how many km is voyager 1 from earth

Voyager 1: 'The Spacecraft That Could' Hits New Milestone

Voyager 1, already the most distant human-made object in the cosmos, reaches 100 astronomical units from the sun on Tuesday, August 15 at 5:13 p.m. Eastern time (2:13 p.m. Pacific time).

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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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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.”

Adrienne So

Nena Farrell

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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Most distant spacecraft from Earth sends data to NASA for first time in 5 months

By Kerry Breen

Updated on: April 23, 2024 / 8:45 PM EDT / CBS News

The most distant spacecraft from Earth has resumed sending data after a five-month gap, NASA said Monday. 

NASA's Voyager 1 spacecraft was launched in 1977, about two weeks after the launch of its twin, Voyager 2. The spacecraft has spent over 45 years studying the outer solar system and has made flybys of Jupiter and Saturn and traveled more than 46,000,000,000 miles . 

In November 2023, the spacecraft stopped sending "readable science and engineering data," NASA said in a news release . Mission controllers were able to determine that Voyager 1 was still receiving commands from Earth and operating normally, but the science data could not be read and researchers did not know the status of the craft's onboard engineering systems. 

Last month, the craft's engineering team was able to confirm that the issue was related to one of the three onboard computers that make up Voyager 1's flight data subsystem. That system is what packages science and engineering data into a readable format before sending it to Earth. The team determined that "a single chip responsible for storing a portion of the (system's) memory," including some computer software code, wasn't working. 

The chip couldn't be repaired and the code was too large to place in one new location, NASA said, so the team worked to relocate the affected code into multiple sections of the flight data subsystem. It took weeks to repackage the code, NASA said, and last Thursday, the new location was communicated to Voyager 1. 

It takes about 22 and a half hours for a radio signal to reach Voyager 1 in interstellar space , or the space between stars, NASA said. On Saturday, the spacecraft's mission team received a response, confirming that the code modification had worked. 

Engineers celebrated receiving new data for the first time in almost half a year, but the work isn't done yet. NASA said that in the coming weeks, the mission team will "relocate and adjust the other affected portions" of the software, including portions that will start returning science data. Meanwhile, Voyager 2 continues to operate with no issues, and both craft will continue to report back on the distant reaches of the solar system. 

Kerry Breen is a reporter and news editor at CBSNews.com. A graduate of New York University's Arthur L. Carter School of Journalism, she previously worked at NBC News' TODAY Digital. She covers current events, breaking news and issues including substance use.

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Compute Voyager 1 ephemerides for any date and time between 01 Jan 2013 and 31 Dec 2099 and display the predicted position in an interactive sky map.

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How far away is voyager 1 from earth.

The distance of Voyager 1 from Earth is currently 24,334,079,478 kilometers, equivalent to 162.663274 Astronomical Units . Light takes 22 hours, 32 minutes and 49.7520 seconds to travel from Voyager 1 and arrive to us.

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The remarkable twin Voyager spacecraft continue to explore the outer reaches of the solar system decades after they completed their surveys of the Outer Planets.  Launched in 1977 (September 5 for Voyager 1 (V1) and August 20 for Voyager 2 (V2), whose trajectory took it past Jupiter after Voyager 1), the spacecraft pair made many fundamental discoveries as they flew past Jupiter (March 1979 for V1, July 1979 for V2) and Saturn (November 1980 for V1, August 1981 for V2).  The path of Voyager 2 past Saturn was targeted so that it continued within the plane of the solar system, allowing it to become the first spacecraft to visit Uranus (January 1986) and Neptune (August 1989).  Following the Neptune encounter, both spacecraft started a new phase of exploration under the intriguing title of the Voyager Interstellar Mission.

Five instruments continue to collect important measurements of magnetic fields, plasmas, and charged particles as both spacecraft explore different portions of the solar system beyond the orbits of the planets.  Voyager 1 is now more than 118 astronomical units (one AU is equal to the average orbital distance of Earth from the Sun) distant from the sun, traveling at a speed (relative to the sun) of 17.1 kilometers per second (10.6 miles per second).  Voyager 2 is now more than 96 AU from the sun, traveling at a speed of 15.5 kilometers per second (9.6 miles per second).  Both spacecraft are moving considerably faster than Pioneers 10 and 11, two earlier spacecraft that became the first robotic visitors to fly past Jupiter and Saturn in the mid-70s.

