Image mercury


Mercury is the innermost planet in the Solar System, its average distance from the Sun is about 58 million kilometres, about 100 billion footsteps. It is also smaller than all the other planets.

The figure shows its desert-like surface covered in craters and enormous slopes, some of which are three kilometres deep and hundreds of kilometres long. Mercury has no atmosphere and its dusty, rocky surface resembles that of the Moon. The empty parts on the left are flat plains, the scattered dots are small mountains or simply hills, while the dots that form circular shapes are craters.

The craters were formed, during the Solar System’s violent phase, when meteorites crashed into its surface. Mercury and the Moon are not the only two planets to have collided with meteorites, the others have, too. However, the impact is far less violent on planets with atmospheres, because the colliding body is slowed down by the atmospheric friction and turned into vapour. The atmospheres slowly erodes the surface of the planet which erases all traces of the impact.

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