1982/06/01 by R. Brent Tully · 5 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Stellar, planetary, and galactic studies #Galaxies: Formation, Evolution, Phenomena
paper · doi:10.1086/159999
openalex publication_date 1982/06/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/06/09
It is argued that the Local Supercluster (LS) consists of two distinct components: a disk component with 60% of the luminous galaxies, and a halo component with 40% of the luminous galaxies. In regard to the halo component, almost all the luminous galaxies are associated with only a small number of clouds; hence, most of the volume off the disk of the LS is empty. The clouds in the halo are sufficiently separated from the disk so that the two-component distinction seems warranted, and at least the more prominent clouds in the halo seem to be prolate structures with their long axes directed toward the Virgo Cluster. In regard to the disk component, the ratio of the longest to the shortest axis is 6 to 1 (practically independent of velocity effects), and the absolute rms dimension of the short axis is + or - 1.1/h Mpc (h = H0/100 km/s-Mpc). If velocities normal to the plane of the LS are very low, the implication is that the disk was formed through dissipative processes.