Strewn boulders and rippled sand lie on the floors of two shadowy, steep-walled pits. Mounds in another region appear to be mud volcanoes, which may have brought fine-grained material to the surface from deep underground. In the Tharsis volcanic region, the intersection of a lava flow with a trough caused by ground collapse allows seeing whether the flow happened before or after the collapse.
These and thousands of other images from HiRISE observations between Oct. 1 and Nov. 1, 2010, are now available on NASA's Planetary Data System (http://pds.jpl.nasa.gov/) and the camera team's website (http://hirise.lpl.arizona.edu).
The camera is one of six instruments on NASA's Mars Reconnaissance Orbiter, which reached Mars in 2006. It has made more than 17,000 observations. Each observation covers an area of several square miles on Mars and reveals details as small as desks.
For more information about the Mars Reconnaissance Orbiter mission, see http://mars.jpl.nasa.gov/mro/.
Guy Webster (818) 354-6278
Jet Propulsion Laboratory, Pasadena, Calif.
- Sand Ripples Inside a Rimless Martian Pit (Stretched)
- Boulders Inside a Rimless Martian Pit (Stretched)
- Dark Rimless Pits in the Tharsis Region
- Graben Cutting Lava Flow in Tharsis
- Proposed Future Mars Landing Site: Acidalia Planitia Mud Volcanoes