voyager 1 voice recording

What Is on Voyager’s Golden Record?

From a whale song to a kiss, the time capsule sent into space in 1977 had some interesting contents

Megan Gambino

Senior Editor

“I thought it was a brilliant idea from the beginning,” says Timothy Ferris. Produce a phonograph record containing the sounds and images of humankind and fling it out into the solar system.

By the 1970s, astronomers Carl Sagan and Frank Drake already had some experience with sending messages out into space. They had created two gold-anodized aluminum plaques that were affixed to the Pioneer 10 and Pioneer 11 spacecraft. Linda Salzman Sagan, an artist and Carl’s wife, etched an illustration onto them of a nude man and woman with an indication of the time and location of our civilization.

The “Golden Record” would be an upgrade to Pioneer’s plaques. Mounted on Voyager 1 and Voyager 2, twin probes launched in 1977, the two copies of the record would serve as time capsules and transmit much more information about life on Earth should extraterrestrials find it.

NASA approved the idea. So then it became a question of what should be on the record. What are humanity’s greatest hits? Curating the record’s contents was a gargantuan task, and one that fell to a team including the Sagans, Drake, author Ann Druyan, artist Jon Lomberg and Ferris, an esteemed science writer who was a friend of Sagan’s and a contributing editor to Rolling Stone .

The exercise, says Ferris, involved a considerable number of presuppositions about what aliens want to know about us and how they might interpret our selections. “I found myself increasingly playing the role of extraterrestrial,” recounts Lomberg in Murmurs of Earth , a 1978 book on the making of the record. When considering photographs to include, the panel was careful to try to eliminate those that could be misconstrued. Though war is a reality of human existence, images of it might send an aggressive message when the record was intended as a friendly gesture. The team veered from politics and religion in its efforts to be as inclusive as possible given a limited amount of space.

Over the course of ten months, a solid outline emerged. The Golden Record consists of 115 analog-encoded photographs, greetings in 55 languages, a 12-minute montage of sounds on Earth and 90 minutes of music. As producer of the record, Ferris was involved in each of its sections in some way. But his largest role was in selecting the musical tracks. “There are a thousand worthy pieces of music in the world for every one that is on the record,” says Ferris. I imagine the same could be said for the photographs and snippets of sounds.

The following is a selection of items on the record:

Silhouette of a Male and a Pregnant Female

The team felt it was important to convey information about human anatomy and culled diagrams from the 1978 edition of The World Book Encyclopedia. To explain reproduction, NASA approved a drawing of the human sex organs and images chronicling conception to birth. Photographer Wayne F. Miller’s famous photograph of his son’s birth, featured in Edward Steichen’s 1955 “Family of Man” exhibition, was used to depict childbirth. But as Lomberg notes in Murmurs of Earth , NASA vetoed a nude photograph of “a man and a pregnant woman quite unerotically holding hands.” The Golden Record experts and NASA struck a compromise that was less compromising— silhouettes of the two figures and the fetus positioned within the woman’s womb.

DNA Structure

At the risk of providing extraterrestrials, whose genetic material might well also be stored in DNA, with information they already knew, the experts mapped out DNA’s complex structure in a series of illustrations.

Demonstration of Eating, Licking and Drinking

When producers had trouble locating a specific image in picture libraries maintained by the National Geographic Society, the United Nations, NASA and Sports Illustrated , they composed their own. To show a mouth’s functions, for instance, they staged an odd but informative photograph of a woman licking an ice-cream cone, a man taking a bite out of a sandwich and a man drinking water cascading from a jug.

Olympic Sprinters

Images were selected for the record based not on aesthetics but on the amount of information they conveyed and the clarity with which they did so. It might seem strange, given the constraints on space, that a photograph of Olympic sprinters racing on a track made the cut. But the photograph shows various races of humans, the musculature of the human leg and a form of both competition and entertainment.

Photographs of huts, houses and cityscapes give an overview of the types of buildings seen on Earth. The Taj Mahal was chosen as an example of the more impressive architecture. The majestic mausoleum prevailed over cathedrals, Mayan pyramids and other structures in part because Mughal Emperor Shah Jahan built it in honor of his late wife, Mumtaz Mahal, and not a god.

Golden Gate Bridge

Three-quarters of the record was devoted to music, so visual art was less of a priority. A couple of photographs by the legendary landscape photographer Ansel Adams were selected, however, for the details captured within their frames. One, of the Golden Gate Bridge from nearby Baker Beach, was thought to clearly show how a suspension bridge connected two pieces of land separated by water. The hum of an automobile was included in the record’s sound montage, but the producers were not able to overlay the sounds and images.

A Page from a Book

An excerpt from a book would give extraterrestrials a glimpse of our written language, but deciding on a book and then a single page within that book was a massive task. For inspiration, Lomberg perused rare books, including a first-folio Shakespeare, an elaborate edition of Chaucer from the Renaissance and a centuries-old copy of Euclid’s  Elements  (on geometry), at the Cornell University Library. Ultimately, he took MIT astrophysicist Philip Morrison’s suggestion: a  page  from Sir Isaac Newton’s  System of the World , where the means of launching an object into orbit is described for the very first time.

Greeting from Nick Sagan

To keep with the spirit of the project, says Ferris, the wordings of the 55 greetings were left up to the speakers of the languages. In  Burmese , the message was a simple, “Are you well?” In  Indonesian , it was, “Good night ladies and gentlemen. Goodbye and see you next time.” A woman speaking the Chinese dialect of  Amoy  uttered a welcoming, “Friends of space, how are you all? Have you eaten yet? Come visit us if you have time.” It is interesting to note that the final greeting, in  English , came from then-6-year-old Nick Sagan, son of Carl and Linda Salzman Sagan. He said, “Hello from the children of planet Earth.”

Whale Greeting

Biologist Roger Payne provided a whale song (“the most beautiful whale greeting,” he said, and “the one that should last forever”) captured with hydrophones off the coast of Bermuda in 1970. Thinking that perhaps the whale song might make more sense to aliens than to humans, Ferris wanted to include more than a slice and so mixed some of the song behind the greetings in different languages. “That strikes some people as hilarious, but from a bandwidth standpoint, it worked quite well,” says Ferris. “It doesn’t interfere with the greetings, and if you are interested in the whale song, you can extract it.”

Reportedly, the trickiest sound to record was a  kiss . Some were too quiet, others too loud, and at least one was too disingenuous for the team’s liking. Music producer Jimmy Iovine kissed his arm. In the end, the kiss that landed on the record was actually one that Ferris planted on Ann Druyan’s cheek.

Druyan had the idea to record a person’s brain waves, so that should extraterrestrials millions of years into the future have the technology, they could decode the individual’s thoughts. She was the guinea pig. In an hour-long session hooked to an EEG at New York University Medical Center, Druyan meditated on a series of prepared thoughts. In  Murmurs of Earth , she admits that “a couple of irrepressible facts of my own life” slipped in. She and Carl Sagan had gotten engaged just days before, so a love story may very well be documented in her neurological signs. Compressed into a minute-long segment, the  brain waves  sound, writes Druyan, like a “string of exploding firecrackers.”

Georgian Chorus—“Tchakrulo”

The team discovered a beautiful recording of “Tchakrulo” by Radio Moscow and wanted to include it, particularly since Georgians are often credited with introducing polyphony, or music with two or more independent melodies, to the Western world. But before the team members signed off on the tune, they had the lyrics translated. “It was an old song, and for all we knew could have celebrated bear-baiting,” wrote Ferris in  Murmurs of Earth . Sandro Baratheli, a Georgian speaker from Queens, came to the rescue. The word “tchakrulo” can mean either “bound up” or “hard” and “tough,” and the song’s narrative is about a peasant protest against a landowner.

Chuck Berry’s “Johnny B. Goode”

According to Ferris, Carl Sagan had to warm up to the idea of including Chuck Berry’s 1958 hit “Johnny B. Goode” on the record, but once he did, he defended it against others’ objections. Folklorist Alan Lomax was against it, arguing that rock music was adolescent. “And Carl’s brilliant response was, ‘There are a lot of adolescents on the planet,’” recalls Ferris.

On April 22, 1978,  Saturday Night Live  spoofed the Golden Record in a  skit  called “Next Week in Review.” Host Steve Martin played a psychic named Cocuwa, who predicted that  Time  magazine would reveal, on the following week’s cover, a four-word message from aliens. He held up a mock cover, which read, “Send More Chuck Berry.”

More than four decades later, Ferris has no regrets about what the team did or did not include on the record. “It means a lot to have had your hand in something that is going to last a billion years,” he says. “I recommend it to everybody. It is a healthy way of looking at the world.”

According to the writer, NASA approached him about producing another record but he declined. “I think we did a good job once, and it is better to let someone else take a shot,” he says.

So, what would you put on a record if one were being sent into space today?

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Megan Gambino | | READ MORE

Megan Gambino is a senior web editor for Smithsonian magazine.

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Hear the Eerie Sounds of Interstellar Space Captured by NASA’s Voyager

By Jet Propulsion Laboratory May 12, 2021

An illustration depicting one of NASA’s twin Voyager spacecraft. Both Voyagers have entered interstellar space, or the space outside our Sun’s heliosphere. Credit: NASA/JPL-Caltech

As NASA’s Voyager 1 Surveys Interstellar Space, Its Density Measurements Are Making Waves

In the sparse collection of atoms that fills interstellar space, Voyager 1 has measured a long-lasting series of waves where it previously only detected sporadic bursts.

Until recently, every spacecraft in history had made all of its measurements inside our heliosphere, the magnetic bubble inflated by our Sun. But on August 25, 2012, NASA ’s Voyager 1 changed that. As it crossed the heliosphere’s boundary , it became the first human-made object to enter – and measure – interstellar space. Now eight years into its interstellar journey, a close listen of Voyager 1’s data is yielding new insights into what that frontier is like.

If our heliosphere is a ship sailing interstellar waters, Voyager 1 is a life raft just dropped from the deck, determined to survey the currents. For now, any rough waters it feels are mostly from our heliosphere’s wake. But farther out, it will sense the stirrings from sources deeper in the cosmos. Eventually, our heliosphere’s presence will fade from its measurements completely.

