saturn flyby date: Nov. 12, 1980.

Entered interstellar space: Aug. 25, 2012. 

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

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

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

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

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

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

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

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

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

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

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

According to NASA , each voyager probe has about 3 million times less memory than a mobile phone and transmits data approximately 38,000 times slower than a 5g internet connection.  

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Bibliography

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

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Elizabeth Howell (she/her), Ph.D., is a staff writer in the spaceflight channel since 2022 covering diversity, education and gaming as well. She was contributing writer for Space.com for 10 years before joining full-time. Elizabeth's reporting includes multiple exclusives with the White House and Office of the Vice-President of the United States, an exclusive conversation with aspiring space tourist (and NSYNC bassist) Lance Bass, speaking several times with the International Space Station, witnessing five human spaceflight launches on two continents, flying parabolic, working inside a spacesuit, and participating in a simulated Mars mission. Her latest book, " Why Am I Taller ?", is co-written with astronaut Dave Williams. Elizabeth holds a Ph.D. and M.Sc. in Space Studies from the University of North Dakota, a Bachelor of Journalism from Canada's Carleton University and a Bachelor of History from Canada's Athabasca University. Elizabeth is also a post-secondary instructor in communications and science at several institutions since 2015; her experience includes developing and teaching an astronomy course at Canada's Algonquin College (with Indigenous content as well) to more than 1,000 students since 2020. Elizabeth first got interested in space after watching the movie Apollo 13 in 1996, and still wants to be an astronaut someday. Mastodon: https://qoto.org/@howellspace

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Voyager, NASA’s Longest-Lived Mission, Logs 45 Years in Space

This archival image taken at NASA’s Jet Propulsion Laboratory on March 23, 1977, shows engineers preparing the Voyager 2 spacecraft ahead of its launch later that year.

Launched in 1977, the twin Voyager probes are NASA’s longest-operating mission and the only spacecraft ever to explore interstellar space.

NASA’s twin Voyager probes have become, in some ways, time capsules of their era: They each carry an eight-track tape player for recording data, they have about 3 million times less memory than modern cellphones, and they transmit data about 38,000 times slower than a 5G internet connection.

Yet the Voyagers remain on the cutting edge of space exploration. Managed and operated by NASA’s Jet Propulsion Laboratory in Southern California, they are the only probes to ever explore interstellar space – the galactic ocean that our Sun and its planets travel through.

The Sun and the planets reside in the heliosphere, a protective bubble created by the Sun’s magnetic field and the outward flow of solar wind (charged particles from the Sun). Researchers – some of them younger than the two distant spacecraft – are combining Voyager’s observations with data from newer missions to get a more complete picture of our Sun and how the heliosphere interacts with interstellar space.

NASA’s Solar System Interactive lets users see where the Voyagers are right now relative to the planets, the Sun, and other spacecraft. View it yourself here . Credit: NASA/JPL-Caltech

“The heliophysics mission fleet provides invaluable insights into our Sun, from understanding the corona or the outermost part of the Sun’s atmosphere, to examining the Sun’s impacts throughout the solar system, including here on Earth, in our atmosphere, and on into interstellar space,” said Nicola Fox, director of the Heliophysics Division at NASA Headquarters in Washington. “Over the last 45 years, the Voyager missions have been integral in providing this knowledge and have helped change our understanding of the Sun and its influence in ways no other spacecraft can.”

The Voyagers are also ambassadors, each carrying a golden record containing images of life on Earth, diagrams of basic scientific principles, and audio that includes sounds from nature, greetings in multiple languages, and music. The gold-coated records serve as a cosmic “message in a bottle” for anyone who might encounter the space probes. At the rate gold decays in space and is eroded by cosmic radiation, the records will last more than a billion years.

45 Years of Voyager I and II

Launched in 1977, NASA’s twin Voyager spacecraft inspired the world with pioneering visits to Jupiter, Saturn, Uranus, and Neptune. Their journey continues 45 years later as both probes explore interstellar space, the region outside the protective heliosphere created by our Sun. Researchers – some younger than the spacecraft – are now using Voyager data to solve mysteries of our solar system and beyond.

This archival photo shows engineers working on vibration acoustics and pyro shock testing of NASA’s Voyager on Nov. 18, 1976. Credit: NASA/JPL-Caltech

NASA’s Voyager 1 acquired this image of a volcanic explosion on Io on March 4, 1979, about 11 hours before the spacecraft’s closest approach to the moon of Jupiter.

Neptune’s green-blue atmosphere was shown in greater detail than ever before in this image from NASA’s Voyager 2 as the spacecraft rapidly approached its encounter with the giant planet in August 1989.

This updated version of the iconic "Pale Blue Dot" image taken by the Voyager 1 spacecraft uses modern image-processing software and techniques to revisit the well-known Voyager view while attempting to respect the original data and intent of those who planned the images.

This illustrated graphic was made to mark Voyager 1’s entry into interstellar space in 2012. It puts solar system distances in perspective, with the scale bar in astronomical units and each set distance beyond 1 AU (the average distance between the Sun and Earth) representing 10 times the previous distance.

This graphic highlights some of the Voyager mission’s key accomplishments. Credit: NASA/JPL-Caltech Full image details

This graphic provides some of the mission’s key statistics from 2018, when NASA’s Voyager 2 probe exited the heliosphere. Credit: NASA/JPL-Caltech Full image details

Beyond Expectations

Voyager 2 launched on Aug. 20, 1977, quickly followed by Voyager 1 on Sept. 5. Both probes traveled to Jupiter and Saturn, with Voyager 1 moving faster and reaching them first. Together, the probes unveiled much about the solar system’s two largest planets and their moons. Voyager 2 also became the first and only spacecraft to fly close to Uranus (in 1986) and Neptune (in 1989), offering humanity remarkable views of – and insights into – these distant worlds.

