SpaceX’s final Falcon 9 launch of the year carried a classified payload for the National Reconnaissance Office, the U.S. government’s spy satellite agency. SpaceX aborted a launch attempt Thursday morning to assess a second stage sensor reading, but the Falcon 9 successfully lifted off from the Kennedy Space Center at 9 a.m. EST (1400 GMT) Saturday. The rocket’s stage landed back at Cape Canaveral eight minutes later.

The U.S. Space Force says it will launch two GPS navigation satellites on reused Falcon 9 boosters next year through a restructured contract with SpaceX that saved taxpayers $52 million, the first time the military has agreed to fly operational national security payloads on previously-flown rockets.

SpaceX could use its Starship vehicles to clear out space debris in Earth orbit, alongside the program’s more publicized purpose of ferrying people and cargo to the moon and Mars, a company executive said.