Messier 106

M 106 • NGC 4258 • UGC 7353 • PGC 39600 • CGCG 244-003 • CGCG 243-067 • MCG + 08-22-104 • 2MASX J12185761 + 4718133 • VV 448 • GC 2841 • H V 43 • h 1175 •

Messier 106 or NGC 4258 is a bar-spiral galaxy with dimensions 18 ′, 6 × 7 ′, 2 and an apparent magnitude of 8.3 mag in the constellation Canes Venatici .

M106 is a galaxy that is assigned the type Sbp in the Hubble sequence , where the p stands for peculiar , d. H. peculiarly . Some authors also indicate the type with SABbc, i.e. between normal spiral and bar spiral . At a distance of about 23 million light years , the galaxy lies in the vicinity of several galaxy groups, as a member of which the galaxy is listed depending on the author, for example the Ursa Major group , the Coma Sculptor group , the Canes Venatici-I -Group or the Canes Venatici II group . The galaxy is about 135,000 light years in diameter.

The core of the galaxy has been active and known as a radio source since the 1950s. In 1995, Brent Tully et al. Described that the center ejects a jet that should be related to the massive central object of this galaxy discovered that same year. This central object is presumably a black hole of almost 40 million solar masses. In its environment, astrophysicists observe an emission line spectrum to which the galaxy core owes its classification as a LINER type (Low Ionization Nuclear Emission-line Region).

The two spiral arms are characterized by large numbers of young, massive stars that shine in a bluish light. The galaxy is currently going through a so-called » starburst «, in which the star formation rate is greatly increased.

The object was discovered by Pierre Méchain in July 1781 .