Will Curiosity’s drill uncover evidence of past life on Mars?
NASA’s Mars Curiosity has achieved another milestone in its search for signs of past life on the Red Planet– successfully drilling into a rock which scientists believe once held water.
The rover employed a drill attached to the end of its 7-foot-long robotic arm to drill into the flat, veined Martian rock. Seven minutes and 2.5 inches later, Curiosity had removed an aspirin-sized amount of powder to be analyzed in its onboard laboratory.
“It was a perfect execution,” said drill engineer Avi Okon at the NASA Jet Propulsion Laboratory on Saturday.
“This is the biggest milestone accomplishment for the Curiosity team since the sky-crane landing last August, another proud day for America,” added Professor John Grotizinger, chief scientist for the mission.
The event marks the first time that a space craft has probed beneath the surface of another planet, though past missions have collected minor scrapings of exterior rock and dirt layers on Mars and snatched up lunar rocks for transport to Earth.
Curiosity began its complex drilling mission by hammering down briefly on a rock last weekend to check the rover’s machinery, followed by drilling a smaller test hole about 2 centimeters deep. The initial test produced enough Martian powder to be transferred into Curiosity’s acquisition chamber, in order to cleanse the area of any previous contaminants. The larger, second hole generated powdered rock that will be analyzed by the rover’s Chemin and Sam labs.
Several days remain before the rover transfers the powdered sample to its interior, with several more days to follow until the resulting data is transmitted back to Curiosity’s team at NASA’s Jet Propulsion Laboratory in Pasadena, California. The caution and gradual pace is deliberate and necessary, as project engineers carefully maneuver the rather expensive craft (the mission’s total cost is $2.5 billion) across Mars’ surface to conduct a series of unprecedented operations. In this latest undertaking, NASA must be careful not to damage the rover’s drill bit on the Martian rock, or contaminate the sample with remnants of Curiosity’s earthly origins.
Curiosity’s drill is the rover’s last tool to be tested, having already completed several technically impressive feats, including an innovative landing using a rocket-powered platform and cables to descend into Mars’ Gale Crater last August.
Scientists back on Earth speculate that water once percolated through the rocks that Curiosity is now drilling, creating fracture networks and minerals that precipitated to form the white mineral material observed by the rover’s team, believed to be hydrated calcium sulfate. The rover also observed several small concretions, or spherules, suggesting the presence of water on Mars’ surface in the distant past. The current drill site is named after the late Mars Science Laboratory deputy project manager John W. Klein, who helped pave the way for the Mars rover’s path today.
Despite what may seem like a slow pace across the Martian surface—averaging a modest 100-150 meters on a good day—Curiosity has already returned a wealth of information to scientists back home. The craft has transmitted 18,226 images and almost 10 gigabytes of raw information about the planet’s geology, soil composition, mineral chemistry, and atmosphere since landing in August of 2012.
Now, as Curiosity wraps up its initial drilling test in the coming weeks, the rover will prepare to embark on its primary mission of ascending nearby Mount Sharp, where scientists hope to discover evidence that microbes once thrived on the surface of our planetary neighbor.