While Voyager 2 was conducting these flybys, Voyager 1 headed toward the boundary of the heliosphere. Upon exiting it in 2012 , Voyager 1 discovered that the heliosphere blocks 70% of cosmic rays, or energetic particles created by exploding stars. Voyager 2, after completing its planetary explorations, continued to the heliosphere boundary, exiting in 2018 . The twin spacecraft’s combined data from this region has challenged previous theories about the exact shape of the heliosphere.

Voyager 1 and 2 have accomplished a lot since they launched in 1977. This infographic highlights the mission’s major milestones, including visiting the four outer planets and exiting the heliosphere, or the protective bubble of magnetic fields and particles created by the Sun.

“Today, as both Voyagers explore interstellar space, they are providing humanity with observations of uncharted territory,” said Linda Spilker, Voyager’s deputy project scientist at JPL. “This is the first time we’ve been able to directly study how a star, our Sun, interacts with the particles and magnetic fields outside our heliosphere, helping scientists understand the local neighborhood between the stars, upending some of the theories about this region, and providing key information for future missions.”

The Long Journey

Over the years, the Voyager team has grown accustomed to surmounting challenges that come with operating such mature spacecraft, sometimes calling upon retired colleagues for their expertise or digging through documents written decades ago.

Each Voyager is powered by a radioisotope thermoelectric generator containing plutonium, which gives off heat that is converted to electricity. As the plutonium decays, the heat output decreases and the Voyagers lose electricity. To compensate , the team turned off all nonessential systems and some once considered essential, including heaters that protect the still-operating instruments from the frigid temperatures of space. All five of the instruments that have had their heaters turned off since 2019 are still working, despite being well below the lowest temperatures they were ever tested at.

Get the Latest JPL News

Recently, Voyager 1 began experiencing an issue that caused status information about one of its onboard systems to become garbled. Despite this, the system and spacecraft otherwise continue to operate normally, suggesting the problem is with the production of the status data, not the system itself. The probe is still sending back science observations while the engineering team tries to fix the problem or find a way to work around it.

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

More About the Mission

A division of Caltech in Pasadena, JPL built and operates the Voyager spacecraft. The Voyager missions are a part of the NASA Heliophysics System Observatory, sponsored by the Heliophysics Division of the Science Mission Directorate in Washington.

For more information about the Voyager spacecraft, visit:

https://www.nasa.gov/voyager

News Media Contact

Calla Cofield

Jet Propulsion Laboratory, Pasadena, Calif.

626-808-2469

[email protected]

March 14, 2024

10 min read

Voyager 1’s Immortal Interstellar Requiem

NASA is reaching across more than 15 billion miles to rescue its malfunctioning Voyager 1 probe—but this hallowed interstellar mission can’t live forever

By Nadia Drake

An artist's concept of NASA's Voyager 1, the space agency's venerable and farthest-flung interplanetary probe.

Mark Garlick/Science Photo Library

In the fall of last year, one of NASA’s most venerable spacecraft started beaming home nonsense. Its usual string of 1’s and 0’s—binary code that collectively told of its journey into the unknown—became suddenly unintelligible.

Some 15 billion miles from Earth, beyond the protective bubble blown by the sun and in interstellar space, Voyager 1 was in trouble.

“We’d gone from having a conversation with Voyager, with the 1’s and 0’s containing science data, to just a dial tone,” says Linda Spilker , Voyager project scientist at NASA’s Jet Propulsion Laboratory (JPL).

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Spilker joined JPL in 1977, the same year that NASA launched Voyager 1 and its twin, Voyager 2 , on what, in a way, was an endless odyssey: from Earth, to the outer solar system and ultimately to interstellar infinity . Today there are several billion people on Earth who have never taken a breath without the Voyagers in our sky, people who, like me, have only ever existed in a cosmos shared with these talkative twin spacecraft. But like people, spacecraft get old. They break down .

And all good things—and even great ones—must come to an end. After days, and weeks and then months of nothing but indecipherable binary babbling, Voyager 1’s earthbound stewards had to reckon with the idea that maybe, after more than 46 years, its time had at last run out.

The Voyager 1 team at JPL had traced the problem to the spacecraft’s Flight Data System, an onboard computer that parses and parcels engineering and science measurements for subsequent radio transmittal to Earth. One possibility was that a high-energy cosmic particle had struck Voyager 1 and caused a bit flip within the system’s memory — something that has happened more frequently as the craft navigates the hostile wilds of interstellar space. Normally, the team would simply ask the spacecraft for a memory readout, allowing its members to find and reset the errant bit.

“We’ve recovered from bit flips before. The problem this time is we don’t know where the bit flip is because we can’t see what the memory is,” says Suzanne Dodd , Voyager project manager at JPL, who, like Spilker, began her long career with work on the probes. “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.”

Yesterday, the team announced a significant step in breaking through to Voyager 1. After months of stress and unsuccessful answers they have managed to decode at least a portion of the spacecraft’s gobbledygook, allowing them to (maybe) find a way to see what it has been trying to say.

“It’s an excellent development on Voyager,” says Joe Westlake , director of NASA’s heliophysics division, which oversees the mission.

In the time it will take you to read this story, Voyager 1 will have traversed approximately 10,000 miles of mostly empty space ; in the weeks it took me to report it, the probe traveled some 26 million miles. And since its communication first became garbled last November, the spacecraft has sailed another 10 light-minutes away from home. Voyager 1 and its twin are slipping away from us as surely as the passage of time itself. Sooner or later, these hallowed space-age icons will fall silent, becoming no more than distant memories.

And even among the space community, which of course loves all of its robotic explorers equally, the Voyagers are special. “They are incredibly important and much beloved spacecraft,” says Nicola Fox , NASA’s associate administrator for science. “Voyager 1 is a national treasure, along with Voyager 2 .”

