PLUTO AND BEYOND
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Pluto lies at the edge of the Solar System and is the smallest Planet. It’s 2300 km in diameter and is 5916 km from the Sun.
Pluto’s landscape is a patchwork of light, frost-covered regions and dark, frost-free regions. Made up of frozen nitrogen and methane, the frost covering is chilled to -238
° C. The frost-free areas are a few degrees warmer. This difference in temperature whips up cold winds in the thin nitrogen-methane.Astronomers once believed that a 10th Planet orbited beyond Pluto. New calculations show that this Planet probably doesn’t exist. But thousands of small ice comets do orbit beyond Pluto, in an area named the Kuiper Belt. Instead of being the Solar System’s smallest Planet, Pluto might belong to the Kuiper Belt and be the largest object in it.
All the other Planets in the Solar System orbit the Sun in the same flat plane, but tiny Pluto’s orbit is tilted into a long oval shape. Pluto has a 248-year orbit, and for most of it is the outermost Planet, but sometimes it crosses over the orbit of Neptune, making Neptune the furthest Planet from the Sun.
Wow! That’s Incredible!