Watch a 4K replay of the Atlas 5 launching for the National Reconnaissance Office

Early Friday morning, the 8-million-pound mobile service tower was retracted from around the Atlas 5 rocket, revealing the 189-foot-tall vehicle for liftoff from Vandenberg Air Force Base, California, carrying the commercial WorldView 4 Earth-imaging satellite.

A United Launch Atlas 5 rocket is set to launch the U.S. Air Force’s sixth and final Advanced Extremely High Frequency communications satellite from Cape Canaveral. This timeline shows the major mission events planned over a nearly six-hour flight to an optimized geostationary transfer orbit.

A new era in GPS navigation launched Sunday, when a SpaceX Falcon 9 rocket climbed into orbit with a Lockheed Martin-built satellite designed to beam higher-power positioning, navigation and timing signals around the world, providing military and civilian users with more accurate data that is more resistant to growing jamming threats.