Physics
Scientific paper
Dec 2008
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2008agufm.p53a1434g&link_type=abstract
American Geophysical Union, Fall Meeting 2008, abstract #P53A-1434
Physics
5415 Erosion And Weathering, 5445 Meteorology (3346), 5470 Surface Materials And Properties, 6225 Mars
Scientific paper
The wheel tracks left by the MER rovers Spirit and Opportunity are unique artificial markings on the surface of Mars. The tracks stretch several kilometers across diverse terrain in two widely separated regions of the planet. The initial appearance and characteristics of the tracks were well documented by the science and navigation cameras aboard the vehicles at the time the tracks were formed. Orbital observations by Mars Global Surveyor and now Mars Reconnaissance Orbiter document the erasure of the tracks over a period of more than two Mars years. We are studying the erasure of the rover tracks as a means to better understand the mechanisms and time-scales of aeolian degradation on Mars. Spirit's wheels left conspicuous dark tracks in the dust-mantled soil of Gusev crater. Low albedo sand and gravel were exposed from beneath the bright dust mantle along Spirit's traverse from its landing site across the Columbia Hills. High albedo, silica-rich soils were ploughed up near Home Plate by the rover's stuck right front wheel. MOC images show that the tracks near the landing site began to fade gradually in the weeks after they were made. Atmospheric dust fallout and summertime dust-devils rendered Spirit's tracks invisible before the arrival of MRO. Only two small sections of tracks from Spirit's traverse to Home Plate can still be seen in recent HiRISE images, on the southern flanks of Husband Hill and in the corridor west of Mitcheltree Ridge. Spirit witnessed the episodic erasure of its tracks at the height of the global dust storm of 2007, when strong surface winds blew away the tracks and shifted the soil surrounding the rover over a period of just days. Opportunity's tracks across Meridiani Planum to Victoria crater were barely visible at the time that they were made, and had largely disappeared before the arrival of MRO. Opportunity's tracks are slightly brighter than the undisturbed surface because the wheels press the darker hematite spherules into the soft soil. Only two short sections of pre-2006 tracks remain visible in recent HiRISE images, near the craters Fram and Erebus. However, the rover left conspicuous bright tracks in the smooth annulus surrounding Victoria crater as she traversed the crater's northern rim. Surprisingly, these tracks were scarcely altered by the 2007 dust storm, despite clear changes in the pattern of wind streaks emanating from the crater. Understanding the time-scales and mechanisms of erasure of the rover tracks is important for constraining the age of the many pristine impact craters that have been discovered by MRO. In turn, this knowledge lets us place bounds on the present day bombardment rate of Mars.
Arvidson Ray
Bell James
Bridges Nathan
de Souza Paulo
Geissler Paul Eric
No associations
LandOfFree
Constraints on Aeolian Degradation Rates on Mars from Erasure of Rover Tracks does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Constraints on Aeolian Degradation Rates on Mars from Erasure of Rover Tracks, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Constraints on Aeolian Degradation Rates on Mars from Erasure of Rover Tracks will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1239322