Northern Polar Dune Field
Northern Polar Dune Field
ESP_027378_2540  Science Theme: Seasonal Processes
This field of crescent-shaped dunes is located just south of the North Polar layered terrain.

These dunes, known as barchan dunes, usually form where there is a moderate supply of sand and a prevailing wind direction. The “arms” or “horns” of barchan dunes point in the downwind direction and in this case indicate that the prevailing winds blow towards the northwest.

The dunes in the close-up image are approximately 100 meters across and are traversing a bumpy, hard terrain. Polygonal patterns are evident in some areas while numerous meter-scale boulders are strewn throughout the region. The boulders are more numerous in areas where the polygonal patterns are less pronounced. Repeat imaging of this dune field could reveal whether these dunes are presently moving.

Written by: Ginny Gulick (audio by Tre Gibbs)  (11 July 2012)
Acquisition date
29 May 2012

Local Mars time

Latitude (centered)

Longitude (East)

Spacecraft altitude
316.6 km (196.8 miles)

Original image scale range
63.4 cm/pixel (with 2 x 2 binning) so objects ~190 cm across are resolved

Map projected scale
50 cm/pixel

Map projection

Emission angle

Phase angle

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

Solar longitude
117.4°, Northern Summer

For non-map projected images
North azimuth:  101°
Sub-solar azimuth:  327.1°
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   (369MB)

IRB color
map-projected   (202MB)

Black and white
map-projected  (237MB)
non-map           (169MB)

IRB color
map projected  (110MB)
non-map           (154MB)

Merged IRB
map projected  (344MB)

Merged RGB
map-projected  (318MB)

RGB color
non map           (145MB)
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.