Distance from the Sun: 4th planet from the sun, 142 million miles (228 million km)
Type of Planet: Terrestrial (has a hard rocky surface)
What is Mars like?
Mars is the 4th planet from the sun. It is a terrestrial planet which means that it has a hard rocky surface that you could walk on. Mars' surface is dry and much of it is covered with a reddish dust and rocks. When viewed from Earth, Mars appears to be the color red.
Mars has some of the most impressive natural geographical structures in the Solar System. Olympus Mons, a now dormant volcano, is the highest mountain in the Solar System. It is 3 times as high as Mount Everest and towers 16 miles above the Martian surface. Another major geographical structure of Mars is the great canyon, Valles Marineris. This canyon is the biggest in the Solar System. It is 4 miles deep in places and stretches for thousands of miles.
Red and rocky surface of Mars taken from the Pathfinder. Source: NASA.
Weather on Mars
Mars often has huge dust storms with high speed winds. These dust storms are powered by the Sun and can grow to enormous proportions sending dust miles into the atmosphere and covering much of the planet. Some storms are so big they can be seen by amateur astronomers on Earth.
From left to right: Mercury, Venus, Earth, Mars. Source: NASA.
How does Mars compare to Earth?
In many ways, Mars is very similar to Earth. Mars' year and day are very similar to Earth compared to other planets. Mars is a terrestrial planet like Earth. Mars is quite a bit smaller than Earth both in diameter and in mass.
Unlike Earth, Mars has a very thin atmosphere made up mostly of carbon dioxide. As a result, it is much colder on Mars (average of -70 degrees F) than on Earth.
There is evidence that open water in liquid form once existed on the surface of Mars like Earth. Perhaps there was even life on Mars billions of years ago.
How do we know about Mars?
Mars is one of the easiest planets to study from Earth. It is fairly close and, since it is further from the sun than us, it is easy to view in the night sky. The Mariner 4 spacecraft was the first to bring us close up pictures of Mars in 1965. Since then several space probes have visited Mars. The Viking 1, Viking 2, and Pathfinder landers, landed on the surface of Mars and sent us back pictures of the surface. They also analyzed the Martian soil. Mars will likely be the first planet that a human will step foot on.
The Mars rover Curiosity on the surface of the planet. Source: NASA.
Fun Facts about the Planet Mars
It is named after the Roman god of war. The Greeks called the planet "Ares" after their version of the god of war.
The two moons of Mars are named Phobos and Deimos.
Because Mars doesn't have any oceans, it has nearly the same land surface as the Earth.
The Ancient Egyptians called Mars "Har dècher" which means "the red one."
A 100 pound person on Earth would weigh around 38 pounds on Mars.
Some scientists believe that Mars was once covered with water.
Mars is the second smallest planet in the Solar System.
