Why is Pluto considered as asteroids?

Answer 1

The planets closest to the Sun: Mercury, Venus Earth and Mars are composed of rock. The planets beyond the asteroid belt Jupiter, Saturn, Uranus and Neptune are made up of gases. Pluto is composed of rock and ice.

Also, it has an elliptical orbit and at times crosses Neptune's path. There are periods of up to 20 years where it was the 8th body orbiting the Sun and Neptune 9th. (That is, if you do not count Ceres which is located in the asteroid belt) This leads scientists to believe it is an asteroid and part of the Kuiper belt.

Answer 2

because, unlike planets, Pluto's orbit is oval and it is comprised of ice, not dirt and rock. 3 other "planets" like Pluto have been discovered in the outreach of the solar system and they are not called planets.

Answer 3

The definition of what a "planet" is was up to interpretation at the time.

As of August 24th, 2006, the IAU (International Astronomical Union) redefined it, and as a result put Pluto in the new category of "Dwarf Planets", together with Ceres and Eris (formerly Xena), which are similar enough to deserve identical status, which would've put us up to 12 planets, instead of down to 8.

The difference between a dwarf planet and a planet being that a dwarf planet has not cleared the area of its orbital path, and a planet has.

The mere fact that this decision was necessary proves that the scientific community is at odds about whether or not these 3 dwarf planets are to be considered planets or not.

In effect, it all points to the answer that the only reason these scientists want Pluto to be a planet, is because it always has been. They don't want that to change.

So in short... Conservatism?

((Above conclusion possibly improvable.))

Answer 4

Pluto is not considered an asteroid, it is considered a dwarf planet. Dwarf planets are generally larger than asteroids, although the largest asteroid, Ceres, also qualifies as a dwarf planet.

The category of dwarf planet was introduced because it turns out that there are a number of relatively small objects in the outer system, of which Pluto is not the largest, and it seemed inappropriate to award the status of planet to all of them, and equally well, inconsistent to award the status of planet only to Pluto of that group of objects.

Answer 5

People who still consider Pluto a planet disagree with the IAU's new definition of Planet. However, it's interesting to note that most of these same people do not accept the other dwarf planets (Ceres, Haumea, Makemake, and Eris) as planets, even though most of them are larger than Pluto.

Answer 6

Pluto is no longer a planet because it's moon is bigger than itself. It's consider a dwarf planet. Therefore only 8 planets are left in the solar system.

Answer 7

Virtually all astronomers don't consider Pluto a planet, because Pluto is not a planet. It hasn't cleared its neighborhood.