Is it true a tenth planet has been discovered?

Question

I don't believe it.

Answer 1

When Eris was discovered (initially dubbed 'Xena'), it was found to be bigger than Pluto, so the discoverers pointed out that it should be the tenth planet as it was bigger than the solar system's smallest planet.

However, many bodies not much smaller than Pluto or Eris had or were being discovered which could mean the number of planets in our solar system increasing with these smaller bodies.

So rules were drawn up to define a planet and unfortunately neither Eris or Pluto fitted the rules that define a planet. So we lost Pluto to the new 'dwarf planet' category.

The solar system now has eight planets.

Answer 2

http://en.wikipedia.org/wiki/Eris_%28dwarf_planet%29
http://en.wikipedia.org/wiki/Pluto

this seems to be a question about "136199 eris". "136199 eris" is about five percent bigger than "134340 pluto", but neither one is a planet.

they do orbit the sun, are ball-shaped, do not have an isolated orbits (a bunch of other similar bodies have similar orbits.), and are not satellites so they are not planets. this does not change anything about the solar system or pluto. it just corrects the mistake of classifying pluto as a planet initially. i don't know how long this will drag on tho. many planetary astronomers are not satisfied that the definition is rigorous enuf. i can accept that the definition is flawed, but i can not accept that pluto is a planet.

many astronomers consider pluto and charon to be a binary system, but two small bodies orbit that system. they are called nix and hydra.

i have been waiting for this since i was about twelve. i feel somewhat satisfied. i knew 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. this was the right thing to do, believe me.

incidental, "134340 pluto" was never a moon of neptune. neptune did capture triton. this is why triton has a retrograde orbit.

Answer 3

Actually, we lost a planet! There are at least three large bodies orbiting the sun beyond the range of Pluto, but after the discoveries of these the astronomical community decided to re-classify Pluto (and these three) as a different class of cosmic body- not so much based on size as on orbital plane. So, we discovered 3 but lost 4!

Answer 4

Not any more. Since the new definition of planet, we have only 8 known planets. I believe there are now 4 known dwarf planets.

Answer 5

Actually Pluto has been kicked off the list of planets and there are three further "planets" which may be given the official title of being planets

Answer 6

I heard it was true. A planet named Xena, like that stupid T.V series from New Zealand. Anyway, technically speaking, it's only the ninth planet again, since Pluto was down graded to a lump of rock.

Answer 7

The previous answer is incorrect. Xena is another of the rocks in the Kuiper Belt, like Pluto. It is not considered a planet.

We just lost the former 9th planet, so the answer to your question is obviously, "no."

Answer 8

Yes, they ruled Pluto as an asteroid or something, but they found 2 other planets Xena or something like that and something close to that only w/ a P

Answer 9

well zena was supposed to be the 10th planet but after the new defination of planet(pluto was removed from the major planets) even zena is no more a planet its a dwarf planet

Answer 10

your right! it is the 9thplant