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The French explorer Jean-François de Galaup, comte de Lapérouse, was 47 years old when he disappeared during his second expedition in the Pacific Ocean. His ships, the Astrolabe and the Boussole, were last seen on 17 June 1788 off Vanikoro Island in the Solomon Islands. The fate of the expedition and its crew remained a mystery for over 150 years, until the wreck of the Astrolabe was discovered in 1964.