What is Mars?

Mars is the fourth planet from the Sun and the next planet beyond Earth. It is, on average, more than 142 million miles from the Sun. Mars turns on its axis more slowly than Earth does. So, a day on Mars is 24.6 hours. Since this planet is farther from the Sun than Earth, one revolution of Mars around the Sun is a longer trip. So, a year on Mars is 687 Earth days.

Mars is about half the size of Earth. Mars is known as the Red Planet because the iron oxide chemicals in its soil look like rust.