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.


 
 

 
ATK

ATK completes installation of world’s largest solid rocket motor for ground test

ATK The first qualification motor for NASA’s Space Launch Systems booster is installed in ATK’s test stand in Utah – ready for a March 11 static-fire test. NASA and ATK have completed installing the first Spac...
 
 
ULA photograph

Third Lockheed Martin-built MUOS satellite launched, responding to commands

ULA photograph The U.S. Air Force’s 45th Space Wing successfully launched the third Mobile User Objective System satellite, built by Lockheed Martin, for the U.S. Navy at 8:04 p.m. Jan. 20, 2015, from Launch Complex 41 at...
 
 
ULA photograph

ULA successfully launches Navy’s Mobile User Objective System-3

ULA photograph The U.S. Air Force’s 45th Space Wing successfully launched the third Mobile User Objective System (MUOS) satellite, built by Lockheed Martin, for the U.S. Navy at 8:04 p.m. Jan. 20, 2015, from Launch Comple...
 

 

Aerojet Rocketdyne Propulsion supports launch, flight of third MUOS satellite

Aerojet Rocketdyne played a critical role in successfully placing the third of five planned Mobile User Objective System (MUOS-3) satellites, designed and built by Lockheed Martin, into orbit for the U.S. Navy. The mission was launched from Cape Canaveral Air Force Station in Florida aboard a United Launch Alliance Atlas V rocket, with five Aerojet...
 
 
LM-MUOS-satellite

U.S. Navy poised to Launch Lockheed Martin-built MUOS-3 satellite

The U.S. Navy and Lockheed Martin are ready to launch the third Mobile User Objective System satellite, MUOS-3, from Cape Canaveral Air Force Station, Fla., Jan. 20 aboard a United Launch Alliance Atlas V rocket. The launch win...
 
 

NASA, NOAA find 2014 warmest year in modern record

https://www.youtube.com/embed/-ilg75uJZZU?enablejsapi=1&rel=0 The year 2014 ranks as Earth’s warmest since 1880, according to two separate analyses by NASA and National Oceanic and Atmospheric Administration scientists. The 10 warmest years in the instrumental record, with the exception of 1998, have now occurred since 2000. This trend continues a long-term warming of the planet, acc...
 




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>