The Red Planet

The Red Planet

Mars is the fourth planet from the Sun. It is named after the ancient Roman god of war. Since the planet is red in color, it also called the “red planet.”

Mars is half the size of Earth. Its thin air is made up mainly of carbon dioxide and other gases, so we wouldn’t be able to breathe it. And the Martian surface is much colder than Earth’s is. Two small moons, Phobos and Deimos, orbit Mars.

The first spacecraft to fly close to Mars was Mariner 4, in 1965. In the 1970s two Viking spacecraft landed there, and in July 1997 Mars Pathfinder set down. These efforts sent back from Mars soil sample reports, pictures, and other data—but no proof of life.

Because of similarities between Mars and Earth, however, scientists think there could be some form of life on Mars. Like Earth, Mars has ice caps at both poles. But its ice caps are composed mostly of solid carbon dioxide, or dry ice. Liquid water has not been seen on the surface of Mars. However, billions of years ago there may have been large lakes or even oceans on Mars.

Also like Earth, Mars has different seasons. Mars takes 687 Earth days to go around the Sun once. This means its year is almost twice as long as ours. But since it spins on its axis once every 24 hours and 37 minutes, its day is just about the same.

Despite being small, Mars has the largest volcano in our solar system, Olympus Mons. It stands about three times higher than Earth’s highest point, Mount Everest, and covers an area just a bit smaller than the entire country of Poland.