Gullies in Hale Crater (False Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunar Explorer Italia)

The MGS-MOC captured 2 examples of gullies on crater walls in which a change occurred between 1999 and 2005.
In each case, one in Terra Sirenum, the other in the Centauri Montes, new light-toned material was deposited during the MGS Mission. These new light-toned deposits may be indicators that water flowed at these two gully sites during the past few years. Naturally, a question arises: are there other gullies at which similar light-toned deposits have formed?

To answer the question, the MOC Team at MSSS reviewed every MOC image ever taken of a Martian Gully. Most of the gullies occur at middle latitudes in both the Northern and Southern Hemispheres. This re-examination turned up several good examples of other light-toned materials deposited in gullies. However, in none of these cases is there a “before” image, with no light-toned material, followed by an “after” image in which new light-toned material had appeared. Thus, one cannot know how long ago these other light-toned deposits formed.
However, these are excellent candidates for future monitoring with orbiter cameras that have sufficient spatial resolution to look for new light-toned deposits, should they form during the coming years.