Test Time Air Force Senior Airman Kenneth Johnson receives a COVID-19 test during exercise Astral Knight at Larissa Air Base, Greece, May 21, 2021. The exercise enhances the readiness, strength and cohesion between the U.S., Albania, Croatia, Greece, Italy, Slovenia and units from around European Command. SHARE: Download: Full Size (0.73 MB) Tags: Air Force, Training, Astral Knight, coronavirus, covid19vaccine Credit: Air Force Tech. Sgt. Alex Echols VIRIN: 210521-F-DY859-0057C.JPG Photo Gallery