This graphic from October 20218 shows the position of the Voyager 1 and Voyager 2 probes relative to the heliosphere, a protective bubble created by the Sun that extends well past the orbit of Pluto. Voyager 1 crossed the heliopause, or the edge of the heliosphere, in 2012. Voyager 2 is still in the heliosheath, or the outermost part of the heliosphere. (NASA’s Voyager 2 spacecraft entered interstellar space in November 2018 .) Credit: NASA/JPL-Caltech

“We have some ideas about how far Voyager will need to get to start seeing more pure interstellar waters, so to speak,” said Stella Ocker, a Ph.D. student at Cornell University in Ithaca, New York, and the newest member of the Voyager team. “But we’re not entirely sure when we’ll reach that point.”

Ocker’s new study, published on Monday in Nature Astronomy , reports what may be the first continuous measurement of the density of material in interstellar space. “This detection offers us a new way to measure the density of interstellar space and opens up a new pathway for us to explore the structure of the very nearby interstellar medium,” Ocker said.

When one pictures the stuff between the stars – astronomers call it the “interstellar medium,” a spread-out soup of particles and radiation – one might reimagine a calm, silent, serene environment. That would be a mistake.

“I have used the phrase ‘the quiescent interstellar medium’ – but you can find lots of places that are not particularly quiescent,” said Jim Cordes, space physicist at Cornell and co-author of the paper.

Like the ocean, the interstellar medium is full of turbulent waves. The largest come from our galaxy’s rotation, as space smears against itself and sets forth undulations tens of light-years across. Smaller (though still gigantic) waves rush from supernova blasts, stretching billions of miles from crest to crest. The smallest ripples are usually from our own Sun, as solar eruptions send shockwaves through space that permeate our heliosphere’s lining.

These crashing waves reveal clues about the density of the interstellar medium – a value that affects our understanding of the shape of our heliosphere, how stars form, and even our own location in the galaxy. As these waves reverberate through space, they vibrate the electrons around them, which ring out at characteristic frequencies depending on how crammed together they are. The higher the pitch of that ringing, the higher the electron density. Voyager 1’s Plasma Wave Subsystem – which includes two “bunny ear” antennas sticking out 30 feet (10 meters) behind the spacecraft – was designed to hear that ringing.

An illustration of NASA’s Voyager spacecraft showing the antennas used by the Plasma Wave Subsystem and other instruments. Credit: NASA/JPL-Caltech

In November 2012, three months after exiting the heliosphere, Voyager 1 heard interstellar sounds for the first time (see video above). Six months later, another “whistle” appeared – this time louder and even higher pitched. The interstellar medium appeared to be getting thicker, and quickly.

These momentary whistles continue at irregular intervals in Voyager’s data today. They’re an excellent way to study the interstellar medium’s density, but it does take some patience.

“They’ve only been seen about once a year, so relying on these kinds of fortuitous events meant that our map of the density of interstellar space was kind of sparse,” Ocker said.

Ocker set out to find a running measure of interstellar medium density to fill in the gaps – one that doesn’t depend on the occasional shockwaves propagating out from the Sun. After filtering through Voyager 1’s data, looking for weak but consistent signals, she found a promising candidate. It started to pick up in mid-2017, right around the time of another whistle.

“It’s virtually a single tone,” said Ocker. “And over time, we do hear it change – but the way the frequency moves around tells us how the density is changing.”

Weak but nearly continuous plasma oscillation events – visible as a thin red line in this graphic/tk – connect stronger events in Voyager 1’s Plasma Wave Subsystem data. The image alternates between graphs showing only the strong signals (blue background) and the filtered data showing weaker signals. Credit: NASA/JPL-Caltech/Stella Ocker

Ocker calls the new signal a plasma wave emission, and it, too, appeared to track the density of interstellar space. When the abrupt whistles appeared in the data, the tone of the emission rises and falls with them. The signal also resembles one observed in Earth’s upper atmosphere that’s known to track with the electron density there.

“This is really exciting, because we are able to regularly sample the density over a very long stretch of space, the longest stretch of space that we have so far,” said Ocker. “This provides us with the most complete map of the density and the interstellar medium as seen by Voyager.”

Based on the signal, electron density around Voyager 1 started rising in 2013 and reached its current levels about mid-2015, a roughly 40-fold increase in density. The spacecraft appears to be in a similar density range, with some fluctuations, through the entire dataset they analyzed which ended in early 2020.

Ocker and her colleagues are currently trying to develop a physical model of how the plasma wave emission is produced that will be key to interpreting it. In the meantime, Voyager 1’s Plasma Wave Subsystem keeps sending back data farther and farther from home, where every new discovery has the potential to make us reimagining our home in the cosmos.

For more on this research, read In the Emptiness of Space 14 Billion Miles Away, Voyager I Detects “Hum” From Plasma Waves .

Reference: “Persistent plasma waves in interstellar space detected by Voyager 1” by Stella Koch Ocker, James M. Cordes, Shami Chatterjee, Donald A. Gurnett, William S. Kurth and Steven R. Spangler, 10 May 2021, Nature Astronomy . DOI: 10.1038/s41550-021-01363-7

The Voyager spacecraft were built by NASA’s Jet Propulsion Laboratory, which continues to operate both. JPL is a division of Caltech in Pasadena. The Voyager missions are a part of the NASA Heliophysics System Observatory, sponsored by the Heliophysics Division of the Science Mission Directorate in Washington.

More on SciTechDaily

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Voyager 2 Illuminates Boundary of Interstellar Space 11 Billion Miles From Earth

It’s Official – Voyager 1 Has Entered Interstellar Space

Voyager 2 Probe Enters Interstellar Space, Over 18 Billion Kilometers from Earth

Mysteries abound: nasa studying the edge of the sun’s magnetic bubble, nasa’s interstellar boundary explorer charts 11 years of change to heliosphere.

NASA’s Voyager 1 Explores the Outer Limits of Our Heliosphere

In the Emptiness of Space 14 Billion Miles Away, Voyager I Detects “Hum” From Plasma Waves

106 comments on "hear the eerie sounds of interstellar space captured by nasa’s voyager".

Hope someone loops the sample between the two high pitched spots. From 32 second to 36 second marks. Seem like a great mask for tinnitus pitch around 21 kHz.

Wow! It sure would! My tinnitus is really quite bad, but I almost couldn’t hear it during those few seconds.

Where is the sound?

In the video?

Don’t be a jackass Conrad

I thought there was no sound in space. I also thought nothing not even light can escape a black hole, yet they always report that black holes are emitting Jets of gamma rays and other stuff.

It is a radio wave, which happens to lie on an audible frequency (but else it is a popular presentation nowadays to translate frequency signals to sound).

Perhaps the paper title says it best: “Persistent plasma waves in interstellar space detected by Voyager 1”, The article is dumbing it down – I had to read the then no-paywall paper to understand what they see (and IIRC they find it likeliest that the nearest star is causing the emission, which is exciting).

Nothing comes out of a black hole. The gamma rays you mention are from materials just outside the black hole. Material falling into the black hole are accelerated to high speeds, and they collide with each other creating high temperatures. Those hot materials emit the radiation.

And you beleive all that bs.. lmbo

The only bs I am sure of is the uninformed tinfoil hat nonsense being typed by a few dunderheads hell bent on curing their fear of the unknown.

We will continue to follow the scientific method, you continue to type lmbo over and over like a demented parrot.

Sound cannot travel thru the vaccuum of space

As radio waves, it can.

Space is fake. Nothing can travel though fakery. Lmbo People sure love their space monkey fantasies. There is water above us and the Controllers dam well know this

Radiation can travel in a vacuum. Think of it like this. The suns sends its radiation out to through space, when the radiation hits our atmosphere it is converted and Thea Seth is warm compared to space. Radio waves are radiation. There is no sound if you were in space and the radio waves passed by. There must be something that receive that radiation and convert it to sound. For instance you can walk outside and you will not hear a huge garbled sound of all televisions and all radio stations. Even when you are not in a vacuum you don’t hear the radiation of tv and radio signals. You have to have some device that can “catch” the radiation and convert it into sound like an FM or AM radio station. Only your radio can catch that radiation and convert it into sound. Of course it is a little more to it than that, but hopefully helps your head to wrap around the idea. Radiation needs no medium to travel through, like our conventional sound waves from knocking on a door. Radiation travels through a vacuum.

Omg..were you taught that BS lie in school or is that your own theory?. lmbo

Just had to listen, being a common mortal, and so far away from interstellar space! Another first for NASA’s JPL and I will assume that there are many more pleasant surprises in store for all of us to marvel at. The whistling hum; way-spacey! Enjoy.

My tinnitus is annoying me extremely right now. I’m willing to try anything!

If you are serious about having tinnitus, there are effective treatments. Usually you see an Ears Nose and Throat specialists. Mine got really bad in the 1990s. There were different treatments then, and I imagine more so today. What worked for me was “attenuation therapy”. They give a hearing aid like device that emitted a white noise which covered up the ringing. Eventually, my brain started to tune out the constant white noise. It took a while, but once my brain tuned out the white noise the ringing was tuned out. My quality of life vastly improved. In the beginning they actually put a very tiny microphone into my ear canal to see if there really any noise. There wasn’t, so they new they were dealing with real tinnitus and not a structural deportation. My primary doc kept telling me there was nothing you could do about it. He was wrong. There are doctors who specialize just in tinnitus.

The first ‘blast’of sound of plasma is the initial shock wave; the second is the second is the true sound yet echoing.

Sounds a little agitated.

Humpback whale song

People actually believe this?

I said the same thing..fakery for sure.

And people actually buy this bs as real. Lmbo

It’s remarkable we are still receiving science data from these OLD, relatively primitive machines. They are sending extremely weak signals across billions of miles and we can still hear them. Amazing.

And, of course we hear from the deniers who immediately doubt anything they don’t understand. Surprised they haven’t accidentally fallen off the edge of the Earth.

And you actually beleive it? Lmbo

You call us deniars. I was indoctintated just like you all my life. Programmed. It’s time to come to reality friend. They have been deceiving us. We are not a spinning marble with water miraculously sticking to us like glue. Ridiculous in itself. Goes against your senses anyway. There is water above us and they dam well know it. They cannot and will not ever get past the firmament. You have been programmed all your life to beleive this and most will not research past their noses. They like being fooled

Indeed. It’s amazing they leave the house with pants on quite honestly.

