September 03, 2012
Credit: Credit: NASA Jet Propulsion Laboratory
Guy Norris Los Angeles
Less than a month after its touchdown, NASA's Curiosity rover is already revealing a wealth of new detail about Mars—even before driving for any significant distance.
Moreover, scientists are confident the startling high-definition images of inclined strata and other significant geological phenomena transmitted late last month from Curiosity are merely the tip of the iceberg as it begins its trek toward the base of nearby Mount Sharp, the central feature of the Gale Crater in which it landed. The rover, which landed on Aug. 5, is tasked with assessing the past and present habitability of Mars (see p. 28).
Following two short moves to check its mobility and test bedrock exposed at the landing site by one of the sky crane's thrusters, Curiosity began its first major drive on Aug. 28 to a science destination about a quarter-mile (400 meters) away. Covering approximately 52 ft. on its 22nd sol (Martian day) after landing, the first leg of Curiosity's journey will terminate several weeks from now at a spot named Glenelg, where operators at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif., have spotted a promising conjunction of three terrain types.
The target-rich zone will mark the first significant opportunity for the rover's 7-ft.-long robotic arm and drill to study sedimentary rocks for signs of organics. The arm supports a 73-lb. turret, which houses a percussive drill as well as an Alpha Particle X-ray Spectrometer and a sample processing Collection for In-Situ Martian Rock Analysis subsystem. Also mounted is a dust-removal tool for brushing the surfaces of sample rocks, and a close-up Mars Hand Lens Imager.
The study of accumulated rock-forming sediments is among the key targets for the mission, which hopes to interpret the planet's environmental record preserved within the layers. Clues to climate change, and the possible transitions from habitable to non-habitable conditions, are expected to be found in these layers.
This was all the more reason for the excitement caused on Aug. 27 when JPL unveiled a newly processed mosaic of high-definition images from Curiosity that showed “unexpected” geological features including multiple sequences of exposed, tilted strata of a sort never before seen on Mars.
“The cool thing is the cameras have discovered something we were unaware of,” says mission chief scientist John Grotzinger. “This thing jumped out at us as being very different to what we expected,” he adds. Situated in the low-lying foothills beyond the dune field between the rover and the base of Mount Sharp, the inclined layers are a “spectacular feature” that could only be viewed clearly from low angles.