HD 193322 (HR 7767) is a group of six stars which appear to be at least loosely bound into a system in the constellation Cygnus.[6] The stars comprise the core of the young open cluster Collinder 419 (Cr 419), which contains a total of 51 known stars.[8] Another prominent member of the cluster is the eclipsing binary star V470 Cygni [mk] (HD 228911). The cluster lies at a distance of about 3500 light years and its stars are only a few million years old.

HD 193322
Location of HD 193322 (circled)
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Cygnus
HD 193322A
Right ascension 20h 18m 06.9877s[1]
Declination +40° 43′ 55.4947″[1]
Apparent magnitude (V) +5.958[1]
HD 193322B
Right ascension 20h 18m 06.7684s[2]
Declination +40° 43′ 54.3586″[2]
Apparent magnitude (V) +8.23[2]
Characteristics
HD 193322Aa
Evolutionary stage main-sequence star
Spectral type O9Vnn[3]
HD 193322Ab1
Evolutionary stage giant star
Spectral type O8.5 III[3]
HD 193322Ab2
Evolutionary stage main-sequence star
Spectral type B2.5 V?[3]
HD 193322B
Evolutionary stage main-sequence star
Spectral type B1.5 V[2]
HD 193322C
Evolutionary stage main-sequence star
Spectral type B8 V[3]
HD 193322D
Evolutionary stage main-sequence star
Spectral type B9 V[3]
Astrometry
HD 193322A
Proper motion (μ) RA: -2.488[4] mas/yr
Dec.: -6.837[4] mas/yr
Parallax (π)1.0669 ± 0.1403 mas[4]
Distanceapprox. 3,100 ly
(approx. 900 pc)
HD 193322B
Proper motion (μ) RA: -3.070[5] mas/yr
Dec.: -6.015[5] mas/yr
Parallax (π)0.9268 ± 0.0432 mas[5]
Distance3,500 ± 200 ly
(1,080 ± 50 pc)
Orbit[6]
PrimaryHD 193322Aa
CompanionHD 193322Ab
Period (P)44±1 yr
Semi-major axis (a)0.0525+0.0025
−0.0020
Eccentricity (e)0.58+0.03
−0.04
Inclination (i)37+6
−4
°
Details[3]
HD 193322A
MassAa: 21 M
Ab1: 23 M
Ab2: 9 M
Surface gravity (log g)Aa: 4.0 cgs
Ab1: 3.5 cgs
Ab2: 4.0 cgs
TemperatureAa: 33,000 K
Ab1: 32,500 K
Ab2: 20,000 K
Rotational velocity (v sin i)Aa: 350 km/s
Ab1: 40 km/s
Ab2: 200 km/s
Age7[7] Myr
HD 193322B
Surface gravity (log g)4.0 cgs
Temperature23,000 K
Rotational velocity (v sin i)100 km/s
Other designations
HR 7767, CP+40 4103, GC 28228, 2MASS J20180697+4043554
HD 193322A: TYC 3155-2321-1, Gaia EDR3 2062360626011542272 304.5291012654289
HD 193322B: TYC 3155-2321-2, Gaia EDR3 2062360626009209856
HD 193322C: UCAC2 46029301, 2MASS J20180562+4043248, Gaia EDR3 2062359152847218432
HD 193322D: UCAC2 46029306, 2MASS J20180691+4043055, Gaia EDR3 2062359084127740032
Database references
SIMBADdata
data2
data3
data4
data5

System

edit
HD 193322
A
 

Aa

Ab

Ab1

Ab2

         
 
  

B

 
  

C

  
  

D

HD 193322A

edit
 
The γ Cygni region of Cygnus. HD 193322 is the blue star above and right of γ Cygni (annotated in full-size image).

