While drilling has fractured rocks, this is the first time the instrument has ever accidentally pulled a whole chunk from the ground, according to the space agency Curiosity had a 28.6-pound rock dubbed "Atacama" stuck to its arm for a while. NASA / JPL-Caltech NASA’s  Curiosity  rover has been roaming Mars for nearly 14 years, hunting for signs that it once hosted environments that could have allowed ancient microbes to thrive. But on April 25, the rover ran into a problem: Its robotic arm got stuck while sampling a stone. On that day, Curiosity drilled into a flattish rock about 1.5 feet wide and 6 inches thick that weighed roughly 28.6 pounds. It’s dubbed “Atacama” after a Chilean desert, the driest mid-latitude desert on Earth—a tough place to survive.…