NGC 6284

NGC 6284
NGC 6284 as seen through the Hubble Space Telescope
Observation data (J2000 epoch)
ClassIX
ConstellationOphiuchus
Right ascension17h 04m 28.747s
Declination−24° 45′ 51.22″
Distance43,000 ly (13,200 pc)
Apparent magnitude (V)7.43
Apparent dimensions (V)6.2' × 6.2'
Physical characteristics
Metallicity[Fe/H] = −1.26 dex
Estimated age13.3~ billion years
Other designationsGCl 53, 2MASX J17042874-2445512
See also: Globular cluster, List of globular clusters

NGC 6284 is a globular cluster located in the constellation Ophiuchus. It is designated as IX in the galaxy morphological classification scheme and was discovered by the German-born British astronomer William Herschel on 22 May 1784. Its distance had previously been estimated at 49,900 light years from Earth, but this was revised in 2023 to around 43,000 light years. This same study, based on high-resolution Hubble Space Telescope optical observations, produced the first high-quality colour-magnitude diagram (CMD) of NGC 6284, extending down to about six magnitudes below its main sequence turn-off. The new observations moved its centre of gravity by 1.5–3 arcseconds from previous values, and its density profile showed a steep central cusp, suggesting that NGC 6284 is a post-core collapse (PCC) cluster.

The nearby metal-poor star HD 194598 [es] may be a recent runaway from NGC 6284.

See also

References

  1. 1 2 3 4 "NGC 6284". SIMBAD. Centre de données astronomiques de Strasbourg.
  2. 1 2 3 "Globular cluster NGC 6284 inspected by astronomers".
  3. 1 2 "Revised NGC Data for NGC 6284". Seds. Retrieved 3 October 2015.
  4. ↑ William E. Harris. "Catalog of Parameters for Milky Way Globular Clusters". Retrieved 3 February 2017.
  5. ↑ "Object No. 1 – NGC 6284". NASA/IPAC extragalactic database. NASA/IPAC. Retrieved 3 October 2015.
  6. ↑ "NGC 6284 (= GCL 53)". cseligman. Retrieved 3 October 2015.
  7. ↑ "NGC 6284". Seds. Retrieved 3 October 2015.
  8. ↑ "The globular cluster NGC 6284". In-the-sky. Retrieved 3 October 2015.
  9. ↑ Şahin, Timur; Bilir, Selçuk (2020), "On the Origin of Metal-poor Stars in the Solar Neighborhood", The Astrophysical Journal, 899 (1): 41, arXiv:2007.08514, Bibcode:2020ApJ...899...41S, doi:10.3847/1538-4357/aba2d2, S2CID 220545932