United Launch Alliance (ULA) last week launched a second classified spy satellite for the National Reconnaissance Office from a launch pad at Vandenberg AFB, Calif., the company said.

A Delta 4 rocket carried the satellite into its polar orbit on Jan. 21, according to a statement released by ULA, which is a joint venture between Lockheed Martin [LMT] and Boeing [BA]. The first of the two NRO satellite launches took place out of Cape Canaveral, Fla., late last year.

“Today’s successful launch represents the culmination of five years’ hard work and exceptional skill in modifying the launch system to establish the west coast heavy lift capability for the nation and to integrate this important mission,” ULA Vice President Jim Sponnick said in a statement.

ULA’s next launch is scheduled for March, when the Air Force’s Atlas 5 Orbital Test Vehicle-2 is to be launched out of Cape Canaveral.