Named in memory of Kalle Väisälä (1893–1968), an algebraist and number theorist, younger brother of Y. Väisälä {see planet  (2804)}. Author of various textbooks for secondary school and university, he was professor of mathematics at Tartu University during 1919–1922, at the University of Turku during 1922–1938, and at the Helsinki Technological University during 1939–1960. (M 7949) _ _.