You make jokes about the edge of the earth…lol And there is an obvious ice wall around us. Of course you will say that’s not so. But it dam well is. And the leaders of the world know it. The Antarctic treaty. Where you and I cannot go. But you will beleive something much more fairly talish like a spinning marble rotating a 1000 mph miraculously holding water to while moving 67,000 mph through space..lmbo fairy tail much

Yeah that’s called gravity school boy ,,plus untill you get on a plane and flys around the earth dont talk your stupid ideals …that’s all u have is a ideal to run with

And you beleivethe bs… dam you people are indoctrinated and or programmed. Think for yourself and use common sense

Science is about testing hypotheses and changing those hypotheses if the data doesn’t support it. So prove it. Go find your ice wall. Don’t come back until you do.

Just go to the Antarctic. That’s your Ice wall..go north south east or west and you will run into it. You beleive in spinning marble but an ice wall in somehow out of the question. I laugh at you people There is no OUTER SPACE. You have been fooled.

Sounded ok until the end bit then it went high pitch I squinted too but like other comments we are not spinning on a ball it tells you in Genesis job and few more scriptures they only brought a globe into our heads cuz of copernicus but ancient tribes allsaid and showed earth was flat.anyway no stars are under earth no rain can fall up!!

When your actually out of grade school and have a clue what your saying…try putting anything like water or a ball of dirt ina vacuum and wait and watch how gravity forces all. Matter into it’s most simist form and that’s a ball just like the moon and sun you dummy

Joe keep up the desperate antics that make no dam sense. The earth is not a spinning magic marble and gravity is man made bulls#!t lie

I know you did not just say that bunch of BS…did you? Common sense should prevail. The world is so dumbed down by the lies/programming of these luciferians that cant see two feet in front of them. You included. We laugh at you. You are the ones in the fairytale.

I was talking to you Joe

In space nobody can hear you scream “bulls#!t’

It’s turtles all the way down Pfft. Fools.

I can’t believe you kids—gravity holds water to this blue & green ball. And no, the Earth is not flat. THAT is ridiculous

Oh. You mean that made up bunch garbage to fit their scientific theory? Gravity is joke. Pure fantasy. And you accuse commonsense of being crazy. A flat plain just sounds so crazy…lmbo. But magic gravity sounds so logical…lmbo Get out of your programming

Ya know all that crap about nothing can escape a black hole is only a theory plus how do they know if atoms or light photons are jus bouncing off the event HORIZON and. Your so called hole is actually some giant natural collider that creates new particles out of old stuff!

Oh my goodness Joe. You beleive in theories? Lmbo And Accuse us of being in grade school. Can you please stop repeating like a parrot what the liars taught you in school. Think for yourself and look up in the sky and start researching yourself. You wont. Cause you like being spoonfed BS.

Seems like an odd way to lie about something (intricate, detailed, boring, scientific terminology)… To no real end goal, as the ‘stories’ of space don’t ask or persuade me to any specific task.

People that actually deny science never seem to have any method to prove their own beliefs… I guess that’s because they would need to provide some type of evidence, maybe with some odd method, maybe call it (schnience)

You mean psuedoscience

Nice Masonic pose in your picture

JY you can go to Antarctica. It not off limits. Those countries signed that treaty to prevent military bases from being build. The world doesn’t have some weird water ring around it? Lmao. Where the hell did you gear that? History channel (Ancient Aliens) Or do you study scientology? World is flat?

Quick question? What does the science community gain by saying Voyager is picking up radiation waves? Nothing. It makes no difference to our everyday lives. What does the (plasma wave subsystem antennas) do on Voyager? What’s your degree in? Stop acting like everything is a conspiracy theory. You know nothing and ONLY follow conspiracy theories. Attach others when they challenge you. JY you are lame

You are so full of sh*t..no you cannot go to the Antarctic. Only on tours…lmbo Where they say you can go…you programmed fool…

You are a programmed fool…lmbo They gain control by keeping the masses dumbed down. You lame excuse for a supposed educated person. Lmbo I am so sick and tired of trying to wake your asses up to these luciferian controllers. With their satanic ball earth. You cannot go freely to the Antarctic you idiot. You can only tour where they will let you. Lmbo Dam you people are dumb as rocks and clueless. Try going there by yourself you fool and walking around. Lmbo.

To boldly go for no man has gone before… One big leap for men one giant leap for all…..

Lmao sound in a supposed vacuum. If you buy into this they have a bridge to sell you

JY is a hilarious troll so many people falling into the trap.

No…I am awake. You are either the real troll or part a programmed fool.

These people like JY that claim this is fake are scary. They are seriously messed up and need YEARS of therapy. YEARS. Amazing still they use GPS, Watch TV, and enjoy the internet never realizing that is because 9f SATELLITES in SPACE. Wow special kind of ignorant.

And we wonder why the WORLD laughs at us? We wonder how losers like Taylor Greene and Trump get elected? It’s because of simple minded ignorance like this guy. And of the Earth was flat, how would a plane fly die East and end up on the West Coast? Or are airplanes now a hoax and the devil?

You need help.

I dont watch TV and ththe internet has nothing to do satellites. It has everything to do with cell tower and under water cables. You are so smart. Let see. The earth is spinning 1000 mph. The satellite TV connects to the satellite moving 17,000 mph… somehow stays connected to it when it moves to the other side if the world. Lol…you people are the crazy ones to beleive the bulls#!t. Use your dam common sense. Cell towers people. Not satellites. They are lieing to us. I am awake to the scam. And by the way. GOD is real. And you better wake up. The devil and real and he is fooling you. And you beleive the opposite of way you should. Common sense tells you we are stable and not moving. Wow. What a bunch of programmed fools.

I dont watch TV and ththe internet has nothing to do satellites. It has everything to do with cell tower and under water cables. You are so smart. Let see. The earth is spinning 1000 mph. The satellite TV connects to the satellite moving 17,000 mph… somehow stays connected to it when it moves to the other side if the world. Lol…you people are the crazy ones to beleive the bulls#!t. Use your dam common sense. Cell towers people. Not satellites. They are lieing to us. I am awake to the scam. And by the way. GOD is real. And you better wake up. And you beleive the opposite of way you should. Common sense tells you we are stable and not moving. Wow. What a bunch of programmed fools.

The amount of anti-science people on this page is astounding. JY is the moon flat? Is Mars flat too? The Earth is a globe. People can and do visit Antarctica on their own. The only thing stopping you as an individual is money. Use enough amd take whatever supplies you will need and book the ship time. The Earth is round. Proven time and time again using different methods of science and math. Not one of you flat earth people can back up your claims in legitimate math or science. Curvature of the earth is a real thing. Plasma particles being translated into audio is rather simple. Stars do put off radio waves which can be translated into audible sounds as well.

It has not been proven time and time again. That is nothing but a lie. It gets so tiring with people like you making comments like it been proven that the earth is spinning 1000 mph whirling 67,000 mph through infinite nothing. That is such a lie. It’s all theory and make up bulls#!t. That’s your may of continuing the programming of their minds. It’s pure programming and indoctrination.

Mars is really just a desert on earth you programmed little boy.

You sure believe alot BS. Dont you? Lmbo How in the world do you people let them feed you such bull*** is beyond me.. You believe their fake Masonic math lol.. Cant even get real pictures of Earth. All CGI. And you people beleive these liars. Curvature has not been proven at all. Its smoke and mirrors. Fish eyed lenses. And if you calculate the math they use it doesn’t even add up anyway.lol All I see I flat land. No dam curvature at all. The dam problem is the programming of weak minds that think they are wise. You have no wisdom at all. You are a fed machine that only follows instructions with any reasoning or common sense

I’m glad you enjoyed the song. Now get back to work!

Idiots!!!!!

TY, you sound like the only one that is programmed. So everything to you is a hoax? Guess there is no sun either? I mean, how could a ball of fire remain in a circle? Or is the sun flat too? Your brainwashed. Good luck with your fantasy.

You poor brainwashed soul. I wish I could wake you guys up. But it hopeless for the majority of this programmed world

TY. Who programmed you ? You are clueless. Never take a long walk, you’ll fall off. But where? There’s nothing there, right? So the Sun must be flat too. Or are we just someone’s science experiment?

I have common sense…lol No one programmed me….a spinning marble hurdling through infinite nothing moving at ungodly speeds through the vacuum of space..lmbo ridiculous. That makes so much more sense them a flare non moving plain. I can see with my own eyes we are not moving. You are programmed

The Sun and moon are both lights. They give off there own light. But you beleive this stupid made up bs that the sun light reflects off the moon. Totally ridiculous. But then the programmed minds beleive anything. Once again common sense should prevail

If light can travel through space, I can’t see why sounds can also. If anything can I believe sounds can, but die off at some point.

Be sure that your thinking doesnt fall flat. The world Is round.Some things cant be fully shared until they are more in the known than guessing. But in reality,unless you sitting in the craft we have to trust the judgement of those interpreting the data. Give them a break at least some one on the blue marble is thinking outside The Box, or in this case outside the Bubble.

Sorry buddy the blue marble is a satanic lie. Your senses tell you something else. Look up in the sky. We are not moving. Foolishness.

Sorry my mistake after doing some actual research the earth is round and space does exist

Nice try the fake JY…

Simply fascinating!

JY was more interesting than the initial article. I feel I that I really want to learn more about his logic and his world. Feels like we are all different beings living in the same space time but somehow in different brain realities.

My life is pretty boring with normal ppl …I ve never heard in my life someone refering the moon and sun as light…still they are round. When I was a kid I enjoyed watching the boats at see and after a while they disappear. I have been wondering about that since then I am sure the real JY will tell me why everyone can see boats disappear once the go far away from the sea. Usually water is not round so why how do boats disappear on the horizon??

Read your Bible science man. Its says the moon and Sun are both lights. Makes perfect sense to me. You expect me to beleive you have never heard that before? Lmbo Your pseudoscience is your god/religon. All fakery and made up bs that makes no logical sense but people buy it as real. Your senses tell you something totally different science man. You can clearly see we are not moving and you can clearly see water finds its level. So go crawl back under your rock and continue your brainwashing.

Btw Science man. You can easily use a P900 camera and pull the boat right back into view. So if it went over the Horizon or supposed fake curve then you would not be able to bring it back it to view but you can. Btw. Have you ever heard of perspective? Science fiction people only use it when it benefits their cause. The earth is a Plain with nice mountains and valleys. Its circular just like the Bible says. Not a spinning hurdling water ball. Lmbo

Yet you beleive in a spinning water ball…moving though infinite nothing at ungodly speeds while spinning 1000 mph. And I beleive in MAGIC…lmbo Woe to the hypocrites of pseudoscience bs.

