ρ Cygni
Location of ρ Cygni (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Cygnus
Right ascension 21h 33m 58.85298s[1]
Declination 45° 35′ 30.6179″[1]
Apparent magnitude (V) 4.02 [2]
Characteristics
Spectral type G8 III Fe-0.5[3]
U−B color index +0.56[2]
B−V color index +0.89[2]
Astrometry
Radial velocity (Rv)+6.88[4] km/s
Proper motion (μ) RA: −23.79[1] mas/yr
Dec.: −93.70[1] mas/yr
Parallax (π)26.39 ± 0.15 mas[1]
Distance123.6 ± 0.7 ly
(37.9 ± 0.2 pc)
Absolute magnitude (MV)1.11[5]
Details
Mass2.16[6] M☉
Radius7.81[6] R☉
Luminosity37.1[6] L☉
Temperature5,100[6] K
Metallicity [Fe/H]−0.05[7] dex
Rotational velocity (v sin i)0.71[7] km/s
Age660[7] Myr
Other designations
ρ Cyg, 73 Cygni, BD+44° 3865, FK5 1568, GC 30207, HD 205435, HIP 106481, HR 8252, SAO 51035
Database references
SIMBADdata

Rho Cygni, Latinized from ρ Cygni, is a yellow-hued star in the northern constellation of Cygnus. It is visible to the naked eye with an apparent magnitude of 4.02.[2] The measured annual parallax shift is 26.39 milliarcseconds,[1] which yields a distance estimate of 124 light years. It is moving further from the Sun with a radial velocity of +6.88.[4] The star is a member of the thin disk population of the Milky Way galaxy.[7]

This is an evolved giant star of type G with an estimated age of 660[7] million years and a stellar classification of G8 III Fe-0.5.[3] The suffix notation indicates the spectrum shows a mild underabundance of iron in the outer atmosphere. It has about 2.16 times the mass of the Sun and 7.81 times the Sun's girth.[6] The star is radiating 37 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 5,100 K.[6]

Rho Cygni is a bright X-ray source with a luminosity of 10.26×1029 ergs s−1.[8] It has a maximum magnetic field strength of 7.3±0.5 G[9] at the surface.

References

  1. ^ a b c d e f van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. S2CID 18759600. Vizier catalog entry
  2. ^ a b c d Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues. 2237: 0. Bibcode:2002yCat.2237....0D.
  3. ^ a b Keenan, Philip C.; McNeil, Raymond C. (1989). "The Perkins catalog of revised MK types for the cooler stars". Astrophysical Journal Supplement Series. 71: 245. Bibcode:1989ApJS...71..245K. doi:10.1086/191373.
  4. ^ a b Soubiran, C.; et al. (March 2008), "Vertical distribution of Galactic disk stars. IV. AMR and AVR from clump giants", Astronomy and Astrophysics, 480 (1): 91–101, arXiv:0712.1370, Bibcode:2008A&A...480...91S, doi:10.1051/0004-6361:20078788, S2CID 16602121
  5. ^ Da Silva, Ronaldo; et al. (August 2015). "Homogeneous abundance analysis of FGK dwarf, subgiant, and giant stars with and without giant planets". Astronomy and Astrophysics. 580A: 24–42. arXiv:1505.01726. Bibcode:2015A&A...580A..24D. doi:10.1051/0004-6361/201525770. S2CID 119216425. Vizier catalog entry
  6. ^ a b c d e f Reffert, Sabine; et al. (2015). "Precise radial velocities of giant stars. VII. Occurrence rate of giant extrasolar planets as a function of mass and metallicity". Astronomy and Astrophysics. 574A (2): 116–129. arXiv:1412.4634. Bibcode:2015A&A...574A.116R. doi:10.1051/0004-6361/201322360. hdl:10722/215277. S2CID 59334290. Vizier catalog entry
  7. ^ a b c d e Jofré, E.; et al. (2015). "Stellar parameters and chemical abundances of 223 evolved stars with and without planets". Astronomy & Astrophysics. 574: A50. arXiv:1410.6422. Bibcode:2015A&A...574A..50J. doi:10.1051/0004-6361/201424474. S2CID 53666931.
  8. ^ Makarov, Valeri V. (October 2003), "The 100 Brightest X-Ray Stars within 50 Parsecs of the Sun", The Astronomical Journal, 126 (4): 1996–2008, Bibcode:2003AJ....126.1996M, doi:10.1086/378164.
  9. ^ Aurière, M.; et al. (February 2015), "The magnetic fields at the surface of active single G-K giants", Astronomy & Astrophysics, 574: 30, arXiv:1411.6230, Bibcode:2015A&A...574A..90A, doi:10.1051/0004-6361/201424579, S2CID 118504829, A90.
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