Sinuous Ridges and Meanders
Sinuous Ridges and Meanders
ESP_034189_1740  Science Theme: Fluvial Processes
These ridges are thought to be old river channels, but wind erosion has created inverted topography. What was low (the channel bottoms) was more resistant to erosion, so now it is relatively high.

In a closeup image, we see a cutoff meander. This forms as a river cuts its outer bank and curves more and more, until it decides to take a “short-cut.” The abandoned channel may have formed an oxbow lake, when water was present. This type of river system forms slowly over time, unlike the catastrophic flood channels seen elsewhere on Mars.

Be sure to look at the stereo anaglyph with red-green glasses at full resolution.

Written by: Alfred McEwen (narration: Tre Gibbs)  (29 January 2014)

This is a stereo pair with ESP_034044_1740.
Acquisition date
11 November 2013

Local Mars time

Latitude (centered)

Longitude (East)

Spacecraft altitude
267.3 km (166.2 miles)

Original image scale range
56.9 cm/pixel (with 2 x 2 binning) so objects ~171 cm across are resolved

Map projected scale
50 cm/pixel and North is up

Map projection

Emission angle

Phase angle

Solar incidence angle
49°, with the Sun about 41° above the horizon

Solar longitude
48.1°, Northern Spring

For non-map projected images
North azimuth:  96°
Sub-solar azimuth:  39.2°
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   (429MB)

IRB color
map-projected   (232MB)

Black and white
map-projected  (224MB)
non-map           (220MB)

IRB color
map projected  (103MB)
non-map           (205MB)

Merged IRB
map projected  (457MB)

Merged RGB
map-projected  (426MB)

RGB color
non map           (195MB)
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.