As envisioned, the Voyager mission would exploit a once-in-175-year alignment of Jupiter, Saturn, Uranus and Neptune to slingshot through the solar system’s sparsely charted hinterlands. Legend has it that NASA’s administrator sold the project to President Richard Nixon by noting that the last time the planets were so favorably arranged, Thomas Jefferson was living in the White House. Outfitted with nuclear power sources, the Voyagers were built to last—in utter defiance of the adage that what must go up, must come down. Neither was ever intended to make planetfall again; instead they were bound for the stars. And now, nearly a half-century later, the pair have become the longest-lived and farthest-flung probes ever dispatched by humankind. (Voyager 1 is the front-runner, with its sibling trailing close behind.)

Spilker was straight out of college when she started working on the Voyagers, eager to see the outer solar system through their robotic eyes as they surfed the rare celestial alignment. “I had a telescope in third grade that I used to look at Jupiter and Saturn,” she says. “I wanted to get up really close and get a look at what these planets look like.”

Between 1979 and 1981, Voyager 1 and Voyager 2 zipped by the gas giants , returning stunning images of banded Jupiter and buttery Saturn and their bewildering collection of moons. Voyager 2 went on to scrutinize the ice giants: Uranus in 1986 and Neptune in 1989. These were the first and only times anyone had seen each of these bluish ringed worlds up close.

“They were small little pinpoints of light, and now you’re flying close,” Spilker says. “And you see the cliffs of Miranda”—a bizarre Uranian moon—“and Triton, with active geysers going off.” (Nobody had expected to see an active icy world in orbit around Neptune, and even now Voyager’s 35-year-old image is still the best we have of that strange little moon.)

When the Voyagers left the realm of the known planets, each followed a different path into darkness: Voyager 1 arced up and out of the plane of the solar system, and Voyager 2 looped downward. Spilker also followed her own path: she went to graduate school and earned her doctorate in planetary science using Voyager data—not knowing that several decades later, after leading NASA’s Cassini mission to Saturn, she’d again be part of the mission that started it all.

“The chance came to go back to Voyager,” she says. “And I said, ‘Of course. I’d love to go back.’”

In the interim, as the Voyagers sailed farther from their Earthly harbor, teams shut down many of the onboard instruments, including the cameras. But the pair kept studying the space that they alone were visiting. Their main job was now to characterize the heliosphere—the solar-system-encompassing, cosmic-ray-blocking bubble formed by our sun’s wind and magnetic field. They would document the alien mix of particles and fields that pervade near nothingness. And maybe, if they got lucky, the twins would each escape the protective solar caul entirely to be reborn as true interstellar wanderers.

In 2012 Voyager 1 transcended this boundary , known as the heliopause, where the sun’s influence wanes. Before that scientists could only guess at what lay beyond this barrier and could only model how it shielded Earth from the harshness of the void. Now Voyager 1 could tell us directly about the stuff between the stars. Voyager 2 followed in 2018 , and Fox—then the new chief of NASA’s heliophysics division—was in the midst of the action.

“You’re looking at the cosmic rays going up and the solar wind going down, and it was one of those ‘oh, my god, this is so exciting’ moments,” Fox recalls. “I think of the Voyagers as one mission,” she says. “We’re putting all the data together, but they’re the ones that are out there. They’re the brave spacecraft that have left the protective bubble of the heliosphere and are out exploring interstellar space. It’s hard not to be excited by them.”

This wasn’t the first time Voyager 1 had started speaking an unintelligible language. In 2022, when the probe suffered an earlier bout of garbled telemetry, JPL engineer Bob Rasmussen was shaken out of retirement. The lab wanted to know if Rasmussen, who’d joined the spacecraft’s systems engineering team in 1975, was willing to have a think about the situation.

“I’d been happily retired for a bit more than a year at that point, with plenty else to keep me busy,” Rasmussen says. “But I like solving puzzles, and this was a tough one that I just couldn’t pass up. Cracking it took a few months, but the puzzle stream hasn’t slowed since then.”

Afterward, he stayed on-call. So last November, when Voyager 1 again started transmitting nonsense, Rasmussen was ready for more problem-solving. He was joined by a hand-picked team of specialists, and together they dove into the details for getting the ailing spacecraft back in action.

The problems were at least three layers deep. First, it takes a long time to communicate with Voyager 1. Traveling at the speed of light, the radio signals used to command the spacecraft take 22.5 hours to travel 15 billion miles—and 22.5 hours to come back. Second, the Voyagers are not exactly modern technology.

“Most things don’t last 46 years. Your clock radio and toaster aren’t going to last 46 years,” says Dodd, who started on the Voyager project straight out of school, then worked on other missions and is now back on this one.

Plus, many of the people who built and developed the spacecraft in the 1970s aren’t around to explain the rationale behind the designs.

And third, unluckily enough, whatever had mangled the spacecraft had managed to take out Voyager 1’s ability to send meaningful communications. The team was in the dark, trying to find the invisible source of an error. (Imagine trying to revive a stalled desktop computer with a frozen screen: you can’t see your cursor, and your clicks risk causing more problems—except in this case each input carries a multiday lag and could damage a precious, misbehaving artifact that is more than 15 billion miles away.) Perhaps the most vexing part was the team’s knowledge that Voyager 1 was otherwise intact and functioning as it should be.

“It’s still doing what it’s supposed to be doing,” Westlake says. “It just can’t quite figure out how to send the correct message home.”

Rasmussen and his colleagues set out to understand the spacecraft in as much detail as possible. That meant poring over the original design schematics, now yellowed and pinned to various walls—an effort that resembled “a bit of an archaeology dig,” Dodd says—and studying how past teams had addressed anomalies. That was tricky, Dodd says, because even though the team members could figure out how engineers solved a problem, they couldn’t necessarily discern the rationale behind various solutions. They’d send commands to Voyager 1 about once a week—usually on Fridays—and by Sunday, they’d hear back from the spacecraft.

“There’s suspense after each cautious move, hope with each piece that falls into place, disappointment if our hunches are wrong,” Rasmussen says.

Progress was slow. And as time crept on, the team grew more concerned. But no one was giving up, at any level of leadership.

“I will rely on the Voyager team to say, ‘Hey, Nicky, we’ve done everything , ’” Fox says. “We wouldn’t make any decisions until we knew that every single thing had been tried and tried again because we really do want to get Voyager 1 back talking to us.”

