NGC 6530

Source: Wikipedia, the free encyclopedia.
NGC 6530
′[5]
Physical characteristics
Radius7 ly[6]
Estimated age4–6 Myr[7]
H II region
Other designationsCr 362
Associations
ConstellationSagittarius
See also: Open cluster, List of open clusters

NGC 6530 is a young

′.[5] The nebulosity was first discovered by G. B. Hodierna prior to 1654, then re-discovered by J. Flamsteed circa 1680. It was P. Loys who classified it as a cluster in 1746, as he could only resolve stars. The following year, G. Le Gentil determined it was both a nebula and a cluster.[10]

Portion of NGC 6530 seen by Hubble

The brightest six members of the cluster are visible in 10×50 binoculars at magnitudes 6.9 and fainter, while fifteen evenly distributed stars are visible with a 25×100 pair.

interstellar dust along the line of sight from the Earth is 1.20±0.24, with a color excess E(B−V) of 0.38±0.07.[8]

In total, 3,675 stars in the field of NGC 6530 have been catalogued as candidate members, with the likely members being 2,728.

near infrared emission excess, while the remainder are weak T Tauri stars showing a photospheric excess.[9] Candidate stars appear in two main groups at the cluster core and the Sagittarius "Hourglass nebula", with other smaller concentrations. Two such minor concentrations are associated with the stars 7 Sgr and HD 164536.[3]

Age estimates for the members shows a spread in values that suggests more than one burst of

gravitationally unbound and there is evidence the star population is expanding, particularly to the north and south.[12]

References

  1. ^
    S2CID 6066790
    .
  2. S2CID 119328315
    .
  3. ^
    S2CID 119428764
    . A25.
  4. ^ "NGC 6530". SEDS NGC Catalog. Archived from the original on 27 September 2021. Retrieved 27 April 2022.
  5. ^
    S2CID 118422539
    .
  6. ^
    ISBN 9781108457569
    .
  7. S2CID 59375851
    . A30.
  8. ^
    doi:10.1088/1538-3873/ab6aba
    . 044301.
  9. ^
    S2CID 119394685
    . A159.
  10. ISBN 9783319188720
    .
  11. ISBN 9783709106266
    .
  12. doi:10.1093/mnras/stz870
    .

External links
Retrieved from "https://en.wikipedia.org/w/index.php?title=NGC_6530&oldid=1205939787"