NGC 6755

NGC 6755
NGC 6755 (taken from Stellarium)
Observation data (J2000 epoch)
Right ascension19h 07m 46.1s[1]
Declination+04° 13′ 26″[1]
Distance8,060 ly (2,471.2 pc)[1]
Apparent magnitude (V)7.5[2]
Apparent dimensions (V)15'[2]
Physical characteristics
Estimated age250 Myr[3]
Other designationsNGC 6755, Cr 397[4]
Associations
ConstellationAquila
See also: Open cluster, List of open clusters

NGC 6755 is an open cluster of stars in the equatorial constellation of Aquila, positioned about 3° to the east of the star Delta Aquilae.[2] It was discovered by the Anglo-German astronomer William Herschel on July 30, 1785[5] and is located at a distance of 8,060 light years from the Sun.[1] NGC 6756 lies 30′ to the northeast of NGC 6755, with the pair forming a visual double cluster. However, they probably do not form a binary cluster system since they have different ages and are too distant from each other.[2]

This cluster has a Trumpler class of II2r with a visual magnitude of 7.5 and it spans an angular size 15′.[2] It has an estimated age of 250 million years, based on the main sequence turnoff.[3] A total of 71 variable stars have been detected in the field of this cluster, of which 31 are eclipsing binaries, seven are pulsating variables, and 28 are most likely irregular variable red giants.[6]

  1. ^ a b c d Cite error: The named reference Cantat-Gaudin_Anders_2020 was invoked but never defined (see the help page).
  2. ^ a b c d e Cite error: The named reference O'Meara2011 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference Kjeldsen_Frandsen_1991 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 Seligman was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference Ciechanowska_et_al_2007 was invoked but never defined (see the help page).