Short Wave

What do large crowds of people and water have in common? They both act like fluids. When crowds cheer, sway and clump together, the movements look like ripples of water. Researchers hope insights from physics like this one could help officials and engineers create safer crowds at festivals. Help shape the future of Short Wave by taking our survey: npr.org/ shortwavesurvey Listen to every episode o...

For a long time, microbes like the ones in Yellowstone's hot springs were studied in isolation. Molecular ecologist Devaki Bhaya says we should be studying them in community. Here's why. Help shape the future of Short Wave by taking our survey: npr.org/ shortwavesurvey Plus, if you liked this episode, check out our episode on the last universal common ancestor in the tree of life. Listen to every...

Black holes are notorious for gobbling up, well, everything . They're icons of destruction, ruthless voids, ambivalent abysses from which nothing can return — at least, according to pop culture. But black holes have another side: Astrophysicists have seen powerful jets, sometimes millions of light-years long, shooting out of supermassive black holes – including the one at the center of our own gal...

Ecologist Gergana Daskalova moved back to the small Bulgarian town of her childhood. It's a place many people have abandoned — and that's the very reason she returned. At the same time as land is being cleared around the world to make room for agriculture, elsewhere farmland is being abandoned for nature to reclaim. But what happens when people let the land return to nature? This episode, science...

In a world brimming with innovation and limited time, it can be hard to tell what technology has the potential to really shift life. Yet, every year, MIT Technology Review undertakes this very task and puts out an annual list to magazine readers of 10 Breakthrough Technologies . Today, host Regina G. Barber hops through highlights from the list with Amy Nordrum , an executive editor at the publica...

Farts are funny and sometimes smelly. But are they a legitimate topic of research? More than 40% of people worldwide are estimated to suffer from some kind of functional gut disorder — from acid reflux, heartburn, indigestion, constipation and irritable bowel syndrome to inflammatory bowel disease. So, yes, freelance science writer Claire Ainsworth thinks so. Claire speaks with Emily about two tea...

Bird flu, or avian influenza, is spreading among livestock and other mammals in the United States, raising concerns that another pandemic may be looming. Last month, California declared a state of emergency due to rising cases in dairy cattle, and there have been over 65 human cases in the U.S. during this outbreak. While cases have been largely mild and risk to the public is still considered low,...

Put on your headphones. In today's episode, host Emily Kwong leads us on a night hike in Patuxent River State Park in Maryland. Alongside a group of naturalists led by Serenella Linares , we'll meet a variety of species with unique survival quirks and wintertime adaptations. We'll search out lichen that change color under UV light and flip over a wet log to track a salamander keeping warm under we...

At least, it's contagious among a group of captive chimpanzees at the Kumamoto Sanctuary. How do researchers know? A very dedicated grad student at Kyoto University. In the quest for scientific knowledge, Ena Onishi logged over 600 hours in the field! This episode, host Regina G. Barber and special guests Jonathan Lambert and Ari Shapiro get into the nitty gritty of the research and their hypothes...

Around the turn of the century, 3.8 million people banded together in a real-time search for aliens — with screensavers. It was a big moment in a century-long concerted search for extraterrestrial intelligence. So far, alien life hasn't been found. But for people like astronomer James Davenport , that doesn't mean the hunt is worthless — or should be given up. No, according to James, the search is...

Forests are the lungs of our planet. Not only do they absorb carbon dioxide and create oxygen, they also regulate temperature, absorb rainwater to help prevent flooding and provide critical habitat for the majority of the world's land-based plant and animal species. But the trees that make up forests are increasingly endangered. Enter reforestation: replanting new forests to replace the old ones....

On Wednesday, the Food and Drug Administration announced it is banning the dye called Red No. 3, a food dye additive in many processed foods, like sodas, sweets and snacks. Recently, it and other dyes were linked to behavior issues in children. But high levels of Red No. 3 were linked to cancer in rats decades ago. So why is the ban happening now? Senior editor and science desk correspondent Maria...

Imagine the tree of life. The tip of every branch represents one species, and if you follow any two branches back through time, you'll hit an intersection. If you keep going back in time, you'll eventually find the common ancestor for all of life. That ancestor is called LUCA, the last universal common ancestor, and there is no fossil record to tell us what it looked like. Luckily, we have Jonatha...

