Frosty Northern Dunes
NASA/JPL-Caltech/UArizona
Frosty Northern Dunes
ESP_024265_2535  Science Theme: 
It is early spring in the Northern Hemisphere of Mars. These barchan dunes are covered with a layer of seasonal carbon dioxide ice (dry ice). Bluish cracks in the ice are visible across the top of some of the dunes.

Dark fan-shaped deposits around the edges of the dunes are at spots where the ice has sublimated (gone directly from ice to gas) and the ice layer has ruptured, allowing the sand from the dune to escape out from under the ice. The sand is then free to be blown by the wind.

Written by: Candy Hansen  (3 November 2011)
 
Acquisition date
30 September 2011

Local Mars time
13:44

Latitude (centered)
73.319°

Longitude (East)
355.126°

Spacecraft altitude
317.4 km (197.2 miles)

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

Map projected scale
25 cm/pixel

Map projection
Polarstereographic

Emission angle
1.8°

Phase angle
72.9°

Solar incidence angle
72°, with the Sun about 18° above the horizon

Solar longitude
8.2°, Northern Spring

For non-map projected images
North azimuth:  101°
Sub-solar azimuth:  307.4°
JPEG
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

JP2
Black and white
map-projected   (853MB)

IRB color
map-projected   (452MB)

JP2 EXTRAS
Black and white
map-projected  (334MB)
non-map           (392MB)

IRB color
map projected  (115MB)
non-map           (302MB)

Merged IRB
map projected  (217MB)

Merged RGB
map-projected  (215MB)

RGB color
non map           (275MB)
ADDITIONAL INFORMATION
B&W label
Color label
Merged IRB label
Merged RGB label
EDR products
HiView

NB
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

USAGE POLICY
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-Caltech/UArizona

POSTSCRIPT
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.