Sinuous Ridges in the Aeolis/Zephyria Region
Sinuous Ridges in the Aeolis/Zephyria Region
ESP_020528_1750  Science Theme: Fluvial Processes
The ridges in this image may be the inverted (high instead of low) remains of old river channels.

When a river flows over a plain, it often creates a channel that can meander back and forth. Sometimes if a lava flow passes through the same area, the lava can also flow down the channels and harden on the bed. When the landscape gets eroded at some later time, the plains are stripped down, but the lava in the channels stays high, and you can get ridges that mark the locations of where riverbeds were prior.

The ridges in this image show a very sinuous or meandering form, indicating that they may have once been river channels that were filled in. We can study these ridges to try and determine how much water might have flowed through this system.

Written by: Ross A. Beyer  (26 January 2011)

This is a stereo pair with ESP_020673_1750.
Acquisition date
13 December 2010

Local Mars time

Latitude (centered)

Longitude (East)

Spacecraft altitude
267.8 km (166.4 miles)

Original image scale range
27.1 cm/pixel (with 1 x 1 binning) so objects ~81 cm across are resolved

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25 cm/pixel and North is up

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Solar incidence angle
54°, with the Sun about 36° above the horizon

Solar longitude
197.5°, Northern Autumn

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North azimuth:  97°
Sub-solar azimuth:  359.9°
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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.