Potential Active Processes in Porter Crater
Potential Active Processes in Porter Crater
ESP_040885_1295  Science Theme: Sedimentary/Layering Processes
The extended-mission status of the Mars Reconnaissance Orbiter and the HiRISE camera has greatly increased our understanding of numerous active processes occurring on Mars. By taking carefully planned repeat images of surface, we now have an important record of how the surface evolves for a maximum of 5 Mars years.

This image shows the central peak in Porter Crater. Although there are no repeat images here we can infer several active geologic processes, based on morphologic evidence and lessons learned from past well-monitored sites.

Shallow gullies are located on the south and east facing slopes of the central peak. These features might have been carved by volatiles, such as carbon dioxide frost, sometime in the recent geologic past.

Meanwhile on the northern slopes are several smaller slope features that have a morphology hinting at recurring slope lineae (RSL). Alternatively, these features could be the remnants of past active gullies. Several more HiRISE images would be needed to characterize their behavior and confirm their status as RSL (see “Recurring Slope Lineae in Equatorial Regions of Mars”).

Southward on the slopes below the peak is a large dune field. Dunes show sharp crests with prominent ripples, both signs of actively migrating dunes. Also, we can see dust devil tracks crossing the nearby dusty surfaces and clear evidence for ongoing modification by swirling winds that persistently remove surface dust.

Ongoing operations by HiRISE are dedicated to studying all of the active surface and atmospheric processes operating on Mars.

Written by: Matthew Chojnacki (narration: Tre Gibbs)  (15 July 2015)
Acquisition date
17 April 2015

Local Mars time

Latitude (centered)

Longitude (East)

Spacecraft altitude
251.4 km (156.3 miles)

Original image scale range
50.3 cm/pixel (with 2 x 2 binning) so objects ~151 cm across are resolved

Map projected scale
50 cm/pixel and North is up

Map projection

Emission angle

Phase angle

Solar incidence angle
48°, with the Sun about 42° above the horizon

Solar longitude
327.2°, Northern Winter

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North azimuth:  97°
Sub-solar azimuth:  44.2°
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All of the images produced by HiRISE and accessible on this site are within the public domain: there are no restrictions on their usage by anyone in the public, including news or science organizations. We do ask for a credit line where possible:

NASA’s Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, Calif., manages the Mars Reconnaissance Orbiter for NASA’s Science Mission Directorate, Washington. The HiRISE camera was built by Ball Aerospace and Technology Corporation and is operated by the University of Arizona.