Mercury is the planet closest to the sun. It can be seen just before or after sunset as a silvery star like object. Mercury dry and airless as a result of its close distance to the sun. It orbit around the sun takes about 59 days to complete. There are many craters in the dessert like crust of the planet, like on our moon.	Mercury has a red color, like Mars.
Craters on Mercury	Of these many craters 230 have been given a name! The biggest is called Beethoven and measures 625 km across. Astronomers think, that new craters are still being formed on its surface. The surface temperature is approximately 467 degrees Celsius. The atmosphere is very thin, which makes it hard to analyze. The reason is the small mass of Mercury, which results in a low gravity. It is not able to retain a proper atmosphere.
The internal structure of Mercury must have a resemblance to that of the earth. Its diameter is 3600 km. Just like earth it has a crust, but is never thicker than only 66 km. The distance to the sun is 57.91 km.	A ver faint image of Mercury.