Colorful Knobs in Ariadnes Colles
Colorful Knobs in Ariadnes Colles
PSP_007368_1445  Science Theme: Sedimentary/Layering Processes
This HiRISE image shows great detail of light-toned knobs in a region known as Ariadnes Colles in the southern hemisphere of Mars.

As visible in this false color RGB composite, there are high standing light-toned deposits that are covered by darker material. This darker gray-blue material is most likely dust or sand that once covered the region, was since lithified (cemented), and is now being eroded.

The older bright rock that is now exposed from underneath exhibits raised ridges that are likely fractures that have been filled in with material. The material that filled these fractures is harder than the surrounding rock and takes longer to erode. This causes the fracture fill material to have a raised appearance in the knobs. The CRISM instrument has shown that similar knobs in this region contain minerals with water, indicating that this area contained water at some point in the past.

Written by: Ralph Milliken  (3 March 2008)

This is a stereo pair with PSP_010717_1445.
Acquisition date
21 February 2008

Local Mars time

Latitude (centered)

Longitude (East)

Spacecraft altitude
253.3 km (157.5 miles)

Original image scale range
25.5 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
65°, with the Sun about 25° above the horizon

Solar longitude
35.1°, Northern Spring

For non-map projected images
North azimuth:  97°
Sub-solar azimuth:  46.9°
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   (1066MB)

IRB color
map-projected   (495MB)

Black and white
map-projected  (564MB)
non-map           (599MB)

IRB color
map projected  (189MB)
non-map           (492MB)

Merged IRB
map projected  (229MB)

Merged RGB
map-projected  (231MB)

RGB color
non map           (465MB)
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’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.