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
Venus In Situ Explorer 4 to be launched in 2024. Of the 12 proposals submitted and reviewed by NASA, three were associated with this theme: two lander proposals, Venus In situ Composition Investigations (VICI) and Venus In Situ Atmospheric and Geochemical Explorer (VISAGE); and the Venus Origins Explorer (VOX), an orbiter whose proponents claimed would achieve similar scientific outcomes. None of the three advanced to the final shortlist. Venus In Situ Explorer The Venus In Situ Explorer (VISE) has been a lander mission concept proposed since 2003 by the Planetary Science Decadal Survey as a space probe designed to answer fundamental scientific questions by