Terby Crater
Terby Crater
PSP_006752_1525  Science Theme: Future Exploration/Landing Sites
Terby Crater was suggested as a possible landing site for the Mars Science Laboratory rover mission. It is a large crater blasted into the northern rim of the gargantuan Hellas Basin. Both of these holes in the crust of Mars were formed by impacts with asteroids or comets early in the planet’s geologic history.

Large impacts excavate material from deep within the crust, allowing a rover to access rocks that otherwise would require a massive drilling rig. Since the interior of Mars is warm enough for liquid water, these rocks are of great interest in the search for possible ancient life on the Red Planet.

As this HiRISE image shows, Terby Crater is interesting for additional reasons. The curving ridges most prominent near the center of the image look like stream channels. However, unlike normal channels, the interior is higher than the surroundings. One way features like this form on Earth is called “topographic inversion.” Stream beds can become lined with larger gravels or cobbles, making them quite resistant to erosion, so with time, the surroundings are removed and the originally low channel is left standing high (and dry).

Another way similar features form is when a stream is flowing underneath a glacier. In this case the liquid water is confined by ice on either side and the sediments can build up. When the ice is removed, a ridge of these sediments is left behind. These are called “eskers” by geologists. While further examination of this and similar HiRISE images may be able to distinguish between these possibilities, a rover would allow more detailed studies.

Written by: Laszlo P. Keszthelyi  (6 February 2008)

This is a stereo pair with PSP_005618_1525.
Acquisition date
04 January 2008

Local Mars time

Latitude (centered)

Longitude (East)

Spacecraft altitude
258.1 km (160.4 miles)

Original image scale range
27.4 cm/pixel (with 1 x 1 binning) so objects ~82 cm across are resolved

Map projected scale
25 cm/pixel and North is up

Map projection

Emission angle

Phase angle

Solar incidence angle
51°, with the Sun about 39° above the horizon

Solar longitude
12.7°, Northern Spring

For non-map projected images
North azimuth:  97°
Sub-solar azimuth:  41.2°
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   (1848MB)

IRB color
map-projected   (870MB)

Black and white
map-projected  (1081MB)
non-map           (948MB)

IRB color
map projected  (394MB)
non-map           (831MB)

Merged IRB
map projected  (505MB)

Merged RGB
map-projected  (514MB)

RGB color
non map           (787MB)
Map-projected, reduced-resolution
Full resolution JP2 download
Anaglyph 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.