Science Friday

A new analysis of ancient footprints in New Mexico adds to the debate about when humans arrived in North America. Plus, astronomer Dean Regas offers tips for safe viewing of Saturday’s eclipse.

In 2021, scientists uncovered ancient human footprints in White Sands, New Mexico. Dating of the footprints suggested that people arrived in North America thousands of years earlier than anthropologists had thought. It sparked fierce debate among researchers, some of whom raised concerns about the radiocarbon dating process used in the original study. Now, a new study provides additional data supporting humans’ arrival in North America 22,000 years ago.

Ira talks with Maggie Koerth, editorial lead at Carbon Plan about the latest in this debate about the peopling of North America and other top science news of the week including how solar storms affect bird migration, why ants are getting ensnared in plastic, and how climate change is improving Bordeaux wine.

This Saturday, much of the continental United States will be treated to an astronomical event—an annular solar eclipse. In this type of eclipse, the apparent sizes of the moon and sun don’t align perfectly to Earth-bound viewers, resulting in a solar “ring of fire” shining around the edges of a moon nestled inside the boundaries of the sun.

The best viewing will come in a 125-mile-wide band known as the path of annularity, which will stretch from Eugene, Oregon to San Antonio, Texas, and then on into Mexico and Central America. Viewers outside that band will still be able to see some parts of the eclipse, with the percent coverage depending on how far they are from that central line.    

Even though the sun will be partly covered, it is NOT safe to look directly at the sun without eclipse glasses. If you don’t have glasses, you can look at a projection of the sun through a pinhole onto the ground or another surface—but don’t look through the pinhole at the sun. Astronomer and author Dean Regas joins Ira for an eclipse preview, and to offer viewing tips on when, where, and how to best view the solar event. 

To stay updated on all things science, sign up for Science Friday's newsletters.

Transcripts for each segment will be available the week after the show airs on sciencefriday.com.

Subscribe to this podcast. Follow our show on Instagram, TikTok, Facebook, and Bluesky @scifri and sign up for our newsletters. Got a science question that’s keeping you up at night? Call us: 877-472-4374

Hosted by Simplecast, an AdsWizz company. See pcm.adswizz.com for information about our collection and use of personal data for advertising.

As the Mississippi River drops to one of its lowest levels in recent history, the U.S. Army Corps of Engineers said salt water from the Gulf of Mexico could threaten drinking water as far north as New Orleans’ French Quarter if no action is taken.

On Friday, the Corps announced plans to avoid that scenario by building upon an existing underwater barrier that has been in place to block the progression of salt water from intruding farther upriver since July. At its current height, the Corps expects the salt water creeping up the bottom of the Mississippi River to overtop the barrier later this week, sometime around Sept. 22.

If that were to happen, the salt water would begin affecting drinking water in Belle Chasse by early October.

To read more, visit sciencefriday.com.

Beneath Kenya, the African tectonic plate is splitting in two. That cleave creates hydrothermal vents, ripe for harnessing geothermal energy. This is a renewable source of energy derived from hot water that bubbles up from deep underground. When it comes to the surface, it turns into steam. That steam can be used to spin a turbine connected to a generator, and voilá: electricity.

Kenya began to tap into this natural supply in the 1950s, and now the East African nation is the seventh largest geothermal energy producer in the world. The Kenyan government has said that the country’s untapped resources are enough to meet its peak energy demands five times over. That’s a big deal on a continent where more than 40% of people lack electricity.

Joining guest host Flora Lichtman to talk about this is Geoffrey Kamadi, a freelance science journalist based in Nairobi, Kenya. 

To stay updated on all-things-science, sign up for Science Friday's newsletters.

Transcripts for each segment will be available the week after the show airs on sciencefriday.com.

Subscribe to this podcast. Follow our show on Instagram, TikTok, Facebook, and Bluesky @scifri and sign up for our newsletters. Got a science question that’s keeping you up at night? Call us: 877-472-4374

Hosted by Simplecast, an AdsWizz company. See pcm.adswizz.com for information about our collection and use of personal data for advertising.

