An Atlas V rocket is scheduled to launch from Space Launch Complex 41 at Cape Canaveral Air Force Station carrying the MUOS-1 satellite today. The launch is to take place between 5:46pm and 6:30pm EST or 22:46 to 23:30 GMT.
This is a landmark launch for the United Launch Alliance team as it is the 200th launch featuring the Centaur second stage rocket. The Centaur upper stage has been in use since it’s inaugural flight ontop of an Atlas booster in May 1962 from Launch Complex 36A.
The MUOS-1 spacecraft is the first of a constellation of 5 communication satellites for the US Navy. The MUOS acronym stands for Mobile User Objective System and is designed to be the next generation narrowband tactical communications system. Its main objective is to improve the ground communications to mobile US forces around the world.
The Atlas V will be flying in the 551 configuration. This consists a single Atlas V main booster, 5 solid rocket boosters and a 5 meter diameter medium payload fairing.
The flight plan calls for a 92 second burn of the solid rocket motors to help lift the rocket through the heaviest part of the lower atmosphere. The SRBs will burn out and be jettisoned between 104 and 106 minutes into the flight.
The main Atlas V booster will continue lifting the rocket until the T +264s mark at which time it will cutoff and be jettisoned at T +270. The Centaur will have three burns, the first starting 10 seconds after the Atlas V booster separation, the final one finishing at T + 2h57m.
The MUOS-1 spacecraft will separate about 4 minutes after the final burn leaving the Centaur to decay and burn up when re-entering the atmosphere.