April 28/29, 1979
The spiral pattern in NGC 3780 is similar
to the multiple arms in the prototype
multiple-armed galaxy M101 (Sc; Hubble Atlas,
pp. 27, 31; panel 218 here). Both galaxies are
later versions of the multiple-armed pattern of
NGC 488 (Sab; panels 115, 116, S3, S12).
The arms in NGC 3780 are thin but highly
branched. Most can be traced as individual
fragments for only about a half-rotation.
The many individual HII regions are
unresolved at the 1" level. The redshift of
NGC 3780 is v_o = 2481 km/s.
Non-interacting pair with NGC 3804 at 13.5 arcmin
SA(s)c: (de Vaucouleurs)
Paired with UGC 06640 at 13.2, 108
Small, bright nucleus. Many filamentary, knotty arms.
Non-interacting pair with NGC 3804 at 13.5 arcmin.
Ap. J., 85, 325, 1937.