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Southern Ocean

The US Coast Guard Cutter Polar Star, with 75,000 horsepower and its 13,500-ton weight, is guided by its crew to break through Antarctic ice enroute to the southern continent. The ship remains the world’s most powerful non-nuclear icebreaker. The USGCC Polar Star is the Coast Guard’s only operational heavy icebreaker capable of conducting Antarctic ice operations and is an integral part of the yearly resupply of the National Science Foundation’s McMurdo Station. Photo courtesy of US Coast Guard/ Chief Petty Officer David Mosley.