
Astronaut Chris Cassidy conducts a session with a pair of bowling-ball-sized free-flying satellites known as SPHERES.

Astronaut Chris Cassidy conducts a session with a pair of bowling-ball-sized free-flying satellites known as SPHERES.

Expedition 38 crew members take a break from training at NASA’s Johnson Space Center to pose for a crew portrait.

NASA astronaut Rick Mastracchio, wearing his Extravehicular Mobility Unit (EMU) spacesuit.

On August 15, at the Naval Station Norfolk near NASA’s Langley Research Center in Virginia, NASA and the U.S. Navy…

Engineers work with the Integrated Science Instrument Module for the James Webb Space Telescope inside the thermal vacuum chamber at…

An overhead glimpse inside the thermal vacuum chamber at NASA’s Goddard Space Flight Center in Greenbelt, Md., as engineers ready…

Twilight, noctilucent clouds and aurora viewed on June 9, 2013 from Alberta, Canada.

Portrait of new astronaut candidate Victor J. Glover.

Portrait of new astronaut candidate Christina M. Hammock.