Please Explain (The Leonard Lopate Show)

Find out how photosynthesis works, and why it brings us beautiful fall foliage this time of year. Leonard talks to educator Dr. James Boyer and research scientist Dr. Amy Litt.

Weigh in: Where in the New York area have you spotted dramatic fall foliage so far this season?

An estimated 27 million people worldwide are afflicted with Alzheimer’s disease. Find out what Alzheimer’s is all about, and whether there are ways to prevent it or slow its progress. Dr. Richard Mayeux is co-director of the Taub Institute of Research on Alzheimer’s Disease and the Aging Brain at Columbia University Medical Center. Dr. Samuel Gandy is a neurologist at Mount Sinai.

Find out why mushrooms can be both delicious and dangerous. Gary Lincoff is author of several books including The Audubon Society Field Guide to North American Mushrooms. He’s also taught botany and mushroom courses at The New York Botanical Garden since the 1970s. Chef Jawn Chasteen of The Sea Grill is participating in the Mushroom Festival by Patina Restaurant Group.

Weigh in: Have you ever been mushroom hunting in the New York area?

What a week it’s been in the markets. Find out what’s behind the recent financial crisis of the past few days, and what the credit woes could lead to. Greg Ip is U.S. Economics Editor for the Economist; Andrew Caplin is an Economics Professor at NYU.

Happy 50th birthday to the microchip! On Please Explain, find out how microchips work, what they do for us in our everyday lives, and how far they’ve come since they were first introduced 50 years ago. Dr. Simha Sethumadhavan is Assistant Professor of Computer Science & Director of the Computer Architecture Laboratory at

Please Explain is all about satellites – find out what they are, how they work, and what role they play in your everyday life – from cellphones to the weather report. Dr. Christopher Small is a geophysicist at the Lamont-Doherty Earth Observatory of Columbia University; Dr. Scott E. Palo is a satellite engineer and Associate Professor of Aerospace Engineering Sciences at UC Boulder.

New York City generates about fifty thousand tons of garbage every day. Find out what's in New York City’s trash, how it gets taken out of the city, and where it's dumped! Benjamin Miller is a Senior Fellow at the CUNY Institute for Urban Systems and author of Fat of the Land: The Garbage of New York – The Last Two Hundred Years. Bob Gardener is Vice Director of the Landfill Management Division of the Solid Waste Association of North America and Senior Vice President with SCS Engineers based in Virginia.

From Spain to New York, jellyfish are becoming more numerous, and they’re showing up in places where they have rarely been seen before. Scientists say this explosion can be attributed to a combination of overfishing, rising sea temperatures, and pollution. Find out all about jellyfish, why they’re thriving, and whether their rise is signaling the ocean’s decline. Dr. Jennifer E. Purcell is a Marine Scientist at Shannon Point Marine Center and Adjunct Professor at Western Washington University; Dr. Monty Graham is Assistant Professor in the Department of Marine Sciences at University of South Alabama and Senior Marine Scientist at Dauphin Island Sea Lab.

Weigh in: Have you noticed more jellyfish than usual at NYC-area and NJ beaches? Has it affected your swimming habits?

Most Americans can’t see the Milky Way in the night sky…and here in New York, we’re lucky if we can see any stars at all! Find out why light pollution is a growing problem, and how it may even endanger your health. Leonard talks to Pete Strasser of the International Dark-Sky Association; and Dr. Richard Stevens, cancer epidemiologist and professor at the University of Connecticut Health Center.

Does New York City light pollution bother you? What are your tips for dealing with too-bright lights from the streets or from neighbors' homes?

Please Explain is all about muscles! Find out how they function, how to strengthen them, and how they can break down. Dr. E. Todd Schroeder teaches clinical exercise physiology at the University of Southern California.