ABSTRACT
In 1943 Seyfert studied several galaxies characterized by bright stellar nuclei which show spectra with strong broad emission lines. A highlight of the early 1960s was the discovery of quasars and the identification of their highly redshifted spectral lines which suggested that these might be extremely luminous extragalactic objects. Systematic searches for ultraviolet-excess galaxies and emission-line galaxies have been carried out on objective prism plates taken with Schmidt telescopes. Markarian galaxies and KUGs are essentially the same since both groups are galaxies selected by the criterion that their luminosity in the blue-violet region of the wavelength is brighter than that in the yellow-red region. Many peculiar galaxies including interacting galaxies have been found on the Palomar Sky Survey prints by Vorontsov-Velyaminov and compiled in his ‘Atlas of Interacting Galaxies’.
