Alas, Poor Pluto, No Longer One of Nine

Alas, poor Pluto is no longer considered to be a planet by the scientists of the IAU (International Astronomical Union). Astronomers use three criteria for a body to be called a planet: 1, it has to be in orbit around the Sun. 2, it has to have enough mass to pull together so that it becomes nearly round. And 3, it has to clear other bodies in space near its orbit. Pluto meets the first two tests, but it does not have enough mass to clear the space around its orbit. So Pluto has been renamed a Dwarf Planet. All you kids who have memorized the planets in order from the sun will now have to stop at Neptune, the eighth planet from the sun. Here’s some more information about Pluto from Space.com, a really neat site that you can use to find out all kinds of interesting facts about what’s out there.