NGC 4833

NGC 4833
NGC 4833 is one of the over 150 globular clusters known to reside within the Milky Way.[1]
Observation data (J2000 epoch)
ClassVIII[2]
ConstellationMusca
Right ascension12h 59m 33.92s[3]
Declination–70° 52′ 35.4″[3]
Distance21.5 kly (6.6 kpc)[4]
Apparent magnitude (V)+7.79[5]
Apparent dimensions (V)13.5′
Physical characteristics
Mass4.10×105[4] M☉
Radius42 ly[6]
Metallicity = –1.71[7] dex
Estimated age12.54 Gyr[7]
Other designationsCaldwell 105, GCl 21,[5] Lacaille I.4
Dunlop 164, Bennett 56
See also: Globular cluster, List of globular clusters
The location of NGC 4833 (labelled in red)

NGC 4833 (also known as Caldwell 105) is a globular cluster discovered by Abbe Lacaille during his 1751-1752 journey to South Africa, and catalogued in 1755.[8] It was subsequently observed and catalogued by James Dunlop and Sir John Herschel whose instruments could resolve it into individual stars.

The globular cluster is situated in the very southerly constellation Musca at a distance of 21,200 light years from Earth. It is partially obscured by a dusty region of the galactic plane. After corrections for the reddening by dust, evidence was obtained that it is in the order of 2 billion years older than globular clusters M5 or M92.

  1. ^ Cite error: The named reference hstimage was invoked but never defined (see the help page).
  2. ^ Cite error: The named reference hcob849_11 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference aj140_6_1830 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference apj742_1_51 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference simbad was invoked but never defined (see the help page).
  6. ^ distance × tan( diameter_angle / 2 ) = 42 ly. radius
  7. ^ a b Cite error: The named reference mnras404_3_1203 was invoked but never defined (see the help page).
  8. ^ Jones, K. G. (March 1969). "The search for the nebulae - VI". Journal of the British Astronomical Association. 79: 213–222. Bibcode:1969JBAA...79..213J.