Zeta2 Antliae is the Bayer designation for a star in the southern constellation of Antlia, the air pump. With an apparent visual magnitude of 5.91,[2] it is a relatively faint star that requires dark suburban skies for viewing with the naked eye. Parallax measurements show it to be located at a distance of roughly 386 light-years (118 parsecs) from Earth.[1]
  | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Antlia |
| Right ascension | 09h 31m 32.15879s[1] |
| Declination | −31° 52′ 18.5989″[1] |
| Apparent magnitude (V) | 5.91[2] |
| Characteristics | |
| Spectral type | A9 IV[3] |
| U−B color index | +0.16[2] |
| B−V color index | +0.23[2] |
| Astrometry | |
| Radial velocity (Rv) | +19.8 ± 1.6[4] km/s |
| Proper motion (μ) | RA: -47.968 ± 0.162[5] mas/yr Dec.: -8.784 ± 0.179[5] mas/yr |
| Parallax (π) | 8.4565 ± 0.1075 mas[5] |
| Distance | 386 ± 5 ly (118 ± 2 pc) |
| Absolute magnitude (MV) | +0.44[6] |
| Details | |
| Mass | 1.71[7] M☉ |
| Radius | 4.22[7] R☉ |
| Luminosity | 49.5[7] L☉ |
| Surface gravity (log g) | 3.42[7] cgs |
| Temperature | 7,455[7] K |
| Other designations | |
| Database references | |
| SIMBAD | data |
The spectrum of this star matches a stellar classification of A9 IV,[3] where the luminosity class of IV indicate that this is a subgiant star that is evolving away from the main sequence as the supply of hydrogen at its core is becoming exhausted. This is catalogued as an Am star, which means it is a chemically peculiar star that shows strong indications of certain trace metals in its spectrum.[6] The chemical peculiarity is now considered doubtful.[9]
References
edit- ^ a b c 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.
- ^ a b c d Mendoza, E. E.; Gomez, V. T.; Gonzalez, S. (June 1978), "UBVRI photometry of 225 Am stars", The Astronomical Journal, 83: 606–614, Bibcode:1978AJ.....83..606M, doi:10.1086/112242.
- ^ a b Houk, Nancy (1979), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 3, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, Bibcode:1982mcts.book.....H.
- ^ Gontcharov, G. A. (November 2006), "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system", Astronomy Letters, 32 (11): 759–771, arXiv:1606.08053, Bibcode:2006AstL...32..759G, doi:10.1134/S1063773706110065, S2CID 119231169.
- ^ a b c 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 Hauck, B.; Curchod, A. (December 1980), "Properties of AM stars in the Geneva photometric system", Astronomy and Astrophysics, 92 (3): 289–295, Bibcode:1980A&A....92..289H.
- ^ a b c d e Stassun K.G.; et al. (October 2019), "The revised TESS Input Catalog and Candidate Target List", The Astronomical Journal, 158 (4): 138, arXiv:1905.10694, Bibcode:2019AJ....158..138S, doi:10.3847/1538-3881/ab3467, S2CID 166227927.
- ^ "zet02 Ant". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2012-06-27.
- ^ Renson, P.; Manfroid, J. (May 2009), "Catalogue of Ap, HgMn and Am stars", Astronomy and Astrophysics, 498 (3): 961–966, Bibcode:2009A&A...498..961R, doi:10.1051/0004-6361/200810788.