Phi1 Hydrae, Latinized from φ1 Hydrae, is a yellow-hued star in the constellation Hydra. Its apparent magnitude is 7.61,[2] making it too faint to be seen with the naked eye. Based upon an annual parallax shift of 12.3 mas as seen from Earth,[1] it is located about 266 light years from the Sun. It forms a triangle with the brighter φ2 Hydrae and φ3 Hydrae, between μ Hydrae and ν Hydrae.
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Hydra |
| Right ascension | 10h 32m 41.16026s[1] |
| Declination | −16° 57′ 31.4110″[1] |
| Apparent magnitude (V) | 7.61[2] |
| Characteristics | |
| Spectral type | G2 V[3] |
| Astrometry | |
| Radial velocity (Rv) | +15.8±0.3[4] km/s |
| Proper motion (μ) | RA: −20.964[5] mas/yr Dec.: −87.082[5] mas/yr |
| Parallax (π) | 12.2814 ± 0.0688 mas[5] |
| Distance | 266 ± 1 ly (81.4 ± 0.5 pc) |
| Absolute magnitude (MV) | +3.30[6] |
| Details[7] | |
| Mass | 1.34 M☉ |
| Radius | 2.1[5] R☉ |
| Luminosity | 4.4[6] L☉ |
| Surface gravity (log g) | 3.90±0.08 cgs |
| Temperature | 5,992±50 K |
| Metallicity [Fe/H] | +0.15±0.05 dex |
| Age | 4.1 Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
Phi1 Hydrae is an ordinary G-type main-sequence star, having a Sun-like stellar classification of G2 V and a photospheric temperature only slightly higher than the sun.[3] However, the mass is 34%[7] greater than the Sun, and it is radiating 4.4 times the Sun's luminosity.[6] Phi1 Hydrae is moving further from the Sun with a radial velocity of +15.8 km/s.[4]
References edit
- ^ a b c 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 Høg, E.; et al. (2000), "The Tycho-2 catalogue of the 2.5 million brightest stars", Astronomy and Astrophysics, 355: L27, Bibcode:2000A&A...355L..27H.
- ^ a b Houk, N.; Smith-Moore, M. (1988), "Michigan Catalogue of Two-dimensional Spectral Types for the HD Stars", Michigan Catalogue of Two-dimensional Spectral Types for the HD Stars. Volume 4, 4, Ann Arbor, MI, USA: Department of Astronomy, University of Michigan, Bibcode:1988mcts.book.....H.
- ^ 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.
- ^ 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 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 Bensby, T.; et al. (2014), "Exploring the Milky Way stellar disk. A detailed elemental abundance study of 714 F and G dwarf stars in the solar neighbourhood", Astronomy & Astrophysics, 562 (A71): 28, arXiv:1309.2631, Bibcode:2014A&A...562A..71B, doi:10.1051/0004-6361/201322631, S2CID 118786105.
- ^ "43 Hya". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-01-09.