Asteroid rotation - Hunting for a record: 1689 Floris-Jan

Last year, in June 1981 - ESO Messenger No. 24, p. 22-23 - H. J. Schober published areport on "Spinning Asteroids and Photometry". There he mainly gave a general introduction about what can be done using UBV photometry in order to derive physical properties of asteroids such as geometrie forms, diameters, reflectance on the surface, bimodality of asteroids with respect to typology. A special effort was made to report about the activities to deal with asteroids as "variable objects" like variable stars - showing Iightcurves with defined rotation rates to be derived. Among asteroids it was stated that the longest rotation periods found before 1975 were not larger than 20 hours - followed by 654 Zelinda 31 ~9 (1975). 393 Lampetia 38h7, 128 Nemesis 39h0 (1979), 709 Fringilla 52h4 (1979) and 182 Eisa 80~00 (1980), the latter corresponding to 3d33.