Named after the Roman God of commerce, Mercury is the closet planet to the Sun in our solar system. However this does not automatically make it the warmest. Mercury has no or negligible atmosphere which means that it has no protection from the Suns rays, however because there is no atmosphere, the heat from the face pointing away from the sun is released back into space. So the face which points to the Sun has a very hot surface and the face pointing away from the Sun has a very cold surface.
Mercury has a very pock marked surface from the bombardment it has sustained over about 4 1/2 billion years. Because Mercury has so little atmosphere, it has not suffered from weather erosion, and so has kept its injuries for all that time.
The Moon and Mercury are very similar in appearances apart from the size of craters that have been created. Mercury is more dense with a greater gravity, and so the craters are not as large or deep as the Moon`s. The extra gravity on Mercury also prevents the debris from impacts travelling as far as it would have on the Moon.
Planetary Information
| Maximum Distance from the Sun | 69.7Mkms |
| Minimum Distance from the Sun | 45.9Mkms |
| Diameter | 4878km |
| Mass | 0.055 |
| Sidereal period | 88d |
| Rotation period | 56.65d |
| Velocity | 47.9km/s |
| Gravity | 0.38 |
| Maximum Temperature | 350 C |
| Minimum Temperature | -170 C |
| Number of Moons | 0 |
| Escape Velocity | 15475 km/h |