Short Wave - It's Fat Bear Week!

Episode Date: October 6, 2023

Y'all, it's the most wonderful time of the year: Fat Bear Week! Brown bears in Katmai National Park and Preserve are putting on the pounds before they hibernate. During this time, their metabolism, heart and breathing rate slow way down and they recycle their waste internally. Today, we look at the cool (and peculiar) biological processes taking place during hibernation. Plus, we talk through some other science headlines we're obsessing over, including the light pollution from satellites and how gravity affects antimatter.Read a science headline you want to know more about? Email us 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, Shorewavers, Regina Barber here. With Aaron Scott. And Ari Shapiro. Ari is taking a break from hosting All Things Considered to chat with us for another shortwave roundup of science in the headlines. Thanks for being here. And I'm so, so delighted to join you. We're going to talk about how light from satellites could affect science and our safety.

How scientists are one step closer to understand an anti-matter mystery. And our pick for Fat Bear Week, plus some fun Fairfax. You're listening to Shortwave from NPR. Let's start with light pollution because that's something I'm familiar with. I think we've all heard about it from cities and houses, and now it's coming from satellites. Explain that. Yeah, satellites also cause light pollution because they reflect the sunlight. They look like stars and the night sky is filling up with them.

And that's because, of course, communication companies are promising reliable Internet to the most remote places by launching these networks of satellites. I mean, I'm sure that you've heard of Starlink from SpaceX. Yes, owned by Elon Musk. Yes. They currently have about 5,000 satellites in space with plans for thousands more. And that is just one company. The brightness from all these satellite networks can ruin data for ground-based telescopes.

And I spoke with observational astronomer Jeremy Treglone-Reed. He's a co-author on a new paper in nature focusing on measuring the brightness of the biggest commercial satellite in space, Blue Walker 3. He says, only seven stars in the sky are brighter. And for a sense of scale here, Blue Walker 3 is 64 times bigger than the first generation Starlink satellites. And AST Space Mobile, the company behind Blue Walker, wants to put up more of them. Beyond the impact for astronomers studying the cosmos and stargazers lying on a blanket

staring up at the sky, are there other implications? Yeah, fast internet doesn't just come at the cost of science. Some researchers are worried that these satellites might impact humanity safety. By falling out of the sky? No, but by what it gets in the way of. The light reflected by these satellites is making the night sky brighter, especially at dusk and dawn, which happens to be the time astronomers hunt for dim potentially dangerous asteroids. Yeah, so these bright satellites are interfering with our ability to find rogue space rocks.

Oh, no. Is there any effort to regulate this and prevent us from being crashed into by an asteroid? Yeah, all right, not from governments. There is a group made up of experts called the International Astronomical Union that does have recommendations for how bright these satellites can be without strongly affecting science. The union, of course, can't legally require companies to do anything, but they do lobby and they do a pretty good job working with industry so that they know how to modify future satellites.

Yeah, so SpaceX and AST SpaceMobile are already modifying satellites to be less bright, but it might not be enough. So Jeremy hopes that public pressure might help. Okay, let's move on to topic two, antimatter. This is taking us one step closer to solving one of the great mysteries of the universe. I'm intrigued. Yes, indeed. So scientists at CERN, the giant research facility in Europe, they have officially proven that antimatter obeysi, obeys the laws of gravity.

This is where I reveal, I don't actually know what antimatter is. I've heard the word, I've seen it in sci-fi movies. That's as far as it goes for me. Yeah, let me help you out. The universe we know of our planet, you, me, Aaron, were all made up of matter. But since the 1920s, scientists have known that every particle of matter, you know, protons, neutrons, electrons,

they have a corresponding antiparticle. And what sci-fi gets right is that when matter and antimatter collide, they explode and cancel each other out. So, Ari, this leads to our big mystery because scientists believe that at the beginning of the universe, there was both matter and antimatter. But instead of canceling each other out, the matter stuck around while the anti-matter vanished. We don't know what happened to it. But one fringe theory says that maybe gravity affects it differently and somehow pushed it out of the way. Now, Ari, the fringe idea totally contradicts Einstein's general theory of relativity.