This processed color image of Jupiter was produced in 1990 by the U.S. Geological Survey from a Voyager image captured in 1979. The colors have been enhanced to bring out detail. Zones of light-colored, ascending clouds alternate with bands of dark, descending clouds. The clouds travel around the planet in alternating eastward and westward belts at speeds of up to 540 kilometers per hour. Tremendous storms as big as Earthly continents surge around the planet. The Great Red Spot (oval shape toward the lower-left) is an enormous anticyclonic storm that drifts along its belt, eventually circling the entire planet.

As seen in the night sky at Earth, Voyager 1 is within the confines of the constellation Ophiuchus, only slightly above the celestial equator; no telescope can see it, but radio contact is expected to be maintained for at least the next ten years.  Voyager 2 is within the bounds of the constellation Telescopium (which somehow sounds quite appropriate) in the far southern night sky.

Both spacecraft have already passed something called the Termination Shock † (December 2004 for V1, August 2007 for V2), where the solar wind slows as it starts to interact with the particles and fields present between the stars.  It is expected that both spacecraft will encounter the Heliopause, where the solar wind ceases as true interstellar space begins, from 10 to 20 years after crossing the Termination Shock.  Theories exist for what should be present in interstellar space, but the Voyagers will become the first man-made objects to go beyond the influences of the Sun, hopefully returning the first measurements of what it is like out there.  Each spacecraft is carrying a metal record with encoded sounds and sights from Earth, along with the needle needed to read the recordings, and simplified instructions for where the spacecraft came from, in case they are eventually discovered by intelligent extra-terrestrials.

Keep track of the Voyager spacecraft on the official  Voyager Interstellar Mission website or follow  @NASAVoyager2 on Twitter.    † The sun ejects a continuous stream of charged particles (electrons, protons, etc) that is collectively termed the solar wind.  The particles are traveling extremely fast and are dense enough to form a very tenuous atmosphere; the heliosphere represents the volume of space where the effects of the solar wind dominate over those of particles in interstellar space.  The solar wind particles are moving very much faster than the local speed of sound represented by their low volume density.  When the particles begin to interact with interstellar particles and fields (the interaction can be either physically running into other particles or experiencing an electromagnetic force resulting from a charged particle moving within a magnetic field), then they start to slow down.  The point at which they become subsonic (rather than their normal hypersonic speed) is the Termination Shock.

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

On Saturday, April 5, Voyager 1 finally "phoned home" and updated its NASA operating team about its health.

NASA's interstellar explorer Voyager 1 is finally communicating with ground control in an understandable way again. On Saturday (April 20), Voyager 1 updated ground control about its health status for the first time in 5 months. While the Voyager 1 spacecraft still isn't sending valid science data back to Earth, it is now returning usable information about the health and operating status of its onboard engineering systems. 

Thirty-five years after its launch in 1977, Voyager 1 became the first human-made object to leave the solar system and enter interstellar space . It was followed out of our cosmic quarters by its space-faring sibling, Voyager 2 , six years later in 2018. Voyager 2, thankfully, is still operational and communicating well with Earth. 

The two spacecraft remain the only human-made objects exploring space beyond the influence of the sun. However, on Nov. 14, 2023, after 11 years of exploring interstellar space and while sitting a staggering 15 billion miles (24 billion kilometers) from Earth, Voyager 1's binary code — computer language composed of 0s and 1s that it uses to communicate with its flight team at NASA — stopped making sense.

Related: We finally know why NASA's Voyager 1 spacecraft stopped communicating — scientists are working on a fix

In March, NASA's Voyager 1 operating team sent a digital "poke" to the spacecraft, prompting its flight data subsystem (FDS) to send a full memory readout back home.

This memory dump revealed to scientists and engineers that the "glitch" is the result of a corrupted code contained on a single chip representing around 3% of the FDS memory. The loss of this code rendered Voyager 1's science and engineering data unusable.

The NASA team can't physically repair or replace this chip, of course, but what they can do is remotely place the affected code elsewhere in the FDS memory. Though no single section of the memory is large enough to hold this code entirely, the team can slice it into sections and store these chunks separately. To do this, they will also have to adjust the relevant storage sections to ensure the addition of this corrupted code won't cause those areas to stop operating individually, or working together as a whole. In addition to this, NASA staff will also have to ensure any references to the corrupted code's location are updated.

