Mars can be seen, with the naked eye, as a bright, red, object. Mars has a rugged surface with mountains, valleys and large craters. The volcanic mountain, Olympus Mons, is the largest mountain in the solar system, at 27 km high.

     Mars has always fascinated people. Its red, fiery appearance was mysterious and intriguing. Mars has only a quarter the surface area of Earth and only 1/10th the mass (though because it lacks oceans the area of Mars's accessible dry land is approximately equal to that of the Earth's dry land). Mars has two small moons, Phobos and Deimos, both small and oddly shaped, possibly captured asteroids. Mars has polar ice caps that contain frozen water and carbon dioxide. An extinct volcano, Olympus Mons, is, at 27 km, the tallest mountain in the solar system. Mars's atmosphere is very thin: the surface air pressure is only 7.5 millibars compared to an average 1013 millibars on Earth. The atmosphere on Mars is 95% carbon dioxide, 3% nitrogen, 1.6% argon, with only a trace of oxygen and water.

Mountains and craters scar the rugged terrain of Mars. The dust, an iron oxide, gives the planet its reddish cast. A thin atmosphere and an elliptical orbit combine to create temperature fluctuations from -207 degrees to a comfortable 80 on summer days. At the top and bottom of the planet are poles just like on Earth. During the Martian winter, ice caps can be seen at the poles.

Mars is much smaller than Earth, but recent research shows that it once had flowing rivers. Mars also has a canyon that stretches over 2000 miles. Mars has many craters which were formed by meteorites or asteroids hitting it. Mars also has some of the tallest volcanoes and some of the deepest valleys in our solar system. Mars has two moons, Phobos and Deimos which have unusual shapes. Scientists think these potato-shaped moons were once asteroids captured by Mars' gravitational pull.