U.S. Coast Guard Petty Officers Christopher Tull and Kyle McGann, members of the military dive team aboard Coast Guard Cutter Polar Star, prepare to conduct an underwater inspection of the ship while moored at the National Science Foundation's McMurdo Station, Antarctica, Jan. 23, 2015. Divers inspect the ship's hull and propellers for any damage that may have occurred while breaking ice. (U.S. Coast Guard photo by Petty Officer 1st Class George Degener)