Mercury Mercury Mercury is the planet that is closest to the Sun. We don't have lots of data about Mercury, but there is some. This turns out not to be true. There are some differences, however. Mercury has a planet-wide system of fault scarps and fault scarps.
Faults are fractures in a rock along which movement has occurred.
Scarps are cliffs that form when rocks move along a fault. Thrust faults happen when rocks are compressed, or squeezed. The resulting basin is half the size of Mercury, and is called the Caloris Basin . Mercury has polar ice caps, like Earth and Mars. However, it is unlikely that the core is liquid, because Mercury has a very weak magnetic field.