The brightest and most massive component, HD 193322A, is a triple star system and emits 89% of the system's visible light. It is composed of Aa and Ab on an eccentric 44-year orbit. The binary Ab itself consists of stars Ab1 and Ab2 on a 311.03±0.25 d orbit.[9] The total mass of the system HD193233A has been calculated to be 76.1+9.9
−7.4
 M
,[6] although the individual stellar masses give a smaller total.[3]

HD 193222Aa has spectral class O9Vnn, indicating a main-sequence star with highly-broadened absorption lines due to rapid rotation. HD 193322Ab1 has spectral class O8.5III, although its derived physical properties suggest it may actually be on the main sequence. Its companion HD 193322Ab2 is a main-sequence star of spectral class B2.5. The Ab pair may have a combined mass and brightness greater than Aa.[3]

HD 193322B

edit

HD 193322B is a single B-type main-sequence star separated from HD 193322A by 2.76 arcseconds on the sky, which puts them at least 2,780 astronomical units (AU) apart. Making several assumptions, the orbital period would be about 11 thousand years. HD 193322B produces 11% of the visible light emitted by the six-star system.[3]

Other components

edit

The components HD 193322C and HD 193322D are late B-class main sequence stars, respectively 34 and 50″ from the central star. It is unclear if the two are gravitationally bound to the system.[9] HD 193322D is a suspected Lambda Boötis star.[10]

References

edit
  1. ^ a b c "HD 193322A", SIMBAD, Centre de données astronomiques de Strasbourg
  2. ^ a b c d "HD 193322B", SIMBAD, Centre de données astronomiques de Strasbourg
  3. ^ a b c d e f g h i Ten Brummelaar, Theo A.; O'Brien, David P.; Mason, Brian D.; Farrington, Christopher D.; Fullerton, Alexander W.; Gies, Douglas R.; Grundstrom, Erika D.; Harkopf, William I.; Matson, Rachel A.; McAlister, Harold A.; Virginia Mcswain, M.; Roberts, Lewis C.; Schaefer, Gail H.; Simón-Díaz, Sergio; Sturmann, Judit; Sturmann, Laszlo; Turner, Nils H.; Williams, Stephen J. (2011), "An Interferometric and Spectroscopic Analysis of the Multiple Star System Hd 193322", The Astronomical Journal, 142 (1): 21, arXiv:1104.4810, Bibcode:2011AJ....142...21T, doi:10.1088/0004-6256/142/1/21, S2CID 17007212
  4. ^ a b c Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
  5. ^ a b c Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
  6. ^ a b c Maíz Apellániz, J. (2019), "Gaia DR2 distances to Collinder 419 and NGC 2264 and new astrometric orbits for HD 193 322 Aa,Ab and 15 Mon Aa,Ab", Astronomy & Astrophysics, 630: A119, arXiv:1908.02040, Bibcode:2019A&A...630A.119M, doi:10.1051/0004-6361/201935885, S2CID 199452805
  7. ^ Roberts, Lewis C.; Gies, Douglas R.; Parks, J. Robert; Grundstrom, Erika D.; McSwain, M. Virginia; Berger, David H.; Mason, Brian D.; Ten Brummelaar, Theo A.; Turner, Nils H. (2010), "The Membership and Distance of the Open Cluster Collinder 419", The Astronomical Journal, 140 (3): 744, arXiv:1006.5654, Bibcode:2010AJ....140..744R, doi:10.1088/0004-6256/140/3/744, S2CID 11647847
  8. ^ Cantat-Gaudin, T.; Jordi, C.; Vallenari, A.; Bragaglia, A.; Balaguer-Núñez, L.; Soubiran, C.; Bossini, D.; Moitinho, A.; Castro-Ginard, A.; Krone-Martins, A.; Casamiquela, L.; Sordo, R.; Carrera, R. (2018), "A Gaia DR2 view of the open cluster population in the Milky Way", Astronomy & Astrophysics, 618: A93, arXiv:1805.08726, Bibcode:2018A&A...618A..93C, doi:10.1051/0004-6361/201833476, S2CID 56245426
  9. ^ a b McKibben, W. P.; Bagnuolo, Jr, W. G.; Gies, D. R.; Hahula, M. E.; Hartkopf, W. I.; Roberts, Jr, L. C.; Bolton, C. T.; Fullerton, A. W.; Mason, B. D.; Penny, L. R.; Thaller, M. L. (1998), "A Long-Period Spectroscopic Binary in the O-Star Multiple System HD 193322", Publications of the Astronomical Society of the Pacific, 110 (750): 900–905, Bibcode:1998PASP..110..900M, doi:10.1086/316211
  10. ^ Renson, P.; Faraggiana, R.; Boehm, C. (1990), "Catalogue of Lambda Bootis Candidates", Bulletin d'Information du Centre de Donnees Stellaires, 38: 137, Bibcode:1990BICDS..38..137R