Short Wave - Odd Radio Circles Are glowing Around Some Galaxies. Now We Know Why

Episode Date: January 12, 2024

Since they were discovered in 2019, strange, glowing circles of light in space have mystified researchers. Now called odd radio circles, or ORCs, these rings of light sit in the radio portion of the electromagnetic spectrum. They pulse out of the centers of some galaxies – and until now, no one knew why.In this episode, host Regina G. Barber talks to Alison Coil, a professor of astronomy and astrophysics at University of California San Diego, about her latest research. They break down what ORCs are, where they come from and what they might reveal about how galaxies evolve over billions of years.Wondering about other happenings across the universe? Email us at [e-mail] – we'd love to hear about it! See 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, short wavers, Regina Barber here, and this time I've got Jeff Brumfield. Hey, Jeff. Hi there. And Jeff, for our regular roundup of science news, Mary Louise Kelly is joining us. Hello, hello. Glad to be with you, too. Mary Louise, as always, we're going to share three science stories in the news that have caught our attention recently.

We've got a moon mission gone awry. Tracking fishing across the world's oceans with AI. I love your rhyming. and mysterious radio circles that had astronomers baffled. Just dropped the ball at the end there, didn't you? All of that on this episode of Shortwave, the science podcast from NPR. All right, Mary Louise, you're the guest. Which topic do you want to start with first?

All right, well, I've got to go out to space and the moon. What's up with this moon mission? So this was a little robotic spacecraft called the Peregrine lander. It was built by a company called Astrobotic. It would have been the first American probe to land on the moon since the Apollo era of the late 60s and early 70s. It launched on Monday. Everything looked good, but then it experienced a problem with its propulsion system.

And by Tuesday, the company had figured out there was a leak and that the spacecraft wasn't going to make it to the moon. They have been able to do some experiments that were loaded onto the Peregrine before it lost power, however. Ah, okay. So this was a private company, private mission. What does it mean for NASA? You know, this is an interesting time for NASA. It's trying to send humans back to the surface of the moon. And in the 1960s, it did it, but it did it on its own using an enormous expenditure of taxpayer dollars. Yeah, and now fast forward more than a half a century, and NASA's budget is much tighter. It's trying to use the private sector to do things cheaply. It's given this company Astrobotic and other companies money in hopes that they could become a delivery service to the moon. Basically, you could take NASA's equipment and supplies up there for less. And it's true, the private sector can be cheaper, but we're also seeing the downside, which is there's just more risk involved.

Things can go wrong. And big picture, where does this leave NASA's mission, which you just told me was trying to get humans back to the moon? Yeah, well, there's good news that NASA has invested in other companies as well. A second one called intuitive machines will attempt to launch its own moon mission next month. And astrobotic will get another try. They're supposed to deliver a rover to the lunar surface later this year, though they'll likely want to learn. from their mistake in this mission first, so it might be delayed. Ness also announced this week that it's pushing back its plans to send humans to the moon

because of ongoing issues with the capsule that's supposed to carry them. So it's now aiming to have astronauts orbit around the moon in 2025 and maybe land there in 26. So that's all pushing everything back by about a year from the previous schedule. But this year is still going to be a pretty exciting one for the moon. We've got several commercial missions. We've got another Chinese lander scheduled to fly there and collect a sample from the far side of the moon. That's something that's never been done before. And more flights of Elon Musk's giant starship, which isn't completely related to the moon,

but starship may end up doubling as a lunar lander for astronauts in the future. So it's important for NASA's plans. All right. I'm going to move us back to planet Earth, where I gather you have found us some really good news, a use of AI, artificial intelligence that is unambiguously good. What is it, Regina? Yeah, that's right. We're always worrying about AI, like taking our jobs, taking over the world or something.

But we have a case where AI is being used to do something really important, and that's to track fishing boats. So commercial fishing is a really big source of food for much of the world, but there's sort of a problem with it, which is the oceans aren't owned by anyone. The boats move around, the fish move around. And so it's really hard to keep track of who's fishing where and what's going on. Yeah. And among the things going on, of course, is too much fishing, overfishing, illegal fishing. This is going to be helpful with that. Yeah. I mean, there's nonprofits like Global Fishing Watch, and they're trying to bring more transparency to the fishing industry. And they want to help quantify who's fishing where so the oceans can be better managed.

