MASSES OF GALAXIES AND GREATEST REDSHIFTS OF QUASARS

The outer parts of a typical galaxy follows an R-2 density distribution which results in the collapse time of its protogalaxy being proportional to its mass. Since quasars probably occur in the nuclei of galaxies which can only form after the collapse of their parent galaxies, their greatest observed redshift, Zmax, is largely determined by the mass, Mt, of a typical protogalaxy. The observed Zmax of quasars indicates that Mt=1 × 1012Mo. This mass is consistent with the masses of galaxies found in recent dynamical studies. It indicates that most of the mass in a typical galaxy is in the halo lying beyond the familiar optically-bright core, but the mass of a standard galaxy is still only 0.3 of that required for galaxies alone to close the universe. © 1977 Royal Astronomical Society.