SCHRIEVER AIR FORCE BASE, Colo. -- Col. Traci Kueker-Murphy, 310th Space Wing commander, and Lieutenant Col. Paxton Mellinger, 6th Space Operations Squadron commander, hold a celebratory "check" for Col. Stephen Slade, 310th Operations Group commander, to sign on Tuesday, Mar. 20, 2018. The "check" was later presented as a memento to 6 SOPS crew members that completed the squadron's 40,000th satellite contact. (U.S. Air Force photo/Senior Airman Laura Turner)