One Of Four Sites To Be Selected
Four intriguing places on Mars have
risen to the final round as NASA selects a landing site for its
next Mars mission, the Mars Science Laboratory.
The agency had a wider range of possible landing sites to choose
from than for any previous mission, thanks to the Mars Science
Laboratory's advanced technologies, and the highly capable orbiters
helping this mission identify scientifically compelling places to
explore.
Mars Science Laboratory project leaders at NASA's Jet Propulsion
Laboratory in Pasadena, CA chose the four this month, after seeking
input from international Mars experts and from engineers working on
the landing system and rover capabilities.
The sites, alphabetically, are: Eberswalde, where an ancient
river deposited a delta in a possible lake; Gale, with a mountain
of stacked layers including clays and sulfates; Holden, a crater
containing alluvial fans, flood deposits, possible lake beds and
clay-rich deposits; and Mawrth, which shows exposed layers
containing at least two types of clay.
"All four of these sites would be great places to use our roving
laboratory to study the processes and history of early Martian
environments and whether any of these environments were capable of
supporting microbial life and its preservation as biosignatures,"
said John Grotzinger of the California Institute of Technology,
Pasadena. He is the project scientist for the Mars Science
Laboratory.
The mission's capabilities for landing more precisely than ever
before and for generating electricity without reliance on sunshine
have made landing sites eligible that would not have been
acceptable for past Mars missions. During the past two years,
multiple observations of dozens of candidate sites by NASA's Mars
Reconnaissance Orbiter have augmented data from earlier orbiters
for evaluating sites' scientific attractions and engineering
risks.
JPL is assembling and testing the Mars Science Laboratory
spacecraft for launch in fall 2009. Paring the landing-site list to
four finalists allows the team to focus further on evaluating the
sites and planning the navigation. The mission plan calls for the
rover to spend a full Mars year (23 months) examining the
environment with a diverse payload of tools.
After evaluating additional Mars orbiter observations of the
four sites, NASA will hold a fourth science workshop about the
candidates in the spring and plans to choose a final site next
summer. Three previous landing-site science workshops for Mars
Science Laboratory, in 2006, 2007 and two months ago, drew
participation of more than 100 Mars scientists and presentations
about more than 30 sites.
For their Mars landings in 2004, Spirit and Opportunity needed
safe target areas about 40 miles long. Mars Science Laboratory is
designed to hit a target area roughly 12 miles in diameter.