Kostinskii, Sergei Konstantinovich
Born July 31 (Aug. 12), 1867, in Moscow; died Aug. 22, 1936, at Pulkovo. Soviet astronomer; specialist in photographic astrometry. Corresponding member of the Academy of Sciences of the USSR (1915).
Beginning in 1902, Kostinskii worked at the Pulkovo Observatory. One of the founders of astrophotography and photographic astrometry, he developed a new method of measuring the position of stars from photographic plates and derived formulas for the reduction of these measurements. In 1906 he discovered the phenomena of the interaction of two neighboring images on a photographic plate of close binary stars (the Kostinskii phenomenon). Kostinskii also investigated the proper motions of stars.