This past July, the 12th International Conference on HIV Science was held in Brisbane, Australia. But this wasn’t your typical scientific conference. Yes, findings were presented on the latest in HIV research, but it culminated in a museum exhibition.

12 HIV-positive artists were paired with 12 scientists, and each pair collaborated on a piece of art, largely based on the scientists’ research. One of the pieces attracted a bit more attention than the others.

Kairon Liu, an artist, curator, and photographer, and Kane Race, a professor of gender and cultural studies at the University of Sydney, wanted to create something that commented on the negative effects of global HIV policy and the current stigma of living with the disease. The resulting piece is titled Untransmittable, a transparent penis-shaped sculpture filled with thousands of expired antiretroviral pills.

Science Friday producer and Universe of Art host D. Peterschmidt sat down with Liu and Race to talk about the piece they made, why they couldn’t take it over the Australian border, and their hopes for future HIV research.

To stay updated on all-things-science, sign up for Science Friday's newsletters.

Transcripts for each segment will be available the week after the show airs on sciencefriday.com.

Subscribe to this podcast. Follow our show on Instagram, TikTok, Facebook, and Bluesky @scifri and sign up for our newsletters. Got a science question that’s keeping you up at night? Call us: 877-472-4374

Hosted by Simplecast, an AdsWizz company. See pcm.adswizz.com for information about our collection and use of personal data for advertising.

The latest trend in celebrity health care is full-body MRI scans, with influencers like Kim Kardashian endorsing them. These scans aren’t covered by health insurance, and run over $2,000 out of pocket. 

Typically, a new diagnostic tool is marketed to doctors and radiologists. But companies like Prenuvo are now marketing directly to consumers. They claim that their scans will catch early signs of cancer, aneurysms, liver diseases and even multiple sclerosis.

It’s an appealing promise. If you can afford it, wouldn’t it be nice to catch cancer super early? Could it even save your life? Unfortunately, it’s more complicated than that. Simply put, the potential harms far outweigh any possible benefits of such a scan. 

Guest host Flora Lichtman separates fact from fad with Dr. Rebecca Smith-Bindman, professor of epidemiology and biostatistics at University of California, San Francisco’s School of Medicine, and director of the Radiology Outcomes Research Laboratory, based in San Francisco, California.

To stay updated on all-things-science, sign up for Science Friday's newsletters. 

Transcripts for each segment will be available the week after the show airs on sciencefriday.com.

Subscribe to this podcast. Follow our show on Instagram, TikTok, Facebook, and Bluesky @scifri and sign up for our newsletters. Got a science question that’s keeping you up at night? Call us: 877-472-4374

Hosted by Simplecast, an AdsWizz company. See pcm.adswizz.com for information about our collection and use of personal data for advertising.

A news story was circulating a few months ago—a woman in Australia came into the hospital with abdominal pain. She was increasingly forgetful and struggling with depression. Her doctors were stumped for over a year. What was causing her symptoms? Turns out she had a three-inch parasitic worm living in her brain. They took it out, and she recovered.

How do doctors crack cases like this? How do you even know to check for a brain worm? This is the specialty of Dr. Joe DeRisi. When doctors run into a diagnostic dead end they call him. In his world, brain worms aren’t even that rare. (Ask him about brain-eating amoebas.)

Guest host Flora Lichtman talks with Dr. DeRisi, professor of biochemistry and biophysics at the University of California, San Francisco’s School of Medicine and president of the Chan Zuckerberg BioHub San Francisco, about his fascinating work solving some of the most vexing medical mysteries, and how it may even help detect the next pandemic-inducing pathogen. 

To stay updated on all-things-science, sign up for Science Friday's newsletters.

Transcripts for each segment will be available the week after the show airs on sciencefriday.com.

