Photos: Atlas 5 on the pad for X-37B launch

A United Launch Alliance Atlas 5 rocket with a new type of solid rocket booster emerged from its hangar Tuesday evening for the 1,800-foot rollout to pad 41 at Cape Canaveral, moving into position for liftoff Wednesday with a classified National Reconnaissance Office payload.

Clad in pressurized spacesuits, two Russian cosmonauts headed outside the International Space Station on Wednesday and hand-released four tiny CubeSats and installed hardware for a German experiment to track animal migration.

United Launch Alliance technicians were allowed to return to the Atlas 5 pad Tuesday as firefighters continued to wage air and ground campaigns against the wildfire burning at Vandenberg Air Force Base in California.