What is Pluto?

Question

I know Pluto isn't a planet,but what is it?

Answer 1

It is no longer a regular planet, but rather a dwarf planet. They changed it in 2006. Here is the defintion of a dwarf planet:

1) is in orbit around the Sun
2) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (near-spherical) shape
3) has not cleared the neighbourhood around its orbit
4) is not a satellite

Because Pluto has not cleared the neighborhood around it (it's part of the Kuiper Belt, and has many neighbors), it can't be considered a planet.

It's not even the largest dwarf planet in the solar system. That honor belongs to Eris, which is also in the Kuiper Belt.

Answer 2

Although the International Astronomical Union (IUA) has now classified Pluto as a dwarf planet, many scientists still consider Pluto a classical planet (like Earth, Mars, etc.) and refuse to acknowledge the IAU's ruling and subsequent demotion of Pluto. Also, this relatively recent ruling may also be overturned by the IUA and is by no means a definite thing yet. Basically, if you follow the IUA then Pluto is a dwarf planet (for now), but if you follow the many dissenting scientists then Pluto is still a classical planet.

Answer 3

Its an dwarf planet, they only changed it from a planet to a dwarf planet because of how small it is. If Pluto was believed to be the size of Earth or Mars, or even our moon they never would have stripped it of its title.

If a Large earth (or Mars) sized object is found in the Kuiper belt, will they still be able to call it a dwarf planet? Or even, if they find one lager then the earth?

Planet - This 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 nearly round shape (due to a hydrostatic equilibrium)
(c) has cleared the neighborhood around its orbit. As now defined, the Solar System has eight planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.

Dwarf Planet - This 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 nearly round shape (due to a hydrostatic equilibrium)
(c) has not cleared the neighborhood around its orbit
(d) is not a satellite of another planet.

As defined, the Solar System has probably has at least one dwarf planet in the Main Asteroid Belt (Ceres), Edgeworth-Kuiper Belt (Pluto and Eris); and Oort Cloud (possibly Sedna). In addition, the "dwarf planet" Pluto is recognized as a prototype of a new class of trans-Neptunian objects.

Smaller Solar System Bodies - This category collectively refers to all other celestial bodies orbiting our Sun, Sol (including asteroids, comets, and satellites).

The size is a clear issue, because Neptune fails on C as well. Neptune and Pluto cross paths, never close enough to touch, but they still cross, if Pluto was larger, Mars size or even the size of our moon, they'll have a tuff time stripping it of its title.

Pluto has more moons then any rocky planet and has an atmosphere, and weather on it. It has just as much right to be a planet as any of the others. Comets still pass close to Earth even tho its rare. They're comparing its size and orbit to Earth and since its so much smaller amd its orbit is different, they have been trying almost since it was found to say its not a planet.

To me, its still a planet and I hope the New Horizons mission can get Pluto its planet status back!

Answer 4

Pluto is a dwarf planet, like Ceres and Eris. It was the ninth planet until August of 2006 when it was considered a dwarf planet. Pluto is part of the Kuiper Belt with Eris.

Answer 5

Pluto in Scorpio solar sq. Pluto Moon sq. Pluto Venus Trine Pluto Saturn Semi-sq. Pluto Uranus Semi-sq. Pluto Neptune Sextile Pluto - maximum persons have it Pluto Bi-Quintile Ascendant

Answer 6

It has been coined a "dwarf planet." Pluto is made of ice and rock and is extremely smaller then the other planets, there have also been a hundred or so objects just like it that have been discovered in the back of our solar system. Do we call each one a planet? No, it would be ridiculous, like calling every asteroid in the asterooid belt a planet because they all revolve around the sun. Therefore, scientists came up with the term dwarf planet to refer to all of these icy small objects.

Answer 7

In 2006, Pluto was classified by the International Astronomical Union as a dwarf planet (along with Ceres and Eris).

By definition, it has not cleared it's orbital neighborhood like planets have done. It shares it's orbital neighborhood with other Kupier Belt objects (such as the plutinos).

Answer 8

It's been termed a "dwarf planet." It's really a very large object from the Kuiper belt, a region of space beyond Neptune that probably holds another 20 to 50 Pluto-size objects or larger. (That's the reason it was knocked out of planet status - either learn anothre 20 to 50 NEW planet names, or just remove Pluto from that status.)

Pluto's make-up is probably a lot like a comet - water & CO2 ice, and rock.

Answer 9

It's new classification is "dwarf planet," and larget member of the Kuiper Belt. The characteristics that earned it the downgrade from planet to dwarf planet are:
* is in orbit around the Sun
* has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (near-spherical) shape
* has not cleared the neighbourhood around its orbit
* is not a satellite

Answer 10

Pluto is a lump of rock like Mercury, Venus, Earth, Mars, the asteroids, and other Kuiper objects. It doesn't care what we call it. It's just the definitions we use have changed.