  | |
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Hydra1 |
| Right ascension | 09h 38m 27.28962s2 |
| Declination | +04° 38′ 57.4461″2 |
| Apparent magnitude (V) | 4.683 |
| Characteristics | |
| Evolutionary stage | giant |
| Spectral type | K3 III3 |
| B−V color index | +1.310±0.0331 |
| Astrometry | |
| Radial velocity (Rv) | +44.61±0.234 km/s |
| Proper motion (μ) | RA: −163.182 mas/yr Dec.: −50.882 mas/yr |
| Parallax (π) | 11.04±0.27 mas2 |
| Distance | 295 ± 7 ly (91 ± 2 pc) |
| Absolute magnitude (MV) | −0.101 |
| Details | |
| Mass | 1.323 M☉ |
| Radius | 244 R☉ |
| Luminosity | 1913 L☉ |
| Surface gravity (log g) | 2.09±0.225 cgs |
| Temperature | 4,188±333 K |
| Metallicity [Fe/H] | −0.30±0.095 dex |
| Rotational velocity (v sin i) | 3.04 km/s |
| Age | 4.583 Gyr |
| Other designations | |
| 2 Sex, BD+05°2207, FK5 1249, HD 83425, HIP 47310, HR 3834, SAO 1178216 | |
| Database references | |
| SIMBAD | data |
2 Sextantis is a single7 star that is now in the equatorial constellation Hydra with the Bayer designation H Hydrae.8 It is located around 295 light-years away from the Sun and it is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of 4.68.3 This object is moving further from the Earth with a heliocentric radial velocity of +44.6 km/s.4 It has a relatively high proper motion, traversing the celestial sphere at the rate of 0.173″ per year.9
This is a giant star with a stellar classification of K3 III,3 which, at the age of 4.583 billion years old, has exhausted the hydrogen at its core and evolved away from the main sequence. The star has 1.32 times the mass of the Sun3 and has expanded to 24 times the Sun's radius.4 It is radiating 191 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 4,188 K.3
References
References
- 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. XHIP record for this object at VizieR.
- 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.
- Luck, R. Earle (2015), "Abundances in the Local Region. I. G and K Giants", The Astronomical Journal, 150 (3): 88, arXiv:1507.01466, Bibcode:2015AJ....150...88L, doi:10.1088/0004-6256/150/3/88, S2CID 118505114.
- 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.
- 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.
- "2 Sex". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-04-08.
- 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.
- Morton Wagman (2003). Lost Stars: Lost, Missing, and Troublesome Stars from the Catalogues of Johannes Bayer, Nicholas-Louis de Lacaille, John Flamsteed, and Sundry Others (2 ed.). McDonald & Woodward Publishing Company. ISBN 978-0-939923-78-6. OCLC 1131243914.
- Lépine, Sébastien; Shara, Michael M. (March 2005), "A Catalog of Northern Stars with Annual Proper Motions Larger than 0.15" (LSPM-NORTH Catalog)", The Astronomical Journal, 129 (3): 1483–1522, arXiv:astro-ph/0412070, Bibcode:2005AJ....129.1483L, doi:10.1086/427854, S2CID 2603568.