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On April 18, 2024, the team began sending the code to its new location in the FDS memory. This was a painstaking process, as a radio signal takes 22.5 hours to traverse the distance between Earth and Voyager 1, and it then takes another 22.5 hours to get a signal back from the craft. 

By Saturday (April 20), however, the team confirmed their modification had worked. For the first time in five months, the scientists were able to communicate with Voyager 1 and check its health. Over the next few weeks, the team will work on adjusting the rest of the FDS software and aim to recover the regions of the system that are responsible for packaging and returning vital science data from beyond the limits of the solar system.

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].

Robert Lea is a science journalist in the U.K. whose articles have been published in Physics World, New Scientist, Astronomy Magazine, All About Space, Newsweek and ZME Science. He also writes about science communication for Elsevier and the European Journal of Physics. Rob holds a bachelor of science degree in physics and astronomy from the U.K.’s Open University. Follow him on Twitter @sciencef1rst.

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• Robb62 'V'ger must contact the creator. Reply
• Holy HannaH! Couldn't help but think that "repair" sounded extremely similar to the mechanics of DNA and the evolution of life. Reply
• Torbjorn Larsson *Applause* indeed, thanks to the Voyager teams for the hard work! Reply
• SpaceSpinner I notice that the article says that it has been in space for 35 years. Either I have gone back in time 10 years, or their AI is off by 10 years. V-*ger has been captured! Reply

Admin said: On Saturday, April 5, Voyager 1 finally "phoned home" and updated its NASA operating team about its health. The interstellar explorer is back in touch after five months of sending back nonsense data. NASA's Voyager 1 spacecraft finally phones home after 5 months of no contact : Read more

evw said: I'm incredibly grateful for the persistence and dedication of the Voyagers' teams and for the amazing accomplishments that have kept these two spacecrafts operational so many years beyond their expected lifetimes. V-1 was launched when I was 25 years young; I was nearly delirious with joy. Exploring the physical universe captivated my attention while I was in elementary school and has kept me mesmerized since. I'm very emotional writing this note, thinking about what amounts to a miracle of technology and longevity in my eyes. BRAVO!!! THANK YOU EVERYONE PAST & PRESENT!!!

• EBairead I presume it's Fortran. Well done all. Reply

SpaceSpinner said: I notice that the article says that it has been in space for 35 years. Either I have gone back in time 10 years, or their AI is off by 10 years. V-*ger has been captured!

EBairead said: I presume it's Fortran. Well done all.

• View All 13 Comments

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September 12, 2013

Voyager 1 Finally Leaves Solar System—for Real This Time

After much debate over the murky boundary of interstellar space, a solar eruption gives scientists the evidence to say Voyager 1 has finally crossed it

By Clara Moskowitz

Voyager 1 was starting to get a reputation as the spacecraft that cried wolf, after scientists repeatedly claimed it was leaving the solar system, only to change their minds and say it wasn’t quite there yet . Now researchers say new evidence shows Voyager really has departed the sun’s sphere of influence and become the first man-made object to reach interstellar space.

Voyager 1, launched in 1977, is speeding away from us, traveling about 3.5 times the Earth–sun distance every year. The probe is now about 18.2 billion kilometers from Earth, farther away than anything human beings have sent into space. (Its sister spacecraft, Voyager 2, launched more than a month earlier, took a more circuitous path from Earth and is now about 14.8 billion kilometers away.)

Scientists have long been expecting Voyager 1 to exit the bubble of space containing particles from the sun, called the heliosphere, and enter a region where particles are much more plentiful and come from ancient explosions of other stars. But because Voyager 1 has lost its ability to measure this particle plasma, there was no easy way to tell when the transition had occurred .

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A boon came from an eruption on the sun in March 2012, which sent waves of solar material out into space. When this ejection reached Voyager 1 13 months later in April 2013, it set the local plasma vibrating. Voyager 1's plasma wave instrument (separate from the defunct plasma particle detector) was able to measure the pitch of these vibrations, which in turn reflected the density of plasma around the spacecraft. The results show that Voyager 1 is surrounded by plasma more than 40 times denser than it encountered earlier, when it was in the heliosphere. “Because there’s no other possible conclusion, I think we’re forced to and obliged to conclude that we’re truly in the interstellar medium,” physicist Gary Zank of the University of Alabama in Huntsville said during a press conference today.

