Which US astronomer discovered Pluto in 1930?
Correct answer: Clyde Tombaugh
Susan
Though Pluto was reclassified as a dwarf planet because "it hasn't clean its orbit", it is an extraordinary celestial body. First thought as a planet with five moons, Pluto and Charon seem to form a double planetary system orbited by four moons: Styx, Nix, Kerberos and Hydra, in an erratic ~ 284.5 years orbit around the Sun.
Chris
I can't imagine many people got this wrong