Why is Pluto not a planet anymore? There was a controversy regarding this question. Pluto is a dwarf planet which belongs to the Kuiper belt. In the same time, Pluto is the largest body in this belt. It is consisted of ice and rock. But comparing to other Solar System planets, Pluto is rather small and you can not see it without a telescope.
Pluto was discovered in 1930. From that time, it was thought to be a planet of the Solar System. It was an official attitude until 2006. During the 1970s, a small planet was discovered within the Solar System. This was Chiron. Considering Pluto’s mass which is very low, its status as a planet was brought into question. Some time after, other objects were discovered; those were quite similar to Pluto. One of them was Eris which was considerably larger than Pluto. In 2006, the IAU (the International Astronomical Union) gave the definition of “planet”. Pluto didn’t fulfill the requirements of this definition, so it officially stopped being a planet. It was put into a new class of dwarf planets, along with others similar celestial bodies. There are still scientists who claim that Pluto should be in class of planets.
Pluto’s largest moon is Charon (discovered in 1978 by J. Christy). Nix and Hydra are two of the Pluto’s small moons that were found in 2005. These moons are incredibly close to Pluto. The name “Pluto” came from Roman mythology and it is the name of the god of death.
Pluto is very far from Earth, so there are not many facts known about how it really looks. It is known that the Pluto is probably covered in ice and methane and has low density. The temperature on Pluto is probably around – 230 ° C. Since the temperature is so low, it is highly unlikely that there can be any form of life on Pluto.