MARS

MASS: 11% of Earth's
DIAMETER: 4,217 miles
ROTATION: 24 hours, 37 minutes
ORBIT AROUND SUN: 687 Earth days

Mars the fourth planet from the sun, also known as the Red Planet due to the iron oxide (rust) in the soil, is the only planet most like Earth. It has polar ice caps, made of frozen carbon dioxide (dry ice), that grow and recede with the change of seasons, and markings that appear to be similar to water channels on Earth. It is evident that water played a major role in shaping the planet into what it looks like today. Evidence of erosion and dry riverbeds indicate that there once was water on the planet millions of years ago. Today, the temperature is too cool and the atmosphere too thin for water to exist on the surface. However, water could still exist in the subsurface reservoirs. Life forms of any sort haven't been found on Mars today but there may be fossils of past life during a time when the climate was warmer and there was water.Mars has a dense iron core, surrounded by mantle of molten rock. The crust is several dozen miles thick but it is twice as thick in the southern hemisphere. Indicating that the northern hemisphere has been much hotter, more recently than in the south. The thin atmosphere is made of a mixture of carbon dioxide (95%), nitrogen (3%), argon and other gases (1%). The surface temperature ranges from -190 degrees F to 90 degrees F.Martian tectonism, the formation and change of a planet's crust, differs from Earth's. Earth's tectonics involve sliding plates that grind against each other or spread apart in the seafloors. Martian tectonics seem to be vertical, with hot lava pushing upwards through the crust to the surface.Periodically, great dust storms take place, equivalent to a hurricane. These storms form dunes, wind streaks, and wind carved features. Mars also has some remarkable geological characteristics. Valles Marineris, is the largest canyon in the solar system. If it were on the Earth it would span the United States, from New York to California. It is about 1,300 miles long, 310 miles wide and about 5 miles deep. Arizona's Grand Canyon could easily fit in one of the side canyons. Mars also has the largest volcano of the solar system, Olympus Mons. It is so large that it throws off the planet's spherical shape. It is three times taller than Mount Everest. It rises above Mars' surface 82,000 miles and the base is the size of Missouri.Mars has two potato shaped moons, Phobos and Demos. No one is sure how they came to orbit Mars but scientists believe that they were asteroids that were sucked into orbit by Mars' gravity.