Based on abrupt changes in the apparent plasma density around the spacecraft, the researchers were even able to pinpoint August 25, 2012 as the most likely date that Voyager 1 left the solar system , crossing the heliopause, the boundary between the heliosphere and the interstellar medium.

The “little spacecraft that could,” in the words of project manager Suzanne Dodd of the NASA Jet Propulsion Laboratory in Pasadena, Calif., is getting old in years and is technologically weak: the average smartphone has thousands of times more memory than the spacecraft. Yet most of Voyager 1’s instruments still work, and they continue to send signals back to Earth. The team estimates the probe still has enough power from its plutonium power plant to operate all its instruments through 2020, when it will begin shutting them off one by one, until it goes dark in 2025. That still gives Voyager 1 more than a decade to study the realm of the universe it has entered. “It marks the beginning of a new era of exploration for Voyager: the exploration of the space between the stars,” said Ed Stone, Voyager’s longtime project scientist.

The new findings represent a turnaround for the Voyager team, which as recently as June predicted the spacecraft may have years to go before it reached interstellar space. But the latest data remove most of the team members’ doubts, Stone said.

The new report, published online today in Science, also agrees with the conclusions of a separate paper claiming Voyager 1 had left the solar system, based on magnetic field data, which was published August 14 in The Astrophysical Journal Letters. The lead author of that paper, University of Maryland, College Park, physicist Marc Swisdak, says the two projects are complementary. “I thought the authors make an excellent case for their measurements and their interpretation,” Swisdak says.

Over the course of 36 years, between the two of them, the Voyager probes have visited all the outer planets of the solar system and discovered 23 moons around these worlds. They also each carry time capsules in the form of phonograph records loaded with recordings of music, natural sounds, voice greetings in 56 languages, and photographs and diagrams of life on Earth. Voyager 1 is on a course that should eventually take it within 1.6 light-years of a star called AC+79 3888, which lies in the constellation of Camelopardalis. It’s due to arrive in about 40,000 years, long after the spacecraft loses its ability to tell whomever is on Earth what comes of that encounter.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

The hard work paid off.

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

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

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

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

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

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

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

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

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

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

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Voyager 1 whizzes through interstellar space at 17 kilometers per second.

On 14 November 2023, NASA’s interstellar space probe Voyager 1 began sending gibberish back to Earth. For five months, the spacecraft transmitted unusable data equivalent to a dial tone.

In March, engineers discovered the cause of the communication snafu: a stuck bit in one of the chips comprising part of Voyager’s onboard memory. The chip contained lines of code used by the flight data subsystem (FDS), one of three computers aboard the spacecraft and the one that is responsible for collecting and packaging data before sending it back to Earth.

JPL engineers sent a command through the Deep Space Network on 18 April to relocate the affected section of code to another part of the spacecraft’s memory, hoping to fix the glitch in the archaic computer system. Roughly 22.5 hours later, the radio signal reached Voyager in interstellar space, and by the following day it was clear the command had worked. Voyager began returning useful data again on 20 April.

NASA engineers managed to diagnose and repair Voyager 1 from 24 billion kilometers away—all while working within the constraints of the vintage technology. “We had some people left that we could rely on [who] could remember working on bits of the hardware,” says project scientist Linda Spilker . “But a lot of it was going back through old memos, like an archeological dig to try and find information on the best way to proceed.”

Minuscule Memory

Voyager 1 and its twin, Voyager 2—which also remains operational—were launched nearly 50 years ago, in 1977, to tour the solar system. Both spacecraft far surpassed their original missions of visiting Jupiter and Saturn, and in 2012, entered interstellar space .

“That mission literally rewrote the textbooks on the solar system,” says Jim Bell , a planetary scientist at Arizona State University and author of a book recounting 40 years of the mission. “We’ve never sent anything out that far, so every bit of data they send back is new.” The 1960s and 1970s technology, on the other hand, is now ancient.

Decades after the tech went out of vogue, the FDS still uses assembly language and 16-bit words . “These are two positively geriatric spacecraft,” says Todd Barber , a propulsion engineer for Voyager. Working to fix the issues, he says, is “like palliative care.”

