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"
Spirit's 3D View Toward Sleepy Hollow
06/01/2004
Working late, tired mission members nicknamed the smooth-looking depression to the left of center in this image from the martian surface, Sleepy Hollow. The picture is a portion of the 3D panorama of the Spirit rover's landing site released yesterday, constructed with data from the Mars rover's navigation cameras. Use red/blue glasses, red for the left eye, to get the 3D effect. Sleepy Hollow is estimated to be around 9 meters (30 feet) in diameter and about 12 meters (40 feet) away. Possibly an impact crater, the martian surface feature is a tantalizing potential site for a future visit when the golf cart-sized robotic rover ventures forth. Covered with solar arrays, the rear deck of the rover is also visible in this view along with the top of an antenna at the right. An innovative camera calibration target, a martian sundial, can be seen left of the antenna, mounted near the edge of the rover's deck.