Outside the International Space Station, a two-armed robot named Dextre helps NASA locate an ammonia leak. Robotic operators had Dextre grab onto a tool called the Robotic External Leak Locator, which "sniffed" for traces of ammonia.
The Arecibo Observatory is an icon of astronomy. The giant radio telescope in Puerto Rico is the second-largest of its kind on Earth. See photos of Arecibo over the years in our gallery here.