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Our next question is from Arun from California: Could this mission prove that Pluto isn't a planet?

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This seems to be the question on everyone's mind right now.  In fact, in today's Parade magazine --

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Really?

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-- on the cover.  That was the cover story.  You know, how many planets are there?  Hint, the answer is not nine.

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Because some people want to demote Pluto, because Pluto is very small.  It's only -- it's less -- it's only about 70

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percent the size of the Earth's moon, and so some people say, well, geeze, Pluto shouldn't be a moon for that reason.

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But on the other hand, Pluto is spherical, which means it has enough mass to form a sphere.  It has an atmosphere,

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has some other attributes that we normally associate with planets.  So a lot of people think that Pluto is legitimately a planet.

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It's been a planet for 70, 60 years and there is no way that we can take it off the list now.

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But the problem is, earlier this summer, a new object was discovered out in the Kuiper Belt as slightly larger than

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Pluto.  So if you're going to call Pluto a planet, you have to call this other object a planet.  It's been nicknamed, by the way, Xena.

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I don't think that's gonna stick, but... And, and the interesting thing is that we've only uncovered the tip of the iceberg.

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There are probably lots of Pluto-sized or Charon-sized objects out in the Kuiper Belt and we'll

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probably end up with on the order of 100 planets eventually.

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