And then, in early March, something changed. In response to a command, instead of beaming back absolute gibberish, the spacecraft sent a string of numbers that looked more familiar. It proved to be a Rosetta stone moment. Soon an unnamed engineer at NASA’s Deep Space Network—the globe-girdling array of radio dishes that relays information from Earth to spacecraft—had learned how to speak Voyager 1’s jumbled language.

After translating that vaguely familiar portion of the spacecraft’s transmission, the team could see that it contained a readout of the flight data system’s memory. Now they face new questions: Can they find and correct the source of the mutated code? Can they learn whether the spacecraft is sending useful science data? Can they restore Voyager 1’s lexicon to its original state—or will they need to continue speaking in the probe’s new postheliopause patois? “The hope is that we’ll get good science data back,” Westlake says. “Thinking about something that’s been a constant throughout my entire career going away is really tough to think about.”

But either by glitch or time’s slow decay of radioactive power sources, the Voyagers will, of course, eventually fade away. Each year they lose four watts of power, and they grow ever colder. “Whether it’s this particular anomaly that gets us or one downstream, or the spacecraft gets old enough and cold enough —one day you’ll go to look for it and it has just stopped working,” Spilker says.

Like silent ambassadors or wordless emissaries, the Voyagers will keep sailing outward, still carrying us with them into the stars—“sort of like a message a bottle,” Spilker says.

Besides their science payloads, a fraction of each spacecraft’s mass was devoted to casting a cosmic message into the interstellar ocean from a lonely island called Earth. Mounted to each probe is a golden record etched with grooves encoding a selection of sights and sounds from our small corner of space and time. An accompanying stylus is positioned to play the record from the beginning, alongside a pictographic and arithmetic instruction manual.

The records are gold because gold is stable for eons, and they’re records because that was the best way to store a lot of information in the 1970s. Should they ever be recovered and decoded, the message will tell the stories of we humans—at least as envisioned (and in some cases performed) by a small group of folks that included my parents ( the late astrophysicist Frank Drake and his surviving spouse Amahl Shakhashiri Drake), astronomer Carl Sagan, documentary producer Ann Druyan and science writer Timothy Ferris. Those stories are imperfect. They’re filled with lopsided optimism and scrubbed of references to war, famine, poverty and most any other Earthly failing—a deliberate decision to hide the defects of our broken world. I know this because my dad, the record’s technical director and a pioneer in the scientific quest to find cosmic civilizations, told me about the hard choices he’d made in selecting the photographs. And I know it because my mom, who recorded the message’s Arabic greeting (“Greetings to our friends in the stars. We wish that we will meet you someday”), helped, too.

For me, as the Voyagers travel through space , they’re not only helping us understand the cosmic context in which we exist; they’re also bearing a memento of my parents into the stars. These spacecraft—and their gleaming paean to Earth—will survive for billions of years. Long after our world, our sun and everything we hold dear becomes unrecognizable, the Voyagers will remain, resolutely speeding ever farther from a home that no longer exists and containing artifacts of a civilization that once was.

That’s why, over nearly half a century, the Voyagers and their interstellar tidings have come to be bigger than the already audacious mission they were designed to accomplish. Their reach is broader. And their inevitable silence will be profound.

“The thought that they’re out there on their own and you can no longer communicate with them—it’s traumatic,” Fox says. “It’s sad. It’s really sad.”

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Voyager 1’s mission to the outer planet begins.

The Voyager mission was designed to take advantage of a rare geometric arrangement of the outer planets in the late 1970s and the 1980s which allowed for a four-planet tour with a minimum of propellant and trip time. This layout of Jupiter, Saturn, Uranus and Neptune, which occurs about every 175 years, allows a spacecraft on a particular flight path to swing from one planet to the next without the need for large onboard propulsion systems.

NASA’s Voyager 1 spacecraft launched after Voyager 2, on a faster, shorter trajectory. This image captures that moment in Cape Canaveral, Florida on Sept. 5, 1977.

Image credit: NASA/JPL-Caltech/KSC

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Voyager 1, First Craft in Interstellar Space, May Have Gone Dark

The 46-year-old probe, which flew by Jupiter and Saturn in its youth and inspired earthlings with images of the planet as a “Pale Blue Dot,” hasn’t sent usable data from interstellar space in months.

By Orlando Mayorquin

When Voyager 1 launched in 1977, scientists hoped it could do what it was built to do and take up-close images of Jupiter and Saturn. It did that — and much more.

Voyager 1 discovered active volcanoes, moons and planetary rings, proving along the way that Earth and all of humanity could be squished into a single pixel in a photograph, a “ pale blue dot, ” as the astronomer Carl Sagan called it. It stretched a four-year mission into the present day, embarking on the deepest journey ever into space.

Now, it may have bid its final farewell to that faraway dot.

Voyager 1 , the farthest man-made object in space, hasn’t sent coherent data to Earth since November. NASA has been trying to diagnose what the Voyager mission’s project manager, Suzanne Dodd, called the “most serious issue” the robotic probe has faced since she took the job in 2010.

The spacecraft encountered a glitch in one of its computers that has eliminated its ability to send engineering and science data back to Earth.

The loss of Voyager 1 would cap decades of scientific breakthroughs and signal the beginning of the end for a mission that has given shape to humanity’s most distant ambition and inspired generations to look to the skies.

“Scientifically, it’s a big loss,” Ms. Dodd said. “I think — emotionally — it’s maybe even a bigger loss.”

Voyager 1 is one half of the Voyager mission. It has a twin spacecraft, Voyager 2.

Launched in 1977, they were primarily built for a four-year trip to Jupiter and Saturn , expanding on earlier flybys by the Pioneer 10 and 11 probes.

The Voyager mission capitalized on a rare alignment of the outer planets — once every 175 years — allowing the probes to visit all four.

Using the gravity of each planet, the Voyager spacecraft could swing onto the next, according to NASA .

