1769 Transit of Venus observed from Tahiti while voyaging to (unsuccessfully) observe the 1761 Transit in Sumatra. Using the solar parallax values obtained from the 1769 transit, Hornsby wrote in "Philosophical Transitions" December 1771 that "the mean distance from the Earth to the Sun (is) 93,726,900 English miles." The radar-based value used today for the astronomical unit is . This is only a difference of eight-tenths of one percent. Considering what these astronomers had to work with, their results were "absolutely remarkable". 1769 Transit of Venus observed from Tahiti On June 3, 1769, British navigator Captain James Cook, British naturalist Joseph Banks, British astronomer Charles Green and
1769 Transit of Venus observed from Tahiti vast international endeavor. Even though the Seven Years' War was going on between Great Britain and France, the British Admiralty granted safe passage for French astronomer, Alexandre Guy Pingré on his way to view the 1761 transit. During Cook's journey to Tahiti, the French government instructed all its men-of-war not to harm the "Endeavour", since it was ‘out on enterprises of service to all mankind'. With the Venus Transits, astronomers of the eighteenth century illustrated unity in the scientific community. The entente, however, passed by noted astronomers and surveyors Charles Mason and Jeremiah Dixon, who were attacked by the French,