What is Mercury like?
The temperature variations on Mercury are extreme. The side of Mercury that faces the Sun is incredibly hot and can reach 450 degrees Celsius. The side of Mercury that faces away from the Sun is very cold and can reach as low as -170 C.
The surface of Mercury is covered with craters from impacts of asteroids and other objects. Asteroids are small rocky objects that orbit the Sun.
Mercury has an iron core that is roughly 2400 miles wide. The outer shell is about 400 miles thick.
The diameter of Mercury is 3031 miles. Its distance from the Earth is 57 million miles.
Mercury rotates very slowly. A day on Mercury is as long as 59 Earth days. There is no wind or weather on Mercury as it has no atmosphere. It is a terrestrial planet which means it has a rocky surface.
The first space probe was sent to visit Mercury in 1975. It was called Mariner 10.
