| NGC 5286 | |
|---|---|
 NGC 5286 imaged by theHubble Space Telescope | |
| Observation data (J2000epoch) | |
| Class | V[1] |
| Constellation | Centaurus |
| Right ascension | 13h 46m 26.81s[2] |
| Declination | –51° 22′ 27.3″[2] |
| Distance | 35.9 kly (11.0 kpc)[3] |
| Apparent magnitude (V) | 7.6 |
| Apparent dimensions (V) | 9.1' |
| Physical characteristics | |
| Mass | 7.13×105[4] M☉ |
| Metallicity | [Fe/H] = –1.41[5]dex |
| Estimated age | 12.54 Gyr[5] |
| Other designations | Caldwell 84 |
| See also:Globular cluster,List of globular clusters | |
NGC 5286 (also known asCaldwell 84) is aglobular cluster ofstars located some 35,900[3]light years away in theconstellationCentaurus. At this distance, the light from the cluster has undergonereddening from interstellar gas and dust equal toE(B – V) = 0.24magnitude in theUBV photometric system. The cluster lies 4arc-minutes north of the naked-eye starM Centauri.[6] It was discovered by Scottish astronomerJames Dunlop, active in Australia, and listed in his 1827 catalog.[7]
This cluster is about 29 kly (8.9 kpc) from theGalactic Center and is currently orbiting in theMilky Wayhalo. It may be associated with theMonoceros Ring—a long tidal stream of stars that could have been formed from a disrupteddwarf galaxy. NGC 5286 may be one of the oldest globular clusters in the galaxy,[6] with an estimated age of 12.54 billion years.[5] It is not perfectly spherical, but has a projectedellipticity of 0.12.[6]
Thevelocity dispersion of stars at the center of the cluster is(8.1 ± 1.0)km/s. Based upon the motions of stars at the core of this cluster, it may host anintermediate mass black hole with less than 1% of the cluster's mass. The upper limit for the mass estimate of this object is 6,000 times themass of the Sun.[6]
NGC 5286 is part of theGaia Sausage, the hypothesised remains of a merged dwarf galaxy.[8]
{{cite journal}}: CS1 maint: multiple names: authors list (link)
Media related toNGC 5286 at Wikimedia Commons
