There is 1 message totalling 66 lines in this issue

Topics of the day:

1. NASA ROVER FINDS CLUE TO MARS' PAST AND ENVIRONMENT FOR LIFE

Date: Thu, 3 Jun 2010 15:45:07 -0500 From: info@JSC NASA GOV Subject: NASA ROVER FINDS CLUE TO MARS' PAST AND ENVIRONMENT FOR LIFE

June 3, 2010

William Jeffs Johnson Space Center, Houston 281-483-5111

Dwayne Brown
Headquarters, Washington
202-358-1726

Guy Webster Jet Propulsion Laboratory, Pasadena, Calif 818-354-6278

Report #H10-131

NASA ROVER FINDS CLUE TO MARS' PAST AND ENVIRONMENT FOR LIFE

PASADENA, Calif -- Rocks examined by NASA's Spirit Mars Rover hold evidence of a wet, non-acidic ancient environment that may have been favorable for life Confirming this mineral clue took four years of analysis by several scientists

An outcrop that Spirit examined in late 2005 revealed high concentrations of carbonate, which originates in wet, near-neutral conditions, but dissolves in acid The ancient water indicated by this find was not acidic

NASA's rovers have found other evidence of formerly wet Martian environments However the data for those environments indicate conditions that may have been acidic In other cases, the conditions were definitely acidic, and therefore less favorable as habitats for life

Laboratory tests helped confirm the carbonate identification The findings were published online Thursday, June 3 by the journal Science

"This is one of the most significant findings by the rovers," said Steve Squyres of Cornell University in Ithaca, N Y Squyres is principal investigator for the Mars twin rovers, Spirit and Opportunity, and a co-author of the new report "A substantial carbonate deposit in a Mars outcrop tells us that conditions that could have been quite favorable for life were present at one time in that place "

Spirit inspected rock outcrops, including one scientist called Comanche, along the rover's route from the top of Husband Hill to the vicinity of the Home Plate plateau which Spirit has studied since 2006 Magnesium iron carbonate makes up about one-fourth of the measured volume in Comanche That is a tenfold higher concentration than any previously identified for carbonate in a Martian rock

"We used detective work combining results from three spectrometers to lock this down," said Dick Morris, lead author of the report and a member of a rover science team at NASA's Johnson Space Center in Houston "The instruments gave us multiple, interlocking ways of confirming the magnesium iron carbonate, with a good handle on how much there is "

Massive carbonate deposits on Mars have been sought for years without much success Numerous channels apparently carved by flows of liquid water on ancient Mars suggest the planet was formerly warmer, thanks to greenhouse warming from a thicker atmosphere than exists now The ancient, dense Martian atmosphere was probably rich in carbon dioxide, because that gas makes up nearly all the modern, very thin atmosphere

It is important to determine where most of the carbon dioxide went Some theorize it departed to space Others hypothesize that it left the atmosphere by the mixing of carbon dioxide with water under conditions that led to forming carbonate minerals That possibility, plus finding small amounts of carbonate in meteorites that originated from Mars, led to expectations in the 1990s that carbonate would be abundant on Mars However, mineral-mapping spectrometers on orbiters since then have found evidence of localized carbonate deposits in only one area, plus small amounts distributed globally in Martian dust

Morris suspected iron-bearing carbonate at Comanche years ago from inspection of the rock with Spirit's Moessbauer Spectrometer, which provides information about iron-containing minerals Confirming evidence from other instruments emerged slowly The instrument with the best capability for detecting carbonates, the Miniature Thermal Emission Spectrometer, had its mirror contaminated with dust earlier in 2005, during a wind event that also cleaned Spirit's solar panels

"It was like looking through dirty glasses," said Steve Ruff of Arizona State University in Tempe, Ariz , another co-author of the report "We could tell there was something very different about Comanche compared with other outcrops we had seen, but we couldn't tell what it was until we developed a correction method to account for the dust on the mirror "

Spirit's Alpha Particle X-ray Spectrometer instrument detected a high concentration of light elements, a group including carbon and oxygen, that helped quantify the carbonate content

The rovers landed on Mars in January 2004 for missions originally planned to last three months Spirit has been out of communication since March 22 and is in a low-power hibernation status during Martian winter Opportunity is making steady progress toward a large crater, Endeavour, which is about seven miles away

NASA's Jet Propulsion Laboratory, Pasadena, manages the Mars Exploration Rovers for the agency's Science Mission Directorate in Washington For more information about the rovers, visit:

http://www nasa gov/rovers

#

NASA Johnson Space Center Mission Status Reports and other information are available automatically by sending an Internet electronic mail message to listserv@listserver jsc nasa gov In the body of the message (not the subject line) users should type "subscribe hsfnews" (no quotes) This will add the e-mail address that sent the subscribe message to the news release distribution list The system will reply with a confirmation via e-mail of each subscription Once you have subscribed you will receive future news releases via e-mail To unsubscribe, send an e-mail to listserv@listserver jsc nasa gov with the following command in the body of your e-mail message: "unsubscribe hsfnews" (no quotes) or from another account, besides the account used to subscribe: "unsubscribe hsfnews youremail@yourdomain com" (no quotes)

End of HSFNEWS Digest - 3 Jun 2010 to 4 Jun 2010 (#2010-74)

The following information is a reminder of your current mailing list subscription:

You are subscribed to the following list: [list_name]

using the following email: example@example.com

You may automatically unsubscribe from this list at any time by visiting the following URL:

https://aus-city com/cgi-bin/dada/mail cgi/u/NASA_REPORTS/example/example com/

If the above URL is inoperable, make sure that you have copied the entire address Some mail readers will wrap a long URL and thus break this automatic unsubscribe mechanism

You may also change your subscription by visiting this list's main screen:

<[program_url]/list/[list]>

If you're still having trouble, please contact the list owner at:

<mailto:[list_owner_email]>

The following physical address is associated with this mailing list:

[physical_address]