Good Chappe; August 2012; Scientific American Magazine; by Steve Mirsky; 1 Page(s)

As the 2012 transit of Venus rolled around, I got caught up in the excitement. Which led me to read The Day the World Discovered the Sun, a new account of the arduous attempts by the scientific community to observe the two Venus transits of the 1760s. (My ensuing audio interviews with author Mark Anderson are archived at www.ScientificAmerican.com/podcast.)

Until I read the book, I never knew how much I had in common with 18th-century French astronomer Jean-Baptiste Chappe d'Auteroche. Well, we had one big thing in common. In 1769 he traveled to the Sea of Cortez, between the Baja peninsula and mainland Mexico, to observe the transit. His data collection, combined with those of other sky watchers at different latitudes, would enable astronomers to calculate the distance from Earth to Venus and the sun. In 1991 I went to the same location, which lay in the narrow band that would experience another spectacular astronomical event, a total eclipse of the sun.