Spring Fans Bursting from Cracks in Ice
Spring Fans Bursting from Cracks in Ice
ESP_024428_2605  Science Theme: Seasonal Processes
Sand dunes in the North polar region of Mars are covered every winter by a layer of carbon dioxide ice (dry ice). In the springtime the ice on the dunes cracks, often in polygonal patterns.

Once the ice layer has cracked the sand below can escape. It may be blown downwind, landing in fan-shaped deposits on top of the seasonal layer of ice. It may also slide down the sides of the dunes, often the case when the ice ruptures at the crest of the dune.

Written by: Candy Hansen  (3 November 2011)
Acquisition date
12 October 2011

Local Mars time

Latitude (centered)

Longitude (East)

Spacecraft altitude
317.3 km (197.2 miles)

Original image scale range
63.5 cm/pixel (with 2 x 2 binning) so objects ~191 cm across are resolved

Map projected scale
50 cm/pixel

Map projection

Emission angle

Phase angle

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

Solar longitude
14.3°, Northern Spring

For non-map projected images
North azimuth:  108°
Sub-solar azimuth:  307.3°
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   (449MB)

IRB color
map-projected   (234MB)

Black and white
map-projected  (306MB)
non-map           (198MB)

IRB color
map projected  (159MB)
non-map           (197MB)

Merged IRB
map projected  (495MB)

Merged RGB
map-projected  (445MB)

RGB color
non map           (180MB)
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.