Named in memory of Nikolaus B. Richter (1910–1980), first director of the Tautenburg Observatory (1960–1975), renowned for his experiments with meteorites and his comparative study of terrestrial particles and interplanetary matter. Author of the monograph Statistik und Physik der Kometen (1954; English edition published in 1963 under the title The nature of comets), he served as president of IAU Commission 15 during 1973–1976. He was also interested in the study of blue objects and compact galaxies. (M 10549) _ _.