Cook’s third voyage to the Pacific and early scientific astronomy on the north-western coast of America: the sojourn at Nootka Sound in April 1778

Cook’s third voyage to the Pacific and early scientific astronomy on the north-western coast of America: the sojourn at Nootka Sound in April 1778

Between 1768 and 1778 England’s premier maritime explorer, James Cook, made three much-published and very successful expeditions to the Pacific. Astronomy played a vital role in navigation and coastal cartography, and consequently there were astronomers on all three Pacific expeditions. On the final voyage Cook would lose his life in Hawaii, but not before exploring the north-western coast of the American continent and visiting Nootka Sound on the western shores of Vancouver Island.

In this paper we review the challenge of accurately determining latitude and longitude in the eighteenth century; provide biographical information about the three astronomers on Cook’s Third Voyage (Cook, King and Bayly); examine the range of astronomical instruments used during the Voyage, and the associated instrument-makers; describe the various types of astronomical observations made for latitude and longitude determinations; and review the observations that were made at Nootka Sound during the 3-week stopover of the Resolution and Discovery in April 1778.