Best Of Blue Dot: What Is A Planet?

May 22, 2020

Credit NASA

In this episode, inspired by our good friend Alan Stern, the Principal Investigator for the New Horizons Spacecraft, we examine a question that has vexed astronomers, planetary scientists and 5th graders, for decades: "What exactly is a Planet?" And more importantly, why should we care about definitions like this in science.

Dave is joined by a team of planetary scientists who study, guess what, planets, as their primary mission in life. Jim Bell, Kirby Runyon, David Grinspoon, and Phil Metzger join Dave to talk about how we've looked at this topic in the past, present and moving forward into the future as we discover more and more bodies in and out of our solar system that, if seen on the viewscreen of the Starship Enterprise would certainly look like planets. 

While there is a debate between factions who are astronomers and those who are planetary scientists, no matter where you fall, you'll find this episode, in the parlance of Mr. Spock, "Fascinating."