Polygonal Patterned Ground
Polygonal Patterned Ground
ESP_016641_2500  Science Theme: Glacial/Periglacial Processes
From a distance, the floor of this crater looks like a giant honeycomb or spider web. The intersecting shapes, or polygons, commonly occur in the northern lowlands of Mars.

The polygons in this “patterned ground” are easy to see because their edges are bound by troughs or ridges covered by bright frost relative to their darker, frost-free interiors. Patterned ground on Mars is thought to form as the result of cyclic thermal contraction cracking in the permanently frozen ground.

Scientists study polygonally-patterned ground on Mars because the occurrence and physical characteristics of the polygons helps us understand the recent and past distribution of ice (frozen water) in the shallow subsurface. These features also provide clues about climate conditions. The cutout shows smaller polygons within larger polygons.

Written by: Sharon Wilson  (7 April 2010)
Acquisition date
13 February 2010

Local Mars time

Latitude (centered)

Longitude (East)

Spacecraft altitude
313.9 km (195.1 miles)

Original image scale range
31.6 cm/pixel (with 1 x 1 binning) so objects ~95 cm across are resolved

Map projected scale
25 cm/pixel

Map projection

Emission angle

Phase angle

Solar incidence angle
56°, with the Sun about 34° above the horizon

Solar longitude
51.0°, Northern Spring

For non-map projected images
North azimuth:  98°
Sub-solar azimuth:  322.4°
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   (1296MB)

IRB color
map-projected   (573MB)

Black and white
map-projected  (766MB)
non-map           (555MB)

IRB color
map projected  (265MB)
non-map           (442MB)

Merged IRB
map projected  (384MB)

Merged RGB
map-projected  (356MB)

RGB color
non map           (395MB)
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’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.