what is pluto now considered?

Answer 1

http://en.wikipedia.org/wiki/Pluto
http://www.iau.org/fileadmin/content/pdfs/Resolution_GA26-5-6.pdf

on 24 august 2006, the international astronomical union reclassified 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. for the time being, the iau classifies it as a "dwarf planet".

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

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.

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

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

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

Answer 2

I was under the impression that Pluto was now considered to be a part of the Kuiper Belt of Asteroids. If memory serves Me correctly, didn't The International Astronomical Union (based in Paris) r-classify Pluto on August 24th of this years after several years of consultation with members of the Astronomical Community?

Answer 3

Pluto is now apart of the new class of planets called Dwarf Planets. There are several other objects including a larger one in this class. They are also called Trans Neptunian Objects as there orbits cross inside the orbit of Neptune. They are not from the same place as comets though... Comets come from the Kuiper belt and the Oort cloud of which both are much further away than Pluto.

Answer 4

The International Astronomical Union decided that Pluto was no longer a planet. The reason is that while Pluto is round, orbits the sun, and has three moons, it has not cleared (via gravity) its own orbit of debris. 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 5

Pluto is now considered a "dwarf planet" based on the re-definition of a "planet" by the International Astronomical Union.

Answer 6

A Dwarf Planet.

Now, instead of being the smallest, wimpiest planet in our solar system, it gets to be the second largest of the small fries!

Answer 7

A dwarf planet

Answer 8

A Walt Disney character.

Answer 9

It the Mother Ship of the aliens living on the dark side of the moon.

Answer 10

It is now classed as a Minor Planet (or sub planet)