Mercury

Mercury, the planet nearest the Sun, is also the smallest planet in the Solar System. Only slightly larger than the Earth's moon, Mercury's surface is covered with craters. This tiny planet does not have any rings or moons.

Visit another planet: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Dwarf Planets
This historic image is the first ever taken from a spacecraft in orbit about <a href="/mercury/mercury.html">Mercury</a>, the innermost planet of the solar system.  Taken on 3/29/2011 by <a href="/space_missions/robotic/messenger/messenger.html">MESSENGER</a>, it shows numerous craters across the <a href="/mercury/Interior_Surface/Surface/surface_overview.html">surface</a> of the planet.  Temperatures there can reach over 800F because Mercury is so close to the Sun and rotates so slowly.  MESSENGER entered orbit around Mercury earlier in March 2011.<p><small><em>NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington</em></small></p><a href="/mercury/mercury.html">Mercury</a>, the innermost planet of the solar system, is a little bigger than the Earth's Moon. The <a href="/mercury/Interior_Surface/Surface/surface_overview.html">surface</a> of the planet is covered with craters, like the Moon, but temperatures there can reach over 800&deg;F because Mercury is so close to the Sun and rotates so slowly.  This picture was taken by the <a href="/space_missions/robotic/messenger/messenger.html">MESSENGER spacecraft</a> in October 2008.<p><small><em>Image courtesy of NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington.</em></small></p>

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