Photos
Article

This colorful scene is situated in the Noctis Labyrinthus region of Mars, perched high on the Tharsis rise in the upper reaches of the Valles Marineris canyon system.

 

Targeting the bright rimmed bedrock knobs, the image also captures the interaction of two distinct types of windblown sediments. Surrounding the bedrock knobs is a network of pale reddish ridges with a complex interlinked morphology. These pale ridges resemble the simpler “transverse aeolian ridges” (called TARs) that are common in the equatorial regions of Mars.

 

The TARs are still poorly understood, and are variously ascribed to dunes produced by reversing winds, coarse grained ripples, or indurated dust deposits. HiRISE observations of TARs have so far shown that these bedforms are stable over time, suggesting either that they form slowly over much longer time scales than the duration of MRO's mission, or that they formed in the past during periods of very different atmospheric conditions than the present.

 

Dark sand dunes comprise the second type of windblown sediment visible in this image. The dark sand dune seen just below the center of the cutout displays features that are common to active sand dunes observed by HiRISE elsewhere on Mars, including sets of small ripples crisscrossing the top of the dune. In many cases, it is the motion of these smaller ripples that drives the advance of Martian sand dunes. The dark dunes are made up of grains composed of iron-rich minerals derived from volcanic rocks on Mars, unlike the pale quartz-rich dunes typical of Earth.

 

This image clearly shows the dark sand situated on top of the pale TAR network, indicating that the sand dunes are younger than the TARs. Moreover, the fresh appearance of the sand dunes suggest that they are currently active, and may help shape the unusual TAR morphology by sandblasting the TARs in the present day environment.

 

The original image was acquired on Aug. 31, 2013, by the HiRISE (High Resolution Imaging Science Experiment) instrument aboard NASA's Mars Reconnaissance Orbiter (MRO). HiRISE is operated by the University of Arizona, Tucson.

 

Original Source: http://www.nasa.gov/content/two-generations-of-windblown-sediments-on-mars/#.UkGr9YakpWU

External Video
You need Flash player 8+ and JavaScript enabled to view this video.

Comments
Order by: 
Per page: 
 
  • There are no comments yet
The Social Network Buzz - Comment using your Facebook, AOL, Hotmail or Yahoo! account
Info
Administrator
The Black Vault Owner/Operator
09.24.2013 (206 days ago)
Main Space
618 Views
0 Subscribers
All News by Administrator
Share This Article
Rate
0 votes
Related News
Using NASA's Kepler Space Telescope, astronomers have discovered the first Earth-size planet orbiting a star in the "habitable zone"
Main Space
21 hours ago · From Administrator
Pivoting planets that lean one way and then change orientation within a short geological time period might be surprisingly habitable
Main Space
2 days ago · From Administrator
Life took root more than four billion years ago on our nascent Earth, a wetter and harsher place than now, bathed in sizzling ultraviolet rays.
Main Space
3 days ago · From Administrator
NASA's Cassini spacecraft has documented the formation of a small icy object within the rings of Saturn that may be a new moon
Main Space
4 days ago · From Administrator
The public will have the opportunity to view and learn more about the Tuesday, April 15 total lunar eclipse on NASA television, the agency’s website, and social media.
Main Space
4 days ago · From Administrator
Two Generations of Windblown Sediments on Mars