[meteorite-list] NASA's Durable Spirit Sends Intriguing New Images From Mars

[Ron Baalke]

Dolores Beasley
Headquarters, Washington                       September 1, 2005
(Phone: 202/358-1753)

Guy Webster
Jet Propulsion Laboratory, Pasadena, Calif.
(Phone: 818/354-6278)

RELEASE: 05-244

NASA'S DURABLE SPIRIT SENDS INTRIGUING NEW IMAGES FROM MARS

Working atop a range of Martian hills, NASA's Spirit rover is 
rewarding researchers with tempting scenes filled with evidence 
of past planet environments.

"When the images came down and we could see horizon all the way 
around, that was every bit as exhilarating as getting to the top 
of any mountain I've climbed on Earth," said Chris Leger, a 
rover planner at NASA's Jet Propulsion Laboratory (JPL), 
Pasadena, Calif.

The summit sits 82 meters (269 feet) above the edge of the 
surrounding plains. It is 106 meters (348 feet) higher than 
the site where Spirit landed nearly 20 months ago. Spirit and 
twin rover, Opportunity, successfully completed their 
three-month prime missions in April 2004. They have inspected 
dozens of rocks and soil targets since then, continuing their 
pursuit of geological evidence about formerly wet conditions 
on Mars.

"Spirit has climbed to the hilltop and looked over the other 
side, but NASA did not do this just to say we can do it. The 
Mars rovers are addressing fundamental questions about 
Martian history and planetary environments," said NASA's Mars 
Exploration Program Director Doug McCuistion.

The crest of "Husband Hill" offers Spirit's views of possible 
routes into a basin to the south with apparently layered 
outcrops. Shortly after Spirit landed, it observed a cluster 
of seven hills about 3 kilometers (2 miles) east of its 
landing site. NASA proposed naming the range "Columbia Hills" 
in tribute to the last crew of Space Shuttle Columbia. The 
tallest of the hills commemorates Rick Husband, Columbia's 
commander.

Volcanic rocks covering the plain Spirit crossed on its way 
to the hills bore evidence of only slight alteration by 
water. When Spirit reached the base of the hills five months 
after landing, it immediately began finding rocks with 
wetter histories.

"This climb was motivated by science," said Steve Squyres of 
Cornell University, Ithaca, N.Y. Squyres is principal 
investigator for the rovers' science instruments. "Every 
time Spirit has gained altitude, we've found different rock 
types. Also, we're doing what any field geologist would do 
in an area like this: climbing to a good vantage point for 
plotting a route," he added. Researchers are viewing 
possible routes south to apparently layered ledges and to a 
feature dubbed "home plate," which might be a plateau of 
older rock or a filled-in crater.

The landing site and the Columbia Hills are within Gusev 
Crater, a bowl about 150 kilometers (95 miles) in diameter. 
It was selected for the Spirit mission because the shape 
of the terrain suggests the crater once held a lake. 
Volcanic deposits appear to have covered any sign of 
ancient lakebed geology out on the plain, but scientists 
say the hills expose older layers that have been lifted 
and tipped by a meteorite impact or other event.

"We're finding abundant evidence for alteration of rocks 
in a water environment," said Ray Arvidson of Washington 
University, St. Louis, Mo. Arvidson is deputy principal 
investigator for the rovers' science instruments. "What 
we want to do is figure out which layers were on top of 
which other layers. To do that it has been helpful to 
keep climbing for good views of how the layers are 
tilted to varying degrees. Understanding the sequence of 
layers is equivalent to having a deep drill core from 
drilling beneath the plains," he added.

Both Spirit and Opportunity have been extremely successful. 
Their solar panels are generating plenty of energy 
thanks to repeated dust-cleaning events. Spirit has 
driven 4,827 meters (3.00 miles), and Opportunity 5,737 
meters (3.56 miles).

JPL manages the Mars Exploration Rover project for NASA's 
Science Mission Directorate. For images and information 
about the rovers and their discoveries on the Web, visit:

http://www.nasa.gov/vision/universe/solarsystem/mer_main.html

For information about NASA and agency programs on the 
Internet, visit:

http://www.nasa.gov/home

-end-