Subscribe to this podcast. Follow our show on Instagram, TikTok, Facebook, and Bluesky @scifri and sign up for our newsletters. Got a science question that’s keeping you up at night? Call us: 877-472-4374

Hosted by Simplecast, an AdsWizz company. See pcm.adswizz.com for information about our collection and use of personal data for advertising.

This week, a handful of scientists scattered around the world got surprise telephone calls announcing that they will be receiving Nobel Prizes. On Monday, the prize in medicine or physiology was announced. It went to Katalin Kariko and Drew Weissman, scientists who developed the modifications to mRNA that made the biomolecule a viable strategy for creating vaccines. On Tuesday, the Nobel in physics went to Pierre Agostini, Ferenc Krausz and Anne L’Huillier, who created techniques to illuminate the movement of electrons using attosecond-length pulses of light. And on Wednesday  Moungi G. Bawendi, Louis E. Brus and Alexei I. Ekimov learned that they had won the prize in chemistry for their work with tiny bits of semiconductor material known as quantum dots.

Umair Irfan, staff writer at Vox, joins guest host Flora Lichtman to talk about the winners and their advances, and to share other stories from the week in science, including an FCC fine for a satellite company’s space junk, concerns over drought in the Amazon rainforest, and a tale of fighting a coral-threatening algal bloom using hungry crabs.

Venus is an inhospitable place. The longest any spacecraft has survived on the planet’s surface is thought to be around two hours. It’s blazing hot. It has bone-crushing atmospheric pressure and clouds made of sulfuric acid. But is there lightning?

Flybys of Venus have detected electromagnetic signals in the radio spectrum called “whistler waves” that, on Earth, are associated with lightning strikes. So some experts speculated that Venus might have lightning too—perhaps a lot of lightning. But there was no hard proof. The question of Venusian lightning has been a topic of electric debate among scientists for some 40 years.

A study published in the journal Geophysical Research Letters last month used data from the Parker Solar Probe to argue that the whistler waves around Venus may have a different cause. Research scientist Dr. Harriet George and space plasma physicist Dr. David Malaspina of the Laboratory for Atmospheric and Space Physics at the University of Colorado, Boulder join guest host Flora Lichtman to talk about the finding, and what it could tell us about planets elsewhere in the galaxy.  

To stay updated on all-things-science, sign up for Science Friday's newsletters.

Transcripts for each segment will be available the week after the show airs on sciencefriday.com.
 

Subscribe to this podcast. Follow our show on Instagram, TikTok, Facebook, and Bluesky @scifri and sign up for our newsletters. Got a science question that’s keeping you up at night? Call us: 877-472-4374

Hosted by Simplecast, an AdsWizz company. See pcm.adswizz.com for information about our collection and use of personal data for advertising.

Earlier this month, a Food and Drug Administration panel concluded that a common decongestant ingredient used in drugs like Sudafed and NyQuil doesn’t work. The panel agreed that while the ingredient, called phenylephrine, isn’t dangerous, it doesn’t work any better than a placebo.

That made us wonder: How well do placebos work? And why do they work even when people know they’re getting a placebo?

Ted J. Kaptchuk, professor of medicine at Harvard Medical School and director of the Program in Placebo Studies and Therapeutic Encounter at Beth Israel Deaconess Medical Center, joins guest host and musician Dessa to talk about what’s new in placebo research. They discuss the benefits placebos can offer for chronic illness management, and when doctors might start using them in treatments.

With all the bad news on our feeds, a feel-good story can be a welcome reprieve. But what happens when that story comes in the form of coverage of disability technology?

You might’ve seen the videos online of a person with a physical disability being fitted with an exoskeleton, essentially “wearing” a robot, to help them walk. Onlookers cheer in the background, dramatic music swells, and we get the sense we’re watching something inspirational and empowering—a victory of the human spirit.

This might seem like a triumph of scientific innovation, but our guest asks us to look again at what’s actually going on in narratives like this one.

