The International Astronomical Union named Pluto's fourth and fifth moons Kerberos and Styx.
Two newly discovered moons orbiting Pluto were named Nix and Hydra.
The Hubble Space Telescope captured the first images of the surface of Pluto.
United States Naval Observatory astronomer James Christy discovered Pluto's largest moon.
Pluto was officially named.
Clyde Tombaugh announced the discovery of Pluto.
American astronomer Clyde Tombaugh discovered Pluto.