01.06.2017 Earth and Its Moon, as Seen From Mars
11.15.2016 Schiaparelli Impact Site on Mars, Stereo
11.03.2016 Schiaparelli Impact Site on Mars, in Color
03.30.2016 Erisa Hines
03.30.2016 Buzz Aldrin
03.21.2016 For a Decade Orbiting Mars: One Recent View
03.09.2016 For a Decade Orbiting Mars: One Recent View
03.09.2016 Mars Reconnaissance Orbiter By the Numbers
03.01.2016 MRO sees Frosty Spring Slopes
02.12.2016 Women in Science
02.10.2016 Wind at Work
11.16.2015 Change Observed in Martian Sand Dune
10.05.2015 'The Martian' Story's Ares 4 Landing Site
10.05.2015 The Ares 3 Landing Site (Figure A)
09.30.2015 Avalanche Ho!
06.29.2015 Mars Exploration Zone Layout Considerations
06.17.2015 Active High-Latitude Dune Gullies
06.03.2015 Crisp Crater in Sirenum Fossae
05.20.2015 Sedimentary Rock Layers on a Crater Floor
05.20.2015 Honey, I Shrunk the Mesas
05.11.2015 Icy Wonderland
05.04.2015 Diverse Orbits Around Mars
03.27.2015 South Pole Spiders
03.27.2015 A Smile a Day....
03.25.2015 Pitted Landforms in Southern Hellas Planitia
03.12.2015 Curiosity Heading Away from 'Pahrump Hills'
02.18.2015 Lava Flow Near the Base of Olympus Mons
02.09.2015 Yardangs in Arsinoes Chaos, Mars
02.04.2015 Curiosity Rover at 'Pahrump Hills'
01.22.2015 Frost on Crater Slope
01.16.2015 Components of Beagle 2 Flight System on Mars
12.03.2014 An Enigmatic Feature in Athabasca Lava Flows
12.02.2014 NASA's Journey to Mars
11.07.2014 Mars Orbiter Sizes Up Passing Comet
10.19.2014 Siding Spring Mars Spacecraft
Dark Rimless Pits in the Tharsis RegionTwo dark, rimless pits are located to the northwest of Ascraeus Mons in the Tharsis volcanic region of Mars. These pits are approximately 180 meters (591 feet) and 310 meters (1,017 feet) in diameter. They are situated in the midst of a wispy, dark, boomerang-shaped deposit.
The pits are aligned with what appear to be larger, degraded depressions. The wispy deposit may consist of dark material blown out of the pits or from some other source.
Figure A and Figure B are close-ups of the two pits. These images have been highly processed to reveal the surface details within each pit. The eastern and smaller of the two pits (A) contains boulders and sediment along its walls and brighter, wind-shaped dune sediments on its floor. The larger, western pit (B) contains sediment and boulders with faint dune-like patterns visible on the deepest part of the floor. Both pits have steep eastern walls and more gently sloped western walls that transition gradually into the pit floor. Steep, resistant ledges containing boulders that overhang and obscure the pit floors form the eastern walls.
Careful study of the walls and floors of the pits, as well as of the surrounding terrain, will help unravel the complicated series of processes that must have been responsible for their formation and subsequent modification.
This image covers an area about 6 kilometers (4 miles) wide. It is one product from a Nov. 1, 2010, HiRISE observation catalogued as ESP_019997_1975, of an area centered at 17.2 degrees north latitude, 247.6 degrees east longitude. Other image products from this observation are available at http://hirise.lpl.arizona.edu/ESP_019997_1975.
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, 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 & Technologies Corp., Boulder, Colo.
Image Credit: NASA/JPL-Caltech/University of Arizona