Template:Selected anniversaries/April 17
1598: Priest and astromomer Giovanni Battista Riccioli born. Riccioli will experiment with pendulums and falling bodies, discuss arguments concerning the motion of the Earth, and introduce the current scheme of lunar nomenclature.
1938: Philosopher and author Kerry Wendell Thornley born. Thornley will write a manuscript, The Idle Warriors, about his acquaintence Lee Harvey Oswald.
1961: Bay of Pigs Invasion: A group of Cuban exiles financed and trained by the CIA lands at the Bay of Pigs in Cuba with the aim of ousting Fidel Castro.
1969: Sirhan Sirhan is convicted of assassinating Robert F. Kennedy.
1996: Mathematician, author, and poet Piet Hein dies. Hein proposed the use of superellipses in architecture; superellipses subsequently became the hallmark of modern Scandinavian architecture.