Dr. Kirby Runyon shares his definition of "planet"-- a round celestial body that was never a star. Using this definition, there are over 150 planets orbiting our sun. He explains why the word planet matters, and why little planets might be the most common planets in our universe.

200: Pluto is a planet, and so is its moon with Dr. Runyon

Hear stories about the alien moons orbiting our Sun, of cold stars, and the future of space exploration.  Every week, scientist Dr. Carrie Nugent chats about an amazing part of our universe with an expert guest. Spacepod is the podcast that gives you an inside look into space exploration. Learn more: http://listentospacepod.com

Science

Astronomy

Earth Sciences

Dr. Jon Merrison talks about the Mars Simulation Laboratory. Here, scientists study what happens in low temperature, low pressure, windy environments.  He says visiting scientists often "come to our lab with some idea based on the conventional model and go away with data which makes no sense to them."

219: Breaking the models with Dr. Merrison

Dr. Morgan Cable returns to the show after nine years!  She tells us how she creates new minerals in her laboratory. She explains how this work helps shape NASA's Dragonfly mission. She encourages listeners to have confidence in their results.

218: Anything we try is new with Dr. Cable

Dr. Geronimo Villanueva tells us about solar system discoveries with JWST. He talks about several projects, including observing water plumes from Saturn's moon Europa and looking for rings around Mars. He shares what it feels like to use this incredible space telescope. 

217: A beautiful experience with Dr. Villanueva

I was sick for a few weeks this month and had to delay the scheduled interview. In the meantime, I've got a bonus episode for you. In this episode I talk about FindPOTATOs, which is software written by Nicole Tan and me, Carrie Nugent, to find asteroids and comets. I share some challenges we faced and how we overcame them. We hope that findPOTATOs can help astronomers find more asteroids, comets, and trans-Neptunian objects in their images of the sky!

Bonus: Carrie's research update

Professor Bill McKinnon, 2023 recipient of the Kuiper Prize, reflects on his career as a planetary scientist. He tells us about a theory of his that was proven right, one that was proven wrong, and what he thinks might be proven wrong in the future.

200: Pluto is a planet, and so is its moon with Dr. Runyon

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