Dr. Ashley Shew, associate professor at Virginia Tech, studies the intersection of disability and technology and how our collective fixation on these fancy, supposedly transformative gadgets could be doing more harm than good. In her new book, she coins the term “technoableism” to get to the heart of the matter.Guest host and musician Dessa talks with Dr. Shew about her book Against Technoableism: Rethinking Who Needs Improvement, about what disability technology is, what the future should look like, and even how disability intersects with space travel and climate change.

Florida is known for citrus, particularly its fresh-squeezed orange juice. But citrus trees in the state are struggling. For the last two decades, crops have been struck with a devastating disease called “citrus greening.” And Florida orange production has dropped some 94% over that period.                                              

Citrus greening is caused by an invasive insect, the Asian citrus psyllid, which is threatening to wipe out the citrus industry in the state. One of the effects of the disease is a bitter, acidic fruit. Scientists are hard at work devising possible solutions to save Florida’s crop.

Guest host and musician Dessa talks with Dr. Yu Wang, associate professor of food science at the University of Florida’s Citrus Education and Research Center, about her recent advances in making infected orange plants sweeter.

When composer Sarah Hennies learned about a neurological theory called “motor tapes” from Oliver Sacks’ book Musicophilia, the concept stuck with her for years. The theory comes from neuroscientist Rodolfo Llinás, who posited that many of our thoughts, memories, and physical movements operate via a series of “looping tapes,” with the goal of reducing the amount of energy the brain uses while doing common, repetitive tasks.

The concept resonated with Hennies, who is also a visiting assistant professor of music at Bard College. Most of her compositions use heavy amounts of repetition, and Llinás’ theory fit with how she experienced her own memories and the evolution of her identity. Her piece “Motor Tapes” premiered in early August, performed by Ensemble Dedalus.

Hennies joins guest host and musician Dessa to talk about repetition in music, how to translate neuroscience into art, and what that pairing can reveal about our bodies and the world around us.

To stay updated on all-things-science, sign up for Science Friday's newsletters.

Transcripts for each segment will be available the week after the show airs on sciencefriday.com.

Subscribe to this podcast. Follow our show on Instagram, TikTok, Facebook, and Bluesky @scifri and sign up for our newsletters. Got a science question that’s keeping you up at night? Call us: 877-472-4374

Hosted by Simplecast, an AdsWizz company. See pcm.adswizz.com for information about our collection and use of personal data for advertising.

About a week ago, space nerds got the delivery of a lifetime: a sample from Bennu, an asteroid soaring through the galaxy, currently about 200 million miles away. The capsule of rocks and dust came courtesy of NASA’s OSIRIS-REx, the first U.S. mission to collect a sample from an asteroid.

Scientists hope it’ll help unveil some of the mysteries of our universe, like how the sun and planets came to exist or how life began. Guest host and musician Dessa talks with Sophie Bushwick, technology editor at Scientific American, about this week in science. They also chat about how antimatter interacts with gravity, the new RSV vaccine for pregnant people, why LED streetlights are turning purple, and how beetles came to dominate all other species, especially ants.

Ever try to take a picture of a spectacular moon that looks like it fills up half the sky? And then you look at the photo, and the moon looks like a tiny dumb ping-pong ball? And you want to march into the Apple store and demand to know why this pocket-size device fails to capture the wonder of the cosmos properly? 

The majesty of that supermoon you saw might be in your head as much as it is in the sky—your brain does a lot more than just receive data reports from your eyes. Vision is complicated. Seeing involves a lot of interpretation, of which you’re usually unaware. 

Guest host and musician Dessa talks with neuroscientist Dr. Cheryl Olman, associate professor in the University of Minnesota’s psychology department, about her work to better understand how the brain processes visual information using sophisticated fMRI techniques, including studying the brains of people with schizophrenia.

