Looking at Martian Salts and Clays
Looking at Martian Salts and Clays
PSP_005811_1470  Science Theme: Composition and Photometry
This 3D perspective view is a composite of both HiRISE and data from CRISM, another instrument onboard MRO. This view covers a small patch of ancient Martian real estate in Terra Sirenum.

CRISM collects spectral data that can be used as a chemical fingerprint for the upper most surface. This information suggests that this small patch of surface is covered with salts (chlorides) represented in green and water-rich clays that appear in blue.

CRISM colors can be added to high-resolution images to enhance our knowledge of these materials. They also match nicely with the surface features in our HiRISE image. For example, a fissure near the center of the image may be a a clue to the origin of the salts. The fissure may be a fracture where warm salt-laden water may have welled up, erupted and ponded on the surface. These waters then evaporated leaving the salt-rich deposits behind.

Written by: Livio Leonardo Tornabene  (26 November 2018)

This is a stereo pair with PSP_006668_1470.
Acquisition date
23 October 2007

Local Mars time

Latitude (centered)

Longitude (East)

Spacecraft altitude
252.6 km (157.0 miles)

Original image scale range
25.4 cm/pixel (with 1 x 1 binning) so objects ~76 cm across are resolved

Map projected scale
25 cm/pixel and North is up

Map projection

Emission angle

Phase angle

Solar incidence angle
40°, with the Sun about 50° above the horizon

Solar longitude
335.4°, Northern Winter

For non-map projected images
North azimuth:  97°
Sub-solar azimuth:  32.7°
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   (802MB)

IRB color
map-projected   (402MB)

Black and white
map-projected  (363MB)
non-map           (494MB)

IRB color
map projected  (137MB)
non-map           (391MB)

Merged IRB
map projected  (195MB)

Merged RGB
map-projected  (196MB)

RGB color
non map           (384MB)
Map-projected, reduced-resolution
Full resolution JP2 download
Anaglyph details page

DTM details page

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.