Pluto may lose its "planetary" status

The big debate has come up because Voyager spotted a big rock that was larger than Pluto. There are also seven moons that are larger than Pluto--Ganamyde, Titan, Callisto, our moon, Io, Europa, and Triton--and those first two are even bigger than Mercury.

Asteroids were originaly thought to be planets as well. After the first four were found, astronomers thought of them as planets because there was no way to find out how big they were. The fifth asteroid to be discovered was just a year before Neptune was, and then more and more asteroids were being found.

Originally Posted by Cellius

I've always wondered about our right to name something that's out of our solar system a name that's of Earth origin. I mean, how geocentric is that??? I'm sure there's a civilization out there that's far more entitled to name it something of their own design than us.

Well, then in that case, lets ask the dogs what they prefer to call their species. I'm sure that dolphins would also object to our bastardization of whatever they call themselves. It's not like we can just give the fine people who live on a planet orbing Alpha Centauri A a call and ask what they want things to be renamed as.

Jam it back in, in the dark.

They're going to have to change it eight or 12, no matter what. This proposal is going to have a drastic effect on our understanding and will outdate textbooks. Get ready for the change, because the IAU is going to come to a decision whether you all like it or not.

Hell, ever browse through the astronomy books at an elementary school? There are kids reading things that were printed before the first landing on the moon.

There's nowhere I can't reach.

Originally Posted by takeru

All my school lessons to the rubbish. Maybe one day we discover the Sun isn't really a star.

Oh fucking get over it. Science textbooks and information for other studies gets updated all the time. Just because the number of the planets is going to change when more than likely (blatant, asshattish assumption, yes) only would ever care about if asked in a quiz or game show, doesn't make your whole world crumble to pieces.

This thing is sticky, and I don't like it. I don't appreciate it.

Originally Posted by Acro-nym

Does Pluto have an atmosphere? I mean, given that they'd established Charon is a satellite, I can see why it couldn't be a planet. Part of the definition of a planet, if I remember correctly, is that it has to have atmosphere. Thus, these asteroids and moons that people may have wanted to become planets due to their size just don't fit the criteria.

That's one of the reasons why New Horizons was launched to Pluto. Pluto is believe to have a temporary atmosphere. Once it's reached out far enough, it sublimes onto the surface because of the sheer cold at such distances. By getting nearer to the sun, such as when it has crossed Neptune's orbit, it's enough heat to sublime back into a gas. New Horizons is supposed to investigate it right around when this freeze happens.

Originally Posted by guyinrubbersuit

Mercury doesn't have an atmosphere and it's still a planet.

Oh yes it does. A very thin one that is made up of the particles blasted off the surface from impacts and solar wind. The heat allows for the thin veil to escape the planet very easily. Go check it out at Nine Planets.

I am a dolphin, do you want me on your body?