View a photo provided by Astronomy Picture of the Day of the Martian surface and its craters. Learn how the craters are classified.

High-resolution picture taken by the Mars Global Surveyor robot spacecraft of a region within Mars' Newton Crater which is riddled with gullies.

Supplies a Mars Global Surveyor image of Olympus Mons, the Martian volcano that holds the title of largest volcano in the Solar System.

Examine a photograph, taken by the Mars Global Surveyor, of a large dust storm erupting out from the north polar cap of Mars.

Enjoy a synthesized color image from the Mars Global Surveyor of the Red Planet's 201-kilometer-wide Lowell crater.

Picture captures the gullies in a three-kilometer-wide area in the south facing wall of a crater in southern Noachis Terra.

Mars Global Surveyor picture shows the yardangs, or wind-eroded ridges, which pepper the eastern Aeolis region of the southern Elysium Planitia.

Features a map that depicts the rover Sojourner's movements on the surface of Mars, and offers images taken by the rover cameras.

Enjoy a photo album, slide show, and MPEG and QuickTime movies taken by NASA's visitor to the Red Planet.