RL and JW
Mercury is a rocky planet that has a solid surface and is very hot. Mercury is the closest planet to the Sun and is the smallest in the Solar System. It is only about one-third the size of Earth. The surface temperature of the side of Mercury closest to the Sun reaches 427 degrees Celsius, a temperature hot enough to melt tin. On the side facing away from the Sun, or the night side, the temperature drops to -183 degrees Celsius.