Why is Pluto is not considered now a planet?

Answer 1

The current definition of planet now requires that the planet have an orbit clear of asteroids. Pluto doesn't have enough gravity to clear it's orbital area, and so is not considered a planet.

Answer 2

According to a new definition of the term "planet" voted by scientists today, Pluto is no longer a planet. A real planet is an object that is big enough to become round because of its own gravity and can orbit around the sun. A planet also has to dominate the neighbourhood around its orbit. Pluto has been thrown out of the planet group because it doesn't dominate its neighbourhood. Pluto's large moon, Charon, is about half the size of Pluto while all the true planets are far larger than their moons.

Answer 3

Pluto is much smaller - and has much less mass - than was believed originally. Really, the decision to demote it as a planet was long overdue.

However, the IAU uses a different definition for a planet; a planet is one that has "cleared its neighbouring region of planetesimals". This is somewhat related to mass, since a planetoid of very small mass will not have much influence on its surroundings.

Answer 4

Pluto is not considered a planet because it does not meet the criteria set by the International Astronomical Union for a celestial body to be classified as a planet. One of the key criteria is that the body must have cleared its orbit of debris, which Pluto has not done. Therefore, it is now classified as a dwarf planet.

Answer 5

Many reasons, including it's orbit, size, and other factors.