Sidney van den Bergh
Sidney van den Bergh ( born May 20, 1929 in Wassenaar in the Netherlands ) is a Canadian astronomer.
Van den Bergh studied at Leiden University and Princeton University where he earned a Bachelor degree. The master he graduated from the Ohio State University and his doctorate in 1956 at the University of Göttingen. After two years at Ohio State University, he was 19 years at the University of Toronto. Since 1978 he worked at the Dominion Astrophysical Observatory in Victoria, he served as director until 1986 and he remained connected even after his retirement in 1998.
Van den Bergh contributed to many areas of observational astronomy. At the David Dunlap Observatory of the University of Toronto, he led the DDO classification schema by divided the galaxies into luminosity classes from I to V: I = supergiant galaxies, II = bright giant galaxies, III = giant galaxies, IV = subgiant and V = dwarf galaxies. He was a major participant in the discussions of the 1970s to the 1990s about the correct value of the Hubble constant.