Why is the AIU considering Charon a planet?

Question

their new official definition of planet says that it must orbit the sun,but charon orbits Pluto!!!!

what about the new moons of pluto,nix and hydra?are they considered planets now too?

Answer 1

because both Pluto and Charon orbit around a barycenter outside Pluto
the barycenter has to be inside Pluto for Charon to be considered a moon
but since Charon has enough gravitational pull between it and Pluto for the barycenter to be outside of Pluto then both are considered a double planet

Answer 2

Well, we have known for some time that Charon technically does not orbit Pluto, and that they actually orbit each other, like a binary system. So, in the new official definition of a planet (why do they need 4 pages? 4???????), one condition is that the center of gravity must be within the object for it to be a planet.

Answer 3

Actually, Charon and Pluto both orbit a point in space near Pluto, so the IAU is considering declaring Pluto/Charon to be a binary planet.

Answer 4

Although Charon and Pluto circle each other, they mutually
orbit the sun as the center of gravity, not each other..
Seems kind of a technicality but there it is...
I would stick with the 9 planets as they are because we do
not have a "GOOD" reason to make any changes..

Answer 5

They are supposed to be debating for a week sarting today, as a matter of fact. The options are, 8 planets, 12 planets or 44 planets. There is no new definition YET. It's something they have been debating for years, I dont even know if a conclusion can be made. So, right now, there's only 9 planets.

Answer 6

IAU says a planet requirement is orbiting a star whiile it is not a star itself and have enough gravity to form a sphere.
Charon and Pluto's center of gravity is in between them in space, while like the our moon, which fills the requirement, could not be classified as a planet because the cente rof gravity of the moon is inside Earth.

Answer 7

Because of it's relative size compared to Pluto.They are almost the same size making this couple quite odd.Leading astronomers believe that near the beginning stages of the creation of our planets,Pluto was stuck by very large a large celestial body,that tore the planet in half.Over time the surfaces rounded out...tom science

Answer 8

Its because of its size. Some people consider it to be a twin planet, with both of them orbiting the sun together. I don't think its been decided if it will be considered a planet yet though.

Answer 9

9 or 10 or 12 or more it makes little difference to me if we get hit with an asteroid. What has Hubble found in the way of Asteroids or other potentially life threatening bodies? Interesting debate anyway. One of these days the text books will catch up maybe they should just have binders so we can replace the old data.Personally though I think we should stop using them anyway and save our resources for oxygen.