Tau1 Serpentis
Tau1 Serpentis, Latinized from τ1 Serpentis, is a single[10] star in the Caput (Head) segment of the equatorial constellation of Serpens. It is a red hued star that is dimly visible to the naked eye with an apparent visual magnitude of 5.16.[3] Based upon parallax measurements, this star is located at a distance of approximately 990 light years from the Sun,[2] while it is drifting closer with a radial velocity of −16.5 km/s.[3]
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Serpens |
| Right ascension | 15h 25m 47.39664s[2] |
| Declination | +15° 25′ 40.9307″[2] |
| Apparent magnitude (V) | 5.16[3] (5.13 to 5.20)[4] |
| Characteristics | |
| Evolutionary stage | AGB[5] |
| Spectral type | M1III[6] |
| U−B color index | +1.95[7] |
| B−V color index | +1.650±0.006[3] |
| R−I color index | +1.04[7] |
| Astrometry | |
| Radial velocity (Rv) | −16.51±0.23[3] km/s |
| Proper motion (μ) | RA: −12.467[2] mas/yr Dec.: −7.740[2] mas/yr |
| Parallax (π) | 3.3030 ± 0.1988 mas[2] |
| Distance | 990 ± 60 ly (300 ± 20 pc) |
| Absolute magnitude (MV) | −1.45[3] |
| Details | |
| Radius | 99+7 −14[2] R☉ |
| Luminosity | 2,158±149[2] L☉ |
| Surface gravity (log g) | 1.07±0.18[8] cgs |
| Temperature | 3,954+309 −132[2] K |
| Metallicity [Fe/H] | 0.05±0.06[8] dex |
| Other designations | |
| Database references | |
| SIMBAD | data |
This object is an aging red giant star, currently on the asymptotic giant branch,[5] with a stellar classification of M1III.[6] Having exhausted the supply of hydrogen at its core, it has cooled and expanded until it now has around 99[2] times the girth of the Sun.[2] It is a suspected variable star with a brightness that has been measured varying from magnitude 5.13 down to 5.20.[4] The Hipparcos data for Tau1 Serpentis shows brightness variations with a period of 6.4675 days, and an amplitude of 0.0066 magnitudes.[11] The star is radiating 2,158[2] times the luminosity of the Sun from its swollen photosphere at an effective temperature of 3,954 K.[2]
References
- ^ "/ftp/cats/more/HIP/cdroms/cats". Centre de Données astronomiques de Strasbourg. Strasbourg astronomical Data Center. Retrieved 15 October 2022.
- ^ a b c d e f g h i j k l m 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.
- ^ a b c d e f 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.
- ^ a b Samus', N. N; Kazarovets, E. V; Durlevich, O. V; Kireeva, N. N; Pastukhova, E. N (2017), "General catalogue of variable stars: Version GCVS 5.1", Astronomy Reports, 61 (1): 80, Bibcode:2017ARep...61...80S, doi:10.1134/S1063772917010085, S2CID 125853869.
- ^ a b Eggen, Olin J. (July 1992), "Asymptotic giant branch stars near the sun", Astronomical Journal, 104 (1): 275–313, Bibcode:1992AJ....104..275E, doi:10.1086/116239.
- ^ a b Cenarro, A. J.; et al. (July 2009), "Mg and TiO spectral features at the near-IR: spectrophotometric index definitions and empirical calibrations", Monthly Notices of the Royal Astronomical Society, 396 (4): 1895–1914, arXiv:0903.4835, Bibcode:2009MNRAS.396.1895C, doi:10.1111/j.1365-2966.2009.14839.x, S2CID 15729759.
- ^ a b Hoffleit, D.; Warren, Jr., W. H., "HR 5739", The Bright Star Catalogue (5th Revised ed.), retrieved 2019-10-17.
- ^ a b Prugniel, P.; et al. (2011), "The atmospheric parameters and spectral interpolator for the MILES stars", Astronomy & Astrophysics, 531: A165, arXiv:1104.4952, Bibcode:2011A&A...531A.165P, doi:10.1051/0004-6361/201116769, S2CID 54940439.
- ^ "tau01 Ser". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-10-17.
- ^ 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.
- ^ Koen, Chris; Eyer, Laurent (March 2002). "New periodic variables from the Hipparcos epoch photometry". Monthly Notices of the Royal Astronomical Society. 331 (1): 45–59. arXiv:astro-ph/0112194. Bibcode:2002MNRAS.331...45K. doi:10.1046/j.1365-8711.2002.05150.x. S2CID 10505995.