To first diagnose the issue, NASA’s engineers first tried turning on and off different instruments, says Spilker. When that proved unsuccessful, they initiated a full memory readout of the FDS. “That’s what led to us finding that piece of hardware that had failed and that 256-bit chunk of memory,” she says. In one chip, the engineers found a stuck bit, fixed at the same binary value. It became clear that the chip was irreparable, so the team had to identify and relocate the affected code.

However, no single location was large enough to accommodate the extra 256 bits. “The size of the memory was the biggest challenge in this anomaly,” says Spilker. Voyager’s computers each have a mere 69.63 kilobytes of memory.

To begin fixing the issue, the team searched for corners of Voyager’s memory to place segments of code that would allow for the return of engineering data, which includes information about the status of science instruments and the spacecraft itself. One way the engineers freed up extra space was by identifying processes no longer used. For example, Voyager was programmed with several data modes—the rate at which data is sent back to Earth—because the spacecraft could transmit data much faster when it was closer to Earth. At Jupiter, the spacecraft transmitted data at 115.2 kilobits per second; now, that rate has slowed to 40 bits per second, and faster modes can be overwritten. However, the engineers have to be careful to ensure they don’t delete code that is used by multiple data modes.

Having successfully returned engineering data, the team is working to relocate the rest of the affected code in the coming weeks. “We’re having to look a little harder to find the space and make some key decisions about what to overwrite,” says Spilker. When their work is completed, the Voyager team hopes to return new science data, though unfortunately, all data from the anomaly period was lost.

Built to Last

The cause of the stuck bit is a mystery, but it’s likely the chip either wore out with age or was hit by a highly energetic particle from a cosmic ray. Having entered interstellar space, “Voyager is out bathed in the cosmic rays,” Spilker says. Luckily, the spacecraft was built to take it, with its electronic components shielded from the large amount of radiation present at Jupiter. “That’s serving us quite well now in the interstellar medium.”

When Voyager was built, the 12-year trip to Uranus and Neptune alone was a “seemingly impossible goal for a 1977 launch,” says Barber. The longevity of Voyager is a testament of its engineering, which accounted for many contingencies and added redundancy. The mission also included several firsts, for example, as the first spacecraft with computers able to hold data temporarily using volatile CMOS memory. (An 8-track digital tape recorder onboard stores data when collected at a high rate.)

Importantly, it was also the first mission with a reprogrammable computer. “We take it for granted now,” Bell says, but before Voyager, it wasn’t possible to adjust software in-flight. This capability proved essential when the mission was extended, as well as when issues arise.

Going forward, the Voyager team expects to encounter additional problems in the aging spacecraft—though they hope to make it to the 50-year anniversary before the next one. “With each anomaly, we just learn more about how to work with the spacecraft and are just amazed at the capabilities that the engineers built into it using that 1960s and ’70s technology,” Spilker says. “It’s just amazing.”

• 50 Years Later, This Apollo-Era Antenna Still Talks to Voyager 2 ›
• Voyager 1 Hasn't Really Left The Solar System, But That's OK ›
• Mission Status - Voyager ›
• Voyager 1 ›

Gwendolyn Rak is a contributor to IEEE Spectrum .

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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.

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Jupiter Facts

Jupiter is a world of extremes. It's the largest planet in our solar system – if it were a hollow shell, 1,000 Earths could fit inside. It's also the oldest planet, forming from the dust and gases left over from the Sun's formation 4.5 billion years ago. But it has the shortest day in the solar system, taking only 10.5 hours to spin around once on its axis.

Introduction

Jupiter's signature stripes and swirls are actually cold, windy clouds of ammonia and water, floating in an atmosphere of hydrogen and helium. The dark orange stripes are called belts, while the lighter bands are called zones, and they flow east and west in opposite directions. Jupiter’s iconic Great Red Spot is a giant storm bigger than Earth that has raged for hundreds of years.

The king of planets was named for Jupiter, king of the gods in Roman mythology. Most of its moons are also named for mythological characters, figures associated with Jupiter or his Greek counterpart, Zeus.

Jupiter, being the biggest planet, gets its name from the king of the ancient Roman gods.

Potential for Life

Jupiter’s environment is probably not conducive to life as we know it. The temperatures, pressures, and materials that characterize this planet are most likely too extreme and volatile for organisms to adapt to.

