Väisälä is a tiny lunarimpact crater located on a rise in the Oceanus Procellarum. Sharing the same continental island are the brilliant crater Aristarchus to the south-southeast and Herodotus to the south-southwest. Väisälä lies just to the west of the Rupes Toscanelli fault line, and the Rimae Aristarchus rille system. To the southwest is the notable Vallis Schröteri cleft.
This formation is circular and cup-shaped, with a higher albedo than the surrounding dark surface. It was previously designated Aristarchus A before being named after prolific Finnish astronomer Yrjö Väisälä by the IAU in 1973.[1]
Menzel, D. H.; Minnaert, M.; Levin, B.; Dollfus, A.; Bell, B. (1971). "Report on Lunar Nomenclature by the Working Group of Commission 17 of the IAU". Space Science Reviews. 12 (2): 136–186. Bibcode:1971SSRv...12..136M. doi:10.1007/BF00171763. S2CID122125855.