Space News reports that United Launch Alliance “launched a classified National Reconnaissance Office spy satellite on a Delta 4 Heavy rocket June 22 at 5:18 a.m. Eastern from Space Launch Complex-37 (SLC-37) at Cape Canaveral Space Force Station, Florida.”

It was ULA’s second attempt “of this launch that had been previously scheduled for June 21 but was delayed, the company said, ‘due to an issue with a ground systems pneumatic valve.’” About four minutes into flight, “the outer boosters of the three-core Delta 4 Heavy separated.”

The second stage “separated about two minutes later.” This mission was “ULA’s first launch of 2023.” The company in May 2019 “received a U.S. Air Force contract to launch NROL-68.”

The Delta 4 Heavy configuration “first launched in December 2004.” Each of the Delta 4 Heavy’s common booster cores “is powered by Aerojet [Rocketdyne’s] RS-68A main engines.” The Delta cryogenic second stage “is powered by an RL10C-2-1 engine.”