Pluto's Moons

As of summer 2012, astronomers had discovered five moons orbiting Pluto. The largest, Charon, discovered in 1978, is roughly half the diameter of Pluto itself. Of the other moons, two have been named by the International Astronomical Union -- Nix and Hydra. The other two, discovered in 2011 and 2012, have received the provisional designations P4 and P5, pending approval of formal names. Nix, Hydra, P4, and P5 are all quite small, with none larger than about 100 miles (160 km) in diameter, with the smallest only about 10 percent of that size.


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Featured Images

Global view of Charon, Pluto's largest moon
Red Roof Moon Friday, October 2, 2015
July 12 views of Charon and Pluto from New Horizons
Hours Away Monday, July 13, 2015
July 8 view of Charon, Pluto from New Horizons
Dynamic Duo Friday, July 10, 2015
Artist's concept of New Horizons passing by Pluto
First Encounter Thursday, July 9, 2015
New Horizons view of Pluto and Charon, July 1, 2015
Best Shot Tuesday, July 7, 2015
Three dwarf planets shown to scale with Earth and Moon
Dwarf Planets Monday, January 5, 2015

Radio Programs

Pluto’s Moons A small world with a big moon Wednesday, July 8, 2015


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