Opportunity rover finds mineral vein deposited by water

December 8, 2011
This color view of a mineral vein called "Homestake" comes from the panoramic camera (Pancam) on NASA's Mars Exploration Rover Opportunity. The vein is about the width of a thumb and about 18 inches (45 centimeters) long. Credit: NASA/JPL-Caltech/Cornell/ASU

(PhysOrg.com) -- NASA's Mars Exploration Rover Opportunity has found bright veins of a mineral, apparently gypsum, deposited by water. Analysis of the vein will help improve understanding of the history of wet environments on Mars.

"This tells a slam-dunk story that water flowed through underground fractures in the rock," said Steve Squyres of Cornell University, principal investigator for Opportunity. "This stuff is a fairly pure chemical deposit that formed in place right where we see it. That can't be said for other seen on or for other water-related minerals Opportunity has found. It's not uncommon on Earth, but on Mars, it's the kind of thing that makes jump out of their chairs."

The latest findings by Opportunity were presented Wednesday at the American Geophysical Union's conference in San Francisco.

The vein examined most closely by Opportunity is about the width of a human thumb (0.4 to 0.8 inch), 16 to 20 inches long, and protrudes slightly higher than the bedrock on either side of it. Observations by the durable rover reveal this vein and others like it within an apron surrounding a segment of the rim of Endeavour Crater. None like it were seen in the 20 miles (33 kilometers) of crater-pocked plains that Opportunity explored for 90 months before it reached Endeavour, nor in the higher ground of the rim.

Last month, researchers used the Microscopic Imager and X-ray Spectrometer on the rover's arm and multiple filters of the on the rover's mast to examine the vein, which is informally named "Homestake." The spectrometer identified plentiful calcium and sulfur, in a ratio pointing to relatively pure calcium sulfate.

Calcium sulfate can exist in many forms, varying by how much water is bound into the minerals' . The multi-filter data from the camera suggest gypsum, a hydrated calcium sulfate. On Earth, gypsum is used for making drywall and plaster of Paris.

Observations from orbit have detected gypsum on Mars previously. A dune field of windblown gypsum on far northern Mars resembles the glistening gypsum dunes in White Sands National Monument in New Mexico.

"It is a mystery where the gypsum sand on northern Mars comes from," said Opportunity science-team member Benton Clark of the Space Science Institute in Boulder, Colo. "At Homestake, we see the mineral right where it formed. It will be important to see if there are deposits like this in other areas of Mars."

The Homestake deposit, whether gypsum or another form of calcium sulfate, likely formed from water dissolving calcium out of volcanic rocks. The minerals combined with sulfur either leached from the rocks or introduced as volcanic gas, and was deposited as calcium sulfate into an underground fracture that later became exposed at the surface.

Throughout Opportunity's long traverse across Mars' Meridiani plain, the rover has driven over bedrock composed of magnesium, iron and calcium sulfate minerals that also indicate a wet environment billions of years ago. The highly concentrated calcium sulfate at Homestake could have been produced in conditions more neutral than the harshly acidic conditions indicated by the other sulfate deposits observed by Opportunity.

"It could have formed in a different type of water environment, one more hospitable for a larger variety of living organisms," Clark said.

Homestake and similar-looking veins appear in a zone where the sulfate-rich sedimentary bedrock of the plains meets older, volcanic bedrock exposed at the rim of Endeavour. That location may offer a clue about their origin.

"We want to understand why these veins are in the apron but not out on the plains," said the mission's deputy principal investigator, Ray Arvidson, of Washington University in St. Louis. "The answer may be that rising groundwater coming from the ancient crust moved through material adjacent to Cape York and deposited gypsum, because this material would be relatively insoluble compared with either magnesium or iron sulfates."

Opportunity and its rover twin, Spirit, completed their three-month prime missions on Mars in April 2004. Both rovers continued for years of extended missions and made important discoveries about wet environments on ancient Mars that may have been favorable for supporting microbial life. Spirit stopped communicating in 2010. Opportunity continues exploring, currently heading to a sun-facing slope on the northern end of the Endeavour rim fragment called "Cape York" to keep its solar panels at a favorable angle during the mission's fifth Martian winter.

NASA launched the next-generation Mars rover, the car-sized Curiosity, on Nov. 26. It is slated for arrival at the planet's Gale Crater in August 2012.

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1 / 5 (1) Dec 08, 2011
I have to wonder why these images are so red, when if you were standing on Mars you would see a bluish sky and a reddish Utah like landscape.

I'm sure it's not intentional that NASA is misrepresenting how Mars really looks if you were standing on it's surface.

1 / 5 (5) Dec 08, 2011
NASA uses false colorization on the raw images they receive from cameras on the rovers and aboard the orbiters. They colorize the images before releasing them to the general public via the media and on NASA websites and other science sites. They have been accused by many research groups of masking various features of Mars through gray filters as well as colors that can hide natural and normal artifacts that may be anomalous.
If one were able to view the raw images before changes are made to them, one might find that the raw images are quite different from the finished images.
Several former NASA employees have testified that NASA routinely airbrushes out those features of Mars that they don't want outsiders to see. Others have said also that military and NASA pictures of UFOs above Earth are also airbrushed out.
It's not a conspiracy done by NASA at all. It's more of a "protective" measure instead.
2 / 5 (68) Dec 08, 2011
Here's the link to Pirouette's "group" (he and his girlfriend). http://www.marscr...pot.com/
Closeup photos of the helmeted male and his female companion. They seem to be about to take flight.

The three photos above show a closeup of the cave-like structure which does NOT appear to be natural. Rather, it seems, to me, that it is artificial and may be housing for these gigantic humanoids.

These four photos above show the two females. Note the shadow cast by the headdress or cap that the female below is wearing.

This giant appears to be trying to climb over the broken stone idol to visit with the "girls" down below in the "grotto". His face is surrounded by some type of head covering and he may be wearing something to keep him warm. . . .a parka, maybe?

One has to wonder what could possibly have motivated the NASA scientists to destroy the glassy covering on this rock, and thereby probably killing the creatures that lived inside.

Pirouette is crazy.
1 / 5 (5) Dec 08, 2011

The object in the picture is obviously a sickle handle.

I believe the head of the sickle was cast here: http://www.physor...lem.html

Obviously the Anunnaki were manipulating the ancient Jews into creating agricultural equipment for them.

Why isn't NASA searching for Martian farms? They are obviously there but probably hidden by the color filters NASA uses.

We should be searching for monochromatic, maybe semitransparent Martian farms. The farms should be very easy to spot from orbit, even more so than the giant humanoid creatures visible from Earth with simple binoculars.

The last time I went to walmart there were no binoculars and they said they had sold out but it looked like they were removed from the shelves. Why is NASA preventing walmart from selling binoculars?
Dec 09, 2011
This comment has been removed by a moderator.
5 / 5 (3) Dec 09, 2011
"Why is NASA preventing walmart from selling binoculars?" I LOLed.

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