The mission to Jupiter and Saturn was a success.

The 1980s flybys yielded several new discoveries, including new insights about the so-called great red spot on Jupiter, the rings around Saturn and the many moons of each planet.

Voyager 2 also explored Uranus and Neptune , becoming in 1989 the only spacecraft to explore all four outer planets.

Voyager 1, meanwhile, had set a course for deep space, using its camera to photograph the planets it was leaving behind along the way. Voyager 2 would later begin its own trek into deep space.

“Anybody who is interested in space is interested in the things Voyager discovered about the outer planets and their moons,” said Kate Howells, the public education specialist at the Planetary Society, an organization co-founded by Dr. Sagan to promote space exploration.

“But I think the pale blue dot was one of those things that was sort of more poetic and touching,” she added.

On Valentine’s Day 1990, Voyager 1, darting 3.7 billion miles away from the sun toward the outer reaches of the solar system, turned around and snapped a photo of Earth that Dr. Sagan and others understood to be a humbling self-portrait of humanity.

“It’s known the world over, and it does connect humanity to the stars,” Ms. Dodd said of the mission.

She added: “I’ve had many, many many people come up to me and say: ‘Wow, I love Voyager. It’s what got me excited about space. It’s what got me thinking about our place here on Earth and what that means.’”

Ms. Howells, 35, counts herself among those people.

About 10 years ago, to celebrate the beginning of her space career, Ms. Howells spent her first paycheck from the Planetary Society to get a Voyager tattoo.

Though spacecraft “all kind of look the same,” she said, more people recognize the tattoo than she anticipated.

“I think that speaks to how famous Voyager is,” she said.

The Voyagers made their mark on popular culture , inspiring a highly intelligent “Voyager 6” in “Star Trek: The Motion Picture” and references on “The X Files” and “The West Wing.”

Even as more advanced probes were launched from Earth, Voyager 1 continued to reliably enrich our understanding of space.

In 2012, it became the first man-made object to exit the heliosphere, the space around the solar system directly influenced by the sun. There is a technical debate among scientists around whether Voyager 1 has actually left the solar system, but, nonetheless, it became interstellar — traversing the space between stars.

That charted a new path for heliophysics, which looks at how the sun influences the space around it. In 2018, Voyager 2 followed its twin between the stars.

Before Voyager 1, scientific data on the sun’s gases and material came only from within the heliosphere’s confines, according to Dr. Jamie Rankin, Voyager’s deputy project scientist.

“And so now we can for the first time kind of connect the inside-out view from the outside-in,” Dr. Rankin said, “That’s a big part of it,” she added. “But the other half is simply that a lot of this material can’t be measured any other way than sending a spacecraft out there.”

Voyager 1 and 2 are the only such spacecraft. Before it went offline, Voyager 1 had been studying an anomalous disturbance in the magnetic field and plasma particles in interstellar space.

“Nothing else is getting launched to go out there,” Ms. Dodd said. “So that’s why we’re spending the time and being careful about trying to recover this spacecraft — because the science is so valuable.”

But recovery means getting under the hood of an aging spacecraft more than 15 billion miles away, equipped with the technology of yesteryear. It takes 45 hours to exchange information with the craft.

It has been repeated over the years that a smartphone has hundreds of thousands of times Voyager 1’s memory — and that the radio transmitter emits as many watts as a refrigerator lightbulb.

“There was one analogy given that is it’s like trying to figure out where your cursor is on your laptop screen when your laptop screen doesn’t work,” Ms. Dodd said.

Her team is still holding out hope, she said, especially as the tantalizing 50th launch anniversary in 2027 approaches. Voyager 1 has survived glitches before, though none as serious.

Voyager 2 is still operational, but aging. It has faced its own technical difficulties too.

NASA had already estimated that the nuclear-powered generators of both spacecrafts would likely die around 2025.

Even if the Voyager interstellar mission is near its end, the voyage still has far to go.

Voyager 1 and its twin, each 40,000 years away from the next closest star, will arguably remain on an indefinite mission.

“If Voyager should sometime in its distant future encounter beings from some other civilization in space, it bears a message,” Dr. Sagan said in a 1980 interview .

Each spacecraft carries a gold-plated phonograph record loaded with an array of sound recordings and images representing humanity’s richness, its diverse cultures and life on Earth.

“A gift across the cosmic ocean from one island of civilization to another,” Dr. Sagan said.

Orlando Mayorquin is a general assignment and breaking news reporter based in New York. More about Orlando Mayorquin

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NASA's Voyager 1 resumes sending engineering updates to Earth

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.

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 affected the 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 22.5 hours to reach Voyager 1, which is over 15 billion miles (24 billion kilometers) from Earth, and another 22.5 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 had worked: For the first time in five months, they have been able to check the health and status of the spacecraft.

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.

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• The Inventory

NASA's Voyager 1 Is Finally Making Sense After Months of Transmitting Gibberish

Jpl engineers pinpointed the cause behind the anomaly and came up with a clever plan to rescue the iconic mission..

The Voyager 1 spacecraft returned usable data for the first time in more than five months, giving hope for the 46-year-old mission to finally be able to resume its normal operations.

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NASA’s favorite interstellar probe transmitted data about the health and status of its onboard engineering systems to mission control on Saturday, the space agency announced . That’s great news for the mission, and the next step is hopefully for Voyager 1 to begin returning science data again.

The last time Voyager 1 sent readable science and engineering data back to Earth was on November 14, 2023. Afterwards, the spacecraft was receiving commands, but talking back to Earth in unusable gibberish . The storied spacecraft is exploring the outermost edge of the Sun’s domain, combining its observations with data from newer missions to get a better understanding of how the heliosphere interacts with interstellar space.

Related article: Voyager Probes Spot Previously Unknown Phenomenon in Deep Space

In March, the team at NASA’s Jet Propulsion Lab (JPL) pinpointed the cause behind Voyager 1's nonsensical data : a single chip responsible for storing part of the affected portion of the spacecraft’s flight data system (FDS) memory.

