Capt. Michael Davanzo, commanding officer of the Coast Guard Cutter Polar Star, outlines the cutter’s recent Antarctic mission on a chart during an interview with KPIX while the cutter is in a Vallejo, Calif., dry dock facility undergoing depot-level maintenance prior to the cutter’s next patrol, April 16, 2018. The Seattle-based crew aboard Polar Star recently returned from McMurdo Sound in support the U.S. Antarctic Program and the National Science Foundation (NSF) which required the cutter's crew to break through more 15 miles of ice in McMurdo Sound, sometimes as much as 10 feet in thickness, to resupply NSF's McMurdo and Amundsen-Scott South Pole stations. U.S. Coast Guard photo by Petty Officer 1st Class Matthew S. Masaschi.