[meteorite-list] From Earth to Gale: Curiosity Aims for Martian Dry Lake Bed (MSL)

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Mon, 21 Nov 2011 16:38:17 -0800 (PST)
Message-ID: <201111220038.pAM0cHXJ000149_at_zagami.jpl.nasa.gov>

http://www.spaceflightnow.com/atlas/av028/111121gale/index.html

>From Earth to Gale: Curiosity aims for Martian dry lake bed
BY STEPHEN CLARK
SPACEFLIGHT NOW
November 21, 2011

The Curiosity rover is heading for a potential Martian dry lake bed the
size of Los Angeles adorned with ragged rock formations and a colossal
three-mile-high mountain.

Relying on a new descent system capable of pinpoint landings, the robot
will touch down Aug. 6, 2012, and drive uphill to analyze layers of clay
minerals that likely formed in the presence of abundant water.

"It will be a lot like areas in the Southwest [United States], places
like Monument Valley where we'll see these big cliffs with the rover
going between them," said Dawn Sumner, a geologist at the University of
California, Davis.

The 96-mile-wide Gale crater is marked with clays and sulfates at the
base of a 15,000-foot-tall mountain. If the mission lasts long enough,
Curiosity could climb the mound and study a range of minerals from long
ago.

"In one location, we can drive the rover through all these successive
different environments and sample these different periods in Martian
history," said John Grotzinger, the chief researcher for the Curiosity
rover at NASA's Jet Propulsion Laboratory in Pasadena, Calif.

Curiosty will take a set of stereo eyes, a sensor-laden robotic arm with
a scoop, and instruments to smell and taste soil in search of organic
molecules, the building blocks of life. The rover even carries a
microscope and a laser to zap rocks from several feet away.

Liftoff is scheduled for Saturday aboard an Atlas 5 rocket launched from
Cape Canaveral, Fla.

After considering 60 landing site candidates, scientists recommended
Gale crater as Curiosity's destination because it offered the widest
array of geologic research opportunities, giving the rover a window into
a large period of Martian history.

"There was a preference for Gale in that it's not a one-trick pony,"
said Michael Meyer, the lead scientist for NASA's Mars programs. "There
are several different environmental settings that can be explored, any
one of which might have the possibility of [holding] organic compounds."

The exploration of scenic Gale crater will also return thousands of
images from Curiosity's cameras.

Positioned just south of the Martian equator, the crater's central peak
is taller than any mountain in the continental United States.

After touching down on relatively flat terrain a few miles from the base
of the mound, Curiosity will drive south toward the peak and begin to
climb thousands of feet up its flank, pausing to examine clay and
sulfate salt minerals along the way, Grotzinger said.

Dried-up stream channels along the edge of the mound will allow access
up the mountain.

Curiosity's mission is supposed to last two years after landing, but
scientists are hopeful the rover will continue the climb up Gale's lofty
mountain for years more. Scientists say the most attractive scientific
targets are near the base of the central mountain, ensuring the rover
will produce quality results early in the mission.

The rover's mobility system has the ability to climb a 20-degree
incline. It's designed to drive at least 12 miles, according to Michael
Watkins, an MSL project engineer at JPL.

"Geologists like climbing up cliffs, and we get to go to those places
with this rover for the first time on Mars," Sumner said.

As the rover ascends the mountain, it will encounter rocks and soil left
behind as waters receded when Mars transitioned from a warm, wet planet
into the cold and desolate world known today.

Curiosity's analysis of clays and sulfates will tell scientists how much
water was once present at Gale, the characteristics of the water and how
it evaporated, according to Sumner.

"What we've learned is if you start at the bottom of the layers and you
work your way to the top, it's like reading a novel," Grotzinger said.
"And we think Gale is going to be a great novel."

Curiosity is not designed to directly detect life or find a fossil. It
would have to be "extremely lucky" to find ironclad evidence of life,
Meyer said.

But the clay minerals at Gale crater could hold rich deposits of organic
compounds and could point scientists closer toward their holy grail of
solving the Martian life mystery.

Curiosity's robot arm will dump soil into a sample analysis instrument
on the rover's main deck, where an oven and solvents will release
chemicals to be observed with laser and mass spectrometers and a gas
chromatograph. The high-tech device will sense and characterize
carbon-based molecules.

If Curiosity can find elusive carbon-based organic material inside
Gale's rocks, scientists will obtain evidence that the ingredients for
life were once plentiful on Mars.

NASA selected Gale from four finalists scattered across the Red Planet's
surface. Science return and safety were the two primary decision drivers.

Using high-resolution imagery from a sharp-eyed camera on NASA's Mars
Reconnaissance Orbiter, the landing site selection committee mapped
hazards and plotted driving paths for the rover at each of the four
finalist locations.

Spectrometers on orbiting satellites at Mars indicated Gale had the
widest variety of environments of all the sites, harboring both
relatively fresh and ancient material inside the crater, which
scientists believe is about 3 billion years old.
Received on Mon 21 Nov 2011 07:38:17 PM PST