Photos: Atlas 5 rolls out for launch

The U.S. Air Force has identified the launch of a next-generation GPS navigation satellite for the first in a series of competitive rocket procurements between United Launch Alliance and SpaceX, service officials announced Wednesday.

The main engine rumbling to life. Ice shards breaking free. The rocket lumbering off the pad. The battle against gravity being won once again. That was the scene as the Atlas 5 took flight to cap a generation of Global Positioning System satellites.

This is our comprehensive fact sheet previewing the United Launch Alliance Atlas 5 rocket deployment of the classified NROL-52 payload for the National Reconnaissance Office.