The U.S. Navy's fourth Mobile User Objective System (MUOS) satellite, encapsulated in a 5-meter payload fairing, is mated to an Atlas V booster inside the Vertical Integration Facility at Cape Canaveral's Space Launch Complex-41.

[SatNews] A United Launch Alliance Atlas V 551 will launch the U.S. Navy’s fourth Mobile User Objective System (MUOS-4) satellite, built by Lockheed Martin on Monday, August 31, 2015, from Space Launch Complex-41 at Cape Canaveral Air Force Station, Florida. The 44-minute launch window opens at 6:07 a.m. EDT.
 

The live broadcast will begin at 5:47 a.m. EDT. The Navy’s Mobile User Objective System (MUOS) is a next-generation narrowband tactical satellite communications system designed using a combination of orbiting satellites and relay ground stations to significantly improve communications for U.S. forces on the move. MUOS will provide new beyond-line-of-sight secure communications capabilities, with smartphone-like simultaneous voice, video and data to connect military users almost anywhere around the globe.

MUOS-4 will mark the 56th Atlas V since the vehicle’s inaugural launch in August 2002 and the sixth in the 551 configuration. Previous missions launched on Atlas V 551 missions include three MUOS missions as well as the New Horizons mission to Pluto and the Juno mission to Jupiter.