Photos: Atlas 5 rolls out for Friday launch to GPS constellation

The United Launch Alliance Atlas 5 rocket stands atop Space Launch Complex 3-East at Vandenberg Air Force Base in California on the eve of Wednesday’s NROL-79 satellite-deployment mission for the National Reconnaissance Office.

Another countdown for United Launch Alliance’s next Delta 4-Heavy rocket mission ended without a liftoff Wednesday after a computer sequencer detected a potential problem just before engine ignition.

Elements of the next U.S. commercial cargo-delivery trip to the International Space Station are coming together at Kennedy Space Center for the planned March 10 liftoff.