FDS collects data from Voyager’s science instruments, as well as engineering data about the health of the spacecraft, and combines them into a single package that’s transmitted to Earth in binary code. Since the glitch, however, the mission has been sending data in a repeating pattern of ones and zeroes.

Voyager 1 is 15.14 billion miles away, which makes repairing it that much more complicated. The engineers at JPL knew that they couldn’t fix the chip, but they could try to place the affected code elsewhere in the FDS memory.

Instead of selecting a single location to hold all of the affected code, the team came up with a plan to divide it into sections and store those sections in different places in the FDS. On April 18, the mission team singled out the code responsible for packaging the spacecraft’s engineering data and sent it to its new location.

Two days later, the engineers heard back from the Voyager 1 spacecraft. It takes around 22.5 hours to send a radio signal to the spacecraft, and another 22.5 hours to receive one back.

Over the coming weeks, the Voyager 1 team will relocate the other affected portions of the software to different parts of the FDS memory, including portions related to the mission’s science data.

Voyager 1 launched in 1977, less than a month after its twin probe, Voyager 2, began its own journey to space. The probe ventured into interstellar space in August 2012, becoming the first spacecraft to leave the heliosphere. The twin spacecraft are the longest-running missions in history, and aside from a few communication glitches, the pair are doing pretty well for their age.

For more spaceflight in your life, follow us on X and bookmark Gizmodo’s dedicated Spaceflight page .

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Nasa voyager 1 making sense again after glitch in interstellar space.

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An illustration shows a Voyager spacecraft in space.

Humanity’s farthest-flung emissary is speaking clearly again after a tense five months of confusing communications. NASA’s Voyager 1 spacecraft—currently cruising in interstellar space—got in touch on April 20 with usable data on its health and status. That’s a triumph after a glitch in November caused the spacecraft to send back nothing but gibberish.

NASA’s official Voyager account on social media site X tweeted a simple message in celebration: “Hi, it's me.”

NASA shared a photo of the Voyager flight team celebrating the reception of the health and status data from the probe. The group has worked through some previous glitches, including another computer problem in 2022 . Technical issues are to be expected with an old machine like Voyager 1 that has weathered the demanding space environment for decades.

The Voyager 1 team had to play a long-distance game of detective with the elderly probe. NASA traced the problem to a single chip in the flight data subsystem, an onboard computer that prepares science and engineering data to be sent home. That chip held some of the FDS software code. “The loss of that code rendered the science and engineering data unusable,” said NASA in a statement on April 22. “Unable to repair the chip, the team decided to place the affected code elsewhere in the FDS memory.”

The FDS fix is complex and involves dividing and storing the code in different places. The team started with the code that lets Voyager 1 package up its engineering data. It worked. “During the coming weeks, the team will relocate and adjust the other affected portions of the FDS software,” NASA said. “These include the portions that will start returning science data.” NASA has turned off some of the probe’s instruments as it has aged, but it can still collect data on interstellar space .

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The spacecraft and its twin Voyager 2 launched in 1977 with the goal of studying our solar system. Voyager 1 visited Jupiter and Saturn and then kept on going and going. In 2012, it left our cosmic neighborhood and entered the space between stars. It was the first human-made object to leave our solar system. Voyager 2 later followed its sibling into interstellar space in 2018.

Voyager 1’s distance and age make it challenging to troubleshoot. It takes about 22.5 hours for a signal to cover the 15 billion miles between Earth and the probe. It takes just as long to receive a response back. Voyager 1’s initial mission was set to last for just four years. “Finding solutions to challenges the probes encounter often entails consulting original, decades-old documents written by engineers who didn’t anticipate the issues that are arising today,” NASA said in a December statement.

The Voyager missions will come to an end someday. NASA hopes to keep at least one instrument operating on each spacecraft until around 2025. The science data may dry up, but the probes could still stay in touch with home. “The two Voyager spacecraft could remain in the range of the Deep Space Network through about 2036, depending on how much power the spacecraft still have to transmit a signal back to Earth,” said NASA . The adventure isn’t over yet.

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NASA Decodes the Reason Behind Voyager 1's Garbled Transmissions

For months, NASA's Voyager team has been struggling to translate garbled messages from beyond our solar system. Voyager 1 has been responding to NASA's data requests with tangles of 1s and 0s, none of which have made sense to anyone at the agency. But now, thanks to a "poke command" issued in March, the spacecraft seems to have helped scientists identify the error behind its wonky transmissions. 

NASA had just managed to solve an issue with Voyager 1's attitude articulation and control system (AACS) in 2022 when a new glitch arose, jumbling the probe's flight data. This raw data is supposed to convey information about what Voyager 1's various scientific instruments have gleaned from remote regions of the Milky Way, but instead, it was just a mysterious stream of unintelligible numbers. Getting the spacecraft to return to its original "language" has been a challenge ever since, in part because most of the folks who originally worked on Voyager 1 are no longer alive .

In March, NASA sent Voyager 1 a poke command, or a command that directly modifies a system's memory addresses. Though poke commands are a fairly antiquated concept, they're occasionally useful for low-level memory control—a stone the Voyager team couldn't leave unturned. Their command prompted Voyager 1's system into using a different readout sequence for its software package than it typically defaults to, and about 22 hours later, NASA found itself with a new clue.

According to a Voyager mission blog post , activity from one portion of Voyager 1's flight data system (FDS) stood out from the probe's previous unreadable transmissions. A single engineer involved in NASA's Deep Space Network saw that the data contained a readout of Voyager 1's full FDS memory. This, the engineer noticed, offered the team an opportunity to compare and contrast Voyager 1's previous FDS readout with the latest snapshot of its inner workings.   

NASA has since used the decoded readout to determine that roughly 3 percent of the probe's memory is corrupted. This may explain why restarting the FDS didn't resolve the issue back in November: If a system's memory has degraded, turning that system off and back on again won't do anything to bring it back. Luckily, engineers at the Voyager mission think the corruption is confined to just one chip, which could make the issue easier to circumvent or resolve. 

