Fireman Joseph Guenther, a member of the Coast Guard Cutter Polar Star's main propulsion division, relays a message to the cutter’s engineering control central while Petty Officer 2nd Class Keith Bryan, a machinery technician in the Polar Star’s main propulsion division, observes during engineering casualty exercises in the Ross Sea, near Antarctica, Feb. 4, 2016. The drills simulate emergency situations in engine spaces for the ship’s engineers to learn and apply their initial response techniques. (U.S. Coast Guard photo by Petty Officer 2nd Class Grant DeVuyst)