Messier 106

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**Messier 106**
Observation data (Epoch J2000)
Galaxy	List of galaxies
Image:M106-1.jpg M106 taken at St. Francis Xavier University
Constellation	Canes Venatici
Right ascension	12^h 18^m 57.5^s<ref name="ned" />
Declination	+47° 18′ 14″<ref name="ned" />
Redshift	448 ± 3 km/s<ref name="ned" />
Distance	23.7 ± 1.5 Mly (7.3 ± 0.5 Mpc)<ref name="tonryetal2001">J. L. Tonry, A. Dressler, J. P. Blakeslee, E. A. Ajhar, A. B. Fletcher, G. A. Luppino, M. R. Metzger, C. B. Moore (2001). "The SBF Survey of Galaxy Distances. IV. SBF Magnitudes, Colors, and Distances". Astrophysical Journal 546: 681-693.</ref>
Type	SAB(s)bc<ref name="ned">NASA/IPAC Extragalactic Database. Results for NGC 4258. Retrieved on 2006-10-18.</ref>
Apparent dimensions (V)	18′.6 × 7′.2<ref name="ned" />
Apparent magnitude (V)	+9.1<ref name="ned" />
Notable features	Maser galaxy,<ref name="Bonanos2006">Bonanos, Alceste Z. (2006). "Eclipsing Binaries: Tools for Calibrating the Extragalactic Distance Scale". Binary Stars as Critical Tools and Tests in Contemporary Astrophysics, International Astronomical Union. Symposium no. 240, held 22-25 August, 2006 in Prague, Czech Republic, S240, #008.</ref> Seyfert II galaxy<ref name="Humphreysetal2004">Humphreys, E. M. L.; Greenhill, L. J.; Reid, M. J.; Argon, A. L.; Moran, J. M. (2004). "Improved Maser Distance to NGC 4258". American Astronomical Society Meeting 205, #73.01; Bulletin of the American Astronomical Society 36: 1468.</ref>
Other designations
M106, NGC 4258, UGC 7353, PGC 39600<ref name="ned" />

Messier 106 (also known as NGC 4258) is a spiral galaxy about in the constellation Canes Venatici. It was discovered by Pierre Méchain in 1781. M106 is at a distance of about 22 to 25 million light-years away from Earth. It is also a Seyfert II galaxy, which means that due to x-rays and unusual emission lines detected, it is suspected that part of the galaxy is falling into a supermassive black hole in the center.<ref name="apod">A spiral galaxy with a strange core.</ref>

1 Characteristics
2 See also
3 External links
4 References

[edit] Characteristics

M106 has a water vapor maser that is seen by the 22GHz line of ortho-H₂O that evidences dense and warm molecular gas. Water masers are useful to observe nuclear accretion disks in active galaxies. M106 has a slightly warped, thin, almost edge-on Keplerian disk which is on a subparsec scale. It surrounds a central area with mass 4 × 10⁷M_?.<ref name="Henkeletal2005">Henkel, C.; Peck, A. B.; Tarchi, A.; Nagar, N. M.; Braatz, J. A.; Castangia, P.; Moscadelli, L. (June II 2005). "New H2O masers in Seyfert and FIR bright galaxies". Astronomy and Astrophysics 436 (1): 75-90.</ref>