Space

September 28, 2012

NASA Mars rover finds old streambed on Martian surface

NASA’s Curiosity rover mission has found evidence a stream once ran vigorously across the area on Mars where the rover is driving. There is earlier evidence for the presence of water on Mars, but this evidence – images of rocks containing ancient streambed gravels – is the first of its kind.

Scientists are studying the images of stones cemented into a layer of conglomerate rock. The sizes and shapes of stones offer clues to the speed and distance of a long-ago stream’s flow.

“From the size of gravels it carried, we can interpret the water was moving about 3 feet per second, with a depth somewhere between ankle and hip deep,” said Curiosity science co-investigator William Dietrich of the University of California, Berkeley. “Plenty of papers have been written about channels on Mars with many different hypotheses about the flows in them. This is the first time we’re actually seeing water-transported gravel on Mars. This is a transition from speculation about the size of streambed material to direct observation of it.”

The finding site lies between the north rim of Gale Crater and the base of Mount Sharp, a mountain inside the crater. Earlier imaging of the region from Mars orbit allows for additional interpretation of the gravel-bearing conglomerate. The imagery shows an alluvial fan of material washed down from the rim, streaked by many apparent channels, sitting uphill of the new finds.

The rounded shape of some stones in the conglomerate indicates long-distance transport from above the rim, where a channel named Peace Vallis feeds into the alluvial fan. The abundance of channels in the fan between the rim and conglomerate suggests flows continued or repeated over a long time, not just once or for a few years.

The discovery comes from examining two outcrops, called “Hottah” and “Link” with the telephoto capability of Curiosity’s mast camera during the first 40 days after landing. Those observations followed up on earlier hints from another outcrop, which was exposed by thruster exhaust as Curiosity, the Mars Science Laboratory Project’s rover, touched down.

“Hottah looks like someone jack-hammered up a slab of city sidewalk, but it’s really a tilted block of an ancient streambed,” said Mars Science Laboratory Project Scientist John Grotzinger of the California Institute of Technology in Pasadena.

The gravels in conglomerates at both outcrops range in size from a grain of sand to a golf ball. Some are angular, but many are rounded.

“The shapes tell you they were transported and the sizes tell you they couldn’t be transported by wind. They were transported by water flow,” said Curiosity science co-investigator Rebecca Williams of the Planetary Science Institute in Tucson, Ariz.

The science team may use Curiosity to learn the elemental composition of the material, which holds the conglomerate together, revealing more characteristics of the wet environment that formed these deposits. The stones in the conglomerate provide a sampling from above the crater rim, so the team may also examine several of them to learn about broader regional geology.

The slope of Mount Sharp in Gale Crater remains the rover’s main destination. Clay and sulfate minerals detected there from orbit can be good preservers of carbon-based organic chemicals that are potential ingredients for life.

“A long-flowing stream can be a habitable environment,” said Grotzinger. “It is not our top choice as an environment for preservation of organics, though. We’re still going to Mount Sharp, but this is insurance that we have already found our first potentially habitable environment.”

During the two-year prime mission of the Mars Science Laboratory, researchers will use Curiosity’s 10 instruments to investigate whether areas in Gale Crater have ever offered environmental conditions favorable for microbial life.

 




All of this week's top headlines to your email every Friday.


 
 

 

Headlines December 22, 2014

News: Report: DOD bomb hunters pried into U.S. firms, citizens - During some of the bloodiest days of U.S. combat in Afghanistan and the roadside bomb threat there, the Pentagon’s Joint IED Defeat Organization “improperly collected” intelligence on U.S. citizens and corporations to try to stem the threat, a Pentagon Inspector General report has found.  ...
 
 

News Briefs December 22, 2014

U.K., Canadian military leaves to join Ebola fight Reservists and troops from Britain and Canada have left for Sierra Leone to help in the battle to contain the Ebola virus outbreak. British officials said Dec. 20 that 16 reservists and 100 regular military personnel left on a morning flight from the Brize Norton military airbase....
 
 
Boeing photograph

Boeing, Malaysia Airlines celebrate 100th 737 delivery

Boeing photograph Boeing and Malaysia Airlines celebrated the direct delivery of the airline’s 100th 737 aircraft at an event in Seattle. Shown here Aminuddin Zakaria, senior vice president, airline engineering group, Malaysi...
 

 

Navy helicopter crashes in Kuwait; all crewmembers ok

A U.S. Navy MH-60S helicopter assigned to Helicopter Sea Combat Squadron 26 (HSC 26) crashed at 11:22 a.m., EST, Dec.21, while on an overland training flight at Camp Buehring, Kuwait. All six personnel aboard the helicopter survived the crash and were transported to nearby medical facilities for evaluation. Three of the six crewmembers sustained minor...
 
 

AMC relocates KC-135 simulator

As Air Mobility Command fields the KC-46A Pegasus, displaced KC-135 Stratotanker pilot simulators will be relocated across the Total Force to maximize simulator access across the mobility enterprise. As a result, AMC, in coordination with the Air National Guard, recently identified four KC-135 pilot flight simulators and one KC-135 Boom Operator Weapons System Trainer to...
 
 

SpaceX completes first milestone for Commercial Crew Transportation System

NASA has approved the completion of SpaceX’s first milestone in the company’s path toward launching crews to the International Space Station from U.S. soil under a Commercial Crew Transportation Capability contract with the agency. During the Certification Baseline Review, SpaceX described its current design baseline including how the company plans to manufacture its Crew Dragon spacecraft...
 




0 Comments


Be the first to comment!


Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>