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How are the Voyager spacecraft able to transmit radio messages so far?

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The two Voyage spacecraft certainly have had an amazing track record. They were sent to photograph planets like Jupiter, Saturn and Neptune and have just kept on going past the outer edge of the solar system. Voyager 1 is currently over 7 billion miles (about 11 billion kilometers) away from Earth and is still transmitting -- it takes about 10 hours for the signal to travel from the spacecraft to Earth!

The Voyager spacecraft use 23-watt radios. This is higher than the 3 watts a typical cell phone uses, but in the grand scheme of things it is still a low-power transmitter. Big radio stations on Earth transmit at tens of thousands of watts and they still fade out fairly quickly.

The key to receiving the signals is therefore not the power of the radio, but a combination of three other things:

• Very large antennas
• Directional antennas that point right at each other
• Radio frequencies without a lot of man-made interference on them

The antennas that the Voyager spacecraft use are big. You may have seen people who have large satellite dish antennas in their yards. These are typically 2 or 3 meters (6 to 10 feet) in diameter. The Voyager spacecraft has an antenna that is 3.7 meters (14 feet) in diameter, and it transmits to a 34 meter (100 feet or so) antenna on Earth. The Voyager antenna and the Earth antenna are pointed right at each other. When you compare your phone's stubby, little omni-directional antenna to a 34 meter directional antenna, you can see the main thing that makes a difference!

The Voyager satellites are also transmitting in the 8 GHz range , and there is not a lot of interference at this frequency. Therefore the antenna on Earth can use an extremely sensitive amplifier and still make sense of the faint signals it receives. Then when the earth antenna transmits back to the spacecraft, it uses extremely high power (tens of thousands of watts) to make sure the spacecraft gets the message.

Frequently Asked Questions

What role do earth's ground stations play in receiving signals from distant spacecraft like voyager, how has technology advanced to maintain communication with voyager as it moves further away.

Please copy/paste the following text to properly cite this HowStuffWorks.com article:

• The Contents
• The Making of
• 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

Did You Know?

The Voyager mission was officially approved in May 1972. Through the dedicated efforts of many skilled personnel for over three decades, the Voyagers have returned knowledge about the outer planets that had not existed in all of the preceding history of astronomy and planetary science. The Voyager spacecrafts are still performing like champs.

It must come as no surprise that there are many remarkable, "gee-whiz" facts associated with the various aspects of the Voyager mission. These tidbits have been summarized below in appropriate categories. Several may seem difficult to believe, but they are all true and accurate.

Overall Mission

The total cost of the Voyager mission from May 1972 through the Neptune encounter (including launch vehicles, radioactive power source (RTGs), and DSN tracking support) is 865 million dollars. At first, this may sound very expensive, but the fantastic returns are a bargain when we place the costs in the proper perspective. It is important to realize that:

• on a per-capita basis, this is only 8 cents per U.S. resident per year, or roughly half the cost of one candy bar each year since project inception. the entire cost of Voyager is a fraction of the daily interest on the U.S. national debt.
• A total of 11,000 workyears was devoted to the Voyager project through the Neptune encounter. This is equivalent to one-third the amount of effort estimated to complete the great pyramid at Giza to King Cheops.

A total of five trillion bits of scientific data had been returned to Earth by both Voyager spacecraft at the completion of the Neptune encounter. This represents enough bits to fill more than seven thousand music CDs.

The sensitivity of our deep-space tracking antennas located around the world is truly amazing. The antennas must capture Voyager information from a signal so weak that the power striking the antenna is only 10 exponent -16 watts (1 part in 10 quadrillion). A modern-day electronic digital watch operates at a power level 20 billion times greater than this feeble level.

Voyager Spacecraft

Each Voyager spacecraft comprises 65,000 individual parts. Many of these parts have a large number of "equivalent" smaller parts such as transistors. One computer memory alone contains over one million equivalent electronic parts, with each spacecraft containing some five million equivalent parts. Since a color TV set contains about 2500 equivalent parts, each Voyager has the equivalent electronic circuit complexity of some 2000 color TV sets.

Like the HAL computer aboard the ship Discovery from the famous science fiction story 2001: A Space Odyssey, each Voyager is equipped with computer programming for autonomous fault protection. The Voyager system is one of the most sophisticated ever designed for a deep-space probe. There are seven top-level fault protection routines, each capable of covering a multitude of possible failures. The spacecraft can place itself in a safe state in a matter of only seconds or minutes, an ability that is critical for its survival when round-trip communication times for Earth stretch to several hours as the spacecraft journeys to the remote outer solar system.

Both Voyagers were specifically designed and protected to withstand the large radiation dosage during the Jupiter swing-by. This was accomplished by selecting radiation-hardened parts and by shielding very sensitive parts. An unprotected human passenger riding aboard Voyager 1 during its Jupiter encounter would have received a radiation dose equal to one thousand times the lethal level.

The Voyager spacecraft can point its scientific instruments on the scan platform to an accuracy of better than one-tenth of a degree. This is comparable to bowling strike-after-strike ad infinitum, assuming that you must hit within one inch of the strike pocket every time. Such precision is necessary to properly center the narrow-angle picture whose square field-of-view would be equivalent to the width of a bowling pin.

To avoid smearing in Voyager's television pictures, spacecraft angular rates must be extremely small to hold the cameras as steady as possible during the exposure time. Each spacecraft is so steady that angular rates are typically 15 times slower than the motion of a clock's hour hand. But even this was not steady enough at Neptune, where light levels are 900 times fainter than those on Earth. Spacecraft engineers devised ways to make Voyager 30 times steadier than the hour hand on a clock.

The electronics and heaters aboard each nearly one-ton Voyager spacecraft can operate on only 400 watts of power, or roughly one-fourth that used by an average residential home in the western United States.

