Brent Barbee returns to the show to talk about deflecting asteroids. He explains how an asteroid might react to an impact, and also talks about the proposed DART mission, which would change the orbit of a small asteroid moon.

Dr. Solange Ramirez returns to the show to talk about her new position as Project Manager of the Sloan Digital Sky Survey V. Amount other things, the project will study over six million stars and how black holes change over time. These millions of measurements will be made using a robotic telescope system that is currently being built.…

Rob Seaman of the Catalina Sky Survey talks about time, and why you need to know the time to discover asteroids and comets. He explains how he installed a highly accurate clock, and makes the case that "natural time" is better than "cold, heartless atomic time."

Dr. Dave Tholen talks about near-Earth asteroids. He explains why they can be difficult to observe, and how he manages to spot them anyway. He also tells the story of a particularly famous asteroid that he discovered, and sets the record straight about its name.

The James Webb Space Telescope hasn't launched yet, but scientists already have plans to use it. Dr. Kartaltepe talks about how she'll use it to study galaxies. She's interested in the first galaxies that ever formed, as well as galaxies at a wide range of distances from Earth.

Urey Prize winner Dr. Francesca DeMeo stops by the show to talk about her asteroid research. She explains what a differentiated asteroid is, and tells us about her asteroid classification system. She also shares a new result, and explains how it may change the way we think about solar system formation.…

Dr. Matthew Payne talks about his exoplanet research, which involves looking for periodic dimming in stars. We discuss the Kepler and TESS space telescopes, and he explains why he's so interested in measuring the masses of exoplanets.

Dr. Joanna Carey talks about her research on our home planet, Earth. She explains how the climate change we're experiencing is ten times faster than any in geologic history. We also discuss why small changes in carbon emissions today will make a huge difference to the future climate, and things everyday people can do to mitigate the damage.…

Dr. Alejandro Soto returns to the show to talk about how lakes on Titan and on Earth influence the nearby atmosphere. He talks about how lakes create breezes that allow for sailing on Earth, and how the situation changes on Titan.

Dr. Matt Holman, head of the Minor Planet Center in Cambridge, Massachusetts, stops by to talk asteroids. The Minor Planet Center handles about a hundred thousand asteroid observations a night, from observatories all around the world. He talks about the difficulties in linking asteroid observations, and the discovery of the first interstellar a ...…

Dr. Luisa Rebull returns to the show to describe new research with the Kepler space telescope. Her ingenious study takes advantage of Kepler's strengths, and has produced results that stump theorists. Dr. Rebull explains why this data has given her "a whole new appreciation for post office workers."

Dr. Sebastiano Padovan talks about the planet closest to the sun, Mercury. He compares the evolution of planets to movies, and says that understanding a planet's history from its current state is like trying to figure out the plot of an entire movie from a single snapshot. He also explains why Mercury is "a favorite" of scientists who do comput ...…

Tim Thompson, former JPL scientist and member of the Mt. Wilson Institute Board of Trustees, talks about the Mt. Wilson Observatory. He explains why he doesn't operate the Mt. Wilson telescopes himself, and tells us why astronomers hate the twinkling of the stars. This episode was recorded on location, and Tim talks about the many public events ...…

Dr. Ingrid Daubar returns to the show to tell us about the InSight mission to Mars. InSight carries a seismometer and a self-hammering heat probe, and will explore the interior of the planet. She tells us what it was like to be at InSight's launch, and explains how the mission's landing site was selected.…

Dr. Shohini Ghose talks about quantum entanglement, which she describes as an "amazing, weird handshake across space and time." She tells us about quantum information science, which finds useful applications for the weird quantum qualities of particles.

Dr. Burçin Mutlu-Pakdil talks about her amazing discovery-- a galaxy with both an inner and outer ring. The existence of such a galaxy had not been predicted before she discovered it, and there's no theory yet that can explain how such an unusual object was created.

Dr. Michele Koppes returns to the show to talk about her experiences studying glaciers in the field. She describes what a glacier sounds like at night, and why a good glaciologist is generally handy with a soldering iron.

Dr. Rosalie McGurk talks about her quest to find pairs of black holes. She explains how she used several different telescopes to solve this problem, narrowing the list of potential candidates from hundreds of thousands to about twenty.

Dr. Tom Connor stops by the show to talk about massive galaxy clusters and the CLASH project. We talk about naturally occurring gravitational "telescopes" that allow us to see even farther into space, and Dr. Connor makes some fun analogies to cupcakes and crime bosses.

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 e ...…

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.

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 p ...…

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”) ...…

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.

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.symphonyofsci ...…

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.

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.