Dr Tracy Becker tells us about solar system science using ultraviolet light. She explains how the color of a planet's northern lights depends on the planet's atmosphere. She also describes how scientists repurposed the New Horizons spacecraft to measure how empty space is.

Professor Thomas Tauris explains what gravitational waves can tell us about colliding neutron stars. He corrects Carrie's misconception about how gravitational waves affect people. He also explains how the last 400 years of astronomy have been like watching a silent movie, but now with gravitational waves, we have a soundtrack. 

Loren Grush talks about her new book, "The Six: The Untold Story of America's First Women in Space." She explains why Sally Ride was chosen to be the first American woman to go to space, and how the resulting attention was difficult for her. Loren also tells us how she researched and wrote the book during the pandemic.

Dr. James Tuttle Keane discusses why Pluto probably has a huge underground ocean. To make this discovery, he used images of Pluto taken by the New Horizons spacecraft, computer simulations, and good old-fashioned pen and paper.

Dr. Barbara Cohen returns to the show to talk about meteorite collecting in Antarctica. These trips, which involve weeks of camping on the ice, provide invaluable scientific samples. She talks about what it's like to search for the rocks that "don't belong" in the frozen desert.

To celebrate Earth Day, Dr. Kate Marvel talks about models of Earth's climate. She compares many models to learn more about the way our climate works, and how it might change in the future. She also offers advice for those of us who may feel overwhelmed by climate change.

Dr. Patrick Michel talks about comet 67P/Churyumov–Gerasimenko, which was visited by the Rosetta spacecraft. This comet's shape was puzzling. It looked like it had survived a collision, but how could a fragile icy comet survive a high-energy impact? A new study by Dr. Michel and his team sheds light on this mystery.

Dr. Miho Janvier talks about her work studying solar storms, and tells us about the ways these storms have impacted humans in the past. She explains why they are challenging to model and says why she's interested in "garbage" data from planetary missions.

Chase Childs tells us about satellite remote sensing. He explains how near-infrared images can expose underground structures, and why plant health is of surprising interest to archeologists. He also talks about GlobalXplorer, and some of the site's power users who have painstakingly mapped Peru.

Dr. Sarah Parcak explains how she uses satellite images to locate archeological sites, and how it's her job to be a detective, piecing together clues to uncover the past. She also talks about GlobalXplorer, a non-profit that lets everyone be a space archeologist.

Dr. Jeff Rich returns to the show to talk about the interstellar medium— all the rocks, dust, and particles that exist between the stars. After some beer, we end up talking about black holes and how Jeff studies nearby galaxies to learn about the early universe.

Dr. Kelly Fast tells us about the Planetary Defense Coordination Office, which finds asteroids before they find us. She talks about a recent exercise involving the tiny asteroid 2012 TC4, where asteroid hunters across the world coordinated to observe this object on a recent fly-by. We also talk about ‘Oumuamua, the first interstellar asteroid ever discovered.

Dr. Mark Panning tells us all about “earthquakes” on other worlds. He talks about the InSight mission to Mars, which carries a seismometer to detect Marsquakes. He also explains how a seismometer on Europa could teach us about the interior of that icy moon.

We hear from Dr. Diana Blaney, the principal investigator of the mapping imaging spectrometer on Europa Clipper. Europa Clipper will travel to Jupiter to see if its moon Europa is habitable. She describes how they tested the spectrometer in special rooms to make sure it will work at Europa.

Mario Cabrera tells us about the specialized detectors used in professional telescopes. He talks about how he’s helping to develop new detectors that don’t require coolant and provide more science for less money. He talks about the ways a detector is tested, and how he’s walked through miles of waist-deep snow (both ways!) in the name of science.

Dr. Jonah Kanner talks about LIGO’s spectacular detection of two neutron stars merging together. This merger was not only detected by gravitational wave detectors in the US and Europe, it was also seen by many telescopes across the world and in space. This new discovery will help unlock many longstanding mysteries in astronomy and fundamental particle physics.