Whoever this jy is, you are a credit to stupidity. Since you dont understand science at any level, please stop wasting everyone’s time by showing your infinite ignorance and get back to your xbox and blunts like a good little boy. We are all privileged to be witness to a connection beyond our solar domain. P.S. jy, that means our solar system.

You mean credit to common sense and logic. Thank you very much

JY I have red the Bible a few times and a few versions too. Which one are u reading?

Its full of nice stories like people that can live inside a fish. A dude that walks on water. Women go gets converted into a statue. Cities that crumble because a magical box. I use to believe in all this stuff cause I was a kid and was living in a city that every one believe it… But I also believed in Santa Claus and unicorns and Peter Pan…we also have books for those stories.

All books made. Written and reprinted by men.

Bible is a bit outdated cause that God allows slavery..and violence. It also seems to favor men over women so not really a team player but really like the first miracle… Multiple the wine… That’s a strong message out all possible things that could be done to fix this world he choses as his first miracle to produce more wine… Each time someone says something when I am drinking…I remind them that wine is approved by God. Not only approved but he wanted everyone to drink more otherwise why produce more? That is a strong message to send to the humans and for eternity.

I don’t know how hell looks like but I am sure there must be good wine in heaven 🙂

Well when I was a kid red as a kid…I walked like a kid and I believed magical stories like Santa…but eventually I grew up and learn to read other books and think for myself and I don’t need to believe in Santa anymore to enjoy Christmas or to believe in unicorns to enjoy movies and stories… neither I need Bibles to live my life in a respectful and healthy way. And I don’t need heaven or hell to understand what is constructive or destructive. It’s nice to see that some ppl still believe in magic even as adults…I wonder if u write letters to Santa and think there’s a magical world waiting for your somewhere…but you need to send 200 000 comments on the internets before you’re allowed in??

Wait a minute Mr. 666…Who believes in magic? A spinning marble hurdling through infinite nothing while water sticks to it seems a little more like magic than a flat non moving plain. Lmbo Where you can observe with your own eyes that we are spinning 1000mph. Lmbo…BTW Santa Claus is really Satan Claus. Unscramble the word. Your Masonic 666 brothers made up the satanic ball earth and Santa/satan claus. Either you are asleep and indoctrinated/programmed like 99 percent of the world or your are a Masonic troll. There is a God brother. It’s funny how you believe Faith all bulls#!t fed to you by the liars but somehow God and a creator is crazy to you…Wow. It’s obvious there is a Creator. Intelligent design all around you…A fool beleives in his own heart that there is not a God. Now wake up before die and face judgment.

You can believe or not believe in God. You have a free will. Take your chances. Forfeiting your soul for an eternity is forever my friend. A fool beleives in his own that there is not a God. Creation is in your face. To act like you dont see it is dumb.

JY I don’t need to believe in any God to find a purpose and be happy and don’t care about paradises or hell I have enough with one.

Ppl that need to believe in God’s are weak. They can’t face reality just like kids …they need Santa…some ppl need God’s to stay stable and live through reality. You were endoctrinated by your mommy n now that endoctrination makes you feel good. It is ok not being able to go against what mommy told you. That would mean pain. Just like facing reality that u will never see ppl that died is painful. Painful like you will also die like everyone else and nobody will care cause we’re only dust in the wind my friend. So which story is the painful one? Face the painful reality takes courage and one needs to be strong to accept it. Thinking that there’s a magical dude that will take care of all my issues and give me immortality is very easy but weak. Makes you feel good but those are just feelings. I you had more money you could buy a boat and sail around the world and see it for yourself. If u were not poor you could buy a jet and drive around and see it for yourself. If I could I would send you for a trip to space so u could see it for yourself but I don’t have 20 million yet. And you would probably refuse to go because that would mean discovering of the painful reality.

It is easier and more pleasant for me to believe in God’s than it is for u to face the painful reality. You will die playing a god and I will die reading where voyager 1 and 2 are by that time and will be thinking…what a nice ride they had and one day they will crash into a planet or a black hole. Eventually everything dies and no one comes back. But u are free to believe otherwise if that makes you feel good. But remember…those are just feelings 🙂

Die in your Sin Mr 666. Its your soul. You wont be talking like this when you are standing before the Almighty.

The earth is not a spinning water ball friend. Regardless of what you think. They are lying to us. Learn how the Elite communicate worldwide. Learn signs and symbols and numbers. Its how they speak. Once you learn their language. It’s clear what is really going on here. Stay blind and decieved. This world is literally ran on signs symbols and numerolgy. That’s also in your face. But you will never see it. You like being controlled. The Elite of decievers are at the top of the pyramid. They bottom are just cattle. Good luck with you programming.

Jy you need help bro space is not fake you have to be dumb as sh*t to believe that, space is real, asteriods, there is 100% factual science, nearly 80 years of evidence by experts an scientist who most of which btw dont work for the government an whos only interest is to learn about the things around our round planet, you know what they call space, your theory has no evidence or facts or findings to back up what you say. I recommend reading a book or two do your own research space is real, planets are real, and our earth is not flat it is round. Eduacate yourself just a tip

Boy you folks dont give up. Space is FAKE. EVERYTHING NASA gives you is smoke and mirrors. I was indoctintated just like you space monkeys. I have done plenty of research on my own to see that NASA is lying to us along with all the fake space agencies around the world. Water always finds it level. I don’t give a crap what scientific rebuttal you come up with. One more time. WATER ALWAYS FINDS ITS LEVEL. The Sun and moon or local. It’s obvious to anyone awake and willing to stop being programmed by these luciferians that control the world system. I always see flat land. Gravity is impossible if you actually just use your dam common sense God gave you. It’s made up bulls#!t to fit their scientific theory. That’s all it is. You are so indoctrinated you take everthing they tell you as truth. All they give us is CGI. They lost the technology to go back to the Moon but they can travel millions of miles further to Mars…lmbo Wake up blind fools. Its funny how they have the ability to control a rover millions of miles away though a computer and when it breaks down it fixes itself.. lmbo A super machine..lol

You are programmed. You repeat like a parrot what you been fed all fed all your life.

I almost missed the video in the flood of other ads on the page.

I hope you know that sound is something like animal or humanoid being Istanbul not space sounds but it the could pin point the exact location or close by with the hubble they might find a planet with life, on it the question is thier someone thier , I recognize the sound that of a cry out

Your kidding right? Lmbo

This guy with the ice wall surrounding the earth is funny I flew around the earth it’s round and not surrounded by an ice wall.

I am sure you have.lmbo Nothing any of you programmed sheep say will ever change the fact that we do lot live on a spinning magic water ball.

Magic ice walls and magic souls that live forever floating around sounds retarded. Maybe JY is just a retarded that was brainwashed by his religious parents. Poor person…

You mean magic spinning marble moving through infinite nothing at 67,000 mph…lmbo Sound a little more like fantasy than a non moving plain. Boy you folks have logic backwards….🤣🤣🤣🤣

Keep mocking God. How do you think you got here you very foolish person? Intelligence design all around you and you choose to beleive in magic. Wow. All this came from noth in nothing. Now that’s magic.

I think NASA is bitch n fags all lairs they could go to hell where they belong

Well they are all liars and freemason/luciferians.

JY I haven’t laughed so hard in ages, thank you so much. I’m stunned you hang around on these pages to embarrass yourself, your preaching should be on the stage or street corner it’s hilarious 😆🤣😂😄! Why are you even reading articles like this if you don’t believe? Lmao! I can’t stop laughing 😆🤣😂😭! I guess the dinosaurs are also a conspiracy!? Ice walls 🤣🤣🤣🤣🤣, water in the sky🤣🤣😂, I can’t take anymore my sides are aching!!! Brilliant

Putting little laughing emojis is not going to change the fact that you are a brainwashed troll. Rovers and helicopters that fix themselves and fly by remote control millions of miles away…now that deserves an emoji.🤣🤣🤣🤣🤣

If JY was for real… I would pay to see this guy and his conception of universe and earth it is so far fetched and originally retarded like if he had missed the last 200 years of science LoL I ended here cause I want to read about science and space but I wonder how did JY ended here .. is he trying to convert ppl ? LoL 😂 I wonder how many people he has converted so far…in the internets lol all these lost internet souls LoL 😂

Jy is loopy

ok lets carry the discussion to another level by thinking about speed of think… i gues it will overcome the light speed obviously and ppl discussing abt illusions and/or reality as if anyone able to understand what they are we call ourselves as a human being by compare to other souls but how abt if we are also hoax dream in the dream or just a echoes of the some creature which exist at zillion light years ..conclusion GOD exist ! if not pls advise what is a spirit and how its created by who and its appearance…. we are enjoying the message comes from the location where its out of our dimensions and we are the so luckiest ones that can hear it with a single click.there may be another dimensions which control the earth but eventually all the beings are subject to return to the Creator which we call GOD .

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The Voyager Golden Record

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You Can Now Listen to the Voyager Golden Record Online

The sounds of Earth, launched into space in the 1970s, now available on Soundcloud.

Voyagers 1 and 2 both carry a Golden Record, intended to play the sounds of our planet for any advanced extraterrestrials who might one day find a lonely spacecraft and wonder what the people who built it were like. The sound files—which include animals, vehicles, music, and more—were already available individually on the NASA Voyager website . Now that they're on Soundcloud, though, you can enjoy them as the full playlist they were intended to be:

Source: Popular Science

Andrew's from Nebraska. His work has also appeared in Discover, The Awl, Scientific American, Mental Floss, Playboy, and elsewhere. He lives in Brooklyn with two cats and a snake.

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Voyager 1 Has Gone Silent in Deep Space

How Voyager 1 recorded noises when there's no sound in interstellar space

Beyond the border of interstellar space, the distant Voyager 1 spacecraft called back to Earth earlier this year with noises from its new environment. It's true that the void of space does not carry sound — there's no gas or other substance to transmit the waves — but the signal Voyager detected can be played back at frequencies the human ear can understand.

NASA announced in September that Voyager 1 had left the heliosphere in August 2012. The heliosphere is a sheath of magnetic influence that emanates from the sun and expands through a stream of charged particles called the solar wind.

