This episode we mark the 90th anniversary of Pluto's discovery by exploring the life of US astronomer Clyde Tombaugh, take a look at the Pluto's rise and fall as the 9th Solar System planet and answer the question Why is Pluto not a planet?
Plus, we examine a recent International Astronomical Union campaign that saw 112 countries around the world name newly-discovered exoplanets.
If the above embed isn't working, you can find the podcast on Radio Astronomy's Acast or Spotify pages.