Short Wave

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...

In pop culture, squirrels are often seen as jerky, excited critters on the hunt for nuts to stuff themselves with and tuck away for later. But squirrels are on the hunt for something a bit meatier in the California Bay Area. Their target: local voles. The entire process — from hunt to kill — was captured on video. Want to hear more biology stories? Let us know by emailing shortwave@npr.org ! Liste...

In the early 20th century, a blight fungus wiped out most of the 4 billion American chestnut trees on the eastern seaboard. The loss was ecologically devastating. Short Wave host Emily Kwong dives deep into how scientists are trying to resurrect the American chestnut tree — and recent controversy over a plan to plant genetically modified chestnuts in the wild. Want to hear about more efforts to re...

On Christmas Eve, scientists at field stations across Antarctica sing carols to one another...via shortwave. On today's episode, the Short Wave podcast explores shortwave radio. We speak with space physicist and electrical engineer Nathaniel Frissell about this Antarctic Christmas Carol tradition and his use of shortwave radio for community science. Read more about Santa Net, which connects childr...

There are many statistics out there that prove that flying on a commercial airplane is safe, that plane crashes are overall pretty unlikely. Still, up to an estimated 40% of Americans feel some fear at the thought of flying. So, amid the travel rush of the holiday season, we ask MIT aeronautical engineer Mark Drela : How does a plane lift off and stay up in the air? Interested in more stories on p...

Towana Looney became the first living person in the world to get a kidney from a new kind of genetically modified pig last month. Health correspondent Rob Stein got exclusive access to be in the operating room. Towana is a 53-year-old grandmother from Gadsden, Ala. She's been on dialysis for four hours a day, three days a week since 2016. Her immune system would reject a human kidney. So the Food...

Old mines leave behind a a pressing problem: Huge holes that make the landscape look like a chunk of swiss cheese. But in Germany, some scientists and city planners are turning these into lakes. The largest one will be the biggest artificial lake in Germany when it's done, with a shoreline of 26 kilometers or about 16 miles all around. But it's not as easy as simply filling the holes with water. I...

AI uses a lot of power. Some of the next generation data centers may use as much power as one million U.S. households. Technology companies like Microsoft, Google, Amazon and Meta hope nuclear power will offer a climate solution for this energy use. Nuclear power plants can deliver hundreds of megawatts of power without producing greenhouse gas emissions. But some long-time watchers of the nuclear...

Racism is often covered as a political, cultural, or news story. But how is it affecting people's health? That's the question Cara Anthony , a KFF News reporter, wanted to answer: not just on an individual scale, but on a community-wide one. So for the past few years, she's been reporting on a small town in the Midwest that illustrates that health issue: Sikeston, Missouri. Today on the show, Cara...

The federal government has been tracking the weather for more than 150 years. Yet over the last few decades, the rise of the Internet and big tech have made weather forecasting a more crowded space. Today, our colleagues at NPR's daily economics podcast The Indicator report on the value of an accurate forecast and the debate over who should control weather data. Follow The Indicator on Apple Podca...

In the 1950s, scientists exposed a tin of meat to a dose of radiation that they expected would kill all forms of life. But one organism defied the odds and lived: Conan The Bacterium. Turns out this microorganism, known to science as Deinococcus radiodurans, is capable of surviving extreme levels of radiation — thousands of times the amount that would kill a human. So what's Conan's secret? Want m...

Thor. Loki. Heimdall. They're not just Norse gods or Marvel characters. They're also the names of various Asgard archaea . These microscopic organisms are found all over the world, from marine sediment to mud volcanoes to hydrothermal vents. A growing body of research suggests we owe them an evolutionary debt. This episode, Emily and guest host Jon Hamilton explore the wild world of archaea : Wher...