Cassini’s spacecraft operations team manager, Julie Webster, stops by the show to reflect on Cassini. We chat about the time Cassini dove through Titan’s atmosphere, how Julie monitored thousands of channels of telemetry at once, and how she’s happy that she doesn’t have to spend her time thinking through worst-case scenarios (or “awfulizing”) now that the spacecraft is no more.

Dr Morgan Cable returns to the show to chat about the end of the Cassini Mission. We find solace in the fact that there’s still a tiny bit of Cassini in orbit around Saturn. Dr. Cable also describes Cassini’s discovery of hydrogen, “the easiest food for a microbe to digest,” in Enceladus’ plumes.

Sagan Prize winner Dr. Henry Throop tells us how scientists look for micron-sized dust that’s millions of miles away to protect the New Horizons spacecraft. This search involves computer modeling, occultation observations, and plenty of teamwork.

Dr. Fengchuan Liu talks to us about an international project, the Thirty Meter Telescope (TMT). He describes the telescope, it's many mirrors, and how he helps manage such a complex project.

Dr. Cindy Hunt returns to the show to talk about the upcoming 100th anniversary of the 100 inch Hooker Telescope on Mount Wilson. She explains why this telescope looks like a battleship and tells us how it “completely upended our understanding of the universe”. Also: poetry!

Dr. Lisa Storrie-Lombardi returns to the show to discuss NuSTAR, Spitzer, and what it feels like to end a mission you’ve been working on for decades. Cassini’s Grand Finale has us reflecting on the upcoming demise of the Spitzer Space Telescope.

Professor Jay McMahon stops by the show to explain the YORP effect and how it changes asteroid spins and shapes. He also describes his NASA Institute for Advanced Concepts (NIAC) project that is investigating the use of soft robots to explore rubble-pile asteroids.

Dr. Mary Peterson tells us about basaltic glasses from the Galápagos Islands, and why they might have originated deep within the Earth’s mantle. She also describes her lab work, which involves cool lab coats, security badges, and meticulous sorting of samples.

Professor Lamiya Mowla tells us about an exciting JWST discovery. She describes gravitational lensing as "nature's magnifying glass." She also explains why she likes calling telescopes time machines. We discuss pretty and shiny things, and why prettiness might indicate something is scientifically interesting.

Dr. Andrea Donnellan stops by the show to talk about GeoGateway, a website that combines different datasets to help geologists. She explains how rocks move like silly putty, and recounts the time a lone cloud masqueraded as tectonic motion.

Bonus music at the end is “Glorious Dawn” by Colorpulse. Hear more rad science tunes at www.symphonyofscience.com.

Dr. Emily Kramer stops by the show to try some tea and talk about her trip to South Africa to observe the next New Horizons target, 2014 MU69. She was one of several astronomers and planetary scientists who flew to other countries to watch this object pass in front of a star in the hopes of measuring its diameter.

Dr. Quan-Zhi Ye tries an unusual frappuccino and explains how meteor showers are related to comets. He tells the story of how he became interested in comets and asteroids, and fills us in on some of his recent research.

Dr. Jessie Christiansen returns to the show to talk about newly discovered exoplanets! She explains why this planetary system was devilishly difficult to observe with ground-based telescopes, and how one of the planets poses a puzzle.

Dr. Raymond Francis talks about a rock-vaporizing laser and the software that controls it. He describes how he and colleagues programmed a computer to make choices like a geologist would, allowing the Curiosity rover to do more science on Mars.

Dr. Bethany Ehlmann returns to talk about Ceres. She tells us what certain types of silicates have in common with phyllo dough, and explains how traces of ammonia on Ceres hint at unusual history for this dwarf planet.

Dr. Tiffany Meshkat describes direct imaging of exoplanets, which astronomers have used to discover enormous, young planets. She also talks about WFIRST, a mission under development that would be able to find and characterize exoplanets.

Dr. Armando Azua-Bustos talks about how he discovered the driest place on Earth— a region in the Atacama Desert not far from where he grew up. He explains how he collects and studies microbial life that live in these extremely dry regions.

