M65 (NGC 3623), M66 (NGC 3627), and NGC 3628 (also known as Leo Triplet), spiral galaxies type SAB(rs)a, SAB(s)b and SAb pec accordingly

Cross-identifications:

M65: NGC 3623, Arp 317B, LEDA 34612, MCG+02-29-018, UGC 6328, Messier 65

M66: NGC 3627, Arp 317A, Arp 16, Ark 288, LEDA 34695, MCG+02-29-019, UGC 6346, VV 308a, VV 308, Messier 66

NGC 3628: Arp 317C, LEDA 34697, MCG+02-29-020, UGC 6350

M65, M66 and NGC 3628 are known as Leo Triplet, a well known conspicuous grouping of galaxies (also known as the M66 Group). This is a small group of galaxies about 35 million light-years away in the constellation Leo. Halton Arp includes these galaxies in his entry number 317 (A,B,C) of his Catalogue of Peculiar Galaxies. These galaxies are physically and dynamically related. The distance between M65 and M66 is only 160 000 light years.

M66 shows some disturbed features believed to be related to the remote encounter. It's spiral arms are deformed, and they seem to be distorted and displaced above the plane of the galaxy. M66 is considerably larger than its neighbor M65 and has a well developed but not well defined central bulge. In spiral arms can be seen much dust and a few pink nebulae, signs of star formation. M65 looks like a very "normal" Sa type spiral and seems to have felt little influence. It has a prominent central lens and tightly wound spiral arms, and a lane of dust in left-side edge of the galaxy. The luminous disk is dominated by a smooth old stellar population. Near the lane, some knots are visible, which, may be associated with star forming regions.

Charts and image details obtained from Astrometry.net

Image and FOV details

RC 16" Astrograph (IRIDA South dome)

Imaging details