One of the goals of current martian exploration is to search for evidence of extinct (or even extant) life. In recent years, this goal has been interpreted as a search for evidence of water on Mars’ surface. The success of instrumentation (high resolution cameras and infrared spectrometers) on orbiting spacecraft, coupled with in situ data from the MER rovers have revolutionized our understanding of the surface of Mars, the type of rocks and minerals pre-sent, and their stratigraphy [1 and subsequent papers]. It is clear that there has been extensive and intensive aqueous action at different periods in Mars’ history, and evidence for water is, to all intents and purposes, irrefutable. It is now time to define the next phase in the search for life as a search for regions of habitability on Mars [2]. A search for life could also be seen as a search for carbon, as one of the major assumptions that has been made in the search for life on Mars is that any life present is likely to be carbon-based.