170916-N-NQ487-744 ATLANTIC OCEAN (Sept. 8, 2017) Machinist's Mate 2nd Class George Mathis takes a sample of liquid oxygen in an O2N2 production room aboard the aircraft carrier Harry S. Truman (CVN 75). Harry S. Truman is underway conducting carrier qualifications in preparation for future operations. (U.S. Navy photo by Mass Communication Specialist Seaman Kaysee Lohmann/Released)