U.S. Air Force Airman 1st Class Olavio Benito, 18th Logistics Readiness Squadron cryogenic production technician, samples pressure on an oxygen purity analyzer Sept. 12, 2017, at Kadena Air Base, Japan. Oxygen is run through a machine removing all of the moisture from the air before being cooled to -300 degrees Fahrenheit. This cooling causes the gaseous oxygen to turn into a compact, liquid form used by pilots and medical personnel. (U.S. Air Force photo/Senior Airman Quay Drawdy)