At the press conference, Don Gurnett, the principal investigator for Voyager 1 's plasma wave science instrument, demonstrated a series of sounds the instrument had picked up.

"Strictly speaking, the plasma wave instrument does not detect sound. Instead, it senses waves of electrons in the ionized gas or 'plasma' that Voyager travels through," NASA stated in a statement. These waves, however, do take place at frequencies that humans can detect.

"We can play the data through a loudspeaker and listen," Gurnett, a physics professor at the University of Iowa, said in the statement. "The pitch and frequency tell us about the density of gas surrounding the spacecraft." [ Hear What Voyager 1 Detected ]

Within the heliosphere, the sounds had a frequency of about 300 Hz. Once Voyager left the scene, the frequency jumped higher, to between 2 and 3 kHz, "corresponding to denser gas in the interstellar medium," according to the NASA release.

There have been at least two verified instances of these tones: October to November 2012, and April to May 2013. Both occurred after huge coronal mass ejections (material from the sun) bumped up plasma activity around Voyager 1. There was a lag before scientists discovered the recordings because the data is only played back every three to six months, NASA said, and more time is required to interpret the results.

Gurnett further speculated that "shock fronts" from beyond the solar system could be tearing through interstellar space and disturbing the plasma surrounding Voyager 1. He will be listening for any evidence of this activity in future recordings from humanity's furthest spacecraft, he said.

Follow Elizabeth Howell @howellspace , or Space.com @Spacedotcom . We're also on Facebook and Google+ . Original article on Space.com.

• Voyager 1 Records 'Sounds' From Interstellar Space | Video
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Voyager 1 Probe Captures 1st-Ever Sounds of Interstellar Space (Video)

Thanks to NASA's far-flung Voyager 1 spacecraft, now exploring the final frontier beyond our solar system, humanity can tune into the sounds of interstellar space.

Scientists announced today (Sept. 12) that Voyager 1 left the solar system in August 2012 after 35 years of spaceflight, making it the first craft ever to reach interstellar space. No other manmade object has ever travelled so far away from its home planet.

To mark the occasion, NASA unveiled the first  Voyager 1 recording of the sound of interstellar space , offering the probe's strange, otherwordly take on its new frontier. The sounds are produced by the vibration of dense plasma, or ionized gas; they were captured by the probe's plasma wave instrument, NASA officials wrote in a video description. [ Voyager 1's Journey to Interstellar Space: A Photo Tour ]

"When you hear this recording, please recognize that this is an historic event. It's the first time that we've ever made a recording of sounds in interstellar space," Don Gurnett, principle investigator for the Voyager plasma wave investigation, said in a press conference today.

Researchers used the plasma data to infer that Voyager 1 first came into contact with the interstellar medium, effectively taking humanity between the stars, on or around Aug. 25, 2012.

"There were two times the instrument heard these vibrations: October to November 2012 and April to May 2013," NASA officials wrote. "Scientists noticed that each occurrence involved a rising tone. The dashed line indicates that the rising tones follow the same slope. This means a continuously increasing density."

Voyager 1's plasma sensor broke in 1980, so scientists had to get creative, and a little lucky, to figure this out. A massive solar eruption in March 2012 arrived at the location of Voyager 1 about 13 months later, making the plasma around the probe vibrate, NASA officials said.

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That vibration helped researchers understand the density of the plasma, determining that it was 40 times more dense than measurements taken in the outer layer of the heliosphere, the bubble of charged particles and magnetic fields that the sun puffs out around itself.

The observed density matched up very well with what researchers expected to find in interstellar space.

"Now that we have new, key data, we believe this is mankind's historic leap into interstellar space," Ed Stone, Voyager project scientist based at the California Institute of Technology, Pasadena, Calif., said in a statement. "The Voyager team needed time to analyze those observations and make sense of them. But we can now answer the question we've all been asking — 'Are we there yet?' Yes, we are."

Voyager 1 launched on Sept. 5, 1977, about two weeks after its twin Voyager 2. The two spacecraft made it through their "grand tour" of the solar system, taking close-up looks at the Jupiter, Saturn, Uranus and Neptune systems. Their original mission ended in 1989, but the probes soldiered on, streaking through the unexplored regions at the outer reaches of the solar system.

The Voyager team still communicates with the two spacecraft every day, but the probes' extreme distances pose a challenge. At the speed of light, it takes about 17 hours for a message to reach Earth from Voyager 1, which is currently about 12 billion miles (19 billion kilometers) from the sun.

Follow Miriam Kramer @mirikramer and Google+ . Follow us @Spacedotcom , Facebook and Google+ . Original article on  SPACE.com.

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

Miriam Kramer joined Space.com as a Staff Writer in December 2012. Since then, she has floated in weightlessness on a zero-gravity flight, felt the pull of 4-Gs in a trainer aircraft and watched rockets soar into space from Florida and Virginia. She also served as Space.com's lead space entertainment reporter, and enjoys all aspects of space news, astronomy and commercial spaceflight.  Miriam has also presented space stories during live interviews with Fox News and other TV and radio outlets. She originally hails from Knoxville, Tennessee where she and her family would take trips to dark spots on the outskirts of town to watch meteor showers every year. She loves to travel and one day hopes to see the northern lights in person. Miriam is currently a space reporter with Axios, writing the Axios Space newsletter. You can follow Miriam on Twitter.

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Good news from Voyager 1, which is now out past the edge of the solar system

Nell Greenfieldboyce

In mid-November, Voyager 1 suffered a glitch, and it's messages stopped making sense. But the NASA probe is once again sending messages to Earth that make sense.

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Decoding Voyager 1

Today is the 44th anniversary of the launch of Voyager 1 , so I want to celebrate by showing how to decode the Voyager 1 telemetry signal using GNU Radio and some Python. I will use a recording that was done back in 30 December 2015 with the Green Bank Telescope in the context of the Breakthrough Listen project. Most of the data from this project is open data and can be accessed through this portal .

In contrast to other posts about deep space probes in this blog, which are of a very specialized nature, I will try to keep this post accessible to a wider audience by giving more details about the basics. Those interested in learning further can refer to the workshop “ Decoding Interplanetary Spacecraft ” that I gave in GRCon 2020 , and also take a look at other posts in this blog.

Handling the raw recording

The direct link to the 16 GB recording that I will use is this one . This recording is in GUPPI fomat , which is a format that stores the raw IQ output (voltage mode) from a filter bank. This kind of file is often processed to transform it to make it easier to use for a particular application and reduce the data size. For instance, in this Jupyter notebook from Breakthrough Listen, a file in filterbank format produced from this data is used to plot the signal spectrum. The filterbank format is essentially some kind of high-resolution waterfall data (power versus time-frequency), and it is often used in SETI (this recording of Voyager 1 was made to test SETI algorithms). Here we need to use the raw IQ data in the GUPPI file to process the digital modulation. I also used this GUPPI file in a post from a few years ago about the Voyager 1 polarization .

The data in the GUPPI file is divided in 64 frequency channels, each of them having a bandwidth of 2.9296875 MHz, which gives a total observing bandwidth of 187.5 MHz (the division by 64 explains the rather peculiar sample rate of each individual channel). The centre frequency of the observation is 8493.75 MHz, and the Voyager-1 signal can be found at 8420.216454 MHz.

In comparison to the large bandwidth observed in this recording, the Voyager-1 signal is tiny. It fits in less than 100 kHz. Luckily, it is contained entirely in one of the 64 channels of the GUPPI file, which simplifies the processing. We can use this single channel and throw away the rest, instead of having to glue two adjacent channels to produce a single stream of IQ data.

The IQ data in each channel is stored as 8-bit integers. The only quirk is that the frequency axis is inverted in each channel, so the sign of Q needs to be flipped to correct this (another possibility is to swap I and Q). In radio astronomy it is very common to quantize with a low number of bits, such as 4 bits or 2 bits, since the signals typically have low SNR.

The file contains the two circular polarization channels: LHCP and RHCP. Since the Voyager-1 signal is LHCP, we will only use that channel. The recording is rather short. Its duration is only 22.57 seconds.

All these technical details about the file format are contained in the GUPPI file itself. This file format has a header with metadata in ASCII, then a block with binary data, then another ASCII header followed by more binary data, and so on. The first header contains the following:

To process this file in GNU Radio, I use an Embedded Python Block that reads data from one of the channels of the file. The code in this block is based on the Python code I used in my older post , which in turn is based on code from blimpy , which is a Python tool used by Breakthrough Listen to manipulate file formats. I originally made this Embedded Python Block for a session with the Berkeley SETI Research Center REU summer students this year. In that session I used this block to show the students how to use GNU Radio to display the spectrum of the signal in different ways.

This GUPPI File Source block is shown below. It is something very crude, as it has almost all the parameters hardcoded, including the path to the GUPPI file. It has a “frequency” parameter that it is used to select the frequency channel that the file source will use. It will only use the channel that contains that particular frequency. Its two output ports give each of the two polarization channels as complex floating point data.

This GUPPI File Source block can be used to prepare a reduced file that only contains the LHCP polarization of the frequency channel in which the Voyager 1 signal is present. The flowgraph shown below performs the reduction. Note that neither the GUPPI File Source nor the Complex To IChar are changing the scale of the samples, so we end up with the same 8-bit samples that were present in the GUPPI file.

The advantage of performing this reduction is that the resulting file has a size of only 127 MB. This reduced file can be downloaded here , and is the file that will be used in the rest of this post.

A brief look at the modulation

Even with Green Bank’s 100 metre telescope, the Voyager 1 signal is weak enough that it is difficult to detect in the 2.9296875 MHz channel from the GUPPI file unless a large FFT size and long integrations are used. The material from my Breakthrough Listen REU session shows how to do so.

If we know exactly at which frequency the Voyager 1 signal is located, it is easier to use the Frequency Xlating FIR Filter block to move the signal to baseband and decimate by a factor of 35, giving a sample rate of ~83.7 kHz. This allows us to see the signal more easily with a modest FFT size of 4096 points. The GNU Radio flowgraph used to plot the spectrum with this technique is shown here.

In the resulting plot we can see the residual carrier of the signal as a strong and very thin peak in the middle and the data subcarriers as thin humps at ±22.5 kHz from the carrier.

