Could aliens actually exist? Is there any chance they’ve visited Earth already? What really happened at Roswell? The truth... is right here. We talked to astronomers Dr. Jill Tarter, Dr. Seth Shostak, investigative journalist David Clarke, and physicist Prof. Jim Al Khalili.Check out the full transcript here: http://bit.ly/2PqOHRj Selected readings: Seth’s account of that day in 1997The “Condon report”-- a 1968 effort to go through and identify all UFO sightingsThe Roswell ReportThis paper estimating how many planets are in the “Goldilocks” zoneA good read on wormholes and their history; a tough read on how we might use them to teleportCredits: This episode has been produced by our senior producer Kaitlyn Sawrey, as well as Wendy Zukerman and Rose Rimler, with help from Shruti Ravindran and Meryl Horn. Fact checking by Michelle Harris and Meryl Horn. Music by Bobby Lord and Emma Munger. Editing by Blythe Terrell. Additional editing help from Caitlin Kenney. We performed this live for GimletFest - and we were joined onstage by our Aussie mate and mathematician Adam Spencer who has his own podcast you should check out ‘The Big Questions’, and astronomer Dr Emily Rice, who helps run Astronomy on Tap which brings together astronomers and beer. Check it out to see whether it runs in your city. Also thanks to Dr. Ravi Kumar Kopparapu, Dr. Craig O'Neill, Dr. Jessie Christiansen, Dr. Cameron Hummels, Dr. Phil Hopkins, Dr Avi Loeb, and the many other researchers who helped us on this.  Learn more about your ad choices. Visit podcastchoices.com/adchoices

This week, we’re entering the Lyme Wars. We’re asking: what is Lyme disease? How do you get it? How do you know you have it? And if you get infected, are you stuck with it forever? To find out we talk to neurologist Dr John Halperin, neuropsychology researcher Dr Kathleen Bechtold, and a Lyme patient we’re calling Emily.Check out the full transcript here: http://bit.ly/2DZhQxo Selected readings: About the culprits behind Lyme Disease The best summary on how well the Lyme tests workKathleen's study about patients suffering from Post-Treatment Lyme Disease SyndromeA most helpful primer on Chronic LymeTwo controlled trials showing that long-term antibiotics use doesn’t help zap out lingering Lyme symptoms Credits: This episode has been produced by Shruti Ravindran, with help from Wendy Zukerman, along with Rose Rimler and Meryl Horn. Our senior producer is Kaitlyn Sawrey. We’re edited by Blythe Terrell. Additional editing help from Caitlin Kenney. Fact checking by Michelle Harris. Mix and sound design by Emma Munger. Music written by Bobby Lord and Emma Munger. Recording assistance from Daniel Woldorff, Susan Valot, Davis Land and Julian Weller. For this episode, we also spoke to Dr John Aucott, Dr Brian Fallon, Dr Allen Steere, Dr Paul Lantos, Dr Adriana Marques and Dr Alan Barbour. Thank you so much. Thanks to the Zukerman Family and Joseph Lavelle Wilson. And our favorite songstress Rachel Ward. Learn more about your ad choices. Visit podcastchoices.com/adchoices

This week, we’re entering the foreskin firestorm. We’re asking: what are the risks of circumcision? And are there any medical benefits? To find out we talk to pediatric urologist Andrew Freedman, HIV researcher Godfrey Kigozi, and sex researcher Caroline Pukall.Check out the full transcript here: http://bit.ly/38leLWDSelected readings: The American Academy of Pediatrics technical report, which Andrew helped writeA thoughtful opinion piece from AndrewThe trial in Uganda that Godfrey co-authoredCaroline’s team’s penis-poking studyAnother paper from Caroline’s team on how men feel about their circumcisionsCredits: This episode has been produced by Rose Rimler, with help from Wendy Zukerman, along with Shruti Ravindran and Meryl Horn. Our senior producer is Kaitlyn Sawrey. We’re edited by Blythe Terrell. Additional editing help from Caitlin Kenney. Extra thanks to Soraya Shockley and Saidu Tejan-Thomas. Fact checking by Michelle Harris. Mix and sound design by Emma Munger. Music written by Bobby Lord and Emma Munger. Recording assistance from Gideon Brower, Ryan Delaney, Tom Wayne Harris, and Bahizi Ignatius. For this episode, we also spoke to Dr. Jenn Bossio, Dr. Aaron Tobian, and a bunch of folks at the CDC. Thank you so much. A special thanks to the parents and circumcised men who spoke with us for this story, as well as Frank Lopez, the Zukerman Family, and Joseph Lavelle Wilson. Learn more about your ad choices. Visit podcastchoices.com/adchoices