So you can guess how scientists were betting. Not against Einstein. No, no. Jeffrey Hanks, who leads this collaboration that published this research in the journal Nature last week, he says they, of course, were thinking Einstein was right, but they couldn't know for sure until they tested it. Antimatter is this mysterious stuff. We don't know what happened in the origin of the universe. Gravity is another big mystery today. So it's very compelling to be able to do this experiment with two things that have big open questions.

What was the experiment? How did they test all of this? Yeah, so they use cutting-edge technology to make anti-hydrogen atoms like you do. And then they suspended them inside this magnetic force field in a very, very cold vacuum. Oh, just like a typical day at work, huh? At CERN, yeah. Then they turned off the magnetic field and they counted how many atoms fell due to Earth's gravity. And it turns out that 80% of these antimatter atoms fell, which matches the rate that normal atoms. fall. So antimatter behaves just like regular matter when it comes to gravity. And that means that

gravity likely doesn't explain what happened to all that antimatter at the dawn of the universe. So Einstein was right. And I'm picturing that famous photograph of him sticking out his tongue at his haters. Indeed. Indeed. How does he do it? All right. I may not understand antimatter, but I can understand a fat bear. Last but not least, tell us about Fat Bear Week. So this is an event started in 2014 by Rangers from Capmine National Park and Preserve in Alaska. It just kicked off on Wednesday. Think of it like an online March Madness tournament, except the winner is a very, very fat bear.

Yes, our competitors are 12 brown bears picked by Rangers, and these bears gather every year at Brooks River and Catmine to gorge on salmon beginning around late June, and they are all trying to do one thing, and that is get super fat to survive the coming winter hibernation. And just to give you a sense of how fat we're talking about, these adult male bears can grow from 700 pounds to 1,200 pounds. I looked at the website that has before and after photos, and the difference is shocking. It's incredible.

And that's because hibernation eats up a lot of weight. There is a lot that is going on is that bear slumbers. So, Ari, are you ready for some hibernation science facts? Never been more ready. Okay, number one. When hibernating, a bear's heart and respiratory rate drop dramatically. They average only one breath per minute with a heart rate of 8 to 10 beats per minute. Wow.

Bears don't eat, drink, urinate, or defecate while in their winter shelter or den. Instead, their fat is metabolized to produce water and food. So remarkably, bears are able to hold on to their muscle mass and bone density when they finally emerge from hibernation in the spring. Okay, I'm looking through the gallery, and I have to say it does not seem to be. fair to me that some of these bears get names like Chunk and Grazer and others have to settle for being Bear 901. How does the winner ultimately get picked? Yeah, so people go to fat bearweek.org and they vote on their favorite bear and the winner gets crowned next week on Fat Bear Tuesday. I'm all in on bear number 32, also known as Chunk. He has a, quote, low hanging belly and

ample hindquarters, unquote. That's what it says is hinge profile. Yes, ample hindrance. quarters on Hinchie. He also has my vote because he's described as enigmatic. But of course, they're all winners. This is just a fun way to bring more attention to these incredible bears and the cat my ecosystem. Well, as a responsible journalist, I'm not going to take sides in this debate. No, objectivity. Ari, thank you so much for hanging out with us. Anytime you want to talk fat bears, I'm here. 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.npr.org slash shorewave. This episode was produced by Burley McCoy and Gus Contreras. It was edited by Christopher Intaliata and Viet Le and our managing producer Rebecca Ramirez. Anil Oza Check the Facts. The audio engineer was Robert Rodriguez, Beth Donovan is our senior director, and Anya. Grundman is our senior vice president of programming. I'm Aaron Scott. And I'm Regina Barbara. Thanks for listening to Shortwave from NPR.