Named in memory of Vilho Väisälä (1889–1969), a meteorologist and geophysicist, elder brother of Y. Väisälä {see planet  (2804)}. Director of the Finnish Meteorological Institute (1919–1948) and professor of meteorology at the University of Helsinki (1948–1958), he was well known for devising scientific apparatus, including a radiosonde used in many countries. (M 7949) _ _.