Phi2 Ceti
Phi2 Ceti, Latinized from φ2 Ceti), is a star located in the equatorial constellation of Cetus. φ2 Ceti is also known as 19 Cet, and HD 4813. Based upon parallax measurements, it is located about 51 light years away. It has an apparent visual magnitude of +5.19, making it bright enough to be seen with the naked eye. The star is drifting further away with a radial velocity of +8 km/s.[1]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Cetus |
| Right ascension | 00h 50m 07.58859s[1] |
| Declination | −10° 38′ 39.5848″[1] |
| Apparent magnitude (V) | 5.172[2] |
| Characteristics | |
| Spectral type | F7V[3] |
| U−B color index | +0.009[2] |
| B−V color index | +0.518[2] |
| Astrometry | |
| Radial velocity (Rv) | +8.23±0.17[1] km/s |
| Proper motion (μ) | RA: –226.91[4] mas/yr Dec.: –229.75[4] mas/yr |
| Parallax (π) | 62.9723 ± 0.1614 mas[1] |
| Distance | 51.8 ± 0.1 ly (15.88 ± 0.04 pc) |
| Absolute magnitude (MV) | 4.23[5] |
| Details | |
| Mass | 1.19[6] M☉ |
| Radius | 1.17+0.03 −0.01[1] R☉ |
| Luminosity | 1.852+0.006 −0.007[1] L☉ |
| Surface gravity (log g) | 4.45[6] cgs |
| Temperature | 6,352[6] K |
| Metallicity [Fe/H] | −0.03[6] dex |
| Rotational velocity (v sin i) | 4.3[7] km/s |
| Age | 1.9[6] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is an ordinary F-type main sequence star with a stellar classification of F7V. The star is estimated to be 1.9[6] billion years old and is spinning with a projected rotational velocity of 4.3 km/s.[7] It has 1.2[6] times the mass and 1.17[1] times the radius of the Sun. The star is radiating 1.85[1] times the luminosity of the Sun from its photosphere at an effective temperature of 6,352 K.[6] It is a suspected variable star of unknown type, with a brightness that has been measured ranging from magnitude 5.15 down to 5.24.[8]
References
- ^ a b c d e f g h i 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 Gutierrez-Moreno, Adelina; et al. (1966), A System of photometric standards, vol. 1, Publicaciones Universidad de Chile, Department de Astronomy, pp. 1–17, Bibcode:1966PDAUC...1....1G.
- ^ Gray, R. O.; et al. (2006), "Contributions to the Nearby Stars (NStars) Project: spectroscopy of stars earlier than M0 within 40 pc-The Southern Sample", The Astronomical Journal, 132 (1): 161–70, arXiv:astro-ph/0603770, Bibcode:2006AJ....132..161G, doi:10.1086/504637, S2CID 119476992.
- ^ a b van Leeuwen, F. (November 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.
- ^ Paunzen, E.; et al. (July 2014), "Investigating the possible connection between λ Bootis stars and intermediate Population II type stars", Astronomy & Astrophysics, 567: 8, arXiv:1406.3936, Bibcode:2014A&A...567A..67P, doi:10.1051/0004-6361/201423817, S2CID 56332289, A67.
- ^ a b c d e f g h 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.
- ^ a b Schröder, C.; Reiners, Ansgar; Schmitt, Jürgen H. M. M. (January 2009), "Ca II HK emission in rapidly rotating stars. Evidence for an onset of the solar-type dynamo" (PDF), Astronomy and Astrophysics, 493 (3): 1099–1107, Bibcode:2009A&A...493.1099S, doi:10.1051/0004-6361:200810377
- ^ Samus, N. N.; et al. (2017), "General Catalogue of Variable Stars", Astronomy Reports, 5.1, 61 (1): 80–88, Bibcode:2017ARep...61...80S, doi:10.1134/S1063772917010085, S2CID 125853869.