While planet Jupiter is an unlikely place for living things to take hold, the same is not true of some of its many moons. Europa is one of the likeliest places to find life elsewhere in our solar system. There is evidence of a vast ocean just beneath its icy crust, where life could possibly be supported.

Size and Distance

With a radius of 43,440.7 miles (69,911 kilometers), Jupiter is 11 times wider than Earth. If Earth were the size of a grape, Jupiter would be about as big as a basketball.

From an average distance of 484 million miles (778 million kilometers), Jupiter is 5.2 astronomical units away from the Sun. One astronomical unit (abbreviated as AU), is the distance from the Sun to Earth. From this distance, it takes sunlight 43 minutes to travel from the Sun to Jupiter.

Orbit and Rotation

Jupiter has the shortest day in the solar system. One day on Jupiter takes only about 10 hours (the time it takes for Jupiter to rotate or spin around once), and Jupiter makes a complete orbit around the Sun (a year in Jovian time) in about 12 Earth years (4,333 Earth days).

Its equator is tilted with respect to its orbital path around the Sun by just 3 degrees. This means Jupiter spins nearly upright and does not have seasons as extreme as other planets do.

With four large moons and many smaller moons, Jupiter forms a kind of miniature solar system.

Jupiter has 95 moons that are officially recognized by the International Astronomical Union. The four largest moons – Io, Europa, Ganymede, and Callisto – were first observed by the astronomer Galileo Galilei in 1610 using an early version of the telescope. These four moons are known today as the Galilean satellites, and they're some of the most fascinating destinations in our solar system.

Io is the most volcanically active body in the solar system. Ganymede is the largest moon in the solar system (even bigger than the planet Mercury). Callisto’s very few small craters indicate a small degree of current surface activity. A liquid-water ocean with the ingredients for life may lie beneath the frozen crust of Europa, the target of NASA's Europa Clipper mission slated to launch in 2024.

› More on Jupiter's Moons

Discovered in 1979 by NASA's Voyager 1 spacecraft, Jupiter's rings were a surprise. The rings are composed of small, dark particles, and they are difficult to see except when backlit by the Sun. Data from the Galileo spacecraft indicate that Jupiter's ring system may be formed by dust kicked up as interplanetary meteoroids smash into the giant planet's small innermost moons.

Jupiter took shape along with rest of the solar system about 4.5 billion years ago. Gravity pulled swirling gas and dust together to form this gas giant. Jupiter took most of the mass left over after the formation of the Sun, ending up with more than twice the combined material of the other bodies in the solar system. In fact, Jupiter has the same ingredients as a star, but it did not grow massive enough to ignite.

About 4 billion years ago, Jupiter settled into its current position in the outer solar system, where it is the fifth planet from the Sun.

The composition of Jupiter is similar to that of the Sun – mostly hydrogen and helium. Deep in the atmosphere, pressure and temperature increase, compressing the hydrogen gas into a liquid. This gives Jupiter the largest ocean in the solar system – an ocean made of hydrogen instead of water. Scientists think that, at depths perhaps halfway to the planet's center, the pressure becomes so great that electrons are squeezed off the hydrogen atoms, making the liquid electrically conducting like metal. Jupiter's fast rotation is thought to drive electrical currents in this region, with the spinning of the liquid metallic hydrogen acting like a dynamo, generating the planet's powerful magnetic field.

Deeper down, Jupiter's central core had long been a mystery. Scientists theorized Jupiter was a mostly homogeneous mix of hydrogen and helium gases, surrounding a small, solid core of heavier elements – ice, rock, and metal formed from debris and small objects swirling around that area of the embryonic solar system 4 billion years ago.

NASA’s Juno spacecraft, measuring Jupiter’s gravity and magnetic field, found data suggesting the core is much larger than expected, and not solid. Instead, it’s partially dissolved, with no clear separation from the metallic hydrogen around it, leading researchers to describe the core as dilute, or “fuzzy.”

As a gas giant, Jupiter doesn’t have a true surface. The planet is mostly swirling gases and liquids. While a spacecraft would have nowhere to land on Jupiter, it wouldn’t be able to fly through unscathed either. The extreme pressures and temperatures deep inside the planet crush, melt, and vaporize spacecraft trying to fly into the planet.

