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Showing posts from March, 2010

134340 Pluto, and his little brother Charon

Pluto, formally known as a Planet, has been recategorized by the International Astronomical Union on August 24, 2006 as a dwarf planet. Although no longer considered an upstanding member of the solar system (to borrow a phrase from 2 Skinnee J's), Pluto is now the largest member of the Kuiper belt. So it's not all bad for Pluto. Rather than being the smallest fish in a sea filled with giants like Jupiter, Pluto is now the largest member of a smaller sea.

But what about Charon. Charon is the largest of Pluto's moons, or rather that's what Charon used to be. Since Pluto is no longer a planet, it's inaccurate to call Charon a moon, a nickname for natural satellites such as the Earth's Moon that orbit planets.

At times Charon was even referred to as a double planet with Pluto because of its size compared to Pluto, just over half the size of Pluto. Indeed, Charon and Pluto are so close that neither actually rotates around the other. Instead they are deadloc…