The first of a new generation of U.S. missile warning satellites, the Space Based Infrared System (SBIRS) Geo-1, was quietly declared operational last month, two years after its launch.

Air Force Space Command declared SBIRS Geo-1 operational May 17 and recommended Integrated Tactical Warning and Attack Assessment certification of the asset to U.S. Strategic Command, Air Force Lt. Connie Dillon, a Space Command spokeswoman, said June 7 in response to a SpaceNews query. The Air Force has attributed Geo-1’s lengthy commissioning period to an onboard communications issue correctable via a software upload.

Built by Lockheed Martin Space Systems of Sunnyvale, Calif., SBIRS Geo-1 was launched May 7, 2011 from Cape Canaveral Air Force Station, Fla., atop a United Launch Alliance Atlas 5 rocket. The Air Force launched its companion spacecraft, SBIRS Geo-2, in March.