NGC 7790

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NGC 7790
NGC 7790.png
NGC 7790 (taken from Stellarium)
Credit: Roberto Mura
Observation data (J2000.0 epoch)
Constellation Cassiopeia
Right ascension 23h 58m 24.2s[1]
Declination +61° 12′ 30″[1]
Distance 10.76 ± 0.75 kly (3.30 ± 0.23 kpc)[2]
Apparent magnitude (V) 8.5
Apparent dimensions (V) 7′.4[2] diameter
Physical characteristics
Estimated age 60–80[3] Myr
See also: Open cluster, List of open clusters

NGC 7790 is a young open cluster[1] of stars located some 10,800[2] light years away from Earth in the northern constellation of Cassiopeia. At this distance, the light from the cluster has undergone extinction from interstellar gas and dust equal to E(B – V ) = 0.51 magnitude in the UBV photometric system. NGC 7790 has a Trumpler class rating of II2m[2] and the estimated age is 60–80 million years.[3] It contains three cepheid variables: CEa Cas, CEb Cas, and CF Cas.[2]

This cluster is on an orbit through the Milky Way galaxy that has an eccentricity of 0.22 ± 0.07 and a period of (225.0 ± 27.1) million years. It will come as close as 20.2 ± 3.9 kly (6.2 ± 1.2 kpc) to, and as distant as 31.6 ± 2.9 kly (9.7 ± 0.9 kpc) from, the Galactic Center. The maximum distance reached above (or below) the galactic plane is 0.78 ± 1.30 kly (0.24 ± 0.40 kpc). On average, it will cross the galactic plane every (35.7 ± 13.0) million years.[4]

References[edit]

  1. ^ a b c Revised New General Catalogue and Index Catalogue, Wolfgang Steinicke, February 2009, retrieved 2013-07-01.  External link in |publisher= (help)
  2. ^ a b c d e Gupta, A. C.; et al. (September 2000), "A complete photometric study of the open cluster NGC 7790 containing Cepheid variables", Astronomy and Astrophysics Supplement, 145: 365–375, Bibcode:2000A&AS..145..365G, doi:10.1051/aas:2000247. 
  3. ^ a b Davidge, T. J. (December 2012), "The Young Open Clusters King 12, NGC 7788, and NGC 7790: Pre-main-sequence Stars and Extended Stellar Halos", The Astrophysical Journal, 761 (2): 155, Bibcode:2012ApJ...761..155D, arXiv:1211.6398Freely accessible, doi:10.1088/0004-637X/761/2/155. 
  4. ^ Wu, Zhen-Yu; et al. (November 2009), "The orbits of open clusters in the Galaxy", Monthly Notices of the Royal Astronomical Society, 399 (4): 2146–2164, Bibcode:2009MNRAS.399.2146W, arXiv:0909.3737Freely accessible, doi:10.1111/j.1365-2966.2009.15416.x. 

External links[edit]

Coordinates: Sky map 23h 58m 24.2s, +61° 12′ 30″

Map Showing Location of NGC 7790 (Roberto Mura)