Tech. Sgt. PJ Peters, U.S. Air Force Reserve jets propulsion technician, assigned to the 459th Air Refueling Wing, Joint Base Andrews, Maryland, closes a fuel tank valve as the KC-135 Stratotanker receives fuel from Finnish personnel during Arctic Challenge Exercise 2021, at Rovaniemi Air Base, Finland, June 14. ACE 21 is a joint multinational exercise to train units in the orchestration and conduct of air operations, to include execution of tactics and command and control procedures and interoperability. Continual exercises and interactions between allied and partner forces, such as ACE 21, allow us to work together as a team to address security threats in and beyond Europe and enable all participants to contribute to international conditions. (U.S. Army photo by Sgt. Paul Abacon)