Capt. Matthew Walker, commanding officer of Coast Guard Cutter Polar Star, thanks the ship's crew after safely escorting the fishing vessel Antarctic Chieftain out of the ice in the Southern Ocean, Feb. 15, 2015. Polar Star’s crew assisted the Antarctic Chieftain after the vessel was disabled and beset by ice. (U.S. Coast Guard photo by Petty Officer 1st Class George Degener)