births
April 17, 1598
Giovanni Battista Riccioli, Italian priest and astronomer (died 1671)
Giovanni Battista Riccioli
Giovanni Battista Riccioli was an Italian astronomer and a Catholic priest in the Jesuit order. He is known, among other things, for his experiments with pendulums and with falling bodies, for his discussion of 126 arguments concerning the motion of the Earth, and for introducing the current scheme of lunar nomenclature. He is also widely known for discovering the first double star. He argued that the rotation of the Earth should reveal itself because on a rotating Earth, the ground moves at different speeds at different times.