Pluto's surface is composed mainly of various ices, although it has a few sections of rocky regolith. It is also thought that there are frozen hydrocarbons on the surface.
Pluto has a medium-sized atmosphere comprising of Methane, Nitrogen, and Carbon Monoxide. Pluto's orbit is eliptical, more so than the inner planets. When Pluto approaches its Aphelion, most of its atmosphere freezes and falls to the ground as snow.
Pluto has six known moons. In order of size they are: Proserpina, Cerberus, Hydra, Chimera, S/2011 P5, and S/2012 P6 . Pluto and Proserpina are sometimes called a double planet system due to their closeness in size, although it was proven that Proserpina orbits Pluto. It is highly likely that Proserpina was formed by a large protoplanetary object crashing into Pluto during planetary formation. Most of the other moons are likely space debris captured by Pluto's gravity.
Order of Pluto's Moons
- S/2011 P5
- S/2012 P6
Pluto was first visited by the Voyager I probe during its system flyby.
Pluto was then the target of the Tartarus (OTL Pluto Kuiper Express) Probe, which was launched in 2003. Set to arrive at Pluto in late 2012 or early 2013. The Tartarus mission is to gather a substantial amount of data about Pluto's characteristics and information about its moons.