On 18 February 1679 Paris Observatory astronomer Jean Dominique Cassini presented a new map of the Moon to the Academy of Sciences in Paris, and this then became the standard reference work for French astronomers who carried out selenographical observations. Among these was a contingent of Jesuit missionaryastronomers who sailed from Brest on 3 March 1685, bound for China. En route they were forced to spend some months in Siam (present-day Thailand) and used the map when they observed the lunar eclipse of 11 December 1685. In this paper we examine the creation of the 1679 Moon map and its use by the French Jesuit missionaryastronomers in Siam in 1685.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.