A United Launch Alliance Delta 4-Heavy rocket lifted off from Vandenberg Air Force Base in California at 1:47 p.m. PDT (4:47 p.m. EDT; 2047 GMT) Monday with a classified satellite for the National Reconnaissance Office, the U.S. government’s spy satellite agency.

Ground controllers sent commands Saturday for the International Space Station’s Canadian-built robotic arm to release a SpaceX Dragon cargo capsule, ending the ship’s nearly four-week stay at the orbiting research complex.

Elements of the next U.S. commercial cargo-delivery trip to the International Space Station are coming together at Kennedy Space Center for the planned March 10 liftoff.