This kind of modulation is used very frequently to transmit low rate telemetry from deep space probes. Its technical name is PCM/PSK/PM (see this document ) and it is a residual carrier phase modulation. People familiar with my posts about deep space probes might recognise that Tianwen-1 , Chang’e 5 , and many others I haven’t studied in detail also use this kind of modulation.

A substantial amount of the transmitted power is spent in the carrier, which is the very thin, unmodulated line we see in the middle. This relatively strong residual carrier allows the people on ground to detect the signal even if there are problems that cause it to be much weaker than expected, to have a reference to track the phase of the signal (which is important at these microwave frequencies), and to measure Doppler very accurately, which is used to help determine the trajectory of the spacecraft.

The rest of the transmitted power is spent in sending the data, which is modulated into subcarriers at both sides of the carrier (in this case at ±22.5 kHz). The data is PSK-modulated onto these subcarriers, so by looking at the width of the subcarriers we can get an approximate idea of the data rate. In this case the subcarriers are thin: around 300 Hz wide or so, since the data rate is not very high. Since Voyager 1 is extremely far from Earth, it typically uses rather low data rates so that it can be decoded with one 70 metre or several 34 metre antennas of the NASA DSN .

The separation between the data subcarriers and the carrier is given by the subcarrier frequency (22.5 kHz here). The purpose of separating the subcarriers is to prevent the data modulation from interfering with the phase tracking of the carrier. Often, a larger separation than strictly necessary is used. The gap between the data subcarriers and the carrier is sometimes used to retransmit sequential ranging tones or telecommand feed-through (which consists in relaying the telecommand signal back to Earth so that people can check that the spacecraft receives it with enough quality).

The figure below shows a better view of the spectrum of the Voyager 1 signal. It has been obtained by using an FFT size of 4096 points (~20 Hz resolution) and averaging across all the recording length.

Carrier tracking

The first step in processing this signal is to track the residual carrier, in order to estimate and correct for the Doppler and phase offset of the signal. This is done with a PLL . The figure below shows the part of the GNU Radio flowgraph corresponding to the PLL. Since the PLL expects a signal of amplitude one, we use the RMS AGC block from gr-satellites to normalize the signal amplitude.

A small loop bandwidth should be used for best results (less tracking jitter) in the PLL. If the bandwidth is set too low, the loop will not lock, though. Here a bandwidth of 10 Hz is used. Note that the units of the loop bandwidth parameter in the PLL Carrier Tracking block are radians per sample rather than Hz.

At the output of the PLL, the real part of the signal contains the suppressed carrier and the imaginary part contains most of the power of the data sidebands, due to how phase modulation works. This can be seen in the figure below, which shows the real part in blue and the imaginary part in red.

Data demodulation

Usually, the data would be demodulated by synchronizing to the symbol clock with the Symbol Sync block and tracking the subcarrier with a Costas Loop. However, these loops take some time to lock, specially when low bandwidths are used, which is important to deal with weaker signals. Since the recording is only 22.57 seconds long, we will do an open loop demodulation in Python adjusting by hand some of the parameters. This will allow us to demodulate all the data with good performance.

First we use GNU Radio to move the data sideband from 22.5 kHz down to 0 Hz. Note that now the signal is real, being the imaginary part of the output of the PLL, so the spectrum is symmetric. By performing downconversion we obtain a complex IQ signal again in which the data modulation looks like BPSK. Since the data sideband is narrow, we can low pass filter and decimate. All these steps can be accomplished at once with the Frequency Xlating FIR Filter block in GNU Radio. The flowgraph to do so is shown below. We take the imaginary part of the output of the PLL, and decimate by 50 while filtering and downconverting the data subcarrier. The output is saved to a file which is later processed in Python.

We load up the file in Python and plot the spectrum using NumPy and Matplotlib (the code is provided in a Jupyter notebook at the end of the post). We get the figure below. At ±350 Hz we have the cut-off of the filter used in the Frequency Xlating FIR filter. We could have used a higher cut-off frequency if we just wanted to prevent aliasing when decimating, but by adjusting the cut-off to be just slightly larger than the signal bandwidth, we discard a good portion of the noise.

The data signal is actually the hump of a few dB between -240 Hz and 240 Hz. There are two tones at the edges of the signal. The reason for this will be explained later.

The next step is to remove the residual subcarrier frequency and phase. We have already subtracted the nominal 22.5 kHz subcarrier, but there is still a small residual frequency due to Doppler and different clocks at the transmitter and receiver. This residual frequency is present as the suppressed carrier of the BPSK signal we are dealing with. The trick to recover the suppressed carrier is to square the signal (raise it to the power two). This reveals a tone whose frequency is twice the suppressed carrier frequency, basically because it removes the BPSK modulation. The reason behind it is that 1²=(-1)²=1. The figure below shows the resulting spectrum. We see that a strong tone has appeared near 0 Hz.

Now we can low pass filter the central tone to remove much of the noise and measure its phase. Dividing the phase by two (after unwrapping) we obtain the phase of the residual subcarrier. We can use it to remove the residual subcarrier. Then we should should obtain the BPSK signal in the real part, together with noise. In the imaginary part we should get only noise. This is shown in the figure below.

The real part (or I, for in-phase) is shown in blue, while the imaginary part (or Q, for quadrature) is shown in orange. The amplitude of I is somewhat larger than the amplitude of Q due to the presence of the BPSK signal in the I component. The SNR of the signal is rather low, but if it was higher, the amplitude difference between I and Q would be larger.

The plot above indicates that our removal of the subcarrier has been successful, since otherwise the phase of the BPSK signal would rotate and we would see the same amplitude in I and Q. The next step is to recover the symbol clock and demodulate the symbols. For that, we first need to know the symbol rate or baudrate.

The trick to find the baudrate is to take the signal (here we can take the real part after removing the subcarrier) and multiply it against the same signal delayed one sample. Then we plot the spectrum of the result. What we see is quite similar to the spectrum of the square of the signal we did before. Here the presence of tones at ±320 Hz indicates that the symbol rate is 320 baud.

With this knowledge, we can align the sample clock by hand. At the sample rate we are using there are approximately 5.231 samples per symbol. First we run the signal through a moving average of 5 samples in order to add up most of the power in each symbol. We see the result in the figure below, where individual samples have been marked with a dot. Even though the signal is noisy, we can recognise the bits as the positive (bit value 1) and negative (bit value 0) peaks.

Our goal is to take one out of every 5.231 samples in such a way that we are aligned to the peaks of the signal, which correspond to the optimal sampling instants. The thing we can vary is to slide our choice of sampling instants forwards or backwards in time. This corresponds to trying to find the phase of the symbol clock. We also account for a small deviation from the nominal symbol rate of 320 baud. After fiddling for a little with the parameters, we obtain the figure below. We have also normalized the signal to unit amplitude. We can now see that most of the values cluster around +1 or -1. There are some values around 0 which will give symbol errors, but all in all the signal quality is not so bad.

We can also plot the constellation, which shows all the symbols in the complex plane (remember that the BPSK signal was present in the real part, but we also had the imaginary part, which only contained noise). We see two areas where the symbols concentrate, corresponding to the bits 1 and 0.

This finishes the data demodulation.

Viterbi decoding

The Voyager probes use the typical k=7, r=1/2 convolutional code as a forward error correction method. In fact they were among the first spacecraft to use this code. A Viterbi decoder can be used to correct for bit errors and obtain the original message.

The convolutional code produces a pair of bits for each input bit. These two bits are transmitted sequentially. At the receiver, we need to pair the two bits again. There are two possible ways to do this, given by the two possible arrangements of drawing lines between symbols in a stream in order to divide them up in pairs.

There are different techniques to decide which is the correct pairing. A simple but effective way to do this consists in running the Viterbi decoder separately for each of the two possibilities, encode back with the convolutional encoder each of the two outputs, and compare them with the received data to count the number of bit errors. The correct choice will give a relatively low number of bit errors.

We use GNU Radio to do Viterbi decoding and convolutional encoding, using the flowgraph shown below.

The data is read from a file that was produced with the Jupyter notebook. Then both the decoded output and the re-encoded output are written to files. For the input of the Viterbi decoder we are using soft symbols, which preserve the amplitude data and give much better error correction performance than hard symbols (which are just 1’s and 0’s).

In this case, to pair the received symbols correctly we need to throw away the first symbol, so that the symbols that get paired are the second and third together, fourth and fifth, etc. It might have happened that the correct pairing was the first and second together, third and fourth, etc. In that case we wouldn’t throw away the first symbol.

In the Jupyter notebook we can compute the average bit error rate and see that it’s only 1.6%, which is quite good. Presumably all these bit errors would be corrected by the Viterbi decoder. The figure below shows the bit error rate measured in a moving window of 50 bits. We see that occasionally around 5 out of 50 bit are wrong, but we also have some relatively long periods without any bit errors.

Something worth mentioning is that Voyager 1 uses the legacy NASA-DSN convention for the convolutional code instead of the more modern CCSDS convention. The difference between these two conventions is just the order in which the two bits in each encoded pair are sent, as described in Figure 3 of this document .

Finding the ASM

The next step in decoding is to find the Attached Synchronization Marker (ASM), which is a fixed sequence (often 32 bits long) that marks the beginning of each frame. If we know which ASM is used, we can simply correlate the decoded bits with the ASM to find in which places the ASM appears (even if there are some uncorrected bit errors). If we don’t know the ASM, sometimes it is possible to find it by correlating the decoded bits with themselves and finding which parts of the data repeat.

The CCSDS standards recommend the use of the ASM 0x1ACFFC1D for convolutionally encoded data (and for other types of data as well). See Section 9 in the TM Synchronization and Channel Coding Blue Book . This choice of ASM is followed in the present day by many missions. However, it turns out that Voyager 1 uses a different ASM, since it probably predates the standardization of 0x1ACFFC1D .

I have to thank Richard Stephenson , from Canberra DSN , for telling me that the ASM used by the Voyager probes is 0x03915ED3 . It is very difficult to find this data on the internet, since there doesn’t seem to be detailed documentation for how the telemetry transmission of Voyager works. Nevertheless, there is a very interesting report from DESCANSO about Voyager telecommuncations . It also appears as a chapter in this book . However, it focuses more on the RF side of things and does not give all the details about the digital communications aspects.

Here we have some difficulties, because the frame length used by Voyager 1 for transmission at 320 baud is 7680 bits. Taking into account that due to convolutional encoding the net data rate is 160 bps, a frame takes 48 seconds to transmit. Since our recording is only 22.57 seconds long, we don’t even have a complete frame inside the recording. However, it turns out we’re lucky and we have the beginning of a frame, including the ASM.

