Omega Centauri

Omega Centauri
The globular cluster Omega Centauri
Observation data (J2000 epoch)
ClassVIII[1]
ConstellationCentaurus
Right ascension13h 26m 47.28s[2]
Declination−47° 28′ 46.1″[2]
Distance15.8 ± 1.1 kly (4.84 ± 0.34 kpc)[3]
Apparent magnitude (V)3.9[4]
Apparent dimensions (V)36′.3[5]
Physical characteristics
Mass(4.05±0.1)×106[6] M☉
Radius86 ± 6 ly[7]
Metallicity = –1.35[8] dex
Estimated age11.52 Gyr[8]
Other designationsNGC 5139,[9] GCl 24,[9] ω Centauri,[3] Caldwell 80, Mel 118
See also: Globular cluster, List of globular clusters

Omega Centauri (ω Cen, NGC 5139, or Caldwell 80) is a globular cluster in the constellation of Centaurus that was first identified as a non-stellar object by Edmond Halley in 1677. Located at a distance of 17,090 light-years (5,240 parsecs), it is the largest known globular cluster in the Milky Way at a diameter of roughly 150 light-years.[10] It is estimated to contain approximately 10 million stars, with a total mass of 4 million solar masses,[11] making it the most massive known globular cluster in the Milky Way.

Omega Centauri is very different from most other galactic globular clusters to the extent that it is thought to have originated as the core remnant of a disrupted dwarf galaxy.[12]

  1. ^ Cite error: The named reference hcob849_11 was invoked but never defined (see the help page).
  2. ^ a b Cite error: The named reference aj140_6_1830 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference vandeVenetal2006 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference Skiff1999 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference ArnoldDohertyMoore1999 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference MNRAS429_3_1887 was invoked but never defined (see the help page).
  7. ^ distance × sin(diameter_angle / 2), using distance of 5 kpc and angle 36.3′, = 86 ± 6 ly radius
  8. ^ a b Cite error: The named reference mnras404_3_1203 was invoked but never defined (see the help page).
  9. ^ a b Cite error: The named reference simbad was invoked but never defined (see the help page).
  10. ^ "Omega Centauri: The Largest Globular Cluster". Universe for Facts. Retrieved 21 December 2014.
  11. ^ "APOD: 2010 March 31 - Millions of Stars in Omega Centauri".
  12. ^ Cite error: The named reference AJ676_2_1008 was invoked but never defined (see the help page).