The bow of the U.S. Coast Guard Cutter Healy at the North Pole, Sept. 5, 2015. Healy became the first U.S. vessel to reach the North Pole unaccompanied last week on a cruise that brought Scripps Institution of Oceanography, UC San Diego, oceanographer Jim Swift to the region to repeat a hydrographic survey done in 1994 and 2005. At this time of year, the sun doesn't set at the North Pole, instead moving in a circular pattern above the horizon. Photo: Cory Mendenhall, US Coast Guard
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