The crew of the U.S. Coast Guard Cutter Polar Star escorts the tanker vessel Maersk Peary as the tanker departs from the National Science Foundation’s McMurdo Station, Feb, 7, 2017. The Polar Star’s crew is responsible for providing a safe channel through the Antarctic ice for resupply ships that visit the station. (U.S. Coast Guard photo by Chief Petty Officer David Mosley)