Jellyfish are known for their graceful, hypnotic movement through the water—and for occasionally stinging swimmers. One thing they’re not known for, however, is intelligence. A study published in the journal Current Biology, however, challenges the idea of the ‘brainless’ jellyfish by showing that at least one species of jelly may be capable of associative learning.

The scientists were studying the Caribbean box jellyfish, which normally lives amongst a forest of tangled mangrove tree roots. In the lab, they painted false roots on the walls of the jellyfish’s tank, and watched to see what happened. At first, the jellies judged the low-contrast gray roots to be far away, and tried to swim through them. After a few collisions with the tank, however, the jellies learned that the false roots were closer than they appeared, and learned to keep their distance.

Dr. Anders Garm, an associate professor of marine biology at the University of Copenhagen in Denmark, joins guest host Dessa to explain the experiment, and what it tells researchers about the connection between the behavior of small groups of neurons and the process of learning.

In 1933, a high schooler fishing along the Huron River in Ann Arbor, Michigan looked into the water and saw something weird. It turned out to be a freshwater jellyfish – the first ever discovered in the Great Lakes region. Later that year, there was another sighting in Lake Erie.

Researchers think the species hitched a ride here on aquatic plants shipped from China, then spread. But there’s no evidence they harm the lake ecosystems they now call home.

Since then, the jellyfish have spread across the Upper Midwest, loitering mostly in inland lakes, rivers, and streams. But we still don’t know all that much about them.

A biology professor and her field research class at Eastern Michigan University are hoping to change that. Every week, they slap on masks, snorkels, and floaties, and wade out into a southeast Michigan lake on the lookout for jellyfish.

Read the rest at sciencefriday.com.

To stay updated on all-things-science, sign up for Science Friday's newsletters.

Transcripts for each segment will be available the week after the show airs on sciencefriday.com.

Subscribe to this podcast. Follow our show on Instagram, TikTok, Facebook, and Bluesky @scifri and sign up for our newsletters. Got a science question that’s keeping you up at night? Call us: 877-472-4374

Hosted by Simplecast, an AdsWizz company. See pcm.adswizz.com for information about our collection and use of personal data for advertising.

This was a bad year for Florida’s coral reefs. Since the 1970s, reef cover in the Florida Keys has decreased by 90%. Those remaining reefs have been subjected to water temperatures higher than 100 degrees Fahrenheit, alongside other threats like disease and ocean acidification. This is a big problem for the largest reef in the continental U.S., which plays an important role in protecting the shorelines from erosion and storms.

Scientists are scrambling to preserve as much of the reef as possible. One method marine biologists are focused on is selectively breeding corals in labs. Scientists look for the specimens most resilient to heat stress, then breed them together to create hardy offspring. Those spawn are then implanted into the reef, with hopes of bolstering the existing structure.

Vox environmental reporter Benji Jones joins Ira to talk about his dives to Florida’s Pickles Reef, and the differences he saw between this year and last year. Then, Ira speaks with marine biologist Andrew Baker at the University of Miami about his efforts to bolster Florida’s reefs. 

Did you know that the ocean absorbs about a quarter of all CO2 emissions? And about 90% of excess heat? It’s the largest carbon sink we have—and one of our biggest allies in the climate movement.

Ira talks with Dr. Ayana Elizabeth Johnson, marine biologist and co-founder of the non-profit Urban Ocean Lab, as well as the climate initiative The All We Can Save Project. They chat about climate solutions—like the newly launched Climate Corps—the power of the ocean, and steps forward. Dr. Johnson is also the curator for Climate Futurism, an art exhibition at Pioneer Works in Brooklyn, New York.

This segment, originally from 2022, was re-aired this week.

Five years ago, Stephanie Barish was tired of the public’s attitude about climate change. “Most people at that time were just so negative about climate,” she said. “It was doom and destruction, and I thought, wow, to make positive change, you have to really look at this from a solutions perspective.” 

