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Encyclopedia > Pluto I

(134340) PLUTO

Credit : HST/STSCI
Pluto seen by Hubble Space Telescope HST

Credit : John Hopkins University/NASA
Pluton vu par la sonde New Horizons

Origin of the name : click here.

It was long believed that Pluto was the last planet in the solar system. Pluto has a satellite, Charon. Making it a dual system -much like the Earth and the Moon- whose orbit around the Sun is tilted. The Pluto system does not belong to the same family as the other planets. It belongs to the special asteroid family, far away from the Sun: the objects of the Kuiper belt.  

Pluto is difficult to observe from the Earth's surface because of its low brightness, its appearance similar to a star and its very slow motion. The first spacecraft designed for observing Pluto is New Horizons. From Pluto, the Sun is seen as a very bright star (magnitude -19). In 2006 , Pluto lost its planet status and received a number as all the asteroids : 134340