I the planet Pluto not considered a planet anymore?

Question

Not sure where I heard that from. Can anyone answer this one?

Answer 1

If Pluto is accepted as a planet, then there are a host
of other bodies that would also need to be called planets
because they are similar to Pluto, but just weren't discovered
until more recently... so it was either demote Pluto or open
the door for dozens of new "planets".

Answer 2

Size isn't the answer. Nor is a non circular orbit. Mercury is just as non circular.

This actually happened once before. About 1800 they discovered a new planet, Ceres. Then, they started to discover many small objects with about the same orbit. Today we call them asteroids. After a while people realized that calling one particular asteroid a planet, even if it was the biggest one, made no sense. So Ceres was no longer considered a planet, just another asteroid.

Same thing with Pluto. They've started to discover a whole lot of things just like Pluto, in the same general region. They're called Kuiper Belt Objects, KBOs. As they discovered more, preople started saying Pluto should no longer be considered a planet. In 2005 they discovered a KBO which they think (it's not certain) is bigger than Pluto. Either that was the tenth planet (with a lot more to come) or Pluto should just be another KBO, although it was the first one discovered and is the brightest.

That made more sense. So, Pluto is no longer considered a planet, just as Ceres, which once was one, is no longer a planet.

More info about KBOs:

http://solarsystem.nasa.gov/planets/profile.cfm?Object=KBOs&Display=OverviewLong

Answer 3

Here is the thing:

1. Four small planets, then four big planets ... then comes one small planet "pluto".. hmm doesn't make sense.
2. All planets have handsome elliptical orbits, but pluto has a weird one .. hmm doesn't make sense.
3. Pluto has a moon, charon .. which is a little bit smaller than pluto, makes it a binary system not a planet - moon system .. hmm something fishy in here ..

So, because of the previous reasons, scientists of last week's meeting decided to down grade pluto to "dwarf planet" hence not a planet. hmm :( I used to love pluto ... goodbye pluto ..

Answer 4

Pluto is not considered a planet anymore because when the wrote the definition of what a planet is, Pluto didn't fit the definition.

Answer 5

no. because it didn't meet the new requirements for planets. because if they did keep pluto they would have 50 to 100 other planets so they had to make a diff. but pluto is classified as a dwarf planet.

Answer 6

It is now categorized as a "dwarf planet", along with a few other objects with similar characteristics.

They say a planet has to clear a path in its orbit and Pluto apparently has not done that.

Answer 7

It was reclassified as a dwarf planet a few days ago.

this is part of a long long debate about pluto, the main points being that it is small and its orbital path crosses over neptune's.

Personally, I find it insulting to call it a dwarf planet, it's just trying to be unique!

Answer 8

They've been going back and forth on that one. I don't know if it's official yet, but the latest word seems to be that Pluto is an asteroid, but the general public has yet to be informed. Just the same, it's still a planet to me.

Answer 9

Yes, it is no longer a planet, that is the recent report. That's what they've decided according to their definition of a planet.I think they call it now a dwarf planet which is different from a "planet." It has a lot of effects for saying it so as people have to edit or rewrite the textbooks and other books.

Answer 10

thats because the scintists of the planet earth know less than the scientists of the planet Pluto, so one more point to prove the jealous human nature.