This week, how one of the worst ideas in science got a big push from a bad study… and intellectuals of the day lapped it up. We speak to science writer Carl Zimmer and Prof. J. David Smith, whose research helped get to the bottom of this disturbing story.UPDATE 05/25/18: This episode has been updated. A previous version said that the 'good' side of the Kallikak family included someone who had signed the Declaration of Independence. It now says that the 'good' Kallikak family member married into the family with the relative who signed the Declaration of Independence.Check out the full transcript here: http://bit.ly/2sak22yTo find a list of our sponsors and show-related promo codes, go to gimlet.media/OurAdvertisersSelected readings: Carl Zimmer's book 'She Has Her Mother's Laugh' Henry Goddard’s book about the Kallikak familyJ. David Smith’s article on the truth about Emma’s familyThe sad story of Carrie Buck and forced sterilization This episode was produced by senior producer Kaitlyn Sawrey, Wendy Zukerman, Romilla Karnick with help from Meryl Horn, Rose Rimler, and Shruti Ravindran. We’re edited by Blythe Terrell, extra editing help from Alex Blumberg and PJ Vogt. An extra thanks to Phoebe Flanagan as well as Emily Ulbricht for help with German translations. Fact checking by Michelle Harris and Meryl Horn. Mix and sound design by Emma Munger. Music written by Bobby Lord and Emma Munger. Thanks also to Professor Peter Visscher, the Zukerman Family and Joseph Lavelle Wilson. Learn more about your ad choices. Visit podcastchoices.com/adchoices

We have this idea that polar bears are teetering on the brink of extinction. But the story isn’t that simple. To find out why, we talk to environmental lawyer Kassie Siegel, wildlife biologist Dr. Karyn Rode, and sea ice expert Dr. Ignatius Rigor. With a little help from Payton, a polar bear at the Memphis Zoo.Check out the full transcript here: http://bit.ly/2qv9n1t Selected readings: This map of polar bear populations around the ArcticOn the Endangered Species Act and global warmingKaryn’s tale of two bear populationsThis paper on Arctic sea iceThis episode was produced by Wendy Zukerman, senior producer Kaitlyn Sawrey, and Heather Rogers, will help from Rose Rimler, Shruti Ravindran, and Meryl Horn. Extra help from Saidu Tejan-Thomas. We’re edited by Blythe Terrell, extra editing help from Caitlin Kenney. Mix and sound design by Emma Munger. Music written by Bobby Lord and Emma Munger. Recording help from Peter Frick-Wright, Amber Cortes and Katy Sewall. A huge thanks to all of sea ice and polar bear researchers that we contacted for this story, including: Dr Walt Meier, Professor Kent Moore, Dr Ian Stirling, James Wilder, Anthony Pagano, and Dr Peter Boveng. And more thanks to Danielle Brigida, Frank Lopez, Gerald Thompson, the Zukerman Family and Joseph Lavelle Wilson. Learn more about your ad choices. Visit podcastchoices.com/adchoices

This week, something different. We speak to astronaut Scott Kelly, who went up to space a man and came back a Rhesus monkey. Just kidding, that didn’t happen at all. Listen to find out the real story. PLUS: We talk to Lynn Levy, star producer of the Gimlet show The Habitat.Check out the full transcript here: http://bit.ly/2LEvaf7 Selected readings:NASA’s updated press release about Scott and MarkMore information about its Twins StudyA paper about what space does to your eyeballsThis episode has been produced by Romilla Karnick, Wendy Zukerman, and senior producer Kaitlyn Sawrey, with help from Rose Rimler and Shruti Ravindran. We’re edited by Blythe Terrell. With additional help from Lynn Levy and Peter Bresnan. Fact checking by Michelle Harris. Mix and sound design by Emma Munger. Music written by Bobby Lord and Emma Munger. Recording help from Mark Bramhill. Extra thanks to Susan Bailey, Alan Hargens, Chris Mason, the Zukerman Family and Joseph Lavelle Wilson.  Learn more about your ad choices. Visit podcastchoices.com/adchoices

People who love the ketogenic diet swear it boosts their brainpower, melts their fat, and makes them better athletes. Is it true? To find out, we go keto. And, we talk to some scientists: neuroscientist Dom D’Agostino, medical researcher Eric Verdin, and nutritionist Louise Bourke. Also, Wendy’s mum drops in.Check out our full transcript here: http://bit.ly/355sUF7 Selected readings:This history of the ketogenic dietA pretty comprehensive reviewEric’s exploration of keto on the memories of miceLouise’s paper on keto and sportsThis episode has been produced by senior producer Kaitlyn Sawrey with help from Wendy Zukerman along with Rose Rimler, Shruti Ravindran and Romilla Karnick. We’re edited by Blythe Terrell. Additional help from Eric Menell and Simone Polanen. Fact checking by Michelle Harris. Mix and sound design by Emma Munger. Music written by Bobby Lord. Recording help from Marissa Shieh and Mary Shedden. Extra thanks to Professor Jon Ramsey, Professor Judith Wylie-Roset, Professor Clare Collins, Dr Deirdre K Tobias, Joanna Lauder and Frank Lopez. Thanks to Jack Weinstein. And extra special thanks to Joseph Lavelle Wilson and Ingrid Zukerman. Learn more about your ad choices. Visit podcastchoices.com/adchoices

