Episode 93 of Stories from Space is now Live!
This week, I sat down with Dr. Will Grundy, an astronomer and planetary scientist with the Lowell Observatory — the place where Dr. Tombaugh discovered Pluto in 1930! Who better to speak to about Pluto and the “Great Planet Debate”? The debate began in the early 2000s with the discovery of many new objects orbiting beyond Pluto. It was “resolved” with the IAU decision of 2006 that defined a planet as a celestial body that:
“(a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and © has cleared the neighbourhood around its orbit.”
As you’ll see in this episode, the debate is far from over and can get pretty contentious. Planetary scientists, astrogeologists, and people from other disciplines have criticized the IAU’s rather narrow definition and believe that planethood should be extended to all the major bodies of our Solar System. Follow the links below to learn why…
Where to Listen:
Originally published at http://storiesbywilliams.com on February 21, 2025.
