[meteorite-list] NASA's Mars Curiosity Rover Marks First Martian Year with Mission Successes

[Ron Baalke]

June 23, 2014
     
NASA's Mars Curiosity Rover Marks First Martian Year with Mission Successes

NASA's Mars Curiosity rover will complete a Martian year -- 687 Earth days 
-- on June 24, having accomplished the mission's main goal of determining 
whether Mars once offered environmental conditions favorable for microbial 
life.

One of Curiosity's first major findings after landing on the Red Planet in 
August 2012 was an ancient riverbed at its landing site. Nearby, at an area 
known as Yellowknife Bay, the mission met its main goal of determining 
whether the Martian Gale Crater ever was habitable for simple life forms. The 
answer, a historic "yes," came from two mudstone slabs that the rover sampled 
with its drill. Analysis of these samples revealed the site was once a 
lakebed with mild water, the essential elemental ingredients for life, and a 
type of chemical energy source used by some microbes on Earth. If Mars had 
living organisms, this would have been a good home for them.

Other important findings during the first Martian year include:

-- Assessing natural radiation levels both during the flight to Mars and on 
the Martian surface provides guidance for designing the protection needed for 
human missions to Mars.

-- Measurements of heavy-versus-light variants of elements in the Martian 
atmosphere indicate that much of Mars' early atmosphere disappeared by 
processes favoring loss of lighter atoms, such as from the top of the 
atmosphere. Other measurements found that the atmosphere holds very little, 
if any, methane, a gas that can be produced biologically.

-- The first determinations of the age of a rock on Mars and how long a rock 
has been exposed to harmful radiation provide prospects for learning when 
water flowed and for assessing degradation rates of organic compounds in 
rocks and soils.

Curiosity paused in driving this spring to drill and collect a sample from a 
sandstone site called Windjana. The rover currently is carrying some of the 
rock-powder sample collected at the site for follow-up analysis.

"Windjana has more magnetite than previous samples we've analyzed," said 
David Blake, principal investigator for Curiosity's Chemistry and Mineralogy 
(CheMin) instrument at NASA's Ames Research Center, Moffett Field, 
California. "A key question is whether this magnetite is a component of the 
original basalt or resulted from later processes, such as would happen in 
water-soaked basaltic sediments. The answer is important to our understanding 
of habitability and the nature of the early-Mars environment."

Preliminary indications are that the rock contains a more diverse mix of clay 
minerals than was found in the mission's only previously drilled rocks, the 
mudstone targets at Yellowknife Bay. Windjana also contains an unexpectedly 
high amount of the mineral orthoclase, This is a potassium-rich feldspar that 
is one of the most abundant minerals in Earth's crust that had never before 
been definitively detected on Mars.

This finding implies that some rocks on the Gale Crater rim, from which the 
Windjana sandstones are thought to have been derived, may have experienced 
complex geological processing, such as multiple episodes of melting.

"It's too early for conclusions, but we expect the results to help us connect 
what we learned at Yellowknife Bay to what we'll learn at Mount Sharp," said 
John Grotzinger, Curiosity Project Scientist at the California Institute of 
Technology, Pasadena. "Windjana is still within an area where a river flowed. 
We see signs of a complex history of interaction between water and rock."

Curiosity departed Windjana in mid-May and is advancing westward. It has 
covered about nine-tenths of a mile (1.5 kilometers) in 23 driving days and 
brought the mission's odometer tally up to 4.9 miles (7.9 kilometers).

Since wheel damage prompted a slow-down in driving late in 2013, the mission 
team has adjusted routes and driving methods to reduce the rate of damage.

For example, the mission team revised the planned route to future 
destinations on the lower slope of an area called Mount Sharp, where 
scientists expect geological layering will yield answers about ancient 
environments. Before Curiosity landed, scientists anticipated that the rover 
would need to reach Mount Sharp to meet the goal of determining whether the 
ancient environment was favorable for life. They found an answer much closer 
to the landing site. The findings so far have raised the bar for the work 
ahead. At Mount Sharp, the mission team will seek evidence not only of 
habitability, but also of how environments evolved and what conditions 
favored preservation of clues to whether life existed there.

The entry gate to the mountain is a gap in a band of dunes edging the 
mountain's northern flank that is approximately 2.4 miles (3.9 kilometers) 
ahead of the rover's current location. The new path will take Curiosity 
across sandy patches as well as rockier ground. Terrain mapping with use of 
imaging from NASA's Mars Reconnaissance Orbiter enables the charting of 
safer, though longer, routes.

The team expects its will need to continually adapt to the threats posed by 
the terrain to the rover's wheels but does not expect this will be a 
determining factor in the length of Curiosity's operational life.

"We are getting in some long drives using what we have learned," said Jim 
Erickson, Curiosity Project Manager at NASA's Jet Propulsion Laboratory (JPL) 
in Pasadena, California. "When you're exploring another planet, you expect 
surprises. The sharp, embedded rocks were a bad surprise. Yellowknife Bay 
was a good surprise."

JPL manages NASA's Mars Science Laboratory Project for NASA's Science Mission 
Directorate at the agency's headquarters in Washington, and built the 
project's Curiosity rover.

For more information about Curiosity, visit:

http://www.nasa.gov/msl 

and

http://mars.jpl.nasa.gov/msl/ 

You can follow the mission on Facebook at:

http://www.facebook.com/marscuriosity 

and on Twitter at:

http://www.twitter.com/marscuriosity 

-end-

Dwayne Brown
Headquarters, Washington
202-358-1726
dwayne.c.brown at nasa.gov 

Guy Webster
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-6278
guy.webster at jpl.nasa.gov