It began may 25, 1787 and ended September 17 the same year.
Vasco de Game was the FIRST to reach india by sea, so he was indeed an explorer.
Henry the Navigator (no offense to him) was a joke. His title if fooling everyone, as he himself never even sailed once, he always sent others to do it for him (as he was a prince) This is your answer.
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Bartholomeu Dias sailed around the southernmost tip of africa in 1488, so he was an explorer too.
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Your answer is Henry