The THEMIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. These false color images may reveal subtle variations of the surface not easily identified in a single band image. Today's false color image shows part of Nili Fossae. Dark "blue" is interpreted to be basaltic rock/sand.
Orbit Number: 17546 Latitude: 24.4543 Longitude: 79.8833 Instrument: VIS Captured: 2005-11-28 02:22. http://photojournal.jpl.nasa.gov/catalog/PIA20223