Sinuous Pits on Flank of Ascraeus Mons
Sinuous Pits on Flank of Ascraeus Mons
PSP_005387_1935  Science Theme: Volcanic Processes
Troughs on the northeast flanks of Ascraeus Mons, one of the volcanoes on the Tharsis Rise, are the main points of interest in this observation.

The troughs are non-linear and intersecting, and appear to be of different depths. With several exposed layered sequences of lava flows (see subimage, approximately 350 meters across), the troughs possibly mark the paths of these ancient flows that created tunnels under the surface, and that have since collapsed into voids.

The bottoms of the troughs are littered with circular depressions. While some of these are probably impact craters, most are likely collapse features. When a large number of small craters are in one location, they are often secondary craters that were formed by ejecta (material ejected from the surface) from another, larger impact. Such craters would be in clumps and often overlap. This type of distribution is not seen here; the depressions are concentrated on the trough floors, evidence of collapse.

Written by: Kelly Kolb  (5 December 2007)

This is a stereo pair with PSP_004899_1940.
Acquisition date
20 September 2007

Local Mars time

Latitude (centered)

Longitude (East)

Spacecraft altitude
263.9 km (164.0 miles)

Original image scale range
30.8 cm/pixel (with 1 x 1 binning) so objects ~92 cm across are resolved

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25 cm/pixel and North is up

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Solar incidence angle
46°, with the Sun about 44° above the horizon

Solar longitude
317.0°, Northern Winter

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North azimuth:  95°
Sub-solar azimuth:  321.0°
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