Pop History Moment: Pluto Was Discovered

On this day in 1930 Pluto was discovered by Clyde W. Tombaugh - based on calculations by Urbain Le Verrier, who first posited there was a planet beyond Uranus (in other words Neptune) and therefore trans-Neptunian objects... Tombaugh's astronomical enthusiasm would also lead to the discovery of numerous asteroids and extend to a fascination with UFOs.

Pluto and its largest moon Charon are sometimes treated as a binary system because the barycentre of their orbits does not lie within either body; no such conflict exists with the planetoid's other two moons, Nix and Hydra - which were discovered in 2005, just in time to witness Pluto being controversially stripped of its planetary status by the International Astronomical Union in 2006.
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