[meteorite-list] NASA Rover's First Soil Studies Help Fingerprint Martian Minerals

[Ron Baalke]

Oct. 30, 2012

Dwayne Brown 
Headquarters, Washington                               
202-358-1726 
dwayne.c.brown at nasa.gov 

Guy Webster 
Jet Propulsion Laboratory, Pasadena, Calif. 
818-354-6278 
guy.webster at jpl.nasa.gov 

Rachel Hoover 
Ames Research Center, Moffet Field, Calif. 
650-604-4789 
rachel.hoover at nasa.gov 

RELEASE: 12-383

NASA ROVER'S FIRST SOIL STUDIES HELP FINGERPRINT MARTIAN MINERALS

PASADENA, Calif. -- NASA's Mars rover Curiosity has completed initial 
experiments showing the mineralogy of Martian soil is similar to 
weathered basaltic soils of volcanic origin in Hawaii. 

The minerals were identified in the first sample of Martian soil 
ingested recently by the rover. Curiosity used its Chemistry and 
Mineralogy instrument (CheMin) to obtain the results, which are 
filling gaps and adding confidence to earlier estimates of the 
mineralogical makeup of the dust and fine soil widespread on the Red 
Planet. 

"We had many previous inferences and discussions about the mineralogy 
of Martian soil," said David Blake of NASA Ames Research Center in 
Moffett Field, Calif., who is the principal investigator for CheMin. 
"Our quantitative results provide refined and in some cases new 
identifications of the minerals in this first X-ray diffraction 
analysis on Mars." 

The identification of minerals in rocks and soil is crucial for the 
mission's goal to assess past environmental conditions. Each mineral 
records the conditions under which it formed. The chemical 
composition of a rock provides only ambiguous mineralogical 
information, as in the textbook example of the minerals diamond and 
graphite, which have the same chemical composition, but strikingly 
different structures and properties. 

CheMin uses X-ray diffraction, the standard practice for geologists on 
Earth using much larger laboratory instruments. This method provides 
more accurate identifications of minerals than any method previously 
used on Mars. X-ray diffraction reads minerals' internal structure by 
recording how their crystals distinctively interact with X-rays. 
Innovations from Ames led to an X-ray diffraction instrument compact 
enough to fit inside the rover. 

These NASA technological advances have resulted in other applications 
on Earth, including compact and portable X-ray diffraction equipment 
for oil and gas exploration, analysis of archaeological objects and 
screening of counterfeit pharmaceuticals, among other uses. 

"Our team is elated with these first results from our instrument," 
said Blake. "They heighten our anticipation for future CheMin 
analyses in the months and miles ahead for Curiosity." 

The specific sample for CheMin's first analysis was soil Curiosity 
scooped up at a patch of dust and sand that the team named Rocknest. 
The sample was processed through a sieve to exclude particles larger 
than 0.006 inch (150 micrometers), roughly the width of a human hair. 
The sample has at least two components: dust distributed globally in 
dust storms and fine sand originating more locally. Unlike 
conglomerate rocks Curiosity investigated a few weeks ago, which are 
several billion years old and indicative of flowing water, the soil 
material CheMin has analyzed is more representative of modern 
processes on Mars. 

"Much of Mars is covered with dust, and we had an incomplete 
understanding of its mineralogy," said David Bish, CheMin 
co-investigator with Indiana University in Bloomington. "We now know 
it is mineralogically similar to basaltic material, with significant 
amounts of feldspar, pyroxene and olivine, which was not unexpected. 
Roughly half the soil is non-crystalline material, such as volcanic 
glass or products from weathering of the glass." 

Bish said, "So far, the materials Curiosity has analyzed are 
consistent with our initial ideas of the deposits in Gale Crater 
recording a transition through time from a wet to dry environment. 
The ancient rocks, such as the conglomerates, suggest flowing water, 
while the minerals in the younger soil are consistent with limited 
interaction with water." 

During the two-year prime mission of the Mars Science Laboratory 
Project, researchers are using Curiosity's 10 instruments to 
investigate whether areas in Gale Crater ever offered environmental 
conditions favorable for microbial life. NASA's Jet Propulsion 
Laboratory, Pasadena, Calif., manages the project for NASA's Science 
Mission Directorate, Washington, and built Curiosity and CheMin. 

For more information about Curiosity and its mission, visit: 

http://www.nasa.gov/msl 

For more information about a commercial application of the CheMin 
technology, visit: 

http://blogs.getty.edu/iris/mars-rover-technology-helps-unlock-art-mysteries/ 

You can follow the mission on Facebook and Twitter at: 

http://www.facebook.com/marscuriosity 

and 

http://www.twitter.com/marscuriosity 
	
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