Mercury is the closest planet to the Sun at 57,910,000 km. It is the smallest of the eight in our system, at a diameter of 4,880 km and it’s mass is 3.30e23 kg. Mercury varies drastictly in it’s temperature, ranging from 90 K to 700 K. Mercury is covered with craters and it is a gray-blue in color. It orbits the sun every 88 Earth Days.