This picture shows Pluto (left) and its big moon Charon (right). This picture was taken by the Hubble Space Telescope in 1994.
Click on image for full size
Image courtesy Dr. R. Albrecht (ESA/ESO Space Telescope European Coordinating Facility) and NASA.

The Moons of Pluto

Pluto has moons. One of the moons is very big. The big moon is name Charon. The other two moons are small. They don't really have names yet. For now they are called S/2005 P1 and S/2005 P2.

James Christy discovered Charon in 1978. Charon is almost as big as Pluto! Some astronomers call Pluto and Charon a double planet.

S/2005 P1 and S/2005 P2 were discovered in 2005. A team of astronomers found the moons. The leaders of the team were Alan Stern and Harold Weaver. They were getting ready for the New Horizons space mission to Pluto. They were searching for new moons of Pluto. They were excited when they found two new moons! They used the Hubble Space Telescope to find the moons. S/2005 P1 and S/2005 P2 are much smaller than Charon.

S/2005 P1 and S/2005 P2 will get "real" names after a while. Astronomers want to be sure about the moons before they give them real names. The scientists will observe the moons some more before they give them names.

Nobody has seen any rings around Pluto so far. We don't think it has rings, but we don't know for sure.

Last modified January 23, 2006 by Randy Russell.

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