What on Mars is a High Thermal-Inertia Surface?
What on Mars is a High Thermal-Inertia Surface?
ESP_039485_1660  Science Theme: Rocks and Regolith
What do we mean when we describe a surface as having “high thermal inertia”? The term refers to the ability of a material to conduct and store heat, and in planetary science, its measure of the subsurface’s ability to store heat during the day and reradiate it during the night.

What causes thermal inertia? It depends on the composition of the terrain that we’re studying. Here in Coprates Chasma, the site of this observation, we find indications of such high thermal inertia, so an image at high resolution may help us determine the composition and structure to give us an answer.

Coprates Chasma is located in the huge canyon system, Vallis Marineris. For a general overview of thermal inertia, see Nathaniel Putzig’s page.

This caption is based on the original science rationale.

Written by: HiRISE Science Team (narration: Tre Gibbs)  (8 April 2015)
Acquisition date
29 December 2014

Local Mars time

Latitude (centered)

Longitude (East)

Spacecraft altitude
263.7 km (163.9 miles)

Original image scale range
26.4 cm/pixel (with 1 x 1 binning) so objects ~79 cm across are resolved

Map projected scale
25 cm/pixel and North is up

Map projection

Emission angle

Phase angle

Solar incidence angle
45°, with the Sun about 45° above the horizon

Solar longitude
261.7°, Northern Autumn

For non-map projected images
North azimuth:  97°
Sub-solar azimuth:  343.5°
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   (928MB)

IRB color
map-projected   (559MB)

Black and white
map-projected  (441MB)
non-map           (547MB)

IRB color
map projected  (192MB)
non-map           (536MB)

Merged IRB
map projected  (289MB)

Merged RGB
map-projected  (271MB)

RGB color
non map           (562MB)
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.