Imaging Data of Slope Streaks on Mars: Changes, Fading, Resurfacing, and Dust Transport

Grant #: NNX10AQ24G
Senior Scientist: Cynthia Phillips

Dark slope streaks represent one of the most dynamic geological processes currently affecting the Martian surface. New slope streaks have been identified in comparisons between Viking and Mars Orbiter Camera (MOC) images, and new streaks have even formed in between subsequent MOC observations. The High Resolution Imaging Science Experiment (HiRISE) camera on the Mars Reconnaissance Orbiter (MRO) spacecraft has revealed the detailed morphology of slope streaks, yielding new insight into their formation and fading. 

Our objective in this work is to determine the quantity and frequency of surface change related to slope streaks. We will do this by using images and spectral data to study the formation and changes in slope streaks over time, looking in particular at quantitative changes due to fading. We will primarily use data from MOS and from HiRISE. We will use our observations and measurements to learn about the brightness of newly-deposited dust, and we will also estimate dust deposition rates in the bright, low thermal inertia regions where slope streaks form. 

The expected significance of this work is a quantitative measure of the net resurfacing rate and dust transport produced through slope streak formation and fading. Our work will also provide an improved understanding of the mechanisms responsible for the on-going formation of these features. Thus, this work will enhance knowledge of Mars' present-day geological processes and help us understand global and seasonal climate variations. One of the possible classes of slope streak formation mechanisms requires liquid water or brines near the surface. In accordance with current Mars exploration goals, which include "following the water" to sites of astrobiological significance, the possibility that dark slope streaks could form in the presence of water makes them of particularly high interest.