






Astro*Dictionary by Michael Erlewine
1 article for "Picard, Jean"
Picard, Jean [Astro*Index](pee-kahr') (1620-1682) French astronomer and Roman Catholic priest. Born at la Fleche, Sarthe; died at Paris.
Professor of astronomy at the College de France, charter member of the French Academy of Sciences, he helped to found the Paris Observatory. First to use the telescope for measurement of small angles, he derived an improved value for the circumference of the earth, using the method Eratosthenes, but with observations of a star instead of the Sun. His value of 24,876 miles (radius of 3950 miles), allowed Newton to correctly determine the Moon's motion.
See also:
♦ Newton, Sir Isaac
Astro*Index Copyright © 1997 Michael Erlewine