Some Properties of Normal Galaxies
•                          S & SB             Elliptical         Irregular
•                                   galaxies             galaxies          galaxies
•
•Mass (M¤)                 109 – 4x1011         105- 1013        108- 3x 1010
•
•Luminosity (L¤)          108- 2x1010       3x 105 – 1011       107 - 109 
•
•Diameter (kpc)             5-250                1-200                1-10
•
•
•% of observed                77%                  20%                  3%
•galaxies
•
•Hubble could be sequence in rotation properties
•ellipticals display little internal rotation – no disk
•Sa, SBa – sufficient rotation to form disk but bulge dominates