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One Astronomer's Quest To Reinstate Pluto As a Planet
sarahnaomi writes: Most of us grew up believing that tiny, distant Pluto was the outermost planet in our solar system. Then, one day, the scientific powers that be decreed that it wasn't. But it seems the matter is far from settled. David Weintraub—who describes Pluto's exile as a stunt organized by a "very small clique of Pluto-haters"—would have the dwarf world rejoin the ranks of our Solar System's fully-fledged planets today. But solid evidence that Pluto deserves the title may come in July, when NASA's New Horizons spacecraft slingshots around the icy rock and sends us back a detailed picture of its composition. Pluto's planethood was revoked by majority vote on the final day of the 2006 IAU conference. Over 2,500 astronomers attended the meeting throughout the week, but only 394 votes ultimately decided Pluto's fate: 237 in favor of demoting the planet and 157 against.
That's the general idea. You have to add all the objects that meet the criteria. The current criteria does not depend on characteristics of the object itself; the definition includes characteristics of the surrounding objects as well. I tend to agree with the argument that the current definition is wrong, for this reason.
The Kuiper belt and scattered disk are where all the remaining stuff left over from the formation of the solar system ended up. It was pushed out there by the larger planets. Unless the body is very large, for example like Uranus, it's not going to be able to "clear it's orbit" in that region of the solar system. If another large planet did exist out there, it would probably scatter everything in it's orbit, effectively pushing the Kuiper belt and scattered disk further out. Any smaller body, perhaps even an Earth sized body, would be unable to clear it's orbit. So, if the Earth's double was found out there, you would have to call it a "dwarf planet" by the current definition. That doesn't make sense.
Really, the only categorization issue that I'm adamant about is that Pluto-Charon is called a binary. The Pluto-Charon barycentre is not inside Pluto, therefore Charon is not rotating around Pluto, the two are corotating around a common point of space between them. That's a binary.
The barycenter of the Sun-Jupiter system lies at 1.068 solar radii, outside the Sun. Do you think they should be called a binary?
Do what thou wilt shall be the whole of the Law
Jupiter emits more heat into space than it receives from the Sun.
(I agree with you, just playing devil's advocate).
Do what thou wilt shall be the whole of the Law