Stephanie is the founder and CEO of Indiecade, an organization that supports indie video game developers and hosts events like the Climate Jam—the goal of which was to change the gloomy public narrative around climate change. So, with the help of organizations like Earth Games, participants around the globe gather every year to make video games about climate change optimism, solutions, and justice.

Teams can also consult with subject matter experts, like Dargan Frierson, an associate professor of atmospheric sciences at the University of Washington, and also a judge for the Climate Jam. If teams wonder what climate change would look like on a different planet, they can go to him for answers. “We always look for scientific accuracy,” he said. “I think it’s very important to keep things within the realm of possibility, even when you’re looking at fiction.”

Read the rest at sciencefriday.com.

To stay updated on all-things-science, sign up for Science Friday's newsletters.

Transcripts for each segment will be available the week after the show airs on sciencefriday.com.

Subscribe to this podcast. Follow our show on Instagram, TikTok, Facebook, and Bluesky @scifri and sign up for our newsletters. Got a science question that’s keeping you up at night? Call us: 877-472-4374

Hosted by Simplecast, an AdsWizz company. See pcm.adswizz.com for information about our collection and use of personal data for advertising.

Climate Week NYC is wrapping up, where hundreds of events took place across the city (including one from Science Friday), all with the goal of encouraging conversation and action around our climate crisis.

The weeklong event takes place alongside the UN General Assembly meeting, where world leaders discussed climate change, alongside other topics, including the war in Ukraine and universal health coverage.

While President Biden emphasized the importance of reducing the use of fossil fuels to combat climate change, there was a notable absence of leaders from the world’s biggest polluters, including Biden and president Xi Jinping of China, from the meeting’s Climate Ambition Summit. UN Secretary-General António Guterres said that in order to participate, governments need to come with “credible, serious and new climate action.”

Large demonstrations also took place across the city, pressuring leaders and companies to take bigger action to end gas, oil, and coal use.

Swapna Krishna, a journalist based in Philadelphia, talks with Ira about these stories and more, including a new climate jobs program from the White House, a lawsuit from California against the five big oil companies, new battery recycling rules from the EU, and data from the Parker Solar Probe’s recent flight through a sun explosion.

A combination of factors led to Earth’s climate being able to support life. And changes in the climate some 6,000 years ago created the conditions for human civilization to flourish. It’s a delicate balance on the verge of collapse, due to our reliance on burning fossil fuels.

Ira talks with paleoclimatologist Dr. Michael Mann about his forthcoming book Our Fragile Moment: How Lessons from Earth’s Past Can Help Us Survive the Climate Crisis, about the importance of understanding our planet’s climate history, and strategies to get policymakers to take action before it’s too late to reverse some of the worst consequences of climate change.

Mann is a professor of earth and environmental science and director of the Penn Center for Science, Sustainability and the Media at the University of Pennsylvania, based in Philadelphia, Pennsylvania. 

Read an excerpt of the book on sciencefriday.com

How do you know that climate change is funny? Even the Antarctic ice sheets are cracking up.

The climate crisis is no joke, but that doesn’t mean we can’t laugh about it. Research suggests that comedy is a powerful way to connect people and get them to empathize with a cause—and the climate crisis is a pretty big one.

So what does science say about the power of a good laugh? And how does that fit into the climate movement?

Ira talks with Esteban Gast, comedian in residence at the clean energy non-profit Generation 180, and Dr. Caty Borum, executive director of the Center for Media & Social Impact at American University.

To stay updated on all-things-science, sign up for Science Friday's newsletters.

Transcripts for each segment will be available the week after the show airs on sciencefriday.com.

Subscribe to this podcast. Follow our show on Instagram, TikTok, Facebook, and Bluesky @scifri and sign up for our newsletters. Got a science question that’s keeping you up at night? Call us: 877-472-4374

Hosted by Simplecast, an AdsWizz company. See pcm.adswizz.com for information about our collection and use of personal data for advertising.