6 Serpentis

6 Serpentis
Observation data
Epoch J2000      Equinox J2000
Constellation Serpens
Right ascension 15h 21m 01.99609s[1]
Declination +00° 42′ 55.2213″[1]
Apparent magnitude (V) 5.382[2] (5.54 + 9.42)[3]
Characteristics
Spectral type K3 III[2]
B−V color index 1.224[2]
Astrometry
Radial velocity (Rv)+9.7±0.3[4] km/s
Proper motion (μ) RA: −42.36[1] mas/yr
Dec.: −103.14[1] mas/yr
Parallax (π)13.63 ± 0.73 mas[1]
Distance240 ± 10 ly
(73 ± 4 pc)
Absolute magnitude (MV)1.03[5]
Details[2]
6 Ser A
Mass1.27 M☉
Radius12[6] R☉
Luminosity55 L☉
Surface gravity (log g)2.4[6] cgs
Temperature4,417±17 K
Metallicity [Fe/H]−0.02[7] dex
Rotational velocity (v sin i)2.4[6] km/s
Age6.03 Gyr
Other designations
6 Ser, BD+01° 3067, HD 136514, HIP 75119, HR 5710, SAO 120955, ADS 9596, WDS J15210+0043[8]
Database references
SIMBADdata

6 Serpentis is a binary star[3] system in the constellation Serpens. It has a combined apparent visual magnitude of 5.382,[2] which is bright enough to be faintly visible to the naked eye. The distance to this system, based upon an annual parallax shift of 13.63±0.73 mas,[1] is about 240 light years. It is moving further from the Sun with a heliocentric radial velocity of +10 km/s.[4]

The primary, component A, is an evolved red giant of spectral type K3III,[2] a star that has used up its core hydrogen and has expanded. At the age of around six billion years it is a red clump star,[7][9] indicating it is on the horizontal branch and is generating energy through helium fusion at its core. The star has 1.27[2] times the mass of the Sun and has expanded to 12[6] times the Sun's radius. It is radiating 55[2] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,417 K.[2]

As of 2005, the magnitude 9.42[3] secondary, component B, was at an angular separation of 3.329″±0.017″ along a position angle of 21.8°±0.3°.[10]

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.
  2. ^ a b c d e f g h i Luck, R. Earle (September 2015), "Abundances in the Local Region. I. G and K Giants", The Astronomical Journal, 150 (3): 23, arXiv:1507.01466, Bibcode:2015AJ....150...88L, doi:10.1088/0004-6256/150/3/88, S2CID 118505114, 88.
  3. ^ a b c Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
  4. ^ a b de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics, 546: 14, arXiv:1208.3048, Bibcode:2012A&A...546A..61D, doi:10.1051/0004-6361/201219219, S2CID 59451347, A61.
  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.
  6. ^ a b c d Massarotti, Alessandro; et al. (January 2008), "Rotational and Radial Velocities for a Sample of 761 Hipparcos Giants and the Role of Binarity", The Astronomical Journal, 135 (1): 209–231, Bibcode:2008AJ....135..209M, doi:10.1088/0004-6256/135/1/209, S2CID 121883397.
  7. ^ a b Laney, C. D.; et al. (2012), "A new Large Magellanic Cloud K-band distance from precision measurements of nearby red clump stars", Monthly Notices of the Royal Astronomical Society, 419 (2): 1637, arXiv:1109.4800, Bibcode:2012MNRAS.419.1637L, doi:10.1111/j.1365-2966.2011.19826.x, S2CID 117788450.
  8. ^ "6 Ser". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-03-19.
  9. ^ Alves, David R. (August 2000), "K-Band Calibration of the Red Clump Luminosity", The Astrophysical Journal, 539 (2): 732–741, arXiv:astro-ph/0003329, Bibcode:2000ApJ...539..732A, doi:10.1086/309278, S2CID 16673121.
  10. ^ Scardia, M.; et al. (January 2007), "Speckle observations with PISCO in Merate - III. Astrometric measurements of visual binaries in 2005 and scale calibration with a grating mask" (PDF), Monthly Notices of the Royal Astronomical Society, 374 (3): 965–978, Bibcode:2007MNRAS.374..965S, doi:10.1111/j.1365-2966.2006.11206.x.