A set of small thrusters provides Voyager with the capability for attitude control and trajectory correction. Each of these tiny assemblies has a thrust of only three ounces. In the absence of friction, on a level road, it would take nearly six hours to accelerate a large car up to a speed of 48 km/h (30 mph) using one of the thrusters.

The Voyager scan platform can be moved about two axes of rotation. A thumb-sized motor in the gear train drive assembly (which turns 9000 revolutions for each single revolution of the scan platform) will have rotated five million revolutions from launch through the Neptune encounter. This is equivalent to the number of automobile crankshaft revolutions during a trip of 2725 km (1700 mi), about the distance from Boston,MA to Dallas,TX.

The Voyager gyroscopes can detect spacecraft angular motion as little as one ten-thousandth of a degree. The Sun's apparent motion in our sky moves over 40 times that amount in just one second.

The tape recorder aboard each Voyager has been designed to record and playback a great deal of scientific data. The tape head should not begin to wear out until the tape has been moved back and forth through a distance comparable to that across the United States. Imagine playing a two-hour video cassette on your home VCR once a day for the next 33 years, without a failure.

The Voyager magnetometers are mounted on a frail, spindly, fiberglass boom that was unfurled from a two-foot-long can shortly after the spacecraft left Earth. After the boom telescoped and rotated out of the cannister to an extension of nearly 13 meters (43 feet), the orientations of the magnetometer sensors were controlled to an accuracy better than two degrees.

Each Voyager used the enormous gravity field of Jupiter to be hurled on to Saturn, experiencing a Sun-relative speed increase of roughly 35,700 mph. As total energy within the solar system must be conserved, Jupiter was initially slowed in its solar orbit---but by only one foot per trillion years. Additional gravity-assist swing-bys of Saturn and Uranus were necessary for Voyager 2 to complete its Grand Tour flight to Neptune, reducing the trip time by nearly twenty years when compared to the unassisted Earth-to-Neptune route.

The Voyager delivery accuracy at Neptune of 100 km (62 mi), divided by the trip distance or arc length traveled of 7,128,603,456 km (4,429,508,700 mi), is equivalent to the feat of sinking a 3630 km (2260 mi) golf putt, assuming that the golfer can make a few illegal fine adjustments while the ball is rolling across this incredibly long green.

Voyager's fuel efficiency (in terms of mpg) is quite impressive. Even though most of the launch vehicle's 700 ton weight is due to rocket fuel, Voyager 2's great travel distance of 7.1 billion km (4.4 billion mi) from launch to Neptune resultsed in a fuel economy of about 13,000 km per liter (30,000 mi per gallon). As Voyager 2 streaked by Neptune and coasts out of the solar system, this fuel economy just got better and better!

The resolution of the Voyager narrow-angle television cameras is sharp enough to read a newspaper headline at a distance of 1 km (0.62 mi).

Pele, the largest of the volcanoes seen on Jupiter's moon Io, is throwing sulfur and sulfur-dioxide products to heights 30 times that of Mount Everest, and the fallout zone covers an area the size of France. The eruption of Mount St. Helens was but a tiny hiccup in comparison (admittedly, Io's surface-level gravity is some six times weaker than that of Earth).

The smooth water-ice surface of Jupiter's moon Europa may hide an ocean beneath, but some scientists believe any past oceans have turned to slush or ice. In 2010: Odyssey Two, Arthur C. Clarke wraps his story around the possibility of life developing within the oceans of Europa.

The rings of Saturn appeared to the Voyagers as a dazzling necklace of 10,000 strands. Trillions of ice particles and car-sized bergs race along each of the million-kilometer-long tracks, with the traffic flow orchestrated by the combined gravitational tugs of Saturn, a retinue of moons and moonlets, and even nearby ring particles. The rings of Saturn are so thin in proportion to their 171,000 km (106,000 mi) width that, if a full-scale model were to be built with the thickness of a phonograph record the model would have to measure four miles from its inner edge to its outer rim. An intricate tapestry of ring-particle patterns is created by many complex dynamic interactions that have spawned new theories of wave and particle motion.

Saturn's largest moon Titan was seen as a strange world with its dense atmosphere and variety of hydrocarbons that slowly fall upon seas of ethane and methane. To some scientists, Titan, with its principally nitrogen atmosphere, seemed like a small Earth whose evolution had long ago been halted by the arrival of its ice age, perhaps deep-freezing a few organic relics beneath its present surface.

The rings of Uranus are so dark that Voyager's challenge of taking their picture was comparable to the task of photographing a pile of charcoal briquettes at the foot of a Christmas tree, illuminated only by a 1 watt bulb at the top of the tree, using ASA-64 film. And Neptune light levels will be less than half those at Uranus.

Through the ages, astronomers have argued without agreeing on where the solar system ends. One opinion is that the boundary is where the Sun’s gravity no longer dominates – a point beyond the planets and beyond the Oort Cloud. This boundary is roughly about halfway to the nearest star, Proxima Centauri. Traveling at speeds of over 35,000 miles per hour, it will take the Voyagers nearly 40,000 years, and they will have traveled a distance of about two light years to reach this rather indistinct boundary.

But there is a more definitive and unambiguous frontier, which the Voyagers will approach and pass through. This is the heliopause, which is the boundary area between the solar and the interstellar wind. When Voyager 1 crosses the solar wind termination shock, it will have entered into the heliosheath, the turbulent region leading up to the heliopause. When the Voyagers cross the heliopause, hopefully while the spacecraft are still able to send science data to Earth, they will be in interstellar space even though they will still be a very long way from the “edge of the solar system”. Once Voyager is in interstellar space, it will be immersed in matter that came from explosions of nearby stars. So, in a sense, one could consider the heliopause as the final frontier.

Barring any serious spacecraft subsystem failures, the Voyagers may survive until the early twenty-first century (~ 2025), when diminishing power and hydrazine levels will prevent further operation. Were it not for these dwindling consumables and the possibility of losing lock on the faint Sun, our tracking antennas could continue to "talk" with the Voyagers for another century or two!