Posted: Fri, Jan 20, 2012, 6:43 AM ET (1143 GMT)

A Delta 4 rocket sucecssfully launched the fourth in a series of US military communications satellites on Thursday. The Delta 4 Medium+Plus (5,4) rocket lifted off on schedule at 7:38 pm EST Thursday (0038 GMT Friday) and placed the WGS-4 satellite into a geosynchronous transfer orbit. The satellite is the fourth in the series of Wideband Global SATCOM satellites that provide military communications services. The launch is the first of 11 EELV-class launches planned for 2012, two for NASA and the remainder for national security missions.