Earlier this month, Global Fishing Watch announced that they had a breakthrough. They used an AI algorithm to look at an enormous number of satellite images. and it could identify millions of vessels between 2017 and 2021. And that led to some surprising discoveries. Like what? Well, first off, they found out that three quarters of industrial fishing vessels had gone undetected in previous surveys. Fernando Paolo is with Global Fishing Watch. He said that came as a real shock. We knew we were missing a big chunk of activity.

We didn't know how much. In fact, we had to completely remake our fishing maps because of these findings. They could see some big fishing hotspots they basically completely missed before, for example, in the Bay of Bengal and off the coast of North Korea. So fascinating. So they can see all these fishing vessels. They didn't know where out there. What does that mean? What are they going to do with those?

Well, I mean, it's important to remember that not all these vessels are fishing illegally. There's different rules about, you know, who's supposed to carry tracking equipment and transponders, things that have been used to conduct surveys of vessels in the past. But the hope is this tool can really show governments all over the world where the action is and leave them better equipped to try and manage the world's fisheries. Okay. Our last topic, I'm so excited for this one, since we're NPR and we're radio, mysterious radio rings in space. Regina, go. Right. I mean, I'm super excited about this, too, because it's so rare that astronomers detect something in space they've never seen before.

Like, for example, astronomers have recently been excited. about pictures of the early universe showing baby galaxies we've never seen before, but we knew they were galaxies, right? But in 2019, scientists detected these glowing rings in the radio end of the light spectrum in several parts of the sky. And they truly had no idea what they were. They named them orcs. Orcs.

This isn't, yeah, not Lord of the Ring orcs. This is something called an odd radio circle. These rings were huge. Like one of them was four times the size of the Milky Way. Four times the size of the Milky Way. So absolutely ginormous. But they had no idea what they were? That's a little terrifying.

Yeah, they had no idea. So I talked to Alison Coyle about this. She's an astronomer and a professor at the University of California, San Diego. And she published a paper in nature about one radio ring in particular. So on top of the weird ring being there, there was a galaxy in the center that had something very strange going on. So there was this, like, absurd amount of oxygen two gas. Lots of it and really extended. And, I mean, I should say an absurd amount of oxygen for an astronomer is not the same as an absurd amount of oxygen for the rest of us.

I mean, it's still, you know, vastly less dense than our atmosphere. But it's way more than you'd expect to see around a galaxy. Okay. So, y'all are stacking up clues here. We've got mystery oxygen. We've got mystery radio rings. Did we figure it out? Like, did one help explain the other?

Yeah. So the oxygen turned out to be a clue that helped Allison and our team find out where these radio rings came from. She said the oxygen showed evidence of being shocked. So that's gas that's been created by a big, very fast-moving explosion. So then I had to go to theorists and be like, why would there be all of this shocked gas? And after running some simulations, they concluded it had to do with the stars in the galaxy. Basically, they think a big bunch of those stars were born all at once in what they call a starburst. And then they lived their little star lives and grew old together.

And eventually the biggest ones all exploded all at the same time. And those explosions are what created the shockwave. And that shockwave created these mysterious radio rings. At least that's what the simulations say. Mystery solved pretty quick after 2019. And now that we know what they are, we can start studying more of them. I love it. I love a good mystery.

Mary Louise, thank you so much for hanging out with us. My pleasure. Anytime. You can also catch Mary Louise on Consider This, NPR's Afternoon News podcast. Before we head out, a quick shout out to our Shortwave Plus listeners, we appreciate you, and thank you for being a subscriber. Shortwave Plus helps us 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.npr.org forward slash shortwave. This episode was produced by Margaret Serrino and Gus Contreras. It was edited by Christopher Entellata and Rebecca Ramirez. Britt Hansen checked the facts and audio engineers were Josh Newell and Valentina Rodriguez Sanchez. Beth Donovan is our senior director and Colin Campbell, is our Senior Vice President of Programming.

I'm Regina Barber. Thanks for listening to Shortwave from NPR.