NGC 3521

NGC 3521 is an intermediate spiral galaxy located in the constellation Leo.  NGC 3521 was discovered by German-British astronomer William Herschel on 22 February 1784.

Its velocity with respect to the cosmic microwave background is about 1167 km/s, which corresponds to a Hubble distance of 56.1 Mly (1 Mly = 1 Mega light-year = 1 Million light-years)

However, non-redshift measurements give a much closer distance of 37.2 Mly.

NGC 3521 is a spiral galaxy with a trace of a bar structure, a weak inner ring, and moderate to loosely wound arm structure. The bar structure is difficult to discern, both because it has a low ellipticity and the galaxy is at a high inclination of 72.7° to the line of sight. The relatively bright bulge is nearly 3/4 the size of the bar, which may indicate the former is quite massive. The nucleus of this galaxy has an ionized hydrogen (H II) - region at the core and the nucleus forms a low-ionization nuclear emission-line region.

NGC 3521 is structurally similar to the Milky Way; additionally, its supermassive black hole has a similar mass to that of the Milky Way, at about 7 million solar masses.