Tau2 Serpentis

For other stars with this Bayer designation, see Tau Serpentis.
τ2 Serpentis
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Serpens
Right ascension 15h 32m 09.67495s[1]
Declination +16° 03′ 22.2056″[1]
Apparent magnitude (V) 6.22[2]
Characteristics
Spectral type B9V[3]
U−B color index −0.23[4]
B−V color index −0.038±0.005[2]
Astrometry
Radial velocity (Rv)−19.3±2.7[2] km/s
Proper motion (μ) RA: −2.92[5] mas/yr
Dec.: +6.48[5] mas/yr
Parallax (π)6.7936 ± 0.0928 mas[1]
Distance480 ± 7 ly
(147 ± 2 pc)
Absolute magnitude (MV)+0.44[2]
Details
Mass2.89±0.08[6] M☉
Radius2.7[7] R☉
Luminosity96.4+15.3
−12.6[6] L☉
Temperature10,839+60
−50[6] K
Rotational velocity (v sin i)154[6] km/s
Age278[8] Myr
Other designations
τ2 Ser, 12 Serpentis, BD+16°2797, GC 20880, HD 138527, HIP 76069, HR 5770, SAO 101600, PPM 131484[9]
Database references
SIMBADdata

Tau2 Serpentis, Latinized from τ2 Serpentis, is a star in the constellation of Serpens, located approximately 480 light-years from the Sun.[1] It is a challenge to view with the naked eye, having an apparent visual magnitude of 6.22.[2] The star is drifting closer with a radial velocity of −19 km/s.[2]

This object is a late B-type main-sequence star with a stellar classification of B9V.[3] It is a probable Lambda Boötis star.[2][10] The star is 278[8] million years old and is spinning with a projected rotational velocity of 154 km/s.[6] It has nearly three times the mass and radius of the Sun.[6][7] Tau2 Serpentis is radiating 96[6] times the Sun's luminosity from its photosphere at an effective temperature of 10,839 K.[6]

There is evidence of a possible companion, which is contributing about 15% to the total emission of the system.[11]

References

  1. ^ a b c d 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.
  2. ^ a b c d e f g 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.
  3. ^ a b Cowley, A.; et al. (April 1969), "A study of the bright A stars. I. A catalogue of spectral classifications", Astronomical Journal, 74: 375–406, Bibcode:1969AJ.....74..375C, doi:10.1086/110819.
  4. ^ Hoffleit, D.; Warren, Jr., W. H., The Bright Star Catalogue (5th Revised ed.), CDS. HR 5770. Accessed on line September 19, 2008.
  5. ^ a b 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.
  6. ^ a b c d e f g h Zorec, J.; Royer, F. (2012), "Rotational velocities of A-type stars. IV. Evolution of rotational velocities", Astronomy & Astrophysics, 537: A120, arXiv:1201.2052, Bibcode:2012A&A...537A.120Z, doi:10.1051/0004-6361/201117691, S2CID 55586789.
  7. ^ a b Pasinetti Fracassini, L. E.; et al. (2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)", Astronomy & Astrophysics, 367 (2) (Third ed.): 521–24, arXiv:astro-ph/0012289, Bibcode:2001A&A...367..521P, doi:10.1051/0004-6361:20000451, S2CID 425754. HD 138527 Accessed on line September 19, 2008.
  8. ^ a b Gontcharov, G. A. (November 2012), "Spatial distribution and kinematics of OB stars", Astronomy Letters, 38 (11): 694–706, arXiv:1606.09028, Bibcode:2012AstL...38..694G, doi:10.1134/S1063773712110035, S2CID 119108982.
  9. ^ "tau02 Ser". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-10-18.
  10. ^ Murphy, Simon J.; et al. (October 2015), "An Evaluation of the Membership Probability of 212 λ Boo Stars. I. A Catalogue", Publications of the Astronomical Society of Australia, 32: 43, arXiv:1508.03633, Bibcode:2015PASA...32...36M, doi:10.1017/pasa.2015.34, S2CID 59405545, e036
  11. ^ Zverko, J.; et al. (January 2013), "Stars with discrepant v sin i as derived from Ca II λ 3933 Å and Mg II λ 4481 Å lines. III. Stars with v sin i ( λ 3933 Å) < v sin i ( λ 4481 Å)", Astrophysical Bulletin, 68 (1): 57–77, Bibcode:2013AstBu..68...57Z, doi:10.1134/S1990341313010069, S2CID 121236297.