Dr. Katherine Kretke investigates how planets are formed with computer models. Her new research had a surprising result— that pebbles play a key role in forming terrestrial planets like Earth and Mars.

Paulo Younse has spent over 5 years studying hermetic seals for tubes. But these aren't just any tubes— there the tubes that will travel to Mars and carry rocks back to Earth. He describes the challenges of designing the perfect tubes for this ambitious venture.

Dr. Heather Kaluna talks about space weathering, which changes the surfaces of the moon, asteroids, and Mercury. She studies space weathering in a laboratory, where she can reproduce hundreds of millions of years of weathering in just forty minutes.

The James Webb Space Telescope is the biggest astronomy project in the world right now. It's an amazingly complex robot, and some of its sensors need to be kept cool. Dr Kris Stone talks about the cooling system, and how it will be tested during the longest continuous test ever conducted at NASA's Jet Propulsion Laboratory.

Dr. Lauren White talks about designing and building instruments for the International Space Station (ISS). She shares a secret about designing instruments for the outside of the space station, and also talks about being the first American to command a laser on the ISS.

Dr Morgan Cable comes back on the podcast to tell us about how she and a team of scientists searched a fresh lava field in Iceland to look for signs of life. They pretended to see the landscape like a rover would, so that the lessons they learned in Icela

Dr. James "Gerbs" Bauer talks about comets, the icy dirtballs (or dirty iceballs) that orbit the Sun. We talk about the ancient Egyptian term for comets, why you probably shouldn't eat a comet, and an exciting new discovery made by the NEOWISE team.

The New Horizons mission revealed Pluto's jaw-dropping vistas and geophysical mysteries. One listener wanted to know why the spacecraft didn't go into orbit around Pluto. Tom Spilker, interplanetary travel expert, tells us the answer.

In part 2, engineers who worked on the Galileo probe discuss what it was like when the probe entered Jupiter's atmosphere. This episode includes a bonus story about Pioneer Venus.

Celebrating the 20th anniversary of the successful deployment of a probe into Jupiter's atmosphere, this episode is a series of interviews with the engineers who worked on this challenging, historic mission.