Named in memory of Samuil Aronovich Kaplan (1921–1978), head of the astrophysics department of the Lvov Observatory from 1948 to 1961 and subsequently a staff member of the Scientific Research Radiophysics Institute in Gorkij. He contributed extensively to a wide range of astrophysical topics, including white dwarfs, interstellar matter, radiative transfer, solar radiation, pulsars and galactic nuclei. (M 5358) _ _.