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What urban design tells us about democracy Apr 24, 2026

Show notes

The way ancient societies like the Greeks, Maya, and Khmer Empire built their cities can tell us a lot about how a place was governed. Did rulers live in ornate palaces or alongside other residents? Are there large, open spaces for community gatherings?

In a new study, archaeologists document how they use the design of ancient temples, plazas, and cities to understand how a society was governed. So what does ancient architecture reveal about democracy? And do the democratic design principles hold true today?

Host Flora Lichtman chats with anthropologist Jake Holland-Lulewicz about ancient democracies, and with archaeologist Jeff Hou about how the role of public spaces in democracies has changed.

Guests:

Dr. Jacob Holland-Lulewicz is an anthropologist and assistant professor at Penn State.

Dr. Jeff Hou is the head of the architecture department at the National University of Singapore.

Other episodes you may enjoy:

Transcripts for each episode are available within 1-3 days at sciencefriday.com .

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Listening for the cosmic ‘dark ages,’ from the lunar far side Apr 23, 2026

Show notes

What did the universe look like before any stars turned on? Astronomers call that time the “dark ages,” and while they think it may be possible to see remnants of it in very low frequency radio signals, hearing those signals from Earth can be challenging.

One possibility is to put a radio telescope on the far side of the moon, where it would have periods of observation shielded from interference both from Earth and from the sun—and potentially be able to receive that dark ages signal. The LuSEE-Night mission will explore that approach. A small demonstration radio telescope is slated for launch in late 2026 to serve as a proof of concept for low frequency radio astronomy on the lunar far side.

Astronomer Anže Slosar, lead scientist for LuSEE-Night, joins Host Ira Flatow to describe the telescope project and what astronomers hope to achieve by sending it to the moon.

Other episodes you may enjoy:

Guests:

Dr. Anže Slosar is science lead for the LuSEE-Night project. He’s based at Brookhaven National Lab.

Transcripts for each episode are available within 1-3 days at sciencefriday.com .

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How do you describe nature? Two poets help us Apr 22, 2026

Show notes

To mark Earth Day, we asked you to tell us about your favorite places on the planet. You took us to the woods near Traverse City, Michigan, to a lake in Oklahoma, to Long Island Harbor where you spent your summers as a kid.

Basking in a sea breeze and admiring a sunset are basic human pleasures. But how do you take these moments and turn them into meaning? How do you pin those feelings down with words?

Joining Host Flora Lichtman are two poets who make that attempt for their livelihood: Jane Hirshfield, founder of Poets for Science, and Kimberly Blaeser, founding director of Indigenous Nations Poets and former Wisconsin poet laureate.

Guests:

Kimberly Blaeser is a poet, founding director of Indigenous Nations Poets, and former Wisconsin Poet Laureate.

Jane Hirshfield is a poet, essayist, and translator. She is the author of “Ledger” (Knopf, 2020) and nine other books of poetry. She’s based in San Francisco, California.

Transcripts for each episode are available within 1-3 days at sciencefriday.com .

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The lucky breaks that make our Earth home Apr 21, 2026

Show notes

What makes Earth special, and why are we here at all? In his book “Why Do We Exist? The Nine Realms of the Universe That Make You Possible,” astrophysicist Hakeem Oluseyi tackles the conditions needed to put life on Earth, from the formation of stars, to self-organizing molecules, to quantum weirdness and the nature of time. He joins Host Flora Lichtman to celebrate our place in the cosmos.

Read an excerpt from "Why Do We Exist?"

Guest:

Dr. Hakeem Oluseyi is an astrophysicist and author of “Why Do We Exist? The Nine Realms of the Universe that Make You Possible.”

Transcripts for each episode are available within 1-3 days at sciencefriday.com .

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How New Jersey tamped down PFAS in drinking water Apr 20, 2026

Show notes

Nearly all Americans have some type of PFAS, commonly known as “forever chemicals,” in their blood. The chemicals, which are linked to numerous health issues, were first regulated in drinking water at the federal level two years ago (though some limits have been rolled back).

But, back in 2018, New Jersey became the first state to adopt its own drinking water standards for PFAS. Now, researchers at Rutgers University have crunched the data to see how well it worked. They found that levels of the regulated chemicals dropped by as much as 55%.

Host Ira Flatow talks with the lead author of the study, cancer epidemiologist Hari Iyer about the significance of his findings and his plans to study the possible link between PFAS and prostate cancer.

