Short Wave - The Recent Glitch Threatening Voyager 1

Episode Date: March 6, 2024

The Voyager 1 space probe is the farthest human-made object in space. It launched in 1977 with a golden record on board that carried assorted sounds of our home planet: greetings in many different languages, dogs barking, and the sound of two people kissing, to name but a few examples. The idea with this record was that someday, Voyager 1 might be our emissary to alien life – an audible time capsule of Earth's beings. Since its launch, it also managed to complete missions to Jupiter and Saturn. In 2012, it crossed into interstellar space. But a few months ago, the probe encountered a problem. "It's an elderly spacecraft," says NPR science correspondent Nell Greenfieldboyce, "and it had some kind of electronic stroke." Greenfieldboyce talks to Short Wave Host Regina G. Barber about the precarious status of Voyager 1 – the glitch threatening its mission, and the increasingly risky measures NASA is taking to try and restore it. What interstellar adventure should we cover next? Email the show at [e-mail] pcm.adswizz.com for information about our collection and use of personal data for sponsorship and to manage your podcast sponsorship preferences.NPR Privacy Policy

You're listening to Shortwave from NPR. Hey, shortwavers, Regina Barber here. And today we're going to check in on an intrepid piece of space hardware known as Voyager 1. The space probe launched in 1977, and even back then, scientists knew it would venture far, far out beyond our solar system. Hello from the children of planet Earth. That's why Carl Sagan and his buddies got NASA to put a golden record on board, with greetings in many language. And sounds of Earth and sounds of Earth like a dog barking.

The idea was that maybe someday aliens would encounter the spacecraft and learn about the life forms that created it. Voyager 1 is now about 15 billion miles away. Believe it or not, it still has power and talks to controllers back here on Earth. But a few months ago, it developed a problem, a serious problem. serious problem. And whenever we need to check in with aging space hardware, we turn to NPR's Nell Greenfield Boys. Hey, Nell. Hey. So tell us what's going on. My understanding is that Voyager 1 is not making any sense right now. Its messages are just like incoherent. That is in fact, sadly,

the case. So this is an elderly spacecraft. And back in like mid-November, it sort of had some kind of electronic stroke. Instead of sending back information in the binary code it uses, it's sending just alternating ones and zeros. Okay. I like the next astronomer, love Voyager 1, but is it actually still contributing to science even now? Before this glitch, it absolutely still was.

I talked to somebody who wasn't even born when Voyager 1 launched, but she depends on its data to study this mysterious region between stars. And NASA has a whole team working hard. to see if it can get the spacecraft back in action. Today on the show, we're going to discuss what exactly Voyager 1 is still doing out there that's useful and what NASA is trying to do to save it. You're listening to Shortwave, the science podcast from NPR. Okay, so when Voyager launched back in the 1970s, what was its original mission?

So the original mission was going to last just four years. Okay. The plan was to go to Saturn and Jupiter, and there were actually two spacecraft. It was Voyager 1 and Voyager 1 and Voyager. 2. As they kept going, NASA kept the mission going. They added flybys of Uranus and Neptune. Voyager 2 is the only spacecraft to ever visit Neptune. That was all the way back in 1989. And, you know, they've just kept going. Right. And they've actually like left the solar system, right? Well, I mean, that depends on how you define the solar system. Okay. So they are beyond Pluto.

They are beyond the heliosphere. And that is the sphere of space that's, you know, dominated by activity from our sun, the nearest star. So Voyager 1 left that in 2012, and Voyager 2 left it in 2018. And those were huge, like, sort of landmark historic events. Right. But Ed Stone, who led the Voyager mission for 50 years, has talked about the Orte Cloud. And so the Ort Cloud is this way out there cloud of small rocky bodies that surrounds the sun. And it is so far out, it will take hundreds of years for the Voyagers to even get there and then thousands of years to go through it.

Wow. So do you include the Ork Cloud in thinking about the solar system? I don't know. Right. So the Voyagers aren't there yet. They're kind of traveling through empty space right now, right? So if you were like riding on Voyager 1, you would see a lot of blackness. Well, yeah.

But Stella Ocker told me it's actually not just emptiness. It's a kind of cosmic stew. So she's a researcher at Caltech and the Carnegie Observatories. And she says there's a lot of emptiness, but there's also little particles, cosmic rays, there's dust. And only Voyager is immersed in that and actually taking measurements. Imagine you're standing on the beach and you're looking out of the ocean. There's a big difference, right, between observing the ocean from land versus actually being out on the waters, feeling the water, taste. the salt spray in your mouth. And that's really the difference between observing interstellar space

from Earth using remote observations versus using Voyager. And for the particular kind of stuff she studies, like the parts of that sort of cosmic ocean that she's interested in, she really needs Voyager 1 specifically. Because the twins were twins, but over the years they've aged in different ways. And Voyager 2 can still do plenty of science and take plenty of measurements and it's communicating with Earth. But to take the exact measurements she needs, it can only be done with Voyager 1. And that's why its current problem is such a bummer for her. So, okay, we talked about this earlier, but like, tell me exactly what's happening to Voyager 1 right now. Right. So it can still communicate with Earth. They can still, you know, send a command and it receives it and it's

sending stuff back. But instead of, like, data, in the binary code that they're used to, it's just sending back nonsense. It's just alternating ones and zeros rather than real information. And so I talked with Suzanne Dodge. She's the Voyager project manager now. We know the spacecraft is actually getting data. It's just that it can't, when it tries to talk to us, it just can't coherently format that data.

