Photos: Thursday’s Atlas 5 rollout to launch pad

The SMAP observatory to map soil moisture distribution from 426 miles in space and its workhorse booster have been cleared for launch Thursday morning from California.

The Pentagon has awarded at least $162 million in contracts to Aerojet Rocketdyne and United Launch Alliance for development of the AR1 and BE-4 rocket engines, candidates to power the first stage of a next-generation rocket and replace the Russian-made engine currently flying on the Atlas 5 launcher.

The U.S. Air Force’s X-37B space plane concluded its third mission, streaking through the atmosphere over the Pacific Ocean and gliding to an automated landing on a runway at Vandenberg Air Force Base, Calif., after spending a record 675 days in orbit.