Want to filter PFAS from your tap at home? Learn more:

Identifying Drinking Water Filters Certified to Reduce PFAS via EPA
Home Water Treatment for PFAS via PennState Extension

Guest:

Dr. Hari Iyer is an assistant professor of cancer epidemiology and health outcomes at the Rutgers Cancer Institute of New Jersey.

Transcripts for each episode are available within 1-3 days at sciencefriday.com .

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How a particle accelerator illuminated 56 human organs Apr 17, 2026

Show notes

A new imaging technique using a particle accelerator is giving researchers an unprecedented level of detail of our organs, producing scans 100 billion times brighter than a CT scanner. Those 3D models are now part of a public database called the Human Organ Atlas, available to researchers and the medically curious.

Joining Host Ira Flatow to explain why they needed so much power and what kind of research advances will follow is imaging scientist Claire Walsh, director of the Human Organ Atlas hub.

Check out images from the Human Organ Atlas on our website.

Guest:

Dr. Claire Walsh is an associate professor at the UCL department of mechanical engineering and director of the Human Organ Atlas Hub.

Transcripts for each episode are available within 1-3 days at sciencefriday.com.

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Simone Giertz’s journey from robot comedy to high-end design Apr 16, 2026

Show notes

In the 2010s, inventor Simone Giertz (pronounced “Yetch”) began making videos that straddled the line between practical and absurd. What if you had a robot that could feed you soup? Or a drone that could cut your hair? As time went on, her projects became more polished and more ambitious, like converting a Tesla sedan into a pickup truck.

Today, with almost 3 million subscribers to her YouTube channel, Simone is still designing and building objects that are quirkily useful—a fruit bowl that changes size for instance—but that could also be at home in a high-end design store. She joins Host Flora Lichtman to talk about her approach to problems, and the joy of making physical objects in an increasingly online world.

Guest:

Simone Giertz is an engineer, maker, YouTube creator and founder of Yetch Studio.

Transcripts for each episode are available within 1-3 days at sciencefriday.com .

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When a dolphin whistles, what does it mean? Apr 15, 2026

Show notes

What are dolphins actually saying with their iconic, high-pitched whistles? Dolphin communication researcher Laela Sayigh is trying to find out. She’s been compiling a database of whistles from a pod of dolphins in Sarasota, Florida, the longest-studied group of cetaceans in the world.

She joins Flora to discuss fundamental questions about dolphin dialects, including how dolphins’ “signature” whistles can change depending on context, and the process of decoding new types of whistles.

Guest:

Dr. Laela Sayigh is a senior research specialist at the Woods Hole Oceanographic Institution.

Transcripts for each episode are available within 1-3 days at sciencefriday.com.

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Inside the lives of astronauts’ families Apr 14, 2026

Show notes

“This was not easy, being 200,000+ miles away from home. Like before you launch, it feels like it's the greatest dream on earth. And when you're out there, you just wanna get back to your families and your friends.” – Artemis II Commander Reid Wiseman

Last week, the crew of Artemis II made it safely home. Throughout the journey, we heard the astronauts talk about moonjoy, awe, wonder, and—without exception—gratitude for their families.

To learn more about what it's like to be part of an astronaut family, Host Flora Lichtman chats with Tracy Scott, whose dad was a commander during the Apollo missions. Now, as a sociologist who studies the Moonshot era, Scott gives us a glimpse into astronaut life and the social context of the Apollo and Artemis missions.

Guest:

Dr. Tracy Scott is a sociologist at Emory University studying the lives and families of Apollo era astronauts. She’s based in Atlanta, Georgia.

Transcripts for each episode are available within 1-3 days at sciencefriday.com .

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Green stuff, brown stuff: Secrets to a great compost pile Apr 13, 2026

Show notes

If you’re a gardener, thinking about getting your soil in shape probably means thinking about compost. But composting can be a mysterious process. What can go into the pile? How do you balance carbon and nitrogen? And how do you do it in a city?

Compost expert Cassandra Marketos joins Host Ira Flatow to break down the basics of what she calls “purposeful decomposition,” and give practical tips for the backyard composter.

Read an excerpt from Marketos’ new book, “Compost after Reading.”

Guest:

Cassandra Marketos is the author of “Compost After Reading: A Practical Manifesto for Purposeful Decomposition.”

Transcripts for each episode are available within 1-3 days at sciencefriday.com.

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