The one thing becoming abundantly clear is that plenty of water
exists on Mars. What is lacking is geological activity that could be
described as tectonic. The bulk of the water is deep and possibly
the only driver is slow evaporation or sublimation. Even a short
volcanic cycle could create the surface we see in terms of water
caused features.
That is the key achievement of this multi year mission. Now we need
to figure out how to exploit such water to support an actual base.
Actually getting much further along will surely need boots on the
ground and that must surely wait for a much later day and rather
different technology than reaction engines.
Paydirt at
8-Year-Old Mars Rover's 'New Landing Site'
ScienceDaily (May 3,
2012) — A report in the May 4 edition of the
journal Science details discoveries Opportunity made in its
first four months at the rim of Endeavour Crater, including key
findings reported at a geophysics conference in late 2011.
Opportunity completed
its original three-month mission on Mars eight years ago. It reached
Endeavour last summer, three years after the rover's science team
chose Endeavour as a long-term destination. This crater is about 4
billion years old and 14 miles (22 kilometers) in diameter.
The impact that
excavated the crater left a jumble of fused-together rock fragments
around the rim. In a chunk brought to the surface by a later, much
smaller impact into the rim, Opportunity found evidence that the
original impact released heated, underground water that deposited
zinc in that rock. Later after the impact, cool water flowed through
cracks in the ground near the edge of the crater and deposited veins
of the mineral gypsum.
"These bright
mineral veins are different from anything seen previously on Mars,
and they tell a clear story of water flowing through cracks in the
rocks," said Steve Squyres of Cornell University, Ithaca,
N.Y. He is the principal investigator for Opportunity and lead author
of the new report by 27 researchers. "From landing until just
before reaching the Endeavour rim, Opportunity was driving over
sandstone made of sulfate grains that had been deposited by water and
later blown around by the wind. These gypsum veins tell us about
water that flowed through the rocks at this exact spot. It's the
strongest evidence for water that we've ever seen with Opportunity."
For the past four
months, the solar-powered rover has been working at one outcrop on
the Endeavour rim, called Greeley Haven. Reduced daylight during the
Martian winter, and accumulated dust on the rover's solar array, have
kept energy too low for driving. "The days are now growing
longer, and the sun is moving higher in the sky at Endeavour Crater.
We expect Opportunity to resume driving in the next two months and
continue exploring other parts of the crater's rim," said Mars
Exploration Rover Project Manager John Callas of NASA's Jet
Propulsion Laboratory, Pasadena, Calif.
Researchers hope to
get Opportunity to one of the deposits of clay minerals that have
been detected in Endeavour's rim by observations from orbit. These
minerals could be evidence of a non-acidic wet phase of the region's
environmental history.
"Exploring
Endeavour Crater is like having a new landing site," said JPL's
Timothy Parker, a co-author of the new report. "That's not just
because of the difference in the geology here compared to what we saw
during most of the first eight years, but also because there's a
whole vista before us inviting much more exploration."
Opportunity and its
rover twin, Spirit, completed their three-month prime missions on
Mars in April 2004. Both rovers continued for years of bonus,
extended missions. Both have made important discoveries about wet
environments on ancient Mars that may have been favorable for
supporting microbial life. Spirit stopped communicating in 2010.
NASA launched the
next-generation Mars rover, car-size Curiosity of the Mars Science
Laboratory mission, on Nov. 26 for arrival at Mars' Gale Crater in
August 2012.
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