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"
Volcanos on Mars: Elysium Region
30/07/1998
This "synthetic color" image swath of the Elysium Volcanic Region of Mars was recorded by Mars Global Surveyor's wide angle camera on July 2. North is up and the sun illuminates the scene from the lower right. Bright clouds hover near the northern most dome-shaped volcano Hecates Tholus. The shield volcano Elysium Mons lies about 250 miles south near the image center, and farther south lies another dome-shaped volcano, Albor Tholus, with a broad summit basin or caldera. Even though Mars is just half the size of planet Earth, it is known for its volcanos - the largest of which dwarf their terrestrial counterparts.