[meteorite-list] Opportunity Rover Examining Odd Mars Rocks at Valley Overlook

[Ron Baalke]

http://www.jpl.nasa.gov/news/news.php?feature=4502

Rover Examining Odd Mars Rocks at Valley Overlook
Jet Propulsion Laboratory
March 5, 2015

THINGS TO KNOW:

o Rover is examining rocks with composition unlike any previously found 
on Mars

o Opportunity has switched to a new version of its flight software, with 
plans for flash memory reformatting.

o Remaining distance to reach marathon-race equivalent is 140 yards (128 
meters)

NASA's Mars Exploration Rover Opportunity climbed last month to an overlook 
for surveying "Marathon Valley," a science destination chosen because 
spectrometer observations from orbit indicate exposures of clay minerals.

Near the overlook, it found blocky rocks so unlike any previously examined 
on Mars that the rover team has delayed other activities to provide time 
for a thorough investigation.

"We drove to the edge of a plateau to look down in the valley, and we 
found these big, dark-gray blocks along the ridgeline," said Opportunity 
Project Scientist Matt Golombek of NASA's Jet Propulsion Laboratory, Pasadena, 
California. "We checked one and found its composition is different from 
any ever measured before on Mars. So, whoa! Let's study these more before 
moving on."

The first rock checked at the site has relatively high concentrations 
of aluminum and silicon, and an overall composition not observed before 
by either Opportunity or its twin rover, Spirit. This was determined by 
examining the rock, called "Jean-Baptiste Charbonneau," with the Alpha 
Particle X-ray Spectrometer instrument on the end of Opportunity's robotic 
arm. The next target rock at the site is called "Sergeant Charles Floyd." 
The team's target-naming theme in the area is from the Lewis and Clark 
expedition.

Although the rocks are gray, the visible-light spectrum of the Charbonneau 
type has more purple than most Mars rocks, and the spectrum of the Floyd 
type has more blue. Of the two types, the bluer rocks tend to lie higher 
on the ridge.

Actions to restore use of Opportunity's non-volatile flash file system 
will resume after inspection of the rocks on this ridge. Due to recurrent 
problems with the flash memory, including "amnesia events" and computer 
resets, Opportunity has been operating since late 2014 in a mode that 
avoids use of the flash memory.

Between the stops at Charbonneau and Floyd, the rover team uploaded to 
Opportunity a new version of the rover's flight software. The new version 
is designed to use only six of the rover's seven banks of flash memory. 
It will avoid the seventh bank, known to be a problem area.

The rover is using the new software, but a memory reformatting will be 
needed before resuming use of flash memory. After reformatting, the operations 
team will avoid use of the rover's arm for several days to make sure the 
flash file system is fixed and no longer causes resets. A reset during 
the use of the rover's arm would require a complex recovery effort.

As of March 5, Opportunity has driven 26.139 miles (42.067 kilometers) 
since it landed on Mars in January 2004. This brings it within 140 yards 
(128 meters) of reaching the distance of a marathon  footrace.

JPL, a division of the California Institute of Technology in Pasadena, 
manages the Mars Exploration Rover Project for NASA's Science Mission 
Directorate in Washington. For more information about Spirit and Opportunity, 
visit:

http://www.nasa.gov/rovers

http://marsrovers.jpl.nasa.gov

You can follow the project on Twitter and on Facebook at:

http://twitter.com/MarsRovers

http://www.facebook.com/mars.rovers


Media Contact

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

2015-078