NASA astronaut Chris Cassidy, Expedition 36 flight engineer, uses a digital still camera during a session of extravehicular activity (EVA) as work continues on the International Space Station. A little more than one hour into the spacewalk on July 16, 2013, European Space Agency astronaut Luca Parmitano (out of frame) reported water floating behind his head inside his helmet. The water was not an immediate health hazard for Parmitano, but Mission Control decided to end the spacewalk early.
Hi, Hokusai! This dramatic image features Hokusai in the foreground, famous for its extensive set of rays, some of which extend for over a thousand kilometers across Mercury's surface. | by NASA Goddard Photo and Video