Short Wave - Osiris-REx and the quest to understand the solar system's origin

Episode Date: September 27, 2023

In 2016, NASA launched a spacecraft to do something rarely attempted before: Collect space rocks from a potentially dangerous asteroid. The mission, named OSIRIS-REx, was successful. Tuesday, scientists opened a sealed canister containing the samples from the asteroid Bennu. Science correspondent Nell Greenfieledboyce talks to host Regina G. Barber about the mission's close calls and what NASA might learn from these space rocks that are older than our planet. Listen to Short Wave on Spotify, Apple Podcasts and Google Podcasts.Have a space mystery? Send us your questions to [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

Hey, Shorewavers, Regina Barber here. So before we begin, heads up that next week is NPR's Climate Week. We'll spend seven days focused on innovators working to build a better world for the next generation and the one after that. On Monday's episode of Sort Wave, we'll hear how a robot is cleaning up toxic seaweed. You can also check out more stories of human ambition fighting very human problems at npr.org slash climate week for a spotlight on solutions. You're listening to Shortwave from NPR. Earlier this week, a scientist named Dante Loretta was in a helicopter. In a desert outside of Salt Lake City, there's a big military range there.

Recovery operations, helicopters one and two have arrived at the holding location. Nearly two decades of work have come down to this, waiting in a helicopter. SRC is experiencing maximum duty and maximum deceleration. Loretta. The guy in the helicopter is a University of Arizona researcher who heads up NASA's first mission to collect rocks from an asteroid. On Sunday morning, a UFO-shaped capsule full of these rocks just entered the atmosphere going 36 times the speed of sound. And Loretta was anxiously waiting for word that the capsule had deployed its parachutes. You know, the parachutes that would slow it down and keep it from crash landing and smashing into smithereens, he waited and waited.

And so I was mentally preparing myself for the worst-case scenario. I always said this is like you're the championship game, you've just thrown the touchdown, winning pass, and you fumble it out of bounds. That's what my nightmare was. It's like I can't lose this at the last minute. He imagined himself getting out of the helicopter and having to somehow keep himself together in front of an international audience after the capsule crash landed. But then... ...steed-mile-so. They have confirmed parachute to dolemen. That's when I just emotionally just let it go.

You know, tears were streaming down my eyes. I was like, okay, that's the only thing I needed to hear. From this point on, we know what to do. We're safe. We're home. We did it. Touchdown. I repeat, DEO.

FRC has touchdown. The capsule looked like a charcoal briquette sitting there on the ground. It was all charred from its fiery re-entry. And NPR's science correspondent, Nell Greenfield, Boyce, was watching it all go down. Hey, Nell. Hey. As I understand it, you've been covering this NASA mission for some time, right? Oh, yeah, years, years.

And it's been a fun one. It's been kind of a wild ride with lots of twists and turns. That's why I'm super excited to talk about asteroid rocks with you. Today on the show, we're going out to a potentially dangerous asteroid and back, and to a special lab at NASA's Johnson Space Center, where scientists are finally getting to learn the secrets of these strange black rocks. I'm Regina Barber, and you're listening to Shortwave. from NPR. All right, now, you know I'm a sucker for anything space, but let's just set the scene here.

Why does NASA care so much about asteroids and getting samples from an asteroid? So asteroids are thought to be kind of leftovers from when the planets formed in the early days of the solar system. They've been undisturbed for billions of years. They're older than the Earth, and they're basically relics, kind of like little time capsules. They fall to Earth as meteorites all the time, but those meteorites that you could just pick up off the ground, they're contaminated by all of our Earth stuff here. So what scientists would really like is to get some pristine samples, you know, ones that haven't been cluttered up with Earth stuff. And then you could study them in the lab and get an idea about what kind of chemistry was around way back when when everything was getting its start. And what ingredients, you know, asteroids might have brought to Earth and helped get. life going here. So there are a lot of asteroids out there. Which one actually gave us these rocks?

Well, it didn't exactly give them to us. We took them. We stole them. The asteroid is called Benu. It's about the size of the Empire State Building. So, you know, not that big, like a small mountain maybe. It's considered to be a potentially dangerous asteroid. That means there's a small chance that, like, a long time from now, over a century from now, its path might make it collide with Earth. It's a little scary. Yeah. But, you know, it's a long way off and scientists are aware of it and they're tracking it. You know, I just, it's not a big deal. I just mention it since the threat of being obliterated by an incoming space rock is just another reason to learn about asteroids. True. And, you know, that's why NASA developed this mission. So the mission is called Osiris Rex. Everybody calls it Osiris Rex.

It's an acronym. NASA loves its acronym. Do you want to know this one? Yeah, I do. It's origins, spectral interpretation, resource identification, security regolith explorer. So, you know, super catchy Osiris Rex. It launched in 2016, so like seven years ago. It took it a couple years to get to Benu. And, you know, it orbited for a while, just checking it out. And this asteroid didn't look like the researchers thought it would. What do you mean?

What did they think? Well, they expected the surface to be fairly smooth, like almost sandy. And, you know, they were going to touch down on this like smooth, flat surface. But instead, it was just covered with rocks and craters and jaggedy things. And so they had to map out this whole route to get the spacecraft down into a crater, you know, pass some rocks with nicknames like Mount Doom. And the idea was that the spacecraft, which is about the size of like a big passenger van, had to fit into a spot that was just like the size of a few parking spaces. Wow. So, you know, I think when I was on shortwave three years ago talking about this, I said that I would struggle to park a van in an actual parking lot, right?

