Celestial skies stream light onto a Canadian Coast Guard icebreaker as it cuts a trail through a frozen expanse of Arctic Ocean in Canada’s Northwest Territories. The Canadian Coast Guard was part of a mission to explore the sunken wreckage of the H.M.S. Breadalbane, a British ship that went down in the 1850s while on a mission to find survivors of the ill-fated Franklin expedition to map the Northwest Passage.