NGC 4258

NGC 4258

Messier 106
M 106 and its anomalous arms. Composite of IR (red), x-ray (blue), radio (purple) and visible light view (Image credit: NASA/CXC/University of Maryland)
Observation data (J2000 epoch)
Constellation Canes Venatici
Right ascension 12h 18m 57.5s[1]
Declination +47° 18′ 14″[1]
Redshift 448 ± 3 km/s[1]
Distance 23.7 ± 1.5 Mly (7 ± 0.5 Mpc)[2][3]
Type SAB(s)bc[1]
Apparent dimensions (V) 18′.6 × 7′.2[1]
Apparent magnitude (V) 9.1[1]
Notable features Maser galaxy,[4] Seyfert II galaxy.[5]
Other designations
M 106, NGC 4258, UGC 7353, PGC 39600.[1][6]
See also: Galaxy, List of galaxies

Messier 106 (also known as NGC 4258) is a spiral galaxy 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.[7] NGC 4217 is a possible companion galaxy of Messier 106.[6]


Characteristics

M106 has a water vapor megamaser (the equivalent of a laser operating in microwave instead of light and on a galactic scale) that is seen by the 22-GHz line of ortho-H2O that evidences dense and warm molecular gas. Water masers are useful to observe nuclear accretion disks in active galaxies. The water masers in M106 enabled the first case of a direct measurement of the distance to a galaxy and thereby providing an independent anchor for the cosmic distance ladder.[8][9] M 106 has a slightly warped, thin, almost edge-on Keplerian disc which is on a subparsec scale. It surrounds a central area with mass 4 × 107M.[10]

It's one of the largest and brightest nearby galaxies, similar in size and luminosity to the Andromeda Galaxy.[11]

See also

References

External links

  • : M106 Fact Sheet
  • Spiral Galaxy M106 at SEDS Messier pages
  • Messier 106 on Articles and images
  • NGC 4258: Mysterious Arms Revealed

, +47° 18′ 14″