Foxglove Faerie
... "WHO GETS TO DECIDE THESE THINGS?!?!" and he said it was a whole conference of astronomers, scientists, etc. ...
Yes, Pluto's designation as planet has actually been under debate for some time, but since the astronomers have never actually defined "planet" before this last week, it had fallen under the 'planet' identification of a large spatial body in orbit. Now that an actual definition of "planet" has been discussed and decided upon (at the international astronomer's convention -or whatever they call it- last week), Pluto has been demoted to "Dwarf Planet". They decided that to be a planet, orbiting bodies in our solar system must have a nearly circular/regular orbit around the sun (among other criteria). Pluto's orbit is so elliptical that it actually crosses Neptune's orbit for several years of its orbit, making it (Pluto) closer to the sun than Neptune!
eek The new Planetoid / Dwarf Planet "2003 UB313" (nicknamed Xena) also falls in to the Dwarf Planet category, as does the largest asteroid in the solar system, Ceres... and possibly a moon or two! So instead of having 9 planets, we now have 8, plus at least 3 Dwarf Planets (plus several more to be absolutely identified), in our solar system!
gonk
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