The nearest planet to the Sun, Mercury is a heavily cratered planet with a volume and mass of only 1/18th that of the Earth. It is situated 58 million km from the Sun and orbits in a period of 88 days. The planet is considerably dense for its size and has a gravitational pull equal to approximately a third that of the Earth.
Recently NASA's Messenger space probe visited the planet Mercury and returned details pictures of the surface.
Related entries: Deimos
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