Photos: 200th Atlas-Centaur launches MUOS 3

The preliminary weather forecast for Tuesday evening’s Atlas 5 rocket launch carrying a Navy communications satellite predicts a 60 percent chance of acceptable conditions, with thick clouds the main threat against flying at 7:43 p.m. EST as scheduled.

A massive U.S. Navy satellite to launch from Cape Canaveral in January has arrived in Florida, kicking off a campaign to ready the mobile communications craft for flight.

The massive U.S. Navy communications satellite launched from Cape Canaveral two weeks ago has completed prescribed maneuvers to reach geosynchronous orbit and successfully unfurled its umbrella-like antenna reflectors.