The figure below shows the results of the correlation of the bits we have decoded with the ASM 0x03915ED3 . If the ASM is present somewhere in the bits, we expect to see a peak with a value close to 32 or -32 at the location corresponding to where the ASM appears in the bit sequence. The reason why the value could be positive or negative is that there is a 180º phase ambiguity in the subcarrier recovery we did, so we may be looking at the original bit sequence or at the inverted bit sequence (where each 1 has been replaced by a 0 and vice-versa). By detecting whether we see the normal ASM or its inversion, we can detect and correct this ambiguity. The reason why the correlation value could be different from 32 (corresponding to 32 bits matched with the ASM) is that in principle there could still be a few uncorrected bit errors after the Viterbi decoder (though in this case probably all the bit errors were successfully corrected).

We see that the ASM appears two times near the beginning of the data. These two appearances are 64 bits apart, which means that we have the 32-bit ASM, then 32 bits with some other data, and then once again the 32-bit ASM. Then the frame starts, and its end is beyond the end of the recording. I don’t know why the ASM appears twice.

A look at the data bits

Now that we know the location of the ASM, we can align ourselves to the start of the frame and study the data bits. The figure below shows the bits laid in rows of 64 bits. The choice of 64 bits is convenient because it lays things in a roughly square image, which sometimes makes patterns easier to see, and because this puts the two ASMs in consecutive rows.

I have aligned things so that the ASMs are at the beginning of a row. The ASMs are highlighted in dark purple (0’s) and yellow (1’s). The normal data is shown in blue (0’s) and green (1’s). The teal at the beginning and end corresponds to artificial padding I’ve added to fill in a whole number of rows.

We see that there are two long strings of zeros in the data. The presence of these strings of zeros causes the two tones that we saw at the sides of the data subcarrier (the figure is shown again below for convenience). The reason is that when a string of all zeros (or all ones) is sent through the convolutional encoder, its output will consist of an alternating pattern 01010101… This causes the two tones, since for this pattern the transmitted data looks like a square wave, which has spectral lines.

There is no further error correction (such as Reed-Solomon) used by the Voyager probes, so at this point we have finished decoding the data. We have a small part of the end of one frame, and a good portion of the next one. It is extremely difficult to understand what these contain without a knowledge of how the data is encoded.

If we had a longer recording, we could extract multiple frames and compare them. Sometimes it’s possible to see patterns that help us make some sense of the data. If I manage to get my hands on a longer recording, I will surely take a look and post about it.

More technical data

Once we know that the ASM for the Voyager probes is 0x03915ED3 , we can search for this in Google and find very interesting technical information. For instance, Table 1 in page 125 of the “ Telemetry Simulation Assembly Implementation in the DSN ” progress report gives details for the telemetry of several deep space probes from 1983. This table confirms the ASM for Voyager 2 and shows that Galileo also used the same ASM. Back in 1983, when Voyager 2 was much closer to Earth, it transmitted at 900 bps with a 360 kHz subcarrier.

We also have this file and this file from some obscure URL at NASA. I am not sure what these are, but they seem to contain all the data required by the DSN to track a spacecraft (run a support, as they usually call it). They date from February 2017 and contain some XML, but also some lists in plain text embedded in the XML. At some point in these files we have several TELEMETRY_INFO tables with an exact definition of the telemetry parameters. The relevant entry for the recording we are using is this one:

Other entries give configurations with a different symbol rate: 80 baud, 93.2 baud, 1.2 kbaud, 2.4 kbaud, 2.8 kbaud, 5.6 kbaud, 9.6 kbaud, 14.4 kbaud, and 40 baud (uncoded). These entries show the frame size as FS_FRM_LEN_PRIMARY , which is different for each baudrate, and the subcarrier frequency ( SUB_FREQ_HZ ) and ASM ( FS_PATTERN ) , which are the same for all of them. They also show the forward error correction in use. INNER_DECD_TYPE: MCD2 refers to the Viterbi decoder (MCD stands for multi-convolutional decoder).

There are many other interesting details in these files, such as a registry of the system performance including received signal levels and system noise temperature. It is certainly fun to have a thorough look at them.

Software and data

The GUPPI recording used in this post can be downloaded here . it can also be found by searching for target name VOYAGER1 in the Breakthrough Listen open data archive (it has the date 2015-12-30 00:00:00). A much smaller file which only contains the LHCP polarization for the ~3 MHz frequency channel in which the Voyager 1 signal is present can be downloaded here .

The GNU Radio flowgraphs and the Jupyter notebook are in this repository . The following GNU Radio flowgraphs are included.

voyager1_extract.grc , which takes as input the small file that contains only a ~3 MHz channel, locks to the residual carrier with a PLL, and outputs the decimated and filtred data sideband to a file.

voyager1_viterbi.grc , which takes as input the demodulated symbols produced with the Jupyter notebook and runs the Viterbi decoder and convolutional encoder.

voyager1_decoder.grc , which takes as an input the small file that contains only a ~3 MHz channel and performs the complete decoding of the signal, including Viterbi decoding and ASM detection. This is provided for completeness, since due to the short duration of the recording it is better to use an open loop symbol recovery as described in the post to prevent loosing any data due to the acquisition time of the loops.

In this full decoder flowgraph the clock recovery is done by the flowgraph section shown below. The Symbol Sync is used to recover the symbol clock and perform pulse shape filtering. A root-raised cosine pulse shape with the maximum likelyhood time error detector is used in this case, although the choice is not very important. A Costas Loop is used after clock recovery to remove the residual subcarrier.

Viterbi decoding done with the FEC Extended Decoder, using the CC Decoder Definition. The correlation with the ASM is implemented with a Decimating FIR filter and displayed in a QT GUI Time Sink. In order to account for the two possible pairings of received symbols, two copies of the Viterbi decoder are run in parallel. One uses the stream of received symbols, the other uses the same stream but delayed one sample.

The figure below shows the GUI of the GNU Radio decoder flowgraph running. In the bottom we see the constellation plot. In the top we see the detections of the ASM. Te recording is played endlessly in a loop, so we see detections in both Viterbi decoders, due to bit slip when the recording goes again to the beginning.

29 comments

Wow! This is an absolutely fantastic analysis of the GUPPI data from Green Bank Observatory of the Voyager signal. Bravo!!! I hope you can analyze more Breakthrough Listen data for buried carrier signals coming from farther away than Voyager . . .

There is nothing human made that is farther away than Voyager. See the documentary “The Farthest”.

Wonderful! What a thrill to visualize Voyager data on my own computer, even if all the hard work of signal reception & decoding was done by others.

Thank you for putting this together!

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Thanks Daniel…. wonderful work as usual ..

Thanks, Daniel. It is a real pleasure to read such a wonderful and insightful piece of work.

Amazing work, thanks for sharing! It’s so nice to see the Voyagers alive and working fine after all these years. What a great piece of engeneering.

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Great work Daniel. A real pleasure to read. Thanks for sharing.

The Magellan Probe used the same syncword as that of Voyager.

CCSD3ZF0000100000001NJPL3IF0PDSX00000001

PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM SPACECRAFT_NAME = MAGELLAN TARGET_NAME = VENUS OBJECT = TEXT PUBLICATION_DATE = 1995-01-01 NOTE = “MAGELLAN SCVDR ARCHIVE CD-WO” END_OBJECT = TEXT END

#ifndef SAR_H /* From Interface Requirements p.47 */ #define JPL_SYNC 0x03915ED3 typedef struct { uchar jpl_sync[4]; uchar threshold[24]; uchar fill1[2]; uchar radiometer[2]; /* includes 4 filler bits */ uchar fill2; uchar time[7]; /* includes 4 filler bits (rclk_t) */ uchar fill3[2]; uchar status[10]; /* sar_status_fmt */ uchar checkout[2]; } sab_hdr_t; #endif /* SAR_H */

Thanks! That is quite interesting, since it even shows the contents of the telemetry. Do you know by any chance if the structure of the Voyager telemetry is publicly available? I couldn’t find anything.

The structure is pre-defined but may be one of several different formats depending on the nature of the data. At least it used to be.

https://github.com/NASA-AMMOS/VICAR/blob/4504c1f558855d9c6eaef89f4460217aa4909f8e/vos/p2/prog/visis2/visis2.c#L393

https://webcache.googleusercontent.com/search?q=cache:C42e0qDgoMgJ:ftp://pds-geosciences.wustl.edu/mgn/mgn-v-rdrs-5-scvdr-v1/mg_2134/software/types.h+&cd=1&hl=en&ct=clnk&gl=ru

I worked at JPL in the 80’s, and the sequence 0x03915ED3 was used all over the place. We called it a PN (Pseudo Noise) code. It’s basically the output of a 5 bit LFSR circuit that exhibits a white spectrum. In the hardware I designed, I had to detect the code both forwards and reverse, because we used it on a Shuttle Radar project where the data was sometimes played backwards from an onboard tape recorder when downloading via TDRSS at 45 Mbits/sec.

Thanks for that interesting bit of history. I saw in old papers that that sequence was also used in other satellites besides the Voyagers. What’s interesting is that at some point this sequence fell in disuse in favour of the CCSDS 0x1ACFFC1D, which I think has also good autocorrelation properties, but I don’t think is any better or worse than 0x03915ED3.

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More great work!

I’m curious, do you know of any particular reason that CCSDS chose 0x1ACFFC1D as their frame sync marker? Perhaps an exhaustive search for one with good autocorrelation properties?

Hi Phil, I haven’t seen an explanation of how that particular bit pattern was obtained. The Green Book doesn’t say. If I were to design one myself, I’m not even sure of exactly which “quality” metric I would use for an exhaustive search. In a certain sense, we need to account for how the message bits adjacent to the syncword (which we can probably model as random) affect the cross-correlation.

A simple idea that comes to mind to obtain something that is more or less okay (but probably not the best) is to start with a 5-bit LFSR, and obtain the corresponding 31-bit M-sequence. I think this will have 16 1’s and 15 0’s, so if we want to obtain a syncword which is balanced (same number of 1’s and 0’s), then we should extend it with a 0. The CCSDS syncword is quite far from this because it has 19 1’s. It also has a run of 10 consecutive 1’s, while the length of the longest run of 1’s of a 5-bit LFSR would be 5. Maybe these remarks can give some ideas about how the CCSDS syncword was constructed, but at the moment I don’t see exactly how.