Dr. Michele Koppes stops by to talk about her glacier research on planet Earth. She describes how a melting glacier triggered a staggeringly large landslide in 2015, and how glaciers can match even humans in their ability to transform the landscape.

Dr. David Ciardi talks about Vega, a bright star that’s “been a part of human lore forever.” Dr. Ciardi and his colleagues discovered that Vega has a nearby ring of dust, implying the presence of planets. He also describes an encounter with a giant inflatable bumblebee at Palomar Observatory.

A quick bonus episode about the April 8th, 2024 total solar eclipse in Mexico, the US, and Canada! I talk about the difference between a partial and total solar eclipse, and share some tips in case you want to travel to see it.

John Dailey explains how he uses his software engineering skills to discover asteroids at IPAC/Caltech. He helps solve problems inherent to working with astronomical data, such as the challenge of reading in and out huge volumes of data from hard drives.

Dr. Ingrid Daubar stops by to talk about HiRISE, a camera on a Mars-orbiting spacecraft that takes amazing images of the Martian surface. She explains how she uses these images to search for fresh craters, and how you (yes you!) suggest areas of the planet for this camera to image. (Correction to episode: Mars’ atmosphere is 0.6% that of  Earth, not 6%)

Marta Bryan shares her new results on exoplanets! She explains how she tested a theory of hot jupiter formation, and how she figured out that planet rotation rates are likely set early on in the planet’s lifetime.

Dr. Rahul Patel describes his search for undiscovered disks of dust around other stars. He explains how looking for fainter and fainter debris disks may bring us closer to discovering a planetary system similar to our own.

Dr. Ivy Curren talks about Mars’ moon Phobos, and how grooves on its surface indicate that the interior may be fractured. This small, mysterious moon is covered in faults, making it a dicey place for future missions to land.

Dr Roberta Paladini talks about the space-based Herschel Space Observatory, which was the largest infrared telescope ever launched. It looked at the sky in the far infrared, and discovered an abundance of water in star-forming regions.

Dr. Andy Thompson explains how he uses robotic ocean gliders to learn about our planet. He tells us how ocean water interacts with the atmosphere, and how parcels of water can preserve information about that interaction for thousands of years.

As part of the 2016 TED Fellows class, I got to meet cool people and I got to talk about asteroids. My TED talk is now online on www.TED.com (check it out!) and the companion book, “Asteroid Hunters”, by me, is now available in the US, UK, Canada, Australia, and India. There’s also e-book and audiobook versions. This bonus episode contains an excerpt from “Asteroid Hunters”.

Dr. Erin Burkett tells us what prairie dog research has to do with an earthquake early alarm system. She also talks about how to motivate people to prepare for earthquakes, and emphasizes the importance of storytelling in science communication.

Dr. Robert Hurt returns to the show to talk about artistic depictions of interstellar travel. We discuss the images of the seven-planet TRAPPIST-1 system he and Tim Pyle created— images that graced the cover of Nature and the front page of the New York Times. We also talk about Star Trek: The Next Generation, and what that TV show got right (and wrong) about the visuals of cruising through outer space.

Professor Raman Prinja talks about his new book, "Wonders of the Night Sky."  He tells us how we are lucky to live on a planet with a transparent atmosphere. He also shares stargazing tips for city dwellers as well as long-haul truck drivers.

The book is available at Simon and Schuster's website.

Note: I received a free copy of the book. 

Professor Mansi Kasliwal talks about the GROWTH project, which uses international teamwork to watch astronomical events around the clock. An individual observer is thwarted by sunrise, but together, an international team can continuously monitor supernovae, neutron stars, and asteroids over 24 hours.

Dr Linda Billings talks about the importance of clear communication across the expert/non-expert boundary. She describes the difference between the words “risk”, “hazard” and “threat,” as applied to near-Earth objects and gives advice to scientists who want to communicate their research accurately.

Dr. Marcia Burton stops by the show to talk about radio waves from Saturn, as measured by the Cassini Spacecraft. We listen to some audio clips, and she explains why it is so difficult to measure the length of Saturn’s day.