Media Information

 
 
 
Collection:
NASA Planetary Photo Journal Collection
Title:
Evros Vallis and Nearby Craters
Original Caption Released with Image:

Click on image for larger version

This HiRISE image (PSP_0 03273_1675) shows part of Evros Vallis, one of the Martian valley networks.

These more ancient valley networks may have been eroded by flowing water during a warmer, wetter period of Martian history. Many dunes are visibile along the valley floor, as well as throughout the scene and in a partially exhumed crater on the valley wall. There are multiple generations and orientations of dunes. Dune orientation reflects the dominant or prevailing wind direction. Multiple dune orientations indicate that this region has experienced different wind regimes.

An exhumed crater is one that likely formed a long time ago, was buried, and is now being re-exposed because the materials that originally covered it are being eroded away. The prominent crater on the valley wall as well as several other craters in this scene are thought to be partially exhumed.

The subim age (approximately 300 m across) shows a couple groups of secondary craters. Secondary craters are craters that form when ejecta from the primary crater hits the surface with enough energy to form another smaller crater. As seen in the subimage, secondary craters often form in clusters spatially, because ejecta thrown out of the primary crater impacts the surface near each other at approximately the same time.

Many potential secondary craters have have similar morphologies and have distinct, bright ejecta. This implies that these craters are relatively young and that their ejecta have yet to be covered by dust.

Observation Toolbox
Acquisition date: 4 April 2007
Local Mars time: 3:41 PM
Degrees latitude (centered): -12.6°
Degrees longitude (East): 13.3°
Range to target site: 264.3 km (165.2 miles)
Original image scale range: 26.4 cm/pixel (with 1 x 1 binning) so objects ~79 cm across are resolved
Map-projected scale: 25 cm/pixel and north is up
Map-projection: EQUIRECTANGULAR
Emission angle: 7.6°
Phase angle: 46.2°
Solar incidence angle: 54°, with the Sun about 36° above the horizon
Solar longitude: 215.3°, Northern Autumn

NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Reconnaissance Orbiter for NASA's Science Mission Directorate, Washington. Lockheed Martin Space Systems, Denver, is the prime contractor for the project and built the spacecraft. The High Resolution Imaging Science Experiment is operated by the University of Arizona, Tucson, and the instrument was built by Ball Aerospace and Technology Corp., Boulder, Colo.
Image Credit:
NASA/JPL/Univ. of Arizona
Produced By:
University of Arizona/HiRise-LPL
Mission:
Mars Reconnaissance Orbiter (MRO)
Spacecraft:
Mars Reconnaissance Orbiter (MRO)
Target Name:
Mars
Is a satellite of:
Sol (our sun)
Instrument:
HiRISE
Product Size:
2048 samples x 4047 lines
facet_what:
Sun
facet_what:
Crater
facet_what:
Mars
facet_what:
MRO
facet_what:
Mars Reconnaissance Orbiter (MRO)
facet_what:
High Resolution Imaging Science Experiment (HiRISE)
facet_where:
Jet Propulsion Laboratory
facet_where:
Denver
facet_where:
Mars
facet_where:
Arizona
facet_where:
California
facet_where:
Washington
facet_where:
The Valley
facet_where:
Jet Propulsion Laboratory (JPL)
facet_when:
April 2007
facet_when_year:
2007
Image #:
PIA09684
UID:
SPD-PHOTJ-PIA09684
orignial url:

Evros Vallis and Nearby Craters