NGC 6250

NGC 6250
Observation data (J2000 epoch)
Right ascension16h 57m 58.(0)s[1]
Declination−45° 56′ 3(6)″[1]
Distance2,820 ly (865 pc)[1]
Apparent magnitude (V)5.9[2]
Apparent dimensions (V)18′[2]
Physical characteristics
Estimated age14 Ma[3]
Other designationsNGC 6250, Cr 320, C 1654-457, ESO 277-SC20, OCL 991, VDBH 206.[4]
Associations
ConstellationAra
See also: Open cluster, List of open clusters

NGC 6250 is a open cluster of stars in the southern constellation of Ara, near the border with Scorpius.[5] It was discovered by English astronomer John Herschel on July 1, 1834.[6] This cluster has an apparent visual magnitude of 5.9 and spans an angular diameter of 18′,[2] with the brightest member being of magnitude 7.6. About 15 members are visible with binoculars or a small telescope.[7] NGC 6250 is located at a distance of 2,820 ly (865 pc) from the Sun,[1] and is approaching with a mean radial velocity of −10±6 km/s.[8]

The Trumpler classification of NGC 6250 is II 3 r, indicating a rich cluster of stars (r) with a slightly disparate grouping (II) and a large brightness range (3).[9] This is a young cluster with an estimated age of 14 million years.[3] Seven cluster members are B-type stars,[10] and three are illuminating reflection nebulae.[11] Two magnetic chemically peculiar stars (CP2) and two candidate Lambda Boötis stars have been identified as members.[9] The metallicity of the cluster members is consistent with the Sun.[8]

  1. ^ a b c d Cite error: The named reference aa376_441 was invoked but never defined (see the help page).
  2. ^ a b c Cite error: The named reference Inglis2013 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference mnras391_1_447 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference Harrington_1990 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference cseligman was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference Simpson_2012 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference Martin_et_al_2017 was invoked but never defined (see the help page).
  9. ^ a b Cite error: The named reference Bayer_et_al_2000 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference McSwain_Gies_2005 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Herbst_1977 was invoked but never defined (see the help page).