Photos: Most powerful Atlas 5 puts 15,000-pound satellite in orbit

The launch of a United Launch Alliance Delta 4-Heavy rocket from Cape Canaveral was aborted three seconds before a planned liftoff at 3:28 a.m. EDT (0728 GMT). The rocket was set to loft a classified payload for the National Reconnaissance Office, the U.S. government’s spy satellite agency.

Joining the payload with its ride to space, United Launch Alliance crews today placed the next Global Positioning System satellite atop an Atlas 5 rocket for blastoff July 15.

SpaceX has postponed its next launch from the Kennedy Space Center indefinitely to examine data from a recent payload fairing test for another customer.