Epsilon Sextantis
Epsilon Sextantis, Latinized from ε Sextantis, is a solitary,[10] yellow-white hued star in the equatorial constellation of Sextans. With an apparent visual magnitude of 5.24,[2] it is faintly visible to the naked eye on a dark night. The distance to this star, based upon an annual parallax shift of 16.86 mas,[1] is about 193 light years. It is drifting further away from the Sun with a radial velocity of +15 km/s.[4]
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Sextans |
| Right ascension | 10h 17m 37.80200s[1] |
| Declination | −08° 04′ 08.0898″[1] |
| Apparent magnitude (V) | 5.24[2] |
| Characteristics | |
| Spectral type | F0 IV[3] |
| U−B color index | +0.09[2] |
| B−V color index | +0.32[2] |
| Astrometry | |
| Radial velocity (Rv) | +15.2[4] km/s |
| Proper motion (μ) | RA: −160.57[1] mas/yr Dec.: +2.91[1] mas/yr |
| Parallax (π) | 16.86 ± 0.28 mas[1] |
| Distance | 193 ± 3 ly (59.3 ± 1.0 pc) |
| Absolute magnitude (MV) | 2.42[5] |
| Details | |
| Mass | 1.94[6] M☉ |
| Radius | 3.14+0.18 −0.30[7] R☉ |
| Luminosity | 23.24±0.55[7] L☉ |
| Surface gravity (log g) | 3.83±0.08[8] cgs |
| Temperature | 7,166±88[8] K |
| Metallicity [Fe/H] | +0.31±0.05[8] dex |
| Rotational velocity (v sin i) | 63.5±3.2[5] km/s |
| Age | 1.1[6] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is an F-type subgiant star with a stellar classification of F0 IV.[3] However, Malaroda (1975) gave a classification of F2 III,[11] which would indicate a more evolved giant star. It is estimated to have nearly double the mass of the Sun[6] with 3.1[7] times the Sun's radius. The star is around 1.1 billion years old and has a projected rotational velocity of 63.5 km/s.[5] It is radiating 23[7] times the luminosity of the Sun from its photosphere at an effective temperature of 7,166 K.[8]
References edit
- ^ 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.
- ^ a b c d Mermilliod, J.-C. (1986), "Compilation of Eggen's UBV data, transformed to UBV (unpublished)", SIMBAD, Bibcode:1986EgUBV........0M.
- ^ a b Houk, N.; Swift, C. (1999), "Michigan catalogue of two-dimensional spectral types for the HD Stars", Michigan Spectral Survey, 5, Ann Arbor, Michigan: Department of Astronomy, University of Michigan, Bibcode:1999MSS...C05....0H.
- ^ a b Wilson, Ralph Elmer (1953), "General Catalogue of Stellar Radial Velocities", Carnegie Institute Washington D.C. Publication, Washington: Carnegie Institution of Washington, Bibcode:1953GCRV..C......0W.
- ^ a b c Reiners, Ansgar (January 2006), "Rotation- and temperature-dependence of stellar latitudinal differential rotation", Astronomy and Astrophysics, 446 (1): 267–277, arXiv:astro-ph/0509399, Bibcode:2006A&A...446..267R, doi:10.1051/0004-6361:20053911, S2CID 8642707
- ^ a b c David, Trevor J.; Hillenbrand, Lynne A. (2015), "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets", The Astrophysical Journal, 804 (2): 146, arXiv:1501.03154, Bibcode:2015ApJ...804..146D, doi:10.1088/0004-637X/804/2/146, S2CID 33401607.
- ^ 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.
- ^ a b c d Prugniel, Ph.; et al. (July 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.
- ^ "* eps Sex". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2016-12-16.
{{cite web}}: CS1 maint: postscript (link) - ^ Eggleton, P. P.; et al. (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.
- ^ Malaroda, S. (August 1975), "Study of the F-type stars. I. MK spectral types", Astronomical Journal, 80: 637–641, Bibcode:1975AJ.....80..637M, doi:10.1086/111786.