Mercury

Mercury, closest planet to the sun, revolves around it the fastest, with the shortest year in our solar system-88 days.

Mercury, named for the messenger of the gods-where speed is of the essence!

Only one spacecraft has ever visited this planet, "Mariner 10" in the mid-70's, though a new mission called "Messenger" is planned for the end of this decade.

Mercury's day / night temperature variations are the greatest in the solar system.

Chris Chyba Carl Sagan Chair for the Study of Life in the Universe SETI Institute & Stanford University Mercury is so close to the Sun that it's simply uninhabitable. If it did have an atmosphere it would lose it... the solar wind from the sun, charged particles would strip Mercury's atmosphere quickly. It's just too close to the Sun and it's too small a world.

Revolution	Rotation	Radius	Distance From the Sun
88 Earth days It revolves around the Sun the fastest, with the shortest year in our solar system.	176 Earth days	2,439.7 km	57,910,000 km
Mass	Density	Surface Temperature	Moons
0.3302 x 10 27 grams	5.43 gm/cm3	427° to -173° C Mercury's day and night temperature variation are the greatest in the solar system.	none
Atmosphere	Craters	Volcanoes	Water
mainly argon, neon and helium	Mercury's surface is covered with craters, much like Earth's Moon	Mercury appears to have few if any volcanoes-though there's evidence of plentiful lava flows early in its history.	Mercury had water, but it boiled away to space as the planet got hot enough to melt lead It is believed that water ice is still located in the shaded regions of its pole.

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Missions:  • Messenger (Launch 2004)	Recent Articles:	Additional Links:  • JPL's Solar System Exploration  • The Nine Planets  • Views of the Solar System  • Windows to the Universe