My flickr contact NASA posted this amazing image of Mars taken by the Viking 1 spacecraft in 1976.

“During its examination of Mars, the Viking 1 spacecraft returned images of Valles Marineris, a huge canyon system 5,000 km long, up to 240 km wide, and 6.5 km deep, whose connected chasma or valleys may have formed from a combination of erosional collapse and structural activity. This synthetic oblique view shows Ophir Chasma, the northern most one of the connected valleys of Valles Marineris; north toward top of frame; for scale, the large impact crater in lower right corner is 30 km (18 miles) wide.”