System CheckNASA's Curiosity rover snapped this closeup view of its tool turret flexing its seven-foot-long (two-meter-long) robot arm on August 20—the first time since landing on the red planet about two weeks ago.The car-size robotic geochemist conducted a series of health checks on itself, including unfolding its arm and making sure all five of its joints are in working order.Like a hand, at the tip of its appendage is a 2-foot-wide (0.6-meter-wide), 70-pound (32-kilogram) turret of five tools that will be used to collect and analyze rock and soil samples on Mars.(Get the full story of Curiosity's mission in the National Geographic e-book Mars Landing 2012.)—Andrew Fazekas
Image courtesy Caltech/NASA

Space Pictures This Week: "Blast" Crater, Mars Rover, More

A "stunning sky show," debris from an undersea volcano, and a Mars "blast zone" feature among the week's best space pictures.

August 24, 2012