And so we don't understand it. And it makes it difficult to diagnose what the problem might be, because we don't understand what the spacecraft is telling us. They've tried doing the usual things they do like anyone would do, you know, like with your computer, you try to restart it, you know, you just try to reset things. But all that stuff didn't work. And they've been trying to do this since November. Yeah.

And it's not easy, you know, because remember, the Voyager probes have been around a long time. They've actually outlived some of the people who designed and built them. Yeah. And that means the dozen or so people who are on Dodd's team now have had to sort of pull. over yellow documents and mimeographs. Like, some younger people may not even know what mimeographs are. There are these papers. You sort of print with blue or purple ink using this machine that pushes the ink through a stencil.

It's like really old school. Wow. I remember it from my childhood. Anyway, that's the kind of stuff the team is looking at now. They're doing a lot of work to try and get into the heads of the original developers and figure out why they designed something the way they did and what we could possibly try, that might give us some answers to what's going wrong with the spacecraft. She told me they've narrowed the problem down to the flight data computer that sort of packages up information and then sends it back home to Earth.

And she told me this technology is really primitive compared to like a car key fob. Wild. The button you press to open the door of your car that has more compute power than the Voyager spacecrafts do. You know, it's remarkable that they keep flying and that they've, and that they've, and that they've flown for 46 plus years. So they're not giving up. They have a list of things to try. But as time goes on, they're going to have to start trying things that are kind of more risky,

you know, like a little more bold than the usual go-toes. How long are they going to keep trying? I mean, this could take weeks, months. They'll send commands to the spacecraft. And it's, you know, a painstaking process because Voyager 1 is so distant, it takes almost a whole day for the signal to just get to the spacecraft. and then a whole day for its response to return, just traveling through space, literally. This must be a really difficult time for those scientists who have been, like, working with Voyager,

and especially the ones that, since the get-go, have been working with Voyager. It is, yeah. So for them, Voyager 1 is like this old dear friend who suddenly has been hit with a terrible illness. Yeah. I called up Tom Kramigas. He's with the Johns Hopkins University's applied physics lab. Well, frankly, I'm very worried. He's been involved with space missions to every planet, and he just told me, frankly, that Voyager is number one. It's number one in his heart.

Oh, that's like, that's so sweet. And, like, it's really actually odd to hear because scientists, they don't pick a favorite. It's like picking a favorite child, right? Yeah, but Voyager is a legend. And, you know, he told me it's been part of his whole life. I mean, he designed and built an instrument that's on both probes. I was believed around the world because my instrument. He thought for sure that that moving part would stop moving a while back when it was plunged into frigid cold because mission managers turned off some heaters and they turned them off as a measure to conserve power. Wow.

They want to extend Voyager's lifespan. And, you know, he told me he thought that was going to be it, but it just kept working. My motto for 50 years for bust. But we're sort of approaching that. I mean, even if this current crisis gets solved, in a couple of years, the power supply is just going to get lower and lower. It will force managers to start turning off science instruments one by one. Okay, so let's assume this problem gets fixed.

How long do they think the Voyagers can keep doing science and communicating with Earth? I've seen estimates that the very last remaining instrument could keep going until 2030. Wow. And after that, Kramigas says both of these legendary space probes will basically become space junk. That's the term he used with me. It pains me to say that. Now, I did talk to somebody who said, the mission will go on,

the Voyager mission will continue, because the probes are carrying those golden records that have all the sounds of Earth. Yeah, I mean, they're going to be our emissaries to aliens, right? That's right, just like in that Star Trek movie that came out after the Voyagers launched. Star Trek, the motion picture? I don't know.

Listen, Gina. I mean, space is very big. It is. Kramigis says, personally, he is pessimistic that anyone out there will ever hear those golden records. I mean, come on, it's going to be another 40,000 years before Voyager approaches another star. Okay. But do you think that there's going to be, like, another mission like Voyager?

I did talk to a team that's planning an interstellar probe. So NASA has been thinking about what after Voyager, and people have plans in the works for an interstellar mission that is planned to last at least 50 years, like deliberately. Wow. Not just sort of accidentally working that long. That one would go out faster than Voyager. The idea is that it could go out twice as far. But it remains to be seen if NASA is going to fund it and support it and if it's really going to launch. Well, I'm going to be optimistic and say, yes, it's going to happen.

I'm very excited. Absolutely. Even if aliens never hear the golden record, people on Earth can listen to it. And I think it brings people a lot of joy. Oh, thank you so much, Nell, for bringing that story to me. Thank you for having me. Before we head out, a quick shout out to our Shortwave Plus listeners. We appreciate you and we thank you for being a subscriber.

Shortwave Plus helps support our show. And if you're a regular listener, we'd love for you to join so you can enjoy the show without sponsor interruptions. Find out more at plus.mpr.org slash Shorewave. This episode was produced by Margaret Serino and edited by Jeff Rumfield. Our showrunner is Rebecca Ramirez. Gilly Moon was the audio engineer. I'm Regina Barber.

I'm Nell Greenfield. voice. Thanks for listening to Shortwave from NPR.