The Thermal Emission Spectrometer on Mars Global Surveyor mapped Mars at longer wavelengths, and with a different purpose, than the earlier photographic atlases composed by the Viking Orbiters and Mariner 9. This map is actually more directly comparable to the drawings made by Earth-based astronomers, because it focuses on albedo variations (differences in brightness and darkness from place to place on the surface) as opposed to the geomorphology revealed by cast shadows.

NASA / JPL / ASU / Phil Stooke