Reports Detail Rover Discoveries Of Wet Martian History

MARSDAILY

This high-resolution image captured by the Mars Exploration Rover Opportunity's panoramic camera highlights the puzzling rock outcropping that scientists are eagerly planning to investigate. Presently, Opportunity is on its lander facing northeast; the outcropping lies to the northwest. These layered rocks measure only 10 centimeters (4 inches) tall and are thought to be either volcanic ash deposits or sediments carried by water or wind. Data from the panoramic camera's near-infrared, blue and green filters were combined to create this approximate, true-color image. Image Credit: NASA/JPL/ Cornell.

Pasadena CA (JPL) Dec 03, 2004
The most dramatic findings so far from NASA's twin Mars rovers - telltale evidence for a wet and possibly habitable environment in the arid planet's past - passed rigorous scientific scrutiny for publication in a major research journal.

Eleven reports by 122 authors in Friday's issue of the journal Science present results from Opportunity's three-month prime mission, fleshing out headline discoveries revealed earlier.

Opportunity bounced to an airbag-cushioned landing on Jan. 24. It is exploring a region called Meridiani Planum, halfway around Mars from where its twin, Spirit, landed three weeks earlier.

Sedimentary rocks Opportunity examined, "clearly preserve a record of environmental conditions different from any on Mars today," report 50 rover-team scientists led by Dr. Steve Squyres of Cornell University, Ithaca, N.Y. and Dr. Ray Arvidson of Washington University, St. Louis, Mo.

"Liquid water was once intermittently present at the martian surface at Meridiani, and at times it saturated the subsurface. Because liquid water is a key prerequisite for life, we infer conditions at Meridiani may have been habitable for some period of time in martian history," according to Squyres, Arvidson and other co-authors.

"Formal review and publication this week of these amazing discoveries further strengthens the need for continued exploration by orbiters, surface robots, sample-return missions and human explorers. There are more exciting discoveries awaiting us on the red planet," said Dr. Michael Meyer, chief scientist for Mars exploration at NASA Headquarters, Washington.

Opportunity and Spirit have driven a combined 5.75 kilometers (3.57 miles), nearly five times their mission-success goal. They continue in good health after operating more than three times as long as the three-month prime missions for which they were designed.

NASA's rover team makes the resulting scientific discoveries available quickly to the public and the science community. One type of evidence that Meridiani was wet is the composition of rocks there.

The rocks have a high and variable ratio of bromine to chlorine; indicating "the past presence of large amounts of water," write Dr. Rudi Rieder and Dr. Ralf Gellert of Max-Planck-Institute for Chemistry, Mainz, Germany, and co-authors.

Their paper and another by Dr. Phil Christensen of Arizona State University, Tempe, and collaborators report an abundance of sulfur-rich minerals in the rocks, another clue to a watery past.

Clinching the case is identification of a hydrated iron-sulfate salt called jarosite in the rocks, as reported by Dr. Goestar Klingelhoefer of the University of Mainz, and Dr. Richard Morris of NASA's Johnson Space Center, Houston, and co-authors.

Structures within the rocks add more evidence according to Dr. Ken Herkenhoff of the U.S. Geological Survey, Flagstaff, Ariz., and co-authors. Plentiful cavities, about the size of shirt buttons, indicate crystals formed inside the rocks then dissolved.

Minerals carried by water formed peppercorn-size gray spheres, nicknamed "blueberries," that are embedded in the rocks. Certain angled patterns of fine layers in some rocks tell experts a flowing body of surface water shaped the sediments that became the rocks.

Several characteristics of the rocks suggest water came and went repeatedly, as it does in some shallow lakes in desert environments on Earth.

That fluctuation, plus the water's possible high acidity and saltiness, would have posed challenges to life, but not necessarily insurmountable ones, according to researchers.

If life ever did exist at Meridiani, the type of rocks found there could be good preservers of fossils, according to Squyres, Dr. John Grotzinger of the Massachusetts Institute of Technology, Cambridge, and co-authors.

MARSDAILY

Martian Water From A Stone

Moffett Field CA (SPX) Nov 16, 2004
Since the earliest planetary landers, much attention has been paid to the biological implications of returning samples back to Earth. The moon rocks led to the creation of NASA's Planetary Protection Office. But less attention has been paid to what happens if the rocks themselves change during their trip to Earth?

Thanks for being here; We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain. With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords. Our news coverage takes time and effort to publish 365 days a year. If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Contributor $5 Billed Once credit card or paypal		SpaceDaily Monthly Supporter $5 Billed Monthly paypal only

The content herein, unless otherwise known to be public domain, are Copyright 1995-2016 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement All images and articles appearing on Space Media Network have been edited or digitally altered in some way. Any requests to remove copyright material will be acted upon in a timely and appropriate manner. Any attempt to extort money from Space Media Network will be ignored and reported to Australian Law Enforcement Agencies as a potential case of financial fraud involving the use of a telephonic carriage device or postal service.