Astronomy:NGC 6834

From HandWiki
Short description: Open cluster in the constellation Cygnus
NGC 6834
Ngc 6834.jpg
Observation data (J2000.0 epoch)
ConstellationCygnus
Right ascension 19h 52m 12.5s[1]
Declination+29° 24′ 29″[1]
Distance10,850 ly (3,326.7 pc)[2]
Apparent magnitude (V)7.8[3]
Apparent dimensions (V)12[2]
Physical characteristics
Radius6.1 ly
Estimated age65±18 Myr[4]
Other designationsNGC 6834, C 1950+292[5]
See also: Open cluster, List of open clusters

NGC 6834 is a young[6] open cluster of stars located about 10,850[2] light years from the Sun in the constellation Cygnus. It was discovered on July 17, 1784, by Anglo-German astronomer William Herschel.[7] The cluster has a visual magnitude of 7.8, which is dimmed by 2.1 magnitudes due to interstellar dust.[3] Half the cluster members lie within an angular radius of 6′.[2]

The Trumpler class of this cluster is II 2 m, indicating it is medium-rich in stars (m) with a moderate brightness range (2) and little central concentration of the stars (II).[6] It has about 260 members[2] and an age of approximately 65 million years,[4] although estimates range from 50 to 80 million.[6] A total of fifteen B-type variable stars have been detected in the cluster with four Be stars. Five of the cluster members show hydrogen alpha emission, including a γ Cas and two λ Eri variables.[6]

References

  1. 1.0 1.1 Kerber, F. et al. (September 2003). "Galactic Planetary Nebulae and their central stars. I. An accurate and homogeneous set of coordinates". Astronomy and Astrophysics 408 (3): 1029–1035. doi:10.1051/0004-6361:20031046. Bibcode2003A&A...408.1029K. 
  2. 2.0 2.1 2.2 2.3 2.4 Cantat-Gaudin, T.; Anders, F. (January 2020). "Clusters and mirages: cataloguing stellar aggregates in the Milky Way". Astronomy & Astrophysics 633: 22. doi:10.1051/0004-6361/201936691. A99. Bibcode2020A&A...633A..99C. 
  3. 3.0 3.1 Crossen, Craig; Rhemann, Gerald (2012). Sky Vistas: Astronomy for Binoculars and Richest-Field Telescopes. Springer Vienna. p. 68. ISBN 9783709106266. https://books.google.com/books?id=3vELBwAAQBAJ&pg=PA68. 
  4. 4.0 4.1 Paunzen, E.; Netopil, M. (October 2006). "On the current status of open-cluster parameters". Monthly Notices of the Royal Astronomical Society 371 (4): 1641–1647. doi:10.1111/j.1365-2966.2006.10783.x. Bibcode2006MNRAS.371.1641P. 
  5. "NGC 6834". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=NGC+6834. 
  6. 6.0 6.1 6.2 6.3 Mathew, Blesson et al. (September 2014). "Optical/IR studies of Be stars in NGC 6834 with emphasis on two specific stars". Research in Astronomy and Astrophysics 14 (9): 1173–1192. doi:10.1088/1674-4527/14/9/008. 1173-1192. Bibcode2014RAA....14.1173M. 
  7. Seligman, Courtney. "NGC Objects: NGC 6800 - 6849". Celestial Atlas. https://cseligman.com/text/atlas/ngc68.htm#6834. 

External links