Pluto, characteristic of the second dwarf planet of our Solar System

P L U T O

Characteristics

Pluto is a dwarf planet, according to the new classification approved by the IAU in August of 2006. and therefore 2º dwarfed planet of our Solar System. It was discovered the 18 of February of 1930 by American astronomer Clyde William Tombaugh (1906-1997) from the Lowell Observatory in Flagstaff, Arizona. It was the smallest planet and it has an eccentric orbit and highly inclined with respect to the ecliptic, that it crosses approaching in his perihelion until the interior of the orbit of Neptune. To this type of celestial objects they have been classified like dwarfed and plutonianos planets since they are in the Belt of Kepler.

It has three moons, of which the greater one is Charon with a diameter of 1/3 of Pluto and becoming also, in dwarfed planet, since the center of gravity between the Pluto-Charon system is outside the Pluto surface; being the other two Nix and Hidra; until the moment it has not been visited by any space probe, although one hopes that the mission New Horizons of the NASA flies over it in 2015.

Had fundamentally to its size and its unusual orbit, at the present time a fort exists debates in the astronomical community on if Pluto would have to continue being classified like a planet. Finally, the IAU adopted to Pluto like dwarfed planet, degrading it of dwarfed planet to planet in August of 2006 and to its Charon moon like 3º dwarfed planet of the Solar System, forming binary dwarfed planet system a unique in our Solar System.

Its great range to the Sun and the Earth, together with so large reduced his, prevents that it shines below magnitude 13.8 at his better moment (orbital perihelion and opposition), thus only can be estimated with telescopes from 200 mm of opening, photographically or with camera CCD: at his better moments it even appears like precise star of stellar aspect, yellowish, without distinguishing characteristics (diameter pretends inferior to 0.1 second of arc).

Pluto

2º dwarf planet of the Solar System

The Pluto orbit is also most inclined with respect to the plane in that they orbit planets of the Solar System, 17º, characteristic very common in the classified celestial bodies like dwarfed and plutonianos planets.

Pluto arrived for the last time at its perihelion in September of 1989, and continued moving by the interior of the orbit of Neptune until March of 1999. At the moment one moves away of the Sun, and it will not return to be to smaller distance than Neptune until September of 2226.

Outer satellites: Hydra and Nix

The 31 of October of 2005 the Space Telescope Hubble announced the possible discovery of two additional satellites of so large minor. These moons were observed in May of 2005 and confirmed its existence in June of 2006 they have received the names of Nix (provisional name S/2005 P 1)) and Hidra (provisional name S/2005 P 2). The name of both volume having them in account to two, since their initials NH render New tribute to the space probe Horizontes(NH), that took off in 2006 to Pluto. The preliminary observations are consistent with both bodies orbiting in the same plane that Charon and to distances two and three superior times. Both pretend to have between 100 and 150 km of diameter.

The dwarf planets Pluto and Charon and their satellites Nix and Hidra.

In the page Web you can obtain more data of each one of our planets and the dwarf planets defined by the IAU of our Solar System.