Dunes of the Southern Highlands
NASA/JPL-Caltech/UArizona
Dunes of the Southern Highlands
ESP_049371_1380  Science Theme: Aeolian Processes
Sand dunes are scattered across Mars and one of the larger populations exists in the Southern hemisphere, just west of the Hellas impact basin. The Hellespontus region features numerous collections of dark, dune formations that collect both within depressions such as craters, and among “extra-crater” plains areas.

This image displays the middle portion of a large dune field composed primarily of crescent-shaped “barchan” dunes. Here, the steep, sunlit side of the dune, called a slip face, indicates the down-wind side of the dune and direction of its migration. Other long, narrow linear dunes known as “seif” dunes are also here and in other locales to the east.

NB: “Seif” comes from the Arabic word meaning “sword.”

Written by: Matt Chojnacki (narration: Tre Gibbs)  (23 March 2017)
 
Acquisition date
06 February 2017

Local Mars time
14:15

Latitude (centered)
-41.491°

Longitude (East)
44.515°

Spacecraft altitude
252.4 km (156.9 miles)

Original image scale range
25.5 cm/pixel (with 1 x 1 binning) so objects ~77 cm across are resolved

Map projected scale
25 cm/pixel and North is up

Map projection
Equirectangular

Emission angle
6.2°

Phase angle
32.5°

Solar incidence angle
37°, with the Sun about 53° above the horizon

Solar longitude
312.6°, Northern Winter

For non-map projected images
North azimuth:  97°
Sub-solar azimuth:  34.6°
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   (645MB)

IRB color
map-projected   (378MB)

JP2 EXTRAS
Black and white
map-projected  (298MB)
non-map           (391MB)

IRB color
map projected  (118MB)
non-map           (315MB)

Merged IRB
map projected  (160MB)

Merged RGB
map-projected  (152MB)

RGB color
non map           (318MB)
BONUS
4K (TIFF)
8K (TIFF)

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.