5.5. The K-System
This is the most numerous group of all and comprises 23 galaxies having a great diversity in appearance. Their spectra, however, indicate that the principal contribution to the total luminosity in the blue-violet region is probably from K-type giant stars. The K-systems are listed in Table V, and they all have one property in common: the major part of the luminosity originates in a brilliant, amorphous central region.
|224 (M 31)||Sb||4111||S0||4649 (M 60)||E2|
|2950||SB0||4486 (M 87)||E0||5308||S0|
|3031 (M 81)||Sb||4565||Sb||5363||Irr|
The forms of the K-systems fall into several well-defined groups: (1) the great Sb and Sa spiral systems; (2) barred spirals of strong central concentration of light; (3) the giant elliptical systems; (4) "dustless" systems similar in figure to the Sa-Sb spirals; (5) nondescript systems.