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"
At the Summit of Olympus Mons
26/05/2004
From martian orbit, the Mars Express cameras looked down on the largest volcano in the solar system. The result was this stunningly detailed overhead view of the caldera or summit crater region of Olympus Mons. Fittingly named for the lofty abode of the gods of Greek mythology, Olympus Mons rises 21 kilometers above the surrounding plain or to about 3 times the height of Mt. Everest. The area pictured is 102 kilometers across and the caldera pits are up to 3 kilometers deep. For comparison, hawaiian volcanic calderas range up to 18 kilometers in diameter. Outlined by steep cliffs, Olympus Mons itself is about 600 kilometers in diameter.