Pluto

Pluto is the ninth and smallest planet of our solar system. It was discovered by the astronomer Clyde Tombaugh at the [Lowell Observatory]? in Arizona in 1930. Its highly eccentric orbit makes it the eighth-most distant planet from the Sun for part of each orbit. Pluto orbits in a 3/2 resonance? with Neptune. Because of its small size and eccentric orbit, there has been some debate over whether it truly should be classified as a planet. There is mounting evidence that Pluto may in fact be a member of the Kuiper Belt, only one of a large number of distant icy bodies. A subclass of such objects have been dubbed plutinos, after Pluto.

• Approximate Mass: 1.29×10²² kilograms
• Approximate Diameter: 2300 kilometres
• Approximate Surface Area: 17 million km²
• Average Distance from the Sun: 39.53 Astronomical units
• Rotational Period: 6.39 days
• Revolution Period: 247.7 years
• Axial Tilt: 122.5 degree?s
• Mean Temperature: 37 Kelvin

Pluto has an atmosphere when it is close to perihelion; the atmosphere freezes out as Pluto moves further from the Sun.

Pluto has one natural satellite, Charon. Little is known about Pluto because of its great distance from Earth and because no exploratory satellites have visited Pluto yet.

The planet is named both for the Roman god Pluto, and for the astronomer Percival Lowell, who predicted that a planet would be found beyond Neptune.

Solar system:
Sun - Mercury - Venus - Earth - Mars - Asteroids - Jupiter - Saturn - Uranus - Neptune - Pluto - Comets

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Pluto is the Roman god of the Underworld, who the Greeks called Hades. He abducted Proserpine (Gr. Persephone), and her mother Ceres (Gr. Demeter) caused winter in her grief.

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Pluto is [Mickey Mouse]?'s pet dog. Unlike most of Disney?'s animated animal characters, Pluto does not talk.