I believe papers were written on this subject by Laif Swanson, the mathematical basis for how those bit strings were decided on.

Thanks! Do you have some references about this? I did some Googling and took a look at her papers “A Comparison of Frame Synchronization Methods”, “Synchronization at low signal-to-noise ratio”, and “Node Synchronization for the Viterbi Decoder”. I didn’t find a discussion of why these syncwords were chosen. The closest to this is perhaps Section VI in “A Comparison of Frame Synchronization Methods”, but I found it somewhat brief and vague.

You ask ” I don’t know why the ASM appears twice.” During certain playback modes, entire frames are chopped up and sent down inside areas of other frames. Sometimes the playback data contains the start of a frame. This is why simply finding the sync marker is not enough. It must be the correct distance apart from the next marker. Other parameters and checks are applied before a frame can be declared valid and useful. If they are not applied, the data can be used but it may be suspect.

Hi Daniel, Thanks from this Voyagerphile in the UK. Slowly working through examples, learning so much. As the proverb goes:- I read, I know I do, I understand.

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22.5 light hours —

Recoding voyager 1—nasa’s interstellar explorer is finally making sense again, "we're pretty much seeing everything we had hoped for, and that's always good news.”.

Stephen Clark - Apr 23, 2024 5:56 pm UTC

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-and-a-half 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 data stream 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 data stream 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 antennas 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 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."

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 a single chip responsible for storing a portion of the FDS memory 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.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

More on this story

Cosmic cleaners: the scientists scouring English cathedral roofs for space dust

Russia acknowledges continuing air leak from its segment of space station

Uncontrolled European satellite falls to Earth after 30 years in orbit

Cosmonaut Oleg Kononenko sets world record for most time spent in space

‘Old smokers’: astronomers discover giant ancient stars in Milky Way

Nasa postpones plans to send humans to moon

What happened to the Peregrine lander and what does it mean for moon missions?

Peregrine 1 has ‘no chance’ of landing on moon due to fuel leak

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NASA makes sense of Voyager 1's garbled signals from the edge of the solar system

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• Nell Greenfieldboyce, NPR

Voyager 1 was originally launched in the 1970s, and the space probe is now sailing outside our solar system. A computer glitch scrambled its communications with Earth, leaving NASA in the dark.

Now, scientists have restored Voyager 1 and are making sense of its signals from interstellar space.

NPR science correspondent Nell Greenfieldboyce reports.

This segment aired on April 24, 2024.

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Anjana Ahuja

Roula Khalaf, Editor of the FT, selects her favourite stories in this weekly newsletter.

The writer is a science commentator

A ghost has come back to life. Voyager 1, a spacecraft dispatched in the 1970s that had been sending signals back to Earth continuously until it malfunctioned in November, has been revived. Nasa engineers revealed last week that, thanks to some clever workarounds, they had remotely fixed the corrupted memory in one of its three onboard computers.

Gone is the melancholic string of ones and zeroes that signalled little beyond a pulse. Voyager 1, now outside the solar system and the most distant man-made object at 24bn km away, has begun sending meaningful signals once again.

The news feels both uplifting and bittersweet. Uplifting, because it embodies a golden age of space exploration that kicked off in the 1950s, put men on the moon, and gave us the first true glimpse of our planetary neighbourhood. Bittersweet, because this craft feels like a relic from a different era — one in which horizons were literally expanding, ambition and optimism were abundant, and technology seemed built to last.

The twin Voyager mission was launched in my childhood and, ever since, it has been hard not to romanticise it as a fellow traveller: sent off alone into the wilderness; writing home; reaching milestones; and now weakening as it glides into the void between stars. For those of us of a certain age, its timeline mirrors our own. Voyager 1 arrived at Saturn as I started secondary school, and its sister craft, Voyager 2, reached Uranus as I left. The latter approached Neptune while I danced at university balls. For me, it is more than a nostalgic cultural touchstone: its data featured in my doctoral thesis.

This week’s resuscitation is the epilogue to a sequence of historic missions to the outer planets, beginning with Pioneer in the early 1970s. Pioneer 10 became the first spacecraft to travel beyond Mars and through the asteroid belt; it beamed back the first close-up pictures of Jupiter and sent its last signal to Earth in 2003. Pioneer 11 journeyed successfully to Saturn, where it discovered a new ring and two moons — but went quiet in 1995.

This laid the groundwork for Voyager 1 and Voyager 2, launched a few days apart in 1977. That year, Jimmy Carter entered the White House, Pelé hung up his football boots and I queued with my brother at the cinema to watch the original Star Wars . The launch took advantage of a rare planetary alignment — happening just one every 175 years — that provided gravitational kicks along the journey, saving on propellant and time.

The twin spacecraft exceeded expectations at every orbital turn. Thanks to some nifty remote programming after launch, the mission to Jupiter and Saturn expanded into a four-planet odyssey, with Voyager 2 taking in fly-bys of the ice giants Uranus and Neptune. This “grand tour” rewrote planetary textbooks, furnishing new images and measurements of the outer planets, many moons and their associated magnetic fields.

Voyager 1 left the solar system in 2012. Its companion, also still functioning, exited in 2018. Today, signals from Earth to Voyager 1 — and vice versa — take more than 22 hours to arrive. Its power should last a few more years yet, during which scientists hope it will reveal characteristics of interstellar space.

As the sun runs out of fuel and dies in a few billion years, so will life on Earth (if it hasn’t before then). Assuming the pair survive the interstellar dust, the analogue technology on board will become a memento of a vanished civilisation. Each craft carries a Golden Record, with contents overseen by American astronomer Carl Sagan. Each 12-inch gold-plated, engraved copper disk contains sounds and images of life on Earth, including spoken greetings in 55 languages.

The Hebrew message is “Peace”. If Voyager 1 had its own voice, that would surely be its message back to us. 

Letter in response to this article :

Advanced extra­ter­restri­als find Voy­ager 1. Just ima­gine  /  From Ros­ario A Iaconis, Adjunct Pro­fessor, Social Sci­ences Depart­ment, Suf­folk County Com­munity Col­lege, Mineola, NY, US

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Music from earth.

The following music was included on the Voyager record.

• Bach, Brandenburg Concerto No. 2 in F. First Movement, Munich Bach Orchestra, Karl Richter, conductor. 4:40
• Java, court gamelan, "Kinds of Flowers," recorded by Robert Brown. 4:43
• Senegal, percussion, recorded by Charles Duvelle. 2:08
• Zaire, Pygmy girls' initiation song, recorded by Colin Turnbull. 0:56
• Australia, Aborigine songs, "Morning Star" and "Devil Bird," recorded by Sandra LeBrun Holmes. 1:26
• Mexico, "El Cascabel," performed by Lorenzo Barcelata and the Mariachi México. 3:14
• "Johnny B. Goode," written and performed by Chuck Berry. 2:38
• New Guinea, men's house song, recorded by Robert MacLennan. 1:20
• Japan, shakuhachi, "Tsuru No Sugomori" ("Crane's Nest,") performed by Goro Yamaguchi. 4:51
• Bach, "Gavotte en rondeaux" from the Partita No. 3 in E major for Violin, performed by Arthur Grumiaux. 2:55
• Mozart, The Magic Flute, Queen of the Night aria, no. 14. Edda Moser, soprano. Bavarian State Opera, Munich, Wolfgang Sawallisch, conductor. 2:55
• Georgian S.S.R., chorus, "Tchakrulo," collected by Radio Moscow. 2:18
• Peru, panpipes and drum, collected by Casa de la Cultura, Lima. 0:52
• "Melancholy Blues," performed by Louis Armstrong and his Hot Seven. 3:05
• Azerbaijan S.S.R., bagpipes, recorded by Radio Moscow. 2:30
• Stravinsky, Rite of Spring, Sacrificial Dance, Columbia Symphony Orchestra, Igor Stravinsky, conductor. 4:35
• Bach, The Well-Tempered Clavier, Book 2, Prelude and Fugue in C, No.1. Glenn Gould, piano. 4:48
• Beethoven, Fifth Symphony, First Movement, the Philharmonia Orchestra, Otto Klemperer, conductor. 7:20
• Bulgaria, "Izlel je Delyo Hagdutin," sung by Valya Balkanska. 4:59
• Navajo Indians, Night Chant, recorded by Willard Rhodes. 0:57
• Holborne, Paueans, Galliards, Almains and Other Short Aeirs, "The Fairie Round," performed by David Munrow and the Early Music Consort of London. 1:17
• Solomon Islands, panpipes, collected by the Solomon Islands Broadcasting Service. 1:12
• Peru, wedding song, recorded by John Cohen. 0:38
• China, ch'in, "Flowing Streams," performed by Kuan P'ing-hu. 7:37
• India, raga, "Jaat Kahan Ho," sung by Surshri Kesar Bai Kerkar. 3:30
• "Dark Was the Night," written and performed by Blind Willie Johnson. 3:15
• Beethoven, String Quartet No. 13 in B flat, Opus 130, Cavatina, performed by Budapest String Quartet. 6:37

NASA hears from Voyager 1, the most distant spacecraft from Earth, after months of quiet

CAPE CANAVERAL, Fla. (AP) — NASA has finally heard back from Voyager 1 again in a way that makes sense.

The most distant spacecraft from Earth stopped sending back understandable data last November. Flight controllers traced the blank communication to a bad computer chip and rearranged the spacecraft’s coding to work around the trouble.

NASA’s Jet Propulsion Laboratory in Southern California declared success after receiving good engineering updates late last week. The team is still working to restore transmission of the science data.

It takes 22 1/2 hours to send a signal to Voyager 1, more than 15 billion miles (24 billion kilometers) away in interstellar space. The signal travel time is double that for a round trip.

Contact was never lost, rather it was like making a phone call where you can’t hear the person on the other end, a JPL spokeswoman said Tuesday.

Launched in 1977 to study Jupiter and Saturn, Voyager 1 has been exploring interstellar space — the space between star systems — since 2012. Its twin, Voyager 2, is 12.6 billion miles (20 billion kilometers) away and still working fine.

The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Science and Educational Media Group. The AP is solely responsible for all content.

Copyright 2024 The Associated Press. All rights reserved.

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