Me too, now. And this asteroid is 200 million miles away. So it was pretty tricky. But they did it. It was October of 2020. You know, Osiris Rex got close to the surface. It briefly touched it with this robotic arm. At the end of the arm was a collection device.

We're going in. And the arm almost just like plunged in. deeper than they expected. So, you know, the surface of the asteroid was like this loose rubble. So, wow. So how much of the rock did they get then? Almost too much. And here's why I say that. So when the spacecraft backed away from the asteroid and they took some pictures of that collection device at the end of the robotic arm, what they saw was pebbles and particles and rocky material escaping out into space, just like floating away. And it turns out there was this flap that was supposed to close, a Mylar flap, and a rock had actually jammed into it.

And it was like open. There was this gap. Were the mission scientists freaked out? Oh, yeah. I mean, I was talking to Jason Dworkin. He's a scientist at NASA's Goddard Space Flight Center who works on the mission. He told me this moment was like gut wrenching. I'm a scientist.

I'm greedy. I want more. And I want absolutely full. and seeing those particles drifting away. Every particle is a discovery not made at PhD dissertation, not written. He says they really scrambled to seal the collection device and its rocks inside this canister. So the canister is what that return capsule brought to Earth. You know, basically the spacecraft flew by Earth and jettisoned this capsule, which came down to the surface.

And actually, the Osiris Rex spacecraft is going off to, you know, visit another asteroid. But we've got this capsule. the scientists have got the rocks. Okay, so in the end then, how much did they actually manage to collect from this asteroid? Like how much rock? So they won't know for sure until they count every little bit of it. But, you know, they estimate that it's about eight ounces, enough to fill a cup. Eight ounces?

That doesn't seem like a lot. Like a couple slices of cheese? It's actually a lot for a sample return mission from space. Oh, okay. I mean, Japan's space agency retrieved bits of a different asteroid. and, you know, they only brought back like five grams. Wow. And this is going to be like a couple hundred grams.

And actually, it's the most outer space stuff to be collected and brought home since the Apollo astronauts were bringing back moon rocks. Now, Nell, I have to ask, is there any chance that there's any alien life that might be hiding inside this asteroid sample? Nah, I mean, that is really just not a concern. The asteroid is not a cozy place. It's been hit by radiation for eons. And, you know, the mission scientists worked with NASA's planetary protection officer, and they determined there was just no danger of that at all. So they could bring it home without any special precautions. But the researchers are worried about Earth biology getting into the sample. They're worried that the sample will be contaminated by life here on Earth.

And that's why the capsule and the rocks inside were immediately put under this, like, nitrogen purge, this like flow of nitrogen gas to protect them from the Earth's atmosphere. And then the capsule was whisked away to NASA's Johnson Space Center in Houston where they have built this special lab just to receive these samples. And there's all these like cabinets and equipment there that'll let scientists study this rock without contaminating it with anything from Earth. And that's where they finally opened up the sealed canister, right? Right. So this canister has like the collection device inside that, you know, is the part that actually touched the asteroid. And so when they open it up, the first thing they see is kind of just like dust and stuff that's like around that. And, you know, the plan was to grab that dust and get it under the microscopes and analyze it right away and get some quick results back. Opening up the collection device that's like locked inside there, that's going to take some time.

Dworkin told me, you know, it's kind of a slow process. There are lots of fasteners that need to be removed. And so every screwhead could have been material inside of it. We've got to pluck out to preserve. So, you know, to get inside there and see the bigger rocks, the rocks that are more like pebbles or an inch or so across, you know, that'll be like days from now. But Loretta told me he's really excited to see the rock he thinks of as the troublemaker, you know, the one that propped open that flap and let stuff escape. They actually know which rock did that. We could see it and we're really excited to see it.

You know, first of all, just to say, you little, you know, but also just what is it? It must have been hard and different than probably the bulk of the after. And NASA is planning this big event on October 11th where they're going to share pictures and, you know, reveal basically what they found so far. I'm so excited to see that. Are there any other asteroid missions coming up? Absolutely. In fact, NASA is calling this it's asteroid autumn. You know, they've got to have some little catchphrase there. But in early October, there's the launch of the Psyche mission. So it's going to a metal-rich asteroid. It's not a sample return, but still cool, like metallic asteroid like. the inner core of a planet, you know, sort of like iron, nickel, metal. And then there's a spacecraft called Lucy that is on a mission to fly by a whole bunch of

asteroids. And it's going to pass by its first one, I think, in November. I can't remember the exact day, but November for sure. Okay. Thank you so much, Nell, for bringing us these stories. Oh, it's my pleasure. If you've been enjoying this episode, give us a follow on your podcast app. So you get alerted each time we publish a new episode.

And if you have any story ideas, send them our way. Our email is Shortwave at npr.org. This episode was produced by Burley McCoy and edited by our managing producer Rebecca Ramirez. Nell and Anil Oza checked the facts. The audio engineer was Robert Rodriguez. Beth Donovan is our senior director and Anya Grunman is our senior vice president of programming. I'm Regina Barber. Thanks for listening to Shorewave from NPR.