HD 199223 (HR 8010) is a double star in the equatorial constellation Delphinus. However, the system was originally in Equuleus prior to the creation of official IAU constellation borders.[15] The components have a separation of 2 at a position angle of 282° as of 2016.[16] They have apparent magnitudes of 6.34 and 7.49 and distances of 354 and 359 light years respectively. The system is drifting closer with a radial velocity of −33 km/s.

HD 199223
Location of HD 199223 (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Delphinus
A
Right ascension 20h 55m 40.6778s[1]
Declination +04° 31′ 57.7994″[1]
Apparent magnitude (V) 6.34±0.01[2]
B
Right ascension 20h 55m 40.5439s[3]
Declination +04° 31′ 58.2271″[3]
Apparent magnitude (V) 7.49±0.01[2]
Characteristics
A
Spectral type G8 III/IV[4]
U−B color index +0.49[5]
B−V color index +0.82[5]
B
Spectral type F/G[6]
Astrometry
Radial velocity (Rv)−32.6±0.4[7] km/s
Absolute magnitude (MV)+0.33[8]
A
Proper motion (μ) RA: +60.413[1] mas/yr
Dec.: +10.949[1] mas/yr
Parallax (π)9.2067 ± 0.0354 mas[1]
Distance354 ± 1 ly
(108.6 ± 0.4 pc)
B
Proper motion (μ) RA: +60.315[3] mas/yr
Dec.: +9.758[3] mas/yr
Parallax (π)9.0757 ± 0.0758 mas[3]
Distance359 ± 3 ly
(110.2 ± 0.9 pc)
Details
A
Mass1.25[9] M
Radius8.26+0.65
−0.22
[10] R
Luminosity37.1±0.4[10] L
Surface gravity (log g)2.60±0.25[11] cgs
Temperature4,956+68
−185
[10] K
Metallicity [Fe/H]0.13±0.09[11] dex
Rotational velocity (v sin i)<1[12] km/s
B
Mass1.46[9] M
Radius2.10+0.16
−0.27
[13] R
Luminosity8.82±0.23[13] L
Surface gravity (log g)3.85[9] cgs
Temperature6,865+494
−251
[13] K
Metallicity [Fe/H]−0.2[9] dex
Other designations
1 G. Equulei, AG+04°2834, BD+03°4461, GC 29200, HD 199223, HIP 103301, HR 8010, SAO 126373, WDS J20557+0432[14]
Database references
SIMBADThe system
A
B

The brighter component has a stellar classification of G8 III/IV,[4] indicating that it is a G-type star with the blended luminosity class of a giant star and a subgiant. It has 125% of the mass of the Sun[9] and an enlarged radius of 8.26 R.[10] It shines at 37.1 times the luminosity of the Sun[10] from its photosphere at an effective temperature of 4,956 K,[10] giving it a yellow glow. HD 199223A's iron abundance is 135% that of the Sun[11] and it spins modestly with a projected rotational velocity less than km/s.[12]

As for the dimmer one, it is classified as an F/G star,[6] and is calculated to be an F-type subgiant. It has 146% of the mass of the Sun[9] and 2.1 times its radius.[13] It radiates with a luminosity of 8.82 L[13] from its photosphere at an effective temperature of 6,865 K,[13] giving it a yellow white glow.

References

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  1. ^ a b c d e 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.
  2. ^ a b Fabricius, C.; Høg, E.; Makarov, V. V.; Mason, B. D.; Wycoff, G. L.; Urban, S. E. (March 2002). "The Tycho double star catalogue". Astronomy & Astrophysics. 384 (1): 180–189. Bibcode:2002A&A...384..180F. doi:10.1051/0004-6361:20011822. ISSN 0004-6361.
  3. ^ a b c d e 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.
  4. ^ a b Harlan, E. A. (June 1974). "MK classifications for F-and G-type stars. 3". The Astronomical Journal. 79: 682. Bibcode:1974AJ.....79..682H. doi:10.1086/111597. ISSN 0004-6256.
  5. ^ a b Johnson, H. L.; Mitchell, R. I.; Iriarte, B.; Wisniewski, W. Z. (1966). "UBVRIJKL Photometry of the Bright Stars". Communications of the Lunar and Planetary Laboratory. 4: 99–110. Bibcode:1966CoLPL...4...99J.
  6. ^ a b Houk, N.; Swift, C. (1999). "Michigan catalogue of two-dimensional spectral types for the HD Stars, Vol. 5". Michigan Spectral Survey. 5: 0. Bibcode:1999MSS...C05....0H.
  7. ^ Gontcharov, G. A. (November 2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. ISSN 1063-7737. S2CID 119231169.
  8. ^ Anderson, E.; Francis, Ch. (May 2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331–346. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. ISSN 1063-7737. S2CID 255204555.
  9. ^ a b c d e f Anders, F.; et al. (August 2019). "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18". Astronomy & Astrophysics. 628: A94. arXiv:1904.11302. Bibcode:2019A&A...628A..94A. doi:10.1051/0004-6361/201935765. ISSN 0004-6361.
  10. ^ a b c d e f Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
  11. ^ a b c Randich, S.; Gratton, R.; Pallavicini, R.; Pasquini, L.; Carretta, E. (August 1999). "Lithium in population I subgiants". Astronomy and Astrophysics. 348: 487–500. Bibcode:1999A&A...348..487R. ISSN 0004-6361.
  12. ^ a b de Medeiros, J. R.; Mayor, M. (November 1999). "A catalog of rotational and radial velocities for evolved stars". Astronomy and Astrophysics Supplement Series. 139 (3): 433–460. Bibcode:1999A&AS..139..433D. doi:10.1051/aas:1999401. ISSN 0365-0138.
  13. ^ a b c d e f Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
  14. ^ Gould, Benjamin Apthorp (1878). "Uranometria Argentina : brillantez y posicion de las estrellas fijas, hasta la septima magnitud, comprendidas dentro de cien grados del polo austral : con atlas". Resultados del Observatorio Nacional Argentino. 1. Bibcode:1879RNAO....1.....G.
  15. ^ Davenhall, A. C.; Leggett, S. K. (May 1997). "VizieR Online Data Catalog: Constellation Boundary Data (Davenhall+ 1989)". VizieR Online Data Catalog: VI/49. Bibcode:1997yCat.6049....0D.
  16. ^ Mason, Brian D.; Wycoff, Gary L.; Hartkopf, William I.; Douglass, Geoffrey G.; Worley, Charles E. (December 2001). "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog". The Astronomical Journal. 122 (6): 3466–3471. Bibcode:2001AJ....122.3466M. doi:10.1086/323920. ISSN 0004-6256.