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Aleksei Chirikov served as Bering's lieutenant during the First Kamchatka Expedition. This expedition, which took place from 1725 to 1730, aimed to explore and map the northeastern coast of Asia and search for a passage connecting the Pacific and Atlantic oceans. Chirikov played a crucial role as Bering's right-hand man, assisting in navigation, decision-making, and ensuring the overall success of the expedition.