Jupiter's appearance is a tapestry of colorful stripes and spots – the cloud bands that encircle the planet, and the cyclonic storms dotting it from pole to pole. The gas planet likely has three distinct cloud layers in its "skies" that, taken together, span about 44 miles (71 kilometers). The top cloud is probably made of ammonia ice, while the middle layer is likely made of ammonium hydrosulfide crystals. The innermost layer may be made of water ice and vapor.

The vivid colors you see in thick bands across Jupiter may be plumes of sulfur and phosphorus-containing gases rising from the planet's warmer interior. Jupiter's fast rotation – spinning once every 10 hours – creates strong jet streams, separating its clouds into dark belts and bright zones across long stretches.

With no solid surface to slow them down, Jupiter's spots can persist for many years. Stormy Jupiter is swept by over a dozen prevailing winds, some reaching up to 335 miles per hour (539 kilometers per hour) at the equator. The Great Red Spot, a swirling oval of clouds twice as wide as Earth, has been observed on the giant planet for more than 300 years. More recently, three smaller ovals merged to form the Little Red Spot, about half the size of its larger cousin.

Findings from NASA’s Juno probe released in October 2021 provide a fuller picture of what’s going on below those clouds. Data from Juno shows that Jupiter’s cyclones are warmer on top, with lower atmospheric densities, while they are colder at the bottom, with higher densities. Anticyclones, which rotate in the opposite direction, are colder at the top but warmer at the bottom.

The findings also indicate these storms are far taller than expected, with some extending 60 miles (100 kilometers) below the cloud tops and others, including the Great Red Spot, extending over 200 miles (350 kilometers). This surprising discovery demonstrates that the vortices cover regions beyond those where water condenses and clouds form, below the depth where sunlight warms the atmosphere.

The height and size of the Great Red Spot mean the concentration of atmospheric mass within the storm potentially could be detectable by instruments studying Jupiter’s gravity field. Two close Juno flybys over Jupiter’s most famous spot provided the opportunity to search for the storm’s gravity signature and complement the other results on its depth.

With their gravity data, the Juno team was able to constrain the extent of the Great Red Spot to a depth of about 300 miles (500 kilometers) below the cloud tops.

Belts and Zones In addition to cyclones and anticyclones, Jupiter is known for its distinctive belts and zones – white and reddish bands of clouds that wrap around the planet. Strong east-west winds moving in opposite directions separate the bands. Juno previously discovered that these winds, or jet streams, reach depths of about 2,000 miles (roughly 3,200 kilometers). Researchers are still trying to solve the mystery of how the jet streams form. Data collected by Juno during multiple passes reveal one possible clue: that the atmosphere’s ammonia gas travels up and down in remarkable alignment with the observed jet streams.

Juno’s data also shows that the belts and zones undergo a transition around 40 miles (65 kilometers) beneath Jupiter’s water clouds. At shallow depths, Jupiter’s belts are brighter in microwave light than the neighboring zones. But at deeper levels, below the water clouds, the opposite is true – which reveals a similarity to our oceans.

Polar Cyclones Juno previously discovered polygonal arrangements of giant cyclonic storms at both of Jupiter’s poles – eight arranged in an octagonal pattern in the north and five arranged in a pentagonal pattern in the south. Over time, mission scientists determined these atmospheric phenomena are extremely resilient, remaining in the same location.

Juno data also indicates that, like hurricanes on Earth, these cyclones want to move poleward, but cyclones located at the center of each pole push them back. This balance explains where the cyclones reside and the different numbers at each pole.

Magnetosphere

The Jovian magnetosphere is the region of space influenced by Jupiter's powerful magnetic field. It balloons 600,000 to 2 million miles (1 to 3 million kilometers) toward the Sun (seven to 21 times the diameter of Jupiter itself) and tapers into a tadpole-shaped tail extending more than 600 million miles (1 billion kilometers) behind Jupiter, as far as Saturn's orbit. Jupiter's enormous magnetic field is 16 to 54 times as powerful as that of the Earth. It rotates with the planet and sweeps up particles that have an electric charge. Near the planet, the magnetic field traps swarms of charged particles and accelerates them to very high energies, creating intense radiation that bombards the innermost moons and can damage spacecraft.

Jupiter's magnetic field also causes some of the solar system's most spectacular aurorae at the planet's poles.

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