Transits of Venus: 1639-2012 July 5, 2012

The Transit of Venus is both an astronomical phenomenon and a landmark in the history of American science. Transits occur in pairs eight years apart, each pair happening more than a century after the previous one. The last Transit was in June 2004. The second Transit of this pair was in June 2012. The next pair of Transits will occur in 2117 and 2125. The APS Museum will mark the 2012 Transit with several special events as well as an exhibition. This exhibition will document all observed Transits of Venus beginning in 1639 through images, rare books, and manuscripts, and will tell the story of the American Philosophical Society's role in the 1769 Transit. It will feature three 18th-century instruments used to chart that event, including the Transit telescope and astronomical clock David Rittenhouse built for himself.