Mars
Mars is the fourth planet from the Sun and the seventh largest in the Solar System. A cold, dusty desert world with a thin atmosphere (mostly CO₂), the planet features extinct volcanoes, deep canyons, polar ice caps, and seasons. Mars has two small moons (Phobos and Deimos), a day just over 24 hours long, and a year lasting about 687 Earth days. It is a prime focus of robotic exploration and studies about past water and habitability.
Source: science.nasa.gov
APODs including "Mars"
Volcanic Bumpy Boulder on Mars
15/05/2006
What created this unusually textured rock on Mars? Most probably: a volcano. Dubbed Bumpy Boulder, the strange stone measuring just under a half-meter high was found by the robotic Spirit rover currently rolling across Mars. Pits on the ragged rock are likely vesicles and arise from hot gas bubbling out of hot rock ejected by an active Martian volcano. Several similar rocks are visible near Bumpy Boulder that likely have a similar past. The above true-color image was taken about one month ago. The Spirit rover, now in its third year of operation on Mars, is weathering the low sunlight winter of Mar's northern hemisphere on a hillside slope in order to maximize the amount of absorbable battery-refreshing sunlight.