When you picture a dinosaur, what does it look like? For Jingmai O'Connor , paleobiologist and associate curator of reptiles at the Field Museum of Chicago, the dinosaurs she studies look a lot more like birds. "If you looked at an artist's reconstruction of something like Velociraptor or Microraptor ... you would see that it pretty much looks the same as a bird," Jingmai says. "In terms of the pl...

The COVID-19 mRNA vaccine generates enough of an antibody response to protect against severe disease for six months. But other vaccines offer years-long — even lifelong — immunity, such as the measles or yellow fever vaccines. Is there a way for scientists to tell how long a person's immunity will last? A team at Stanford Medicine might have found a way to do just that — with the help of some of t...

Air quality in the Los Angeles region has plummeted due to smoke from the ongoing wildfires. With all that smoke comes possible risks to human health. So what actually is smoke and why is it so harmful? Jessica Gilman , an atmospheric chemist with the National Oceanic and Atmospheric Administration, explains what smoke is made of, how it behaves in the atmosphere and smoke's role in climate change...

Over 29,000 acres in the greater Los Angeles area are on fire right now. The fires emerged after the Santa Ana winds swept into the Los Angeles area Tuesday. The largest is the Palisades fire, which is quickly burning through the Pacific Palisades and Malibu communities. It's one of four ongoing critical fires — only one of which is partially contained. Ahead of the windy week, a Red Flag Warning...

Fluoridating the public water supply has been common practice for nearly 80 years in the U.S. It's an acclaimed public health intervention that helps prevent cavities. For just as long, some have raised concerns about the practice that can veer from evidence-based to unsubstantiated conspiracy. An analysis by government researchers, published Monday in JAMA Pediatrics , is adding to the debate. Th...

Some weapons used by the U.S. military are so powerful they can pose a threat to the people who fire them. Today, we meet two Marines, William Wilcox and Michael Lozano, who spent years firing missiles and rockets, then developed the same rare brain condition: arteriovenous malformation, or AVM. The condition sends high pressure blood from a tangle of abnormal blood vessels directly into fragile v...

There are hundreds of atomic clocks in orbit right now, perched on satellites all over Earth. We depend on them for GPS location, Internet timing, stock trading ... and space navigation? Today on the show, hosts Emily Kwong and Regina G. Barber learn how to build a better clock. In order to do that, they ask: How do atomic clocks really work, anyway? What makes a clock precise? And how could that...

Funeral services begin today for former President Jimmy Carter. He died Sunday, at 100-years-old. Carter brought attention to global health challenges, particularly "neglected" tropical diseases like Guinea worm. With reporter Jason Beaubien, we look at that decades-long effort and how science was central to Carter's drive for a better world. Questions or comments for us at Short Wave? Let us know...

(encore) Snowflakes. These intricate, whimsical crystals are a staple of magical wintry scenes, but how big can they really get? Well, according to the Guinness World Record keepers, the " largest snowflake " ever recorded was a whopping 15 inches in diameter. It was spotted near Missoula, Montana in 1887. But Kenneth Libbrecht , a physicist at Caltech, has long been skeptical of that record. So h...

Happy New Year, Short Wavers! What better time to contemplate the conundrum that is zero than this, the reset of the year? Zero is a fairly new concept in human history and even more recent as a number. It wasn't until around the 7th century that zero was being used as a number. That's when it showed up in the records of Indian mathematicians. Since then, zero has, at times, been met with some fea...

2024 was full of science news. There was a total solar eclipse, the Paris Olympics, elections in the United States and elsewhere, technological breakthroughs and many space launches. But perhaps above all, it was a huge year in health. So, today, we're talking through some of 2024's biggest health stories — from what's in our drinking water supply, to bird flu, obesity drugs and this year's record...

The thick-billed parrot is the only surviving parrot species native to the United States. These brightly colored birds once roamed across the American Southwest and as far south as Venezuela — but today, the only wild population remaining lives high in the forests of Mexico's Sierra Madre mountains. For years, conservation organizations like OVIS ( Organización Vida Silvestre ) and the San Diego Z...