NGC 6604

NGC 6604
NGC 6604 and its surroundings taken by the Wide Field Imager attached to the 2.2-metre MPG/ESO telescope at the La Silla Observatory in Chile
Observation data (J2000 epoch)
Right ascension18h 18m 03.0s[1]
Declination−12° 14′ 30″[1]
Distance4,580 ly (1,403 pc)[2]
Apparent magnitude (V)6.5[3]
Physical characteristics
Estimated age6.5 Myr[1]
Other designationsNGC 6604, Cr 373, MM 23, OCl 56, C 1815-122, CTB 50, NRL 17, [KPR2004b] 439, Cl Mrk 39, LMH 24, OCISM 11[4]
Associations
ConstellationSerpens[5]
See also: Open cluster, List of open clusters

NGC 6604 is a young[6] open cluster of stars in the equatorial constellation of Serpens, positioned about 1.5° north of the Eagle Nebula (NGC 6611).[7] The cluster was discovered by William Herschel on July 15, 1784.[8] It is located at a distance of 4,580[2] light years from the Sun, about 210 ly (65 pc) above the galactic plane.[7] NGC 6604 forms the densest part of the Ser OB2 association of co-moving stars.[9]

This cluster is fairly compact with a Trumpler class of I3p,[6] and is still undergoing star formation.[10][7] It lies at the heart of an H II region with the identifier S54, and the two are most likely linked.[6] The cluster has an estimated age of 6.5[1] million years and contains several massive stars of the OB type.[6] One of these is the high mass triple star system HD 167971, which includes the over-contact eclipsing binary MY Ser. It is one of the most luminous stars in the galaxy.[10] HD 168112 is another colliding-wind binary in the cluster; both systems are over-luminous in their X-ray emission.[11]

  1. ^ a b c d Cite error: The named reference Wu_et_al_2009 was invoked but never defined (see the help page).
  2. ^ a b Cite error: The named reference Zucker_et_al_2020 was invoked but never defined (see the help page).
  3. ^ Cite error: The named reference Gilmour2012 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 eso was invoked but never defined (see the help page).
  6. ^ a b c d Cite error: The named reference Barbon_et_al_2000 was invoked but never defined (see the help page).
  7. ^ a b c Cite error: The named reference Reipurth2008 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference Seligman was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference De_Becker_et_al_2005 was invoked but never defined (see the help page).
  10. ^ a b Cite error: The named reference Ibanoglu_et_al_2013 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference De_Becker2015 was invoked but never defined (see the help page).