why is pluto a dwarf planet?

Question

??just wondering??

Answer 1

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

on 24 august 2006, the international astronomical union voted to reclassify pluto as a "dwarf planet", but 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.

pluto does orbit the sun, is ball-shaped, does not have an isolated orbit (a bunch of other similar bodies have similar orbits.), and is not a satellite so it is not a planet. this does not change anything about the solar system or pluto. it just corrects the mistake of classifying pluto as a planet initially.

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.

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

Answer 2

Pluto is a dwarf planet because it was smaller that the other planets and was believed to orbit another something.

Answer 3

The International Astronomical Union decided that Pluto was no longer a planet. Instead, they decided to classify it as a "dwarf planet".

See the details below.

RESOLUTION 5A
The IAU therefore resolves that "planets" and other bodies in our Solar System, except satellites, be defined into three distinct categories in the following way:

(1) A "planet" [footnote 1] is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighbourhood around its orbit.

(2) A "dwarf planet" is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape [footnote 2] , (c) has not cleared the neighbourhood around its orbit, and (d) is not a satellite.

(3) All other objects [footnote 3] except satellites orbiting the Sun shall be referred to collectively as "Small Solar-System Bodies".


Footnote 1: The eight "planets" are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.

Footnote 2: An IAU process will be established to assign borderline objects into either dwarf planet and other categories.

Footnote 3: These currently include most of the Solar System asteroids, most Trans-Neptunian Objects (TNOs), comets, and other small bodies.

RESOLUTION 6A
The IAU further resolves:

Pluto is a "dwarf planet" by the above definition and is recognized as the prototype of a new category of trans-Neptunian objects.

Answer 4

I think Pluto is a dwarf not a planet at all.

Answer 5

pluto and its moon charon are out in a area of the picture voltaic equipment referred to as the kuiper belt, it really is the position alot of comets come from. its orbit is tilted from the plane the position something of the planets orbit, its made from ice and rock while the different outer planets are gas giants, so it type of feels type of out of position fore a planet. plus there have been different discoveries out previous pluto of different dwarf planets and a pair of them are larger than pluto so we would ought to assert that there are 12 planets in our image voltaic equipment or shall we in basic terms classify those as dwarf planets and say that we've 8 important planets contained in the picture voltaic equipment. so thats why scientists have categorised those as dwarfs because they thik they are gonna locate alot more effective of those and they dont want to save including to the list of planets because quite quickly we would ought to assert something like, "there are 387 planets around the solar".....desire this helps!!!!!

Answer 6

Plutp is a dwarf planet because it is so small.

(good question)

Answer 7

because a bunch of PC idiots said so

the standards that it didn't meet are
1. Size - many moons are bigger
2. Orbit - it doesn't really have it's own it and it's moon revolve around a central point and the group have an orbit that crosses Neptune's ( all the other planets have a discrete almost circular orbit )

Answer 8

After four months, there's still one person who's totally clueless about this whole Pluto rubbish? Why can't you read the other 500,000,000,000,000,000 times this stupid question has been asked.

Answer 9

because it is a small planet. It got picked on.

Answer 10

they say it isn't a planet anymore