New Landing Method Make Mission Challenging, Risky
NASA's most advanced mobile robotic laboratory, which will
examine one of the most intriguing areas on Mars, is in final
preparations for a launch from Florida's Space Coast at 1025 EST on
November 25. The Mars Science Laboratory (MSL) mission will carry
Curiosity, a rover with more scientific capability than any ever
sent to another planet. The rover is now sitting atop an Atlas V
rocket awaiting liftoff from Cape Canaveral Air Force Station.
"Preparations are on track for launching at our first
opportunity," said Pete Theisinger, MSL project manager at NASA's
Jet Propulsion Laboratory (JPL) in Pasadena, Calif. "If weather or
other factors prevent launching then, we have more opportunities
through Dec. 18."
Scheduled to land on the Red Planet in August 2012, the one-ton
rover will examine Gale Crater during a nearly two-year prime
mission. Curiosity will land near the base of a layered mountain 3
miles (5 kilometers) high inside the crater. The rover will
investigate whether environmental conditions ever have been
favorable for development of microbial life and preserved evidence
of those conditions.
"Gale gives us a superb opportunity to test multiple potentially
habitable environments and the context to understand a very long
record of early environmental evolution of the planet," said John
Grotzinger, project scientist for MSL at the California Institute
of Technology in Pasadena. "The portion of the crater where
Curiosity will land has an alluvial fan likely formed by
water-carried sediments. Layers at the base of the mountain contain
clays and sulfates, both known to form in water."
Curiosity is twice as long and five times as heavy as earlier
Mars rovers Spirit and Opportunity. The rover will carry a set of
10 science instruments weighing 15 times as much as its
predecessors' science payloads. A mast extending to 7 feet above
ground provides height for cameras and a laser-firing instrument to
study targets from a distance. Instruments on a 7-foot-long arm
will study targets up close. Analytical instruments inside the
rover will determine the composition of rock and soil samples
acquired with the arm's powdering drill and scoop. Other
instruments will characterize the environment, including the
weather and natural radiation that will affect future human
missions.
"Mars Science Laboratory builds upon the improved understanding
about Mars gained from current and recent missions," said Doug
McCuistion, director of the Mars Exploration Program at NASA
Headquarters in Washington. "This mission advances technologies and
science that will move us toward missions to return samples from
and eventually send humans to Mars."
The mission is challenging and risky. Because Curiosity is too
heavy to use an air-bag cushioned touchdown, the mission will use a
new landing method, with a rocket-powered descent stage lowering
the rover on a tether like a kind of sky-crane.
The mission will pioneer these precision landing methods during
the spacecraft's crucial dive through Mars' atmosphere next August
to place the rover onto a smaller landing target than any
previously for a Mars mission. The target inside Gale Crater is
12.4 miles (20 kilometers) by 15.5 miles (25 kilometers). Rough
terrain just outside that area would have disqualified the landing
site without the improved precision.
No mission to Mars since the Viking landers in the 1970s has
sought a direct answer to the question of whether life has existed
on Mars. Curiosity is not designed to answer that question by
itself, but its investigations for evidence about prerequisites for
life will steer potential future missions toward answers. (Images
courtesy NASA)