South Polar Cap Terrain
South Polar Cap Terrain
ESP_067151_0930  Science Theme: Seasonal Processes
This intriguing, almost cartoon-like terrain is composed of coalescing pits and smooth-topped mesas, forming part of what is known as the Residual South Polar Cap (RSPC) of Mars.

The RSPC is a permanent deposit of carbon dioxide (dry) ice that is several kilometers thick and overlies a much larger water ice cap. This part of the RSPC lies at an elevation of about 6.5 kilometers. The mesas are several kilometers long while the pits range in diameter up to several hundred meters. The dark regions surrounding the mesas are thought to be exposed water ice.

This image was taken during southern summer when the brighter-appearing dry ice cap sublimates (evaporates directly from ice to vapor) exposing the darker, underlying water ice cap. Understanding the seasonal and yearly volumes of carbon dioxide exchange between the surface and the atmosphere provides important insights into Mars’ climate.

Written by: Ginny Gulick  (17 February 2021)
Acquisition date
22 November 2020

Local Mars time

Latitude (centered)

Longitude (East)

Spacecraft altitude
244.6 km (152.0 miles)

Original image scale range
24.6 cm/pixel (with 1 x 1 binning) so objects ~74 cm across are resolved

Map projected scale
25 cm/pixel

Map projection

Emission angle

Phase angle

Solar incidence angle
75°, with the Sun about 15° above the horizon

Solar longitude
319.2°, Northern Winter

For non-map projected images
North azimuth:  159°
Sub-solar azimuth:  49.8°
Black and white
map projected  non-map

IRB color
map projected  non-map

Merged IRB
map projected

Merged RGB
map projected

RGB color
non-map projected

Black and white
map-projected   (442MB)

IRB color
map-projected   (294MB)

Black and white
map-projected  (223MB)
non-map           (246MB)

IRB color
map projected  (99MB)
non-map           (273MB)

Merged IRB
map projected  (111MB)

Merged RGB
map-projected  (101MB)

RGB color
non map           (233MB)
10K (TIFF)

B&W label
Color label
Merged IRB label
Merged RGB label
EDR products

IRB: infrared-red-blue
RGB: red-green-blue
About color products (PDF)

Black & white is 5 km across; enhanced color about 1 km
For scale, use JPEG/JP2 black & white map-projected images

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/JPL/University of Arizona

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.