Nine countries, including North Korea, have nuclear weapons. What would happen if a nuclear bomb was dropped-- say, in New York City? We talk to nuclear historian Dr. Alex Wellerstein, nuclear engineer Dr. Tetsuji Imanaka, and epidemiologist Dr. Eric Grant.UPDATE 04/27: We've adjusted this episode to correct the elevated risk of cancer in survivors of the Hiroshima and Nagasaki nuclear bombs. If you survived the atomic bombs your risk of cancer is 10% higher than someone who is the same age as you.Check out our full transcript here: http://bit.ly/2salOAK Selected readings:Alex’s nuclear weapon simulation websiteTetsuji’s paper calculating the radiation exposure of Hiroshima survivorsThis review of the Life Span Study of atomic bomb survivors This sobering report on nuclear winterTo find a list of our sponsors and show-related promo codes, go to gimlet.fm/sponsorsThis episode has been produced by Heather Rogers, Wendy Zukerman, our senior producer Kaitlyn Sawrey, Rose Rimler, and Shruti Ravindran, with help from Romilla Karnick. We’re edited by Blythe Terrell. Additional thoughts from Lulu Miller. Fact checking by Michelle Harris. Mix and sound design by Emma Munger. Music written by Bobby Lord and Emma Munger. Thanks for recording help from John Wild. For this episode we also spoke to Prof. Richard Wakeford, Dr. Richard Turco, Prof. Brian Toon, Prof. Alan Robock, Dr. Dale Preston, Dr. William Kennedy, Dr. Jonathan D. Pollack, and a bunch of other experts on North Korea and nuclear weapons. Thank you so much. Also, special thanks to Shigeko Sasamori and Kathleen Sullivan. An extra special thanks to the Zukerman family and Joseph Lavelle Wilson. Learn more about your ad choices. Visit podcastchoices.com/adchoices

Harvey Weinstein and Kevin Spacey are said to have it. You probably have a friend who says they have it too. But is sex addiction the refuge of scoundrels? Or is it a real psychological problem? We speak to sex therapist Dr. David Ley, clinical psychologist Dr Shane Kraus, neuroscientist Dr. Nicole Prause, and someone we call Jeff.If you are experiencing troubles related to sex, you can look for support here.Check out our full transcript and its beautiful thickets of footnotes: http://bit.ly/2rvVfWDTo find a list of our sponsors and show-related promo codes, go to gimlet.fm/sponsorsThis episode has been produced by Shruti Ravindran, with help from Wendy Zukerman, along with Rose Rimler, Heather Rogers and Romilla Karnick. Our senior producer is Kaitlyn Sawrey. We’re edited by Blythe Terrell. Additional editing help from PJ Vogt. Fact checking by Michelle Harris. Mix and sound design by Emma Munger. Music written by Bobby Lord. Recording help from Gideon Brower and Hannah Colton. For this episode we also spoke to Dr. Marc Potenza, Dr. Carl Erik Fisher, Dr. Valerie Voon, Dr. Joshua Grubbs, and Dr. Mateusz Gola. Thank you so much for your help. And an extra special thanks to Frank Lopez, Joel Werner, Joseph Lavelle Wilson, and to all the men and women who allowed us to hear their stories in meetings for sex addicts and sexual compulsives in New York.Selected readings:  Shane’s review paper on the case for sex addiction Shane’s survey on sex addiction among veteransA review paper critiquing the case for sex addictionNicole’s lab study testing whether sex addicts can control sexual response Learn more about your ad choices. Visit podcastchoices.com/adchoices

America’s got an opioid problem. So where do we go from here? What can actually help people struggling with opioid addiction? We speak to Dr. Anna Lembke, Dr. Marvin Seppala, and a patient we call Mischa.UPDATE 04/17: We’ve adjusted a couple of lines of script in this episode to clarify the role of religion in Alcoholics Anonymous and Narcotics Anonymous. A previous version of this episode incorrectly implied that the 12 step philosophy considers addiction a sin and a “defect of character”.If you or someone you love is struggling with an opioid addiction, in the US you can call the Substance Abuse and Mental Health Services Administration's National Helpline: 1-800-662-HELP or visit their website.Check out our full transcript: http://bit.ly/2LB4kEoTo find a list of our sponsors and show-related promo codes, go to gimlet.media/OurAdvertisersThis episode has been produced by Rose Rimler with help from Wendy Zukerman, along with Shruti Ravindran and Romilla Karnick. Our senior producer is Kaitlyn Sawrey. We’re edited by Blythe Terrell. Additional editing help from Lulu Miller. Fact checking by Michelle Harris. Mix and sound design by Emma Munger. Music written by Bobby Lord. Recording help from Marissa Shieh and Julia Smith. For this episode we also spoke to Dr. Hilary Connery, Dr. Ben Davies, Prof. Linda Gowing, Dr. Laura Payne, Prof. Suzanne Nielsen, Prof. Tom McLellan, and Prof. Wayne Hall. Thank you so much for your help. And special thanks to the Rimler family, Devon Taylor, Sarah McVeigh Joseph Lavelle Wilson, and to everyone who spoke with us about their personal experiences with addiction and treatment.Selected readings: The White House report on combating drug addiction This study that followed about 150 people in NA This review on buprenorphine and other medicationsThis review on risk of death This survey that asked doctors what stopped them from prescribing buprenorphine Learn more about your ad choices. Visit podcastchoices.com/adchoices