Why pluto not a planet anymore????

Question

um i heard somewhere that Pluto wasnt a planet anymore! why????

Answer 1

You're right it has been stripped of it's status, or "plutoed".

The top astronomers all gathered together to thrash this one out last year. As so many quasi planet objects are being discovered they had to decide whether they constituted planets or not, and as some were Pluto's size, would pluto be downgraded?

It was and is now a dwarf planet.

Answer 2

It's a matter of classification. When Pluto was discovered it was called a planet, even though its orbit was wildly eccentric compared the the eight main planets. In fact some astronomers considered it an escaped moon of Neptune rather than a planet in its own right. However, with only one weird planet, Pluto, it didn't really make a difference, and for the better part of a century, Pluto was called a planet. Well, in the past few years astronomers have discovered dozens of bodies just like Pluto, some even larger, orbiting in the far reaches of the Solar System, with probably hundreds still undiscovered. So there was a problem, were these all planets? Did we want a Solar System with hundreds of planets, all but eight of them frozen lumps orbiting in the far reaches of the Solar System? So scientists decided to redefine the word planet in such a way as to differentiate the main planets from all the rest, and so the category dwarf planet was created. So basically all astronomers did was correct an old mistake, Pluto never should have been called a planet in the first place. This isn't the first time this has happened, the asteroid Ceres and three other asteroids were classified as planets for about 50 years in the early nineteenth century, as were the moons of Saturn and Jupiter at an earlier point.

Answer 3

http://en.wikipedia.org/wiki/pluto

pluto does orbit the sun, is ball-shaped and is not a satellite, but it does not have an isolated orbit (a bunch of other similar bodies have similar orbits.) so it is not a planet, and it never was. this was the right thing to do, believe me. this does not change anything about pluto or the solar system. this just corrects the mistake of classifying pluto as a planet initially. pluto was discovered during a search for something that does not exist: a planet orbiting the sun beyond neptune. pluto just happened to be where he was searching for this hypothetical planet. astronomers soon realized that pluto was not massive enuff to what they were looking for.

i have been waiting for this since i was about ten when i learned that pluto didn't fit the pattern set by the major bodies in the solar system so it was an anomaly. it just felt "out of place". now that astronomers have found hundreds of other bodies with similar orbits, classifying "134340 pluto" as a planet is even more irrational. one of these, "136199 eris", is about five percent bigger than "134340 pluto".

i feel somewhat satisfied, but i don't know how long this will drag on tho. many planetary astronomers are not satisfied that the definition is rigorous enuff. i can accept that the definition is flawed, but i can not accept that "134340 pluto" is a planet.

this same thing happened has happened before. in 1800, an astronomer found a body orbiting the sun between the orbits of mars and jupiter and thought it was a planet. astronomers finally stopped classifying them as planets in about 1850 after they found several other bodies with similar orbits, and no one thinks ceres, pallas, juno, and vesta are planets today.

incidentally, "134340 pluto" was never a moon of neptune. neptune did capture triton. this is why triton has a retrograde orbit. many astronomers consider pluto and charon to be a binary system, but two small bodies orbit that system. they are called nix and hydra.

Answer 4

Why is Pluto not a planet? Because it has been found to be smaller than once thought, and if we were to consider Pluto a planet, a number of asteroid in the asteroid belt would have to be considered planets too.

Also, Charon, Pluto's 'moon' is almost 1/2 the size of the planetoids, proportionately, it is the largest moon in the solar system, so, for awhile, Pluto and Charon were considers 'double-planets'

The universe is amazing, is it not? What we haven't discovered... TO MARS!

Answer 5

Ultimately, Pluto does has enough clout to make as a top flight planet. It is still a planet, albeit a dwarf one. It also has some peculiarities about it's orbit; as explained here http://wp.me/p6SLjN-bM

Answer 6

pluto is not a planet anymore because astronomers found another planet/asteroid after pluto which is bigger than pluto. Pluto is now something known as a Dwarf planet.

Answer 7

It IS a planet. Neptune passes into pluto's orbit just as much. NASA didn't listen to the stupid IAU demotion of Pluto, so why should we.

Answer 8

I say we all rally around Pluto! This is BS! Write your Congressman/woman! Size doesnt matter! Nor does Orbit...

Answer 9

Because astronomers are mean and want everyone to have to kind of re learn the solar system!! I think it should be a planet!

Answer 10

because it does not have it's own orbit, it overlaps with uranus's orbit for about 20 years.... but planet or not, it's still pluto