NGC 6166 explained

NGC 6166
Epoch:	J2000
Type:	cD2 pec.
Dist Ly:	490 Mly (142 Mpc)
Z:	z = −0.030354 (minus sign indicates blueshift)
H Radial V:	−9100 km/s
Appmag V:	12.78^[1]
Size V:	1.9’ x 1.4’
Constellation Name:	Hercules
Absmag V:	−24.1
Names:	UGC 10409, PGC 58265, CGCG 2205.6+3107 0504, MCG +07-34-060, 3C 338

NGC 6166 is an elliptical galaxy in the Abell 2199 cluster. It lies 490 million light years away in the constellation Hercules. The primary galaxy in the cluster, it is one of the most luminous galaxies known in terms of X-ray emissions.^[2]

Description

NGC 6166 is a supermassive, type cD galaxy, with several smaller galaxies within its envelope.^[3]

Suspected to have formed through a number of galaxy collisions, NGC 6166 has a large number of globular clusters (estimated as between 6,200 and 22,000 in 1996)^[4] orbiting the galaxy.^[5] A 2016 study, however, gave an even higher number (around 39,000) suggesting also that the halo of this galaxy blends smoothly with the intra-cluster medium.^[6] Because of that, the galaxy has the richest globular cluster system known.The galaxy harbors a supermassive black hole at its center with a mass of nearly 30 billion based on dynamical modelling.^[7]

NGC 6166 is known to host an active nucleus, classified as an FR I source, which powers two symmetric parsec-scale radio jets and radio lobes. These are caused by the infall of gas into its center due to a cooling flow that deposits 200 solar masses of gas every year there.^[8]

It has been proposed that a number of O-type stars may be present in the center of NGC 6166.^{[9] [10]}

See also

• List of galaxies

Notes and References

1. Web site: SIMBAD query result.
2. Bridges . T.J. . Cater . D . April 26, 1996 . B-R Colors of Globular Clusters in NGC 6166 (A2199) . The Astrophysical Journal . 281. 4 . 1290–1296 . astro-ph/9604159v1. 1996MNRAS.281.1290B . 10.1093/mnras/281.4.1290 . free . 119458738 .
3. http://ned.ipac.caltech.edu/cgi-bin/nph-datasearch?search_type=Note_id&objid=57565&objname=NGC%206166&img_stamp=YES&hconst=73.0&omegam=0.27&omegav=0.73&corr_z=1&of=table Notes for object NGC 6166 (NED)
4. Bridges . T.J. . Cater . D . April 26, 1996 . B-R Colors of Globular Clusters in NGC 6166 (A2199) . The Astrophysical Journal . 281. 4 . 3 . astro-ph/9604159v1. 1996MNRAS.281.1290B . 10.1093/mnras/281.4.1290 . free . 119458738 .
5. 1990ApJ...355..410P . A globular cluster system surrounding the cD galaxy NGC 6166 . The Astrophysical Journal . 355 . 410 . 1990 . Pritchet, C. J. . Harris, William E. . 10.1086/168774.
6. 817. 1. 17pp. Harris. William E.. Blakeslee. John P.. Whitmore. Bradley C.. Gnedin. Oleg Y.. Geisler. Douglas. Rothberg. Barry. Globular Cluster Systems in Brightest Cluster Galaxies. II. NGC 6166. The Astrophysical Journal. 2016. 2016ApJ...817...58H. 1511.08493 . 10.3847/0004-637X/817/1/58. 118501801. free.
7. Magorrian. J.. Tremaine. S.. Richstone. D.. Bender. R.. Bower. G.. Dressler. A.. Faber. S.~M.. Gebhardt. K.. Green. R.. Grillmair. C.. Kormendy. J.. Lauer. T.. The Demography of Massive Dark Objects in Galaxy Centers. The Astronomical Journal. June 1998. 115. 6. 2285–2305. 10.1086/300353. astro-ph/9708072 . 1998AJ....115.2285M . 17256372.
8. Di Matteo . Tiziana . Johnstone . Roderick M . March 8, 2001 . Accretion onto Nearby Supermassive Black Holes: Chandra Constraints on the Dominant Cluster Galaxy NGC 6166 . The Astrophysical Journal . 550 . 1 . L19 . astro-ph/0012194. 2001ApJ...550L..19D . 10.1086/319489 . 15581216 .
9. Fisher, David . Illingworth, Garth . Franx, Marijn . Kinematics of 13 brightest cluster galaxies . The Astrophysical Journal Letters . 1995 . 438 . 2 . 539–562 . 1995ApJ...438..539F . 10.1086/175100.
10. Bertola . F. . Gregg . M. D. . Gunn . J. E. . Oemler . A., Jr. . 1986-04-01 . The Stellar Population of NGC 6166 . The Astrophysical Journal . 303 . 624 . 10.1086/164111 . 1986ApJ...303..624B . 0004-637X.