Bright elliptical galaxies have a markedly different distribution of Hubble types than faint ellipticals; the division occurs near MB = −20 and bright ellipticals are rounder on average. The Hubble types of galaxies in both groups are narrowly clustered, around E1.5 in the case of the bright galaxies and around E3 for the fainter ones. The Hubble-type distribution of the faint ellipticals is consistent with oblate symmetry, but the oblate hypothesis fails for the bright ellipticals. However a distribution of triaxial intrinsic shapes can successfully reproduce the apparent shape data for either group. The distribution of intrinsic, short-to-long axis ratios is peaked around 0.75 for bright galaxies and 0.65 for faint galaxies. Our results provide further evidence that elliptical galaxies should be divided into two, morphologically distinct families. (Refer to PDF file for exact formulas).

Publication Date



Archived in: arXiv:astro-ph/9601038 v2 20 Feb 1996 AND Rutgers Astrophysics Preprint Series No. 183 This work was supported by NSF grant AST 90-16515 and NASA grant NAG 5-2803 to DM.ISSN:1538-3881 Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works in February 2014.

Document Type


Department, Program, or Center

School of Physics and Astronomy (COS)


RIT – Main Campus