NGC 3628 (a starburst galaxy), together with its neighbors M66 and M65, form a most conspicuous triplet of galaxies, the Leo Triplett or M66 group, located at a distance of about 35 million light years.
NGC 3628 is seen edge-on. This galaxy has a low level AGN with occasional x-ray flares. There is a continuous jet of neutral hydrogen issuing from the core and optical objects (quasi stellar objects) being ejected (note the trail of optical objects from lower center curving to the lower left end of the galaxy). Arp, et. al., 2002