A type Sa spiral galaxy in the constellation Virgo whose unusually large central bulge, richly populated with several hundred globular clusters, and dark prominent dust lanes give it the appearance of a Mexican hat; we see it from about 6° south of its equatorial plane. Discovered by Pierre Méchain in 1781, it became the first galaxy for which a large redshift (equivalent to a recession velocity of about 1,000 km/s) was found, by Vesto Slipher in 1912. It is also the first galaxy in which rotation was detected, again by Slipher. Modern studies have shown the Sombrero to have both a very extended faint halo and a mildly active nucleus indicative of the presence a central supermassive black hole.
