Snegidhi.com

Back to Home >>

Mission - Mercury

     23rd May' 2009

Mercury is the innermost and smallest planet in the Solar System, orbiting the Sun once every 87.969 days. The orbit of Mercury has the highest eccentricity of all the Solar System planets, and it has the smallest axial tilt.

Mercury is similar in appearance to the Moon: it is heavily cratered with regions of smooth plains, has no natural satellites and no substantial atmosphere. Mercury’s surface is overall very similar in appearance to that of the Moon, showing extensive mare-like plains and heavy cratering, indicating that it has been geologically inactive for billions of years.

Data from the October 2008 flyby of MESSENGER gave researchers a greater appreciation for the jumbled nature of Mercury's surface. Mercury's surface is more heterogeneous than either Mars or earth's Moon, both of which contain significant stretches of similar geology, such as maria and plateaus. Craters on Mercury range in diameter from small bowl-shaped cavities to multi-ringed impact basins hundreds of kilometers across.

The mean surface temperature of Mercury is 442.5 K, but it ranges from 100 K to 700 K, due to the absence of an atmosphere. On the dark side of the planet, temperatures average 110 K. Despite the generally extremely high temperature of its surface, observations strongly suggest that ice exists on Mercury. The icy regions are believed to contain about 10^14–10^15 kg of ice.

Back to Home >>