April 9/10, 1981
The spiral pattern in NGC 5645 is less
regular than in other galaxies of luminosity class
II-III on this panel. The pattern has a similar
geometrical entropy to that in NGC 428 (ScIII)
on the next panel, and hence the luminosity
classification might have been placed at III. Note,
however, that the arms are still moderately thin
in contrast to the massive arms in, say, NGC 2427
(Sc; panel 269).
The redshift of NGC 5645 is v_o = 1375 km/s.
SB(s)d (de Vaucouleurs)
Bright bar: 0.25 arcmin x 0.05 arcmin. Several knotty arms with some
Heidelberg Veroff. Vol. 9, 1926 dimensions are for the bright part only.