HR 7484

HR 7484

A light curve for V1143 Cygni, plotted from TESS data
Observation data
Epoch J2000      Equinox ICRS
Constellation Cygnus
Right ascension 19h 38m 41.18316s
Declination +54° 58′ 25.6420″
Apparent magnitude (V) 5.889±0.015, 6.37
Characteristics
Spectral type F6V (F5 V + F5 V)
B−V color index 0.482±0.004
Variable type Algol
Astrometry
Radial velocity (Rv)−13.9±0.2 km/s
Proper motion (μ) RA: +34.885 mas/yr
Dec.: +162.839 mas/yr
Parallax (π)24.7090±0.0422 mas
Distance133.79 ± 0.72 ly
(41.02±0.22 pc)
Absolute magnitude (MV)2.83
Orbit
Period (P)7.640735±0.000004 d
Semi-major axis (a)(2.57±0.03)×10−3"
(22.71±0.03 R☉)
Eccentricity (e)0.5386±0.0004
Inclination (i)86.73±0.76°
Longitude of the node (Ω)50.9±0.6°
Periastron epoch (T)2454598.1930±0.0008 HJD
Argument of periastron (ω)
(secondary)		49.11±0.10°
Semi-amplitude (K1)
(primary)		88.15±0.06 km/s
Semi-amplitude (K2)
(secondary)		90.08±0.08 km/s
Details
A
Mass1.361±0.004 M☉
Radius1.348±0.016 R☉
Luminosity3.35±0.44 L☉
Surface gravity (log g)4.31±0.03 cgs
Temperature6,620±190 K
Metallicity [Fe/H]+0.08 dex
Rotational velocity (v sin i)19.1±0.6 km/s
Age500 Myr
B
Mass1.332±0.004 M☉
Radius1.322±0.016 R☉
Luminosity3.13±0.50 L☉
Surface gravity (log g)4.32±0.04 cgs
Temperature6,570±220 K
Rotational velocity (v sin i)27.9±1.2 km/s
Age500 Myr
Other designations
V1143 Cyg, HD 185912, HIP 96620, HR 7484, SAO 31850
Database references
SIMBADdata

HR 7484 (V1143 Cyg) is a binary star system in the northern constellation of Cygnus. It is dimly visible to the naked eye under good viewing conditions, having an apparent visual magnitude of 5.89. Based upon dynamical parallax measurements, it is located 41.02 ± 0.22 parsecs (133.79 ± 0.72 light-years) away. The system is moving closer with a heliocentric radial velocity of −14 km/s.

Observational history

Radial velocity measurements taken at the Dominion Astrophysical Observatory in Victoria, British Columbia Canada in 1919 led to the determination by William Edmund Harper that HR 7484 is a double-lined spectroscopic binary. The next year he published an orbit with a period of 7.6383 days as compared to the modern value of 7.640735 days.

Physical characteristics

HR 7484 is a detached eclipsing binary, which means the orbital plane is aligned close to the line-of-sight from the Earth, causing the components to eclipse twice per orbit. The system is undergoing apsidal motion, with a rate greater than that predicted by general relativity. Both components are ordinary F-type main-sequence stars with similar physical properties. The star normally has an apparent magnitude of 5.89, but every 7.64 days (7 days, 15 hours, and 22 minutes) its brightness decreases to magnitude 6.37, approximately two thirds as bright. Five days and 17 hours after each primary eclipse, there is a secondary eclipse when the brightness drops to magnitude 6.06, about 85% of the normal brightness. Each eclipse lasts for 220 minutes. Both eclipses are partial.

References

  1. ↑ "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. Retrieved 8 December 2021.
  2. ↑ Roman, Nancy G. (1987). "Identification of a constellation from a position". Publications of the Astronomical Society of the Pacific. 99 (617): 695. Bibcode:1987PASP...99..695R. doi:10.1086/132034. Constellation record for this object at VizieR.
  3. 1 2 3 4 5 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.
  4. 1 2 3 4 5 Graczyk, Dariusz; et al. (March 2017). "The Surface Brightness-color Relations Based on Eclipsing Binary Stars: Toward Precision Better than 1% in Angular Diameter Predictions". The Astrophysical Journal. 837 (1): 19. arXiv:1611.09976. Bibcode:2017ApJ...837....7G. doi:10.3847/1538-4357/aa5d56. S2CID 119004886. 7.
  5. 1 2 3 Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 1. Bibcode:2009yCat....102025S.
  6. 1 2 3 4 5 Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.
  7. 1 2 3 4 5 Lester, Kathryn V.; Gies, Douglas R.; Schaefer, Gail H.; Farrington, Christopher D.; Guo, Zhao; Matson, Rachel A.; Monnier, John D.; ten Brummelaar, Theo; Sturmann, Judit; Vargas, Norman; Weiss, Samuel A. (December 2019). "Visual Orbits of Spectroscopic Binaries with the CHARA Array. II. The Eclipsing Binary HD 185912". The Astronomical Journal. 158 (6): 218. arXiv:1909.09161. Bibcode:2019AJ....158..218L. doi:10.3847/1538-3881/ab449d. ISSN 0004-6256.
  8. ↑ "HD 185912". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-07-14.
  9. ↑ Plaskett, J. S.; et al. (1919). "Fourth list of spectroscopic binaries". Journal of the Royal Astronomical Society of Canada. 13: 372–378. Bibcode:1919JRASC..13..372P.
  10. ↑ Harper, W. E. (1920). "The orbits of the spectroscopic components of Boss 5026". Astrophysical Journal. 51: 187–189. Bibcode:1920ApJ....51..187H. doi:10.1086/142537.
  11. 1 2 Dariush, A.; et al. (April 2005). "Photometric Observations and Apsidal Motion Study of V1143 Cyg". Astrophysics and Space Science. 296 (1–4): 141–144. arXiv:astro-ph/0411788. Bibcode:2005Ap&SS.296..141D. doi:10.1007/s10509-005-4416-0. S2CID 119369053.
  12. ↑ Anderson, J.; Garcia, J.; Gimenez, A.; Nordstrom, B. (1987). "Absolute dimensions of eclipsing binaries. X - V1143 Cygni". Astronomy & Astrophysics. 174: 107–115. Bibcode:1987A&A...174..107A.