Pluto: The Ice Planet

Guess what? Pluto has more in common with Triton, Neptune's largest moon, than it does with any of the other eight planets in our solar system. Pluto is actually smaller than Triton.

Pluto is tilted 122.5 degrees on its axis. It has an extreme elliptical orbit. Because of the shape of Pluto's orbit, it actually slips inside of Neptune's orbit once every 248 Earth years for a period of twenty years. Pluto has one natural satellite, Charon, which is half the size of Pluto. Because Pluto and Charon are comparable in size, many scientists consider them to be a double planet (but many scientists don't consider Pluto a planet at all!). Studies conducted using a spectroscope have detected methane frost on Pluto and water frost on Charon. Like Triton, Neptune's satellite, Pluto has an atmosphere of nitrogen and methane. Pluto's atmosphere appears to extend out to include Charon, which suggests that they may share an atmosphere. Through the Hubble Space Telescope, Charon appears to be more blue in color than Pluto. During the time in its orbit when Pluto is farthest from the Sun, its atmosphere condenses and falls to the surface as frost.

Pluto

A Question Why is Pluto considered part of a double planet system?

The Facts

Did you know?

The Answer

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