Dune Footprints in Hellas
NASA/JPL/University of Arizona
Dune Footprints in Hellas
ESP_059708_1305  Science Theme: Landscape Evolution
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These curious chevron shapes in southeast Hellas Planitia are the result of a complex story of dunes, lava, and wind.

Long ago, there were large crescent-shaped (barchan) dunes that moved across this area, and at some point, there was an eruption. The lava flowed out over the plain and around the dunes, but not over them. The lava solidified, but these dunes still stuck up like islands. However, they were still just dunes, and the wind continued to blow. Eventually, the sand piles that were the dunes migrated away, leaving these “footprints” in the lava plain. These are also called “dune casts” and record the presence of dunes that were surrounded by lava.

Enterprising viewers will make the discovery that these features look conspicuously like a famous logo: and you’d be right, but it’s only a coincidence.

Written by: Ross Beyer (audio: Tre Gibbs)  (10 June 2019)
 
Acquisition date
22 April 2019

Local Mars time
14:27

Latitude (centered)
-49.325°

Longitude (East)
85.331°

Spacecraft altitude
256.8 km (159.6 miles)

Original image scale range
53.6 cm/pixel (with 2 x 2 binning) so objects ~161 cm across are resolved

Map projected scale
50 cm/pixel and North is up

Map projection
Equirectangular

Emission angle
16.5°

Phase angle
74.7°

Solar incidence angle
64°, with the Sun about 26° above the horizon

Solar longitude
14.9°, Northern Spring

For non-map projected images
North azimuth:  95°
Sub-solar azimuth:  54.9°
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non-map           (141MB)

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non-map           (144MB)

Merged IRB
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EDR products
HiView

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IRB: infrared-red-blue
RGB: red-green-blue
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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/University of Arizona

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.