It’s not easy being a planet. For one thing, unless you’re Earth, it’s pretty lonely out there in the solar system. Sure, Mars is getting all the attention these days with some incredibly impressive visitors. But as red-hot as Mercury is, there’s not much going on. Saturn’s got rings, but no medals or awards. And Pluto? Poor Pluto. Discovered on February 18, 1930, Pluto’s very planetary existence was in a sort of limbo until 2006. That’s when it got the boot.
To be a planet, the International Astronomical Union says an object has to
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orbit around the Sun
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have sufficient mass to assume hydrostatic equilibrium (be a nearly round shape)
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have “cleared the neighbourhood” around its orbit
Poor Pluto hasn’t managed to clear all the other junk out of its odd orbit.
Today would be a good day to have a Pluto scavenger hunt. If your students have access to computers to do research, have them scour the Internet to find out something interesting about Pluto. A trip to the library would work too. Better yet, have them write a short speech written from Pluto’s point of view in which the dwarf planet reacts to being “demoted.” Stop by TheMailbox.com for additional FREE ideas for studying the planets.
OH my — when I first saw this in my inbox I thought Pluto the dog!!!!! Sorry – Just getting around to opening this!!! It makes it difficult as teachers to teach kids when the scientist keep changing everything on us!!!! I bet in a few years poor Pluto will be considered a planet. And all the little songs and things to help kids remember the planets — what happens to those? Well it could also be used as a good way to show kids about bullying — how would they feel if they were not longer part of the planetary system? Yes — I have had one too many snow days!!!!!