Eta Antliae (η Ant, η Antliae) is the Bayer designation for a double star in the southern constellation of Antlia. The brighter component has an apparent visual magnitude of 5.222,[2] making it visible to the naked eye. Parallax measurements of the system yield a distance estimate of 108.5 light-years (33.3 parsecs) from Earth.[1]
  | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Antlia |
| Right ascension | 09h 58m 52.27552s[1] |
| Declination | −35° 53′ 27.4977″[1] |
| Apparent magnitude (V) | 5.222[2] |
| Characteristics | |
| Spectral type | F1 V[3] |
| U−B color index | +0.068[2] |
| B−V color index | +0.333[2] |
| Astrometry | |
| Radial velocity (Rv) | +30[4] km/s |
| Proper motion (μ) | RA: −89.782[1] mas/yr Dec.: −16.245[1] mas/yr |
| Parallax (π) | 30.0606 ± 0.1080 mas[1] |
| Distance | 108.5 ± 0.4 ly (33.3 ± 0.1 pc) |
| Absolute magnitude (MV) | +2.62[5] |
| Details | |
| η Ant A | |
| Mass | 1.55[6] M☉ |
| Radius | 1.72[1] R☉ |
| Luminosity | 6.6[6] L☉ |
| Surface gravity (log g) | 3.94[3] cgs |
| Temperature | 7,132[3] K |
| Metallicity [Fe/H] | −0.20[3] dex |
| Age | 0.9[6] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
| Database references | |
| SIMBAD | data |
The main component has a stellar classification of F1 V,[3] which indicates that it is an F-type main sequence star. This star has 55% more mass than the Sun.[6] It shines with 6.6[6] times the Sun's luminosity at an effective temperature of 7,132 K.[3] This heat gives it the yellow-white glow of an F-type star.[8] It has a faint companion located 31 arcseconds away with an apparent magnitude of +11.3. Most likely this pair form a binary star system.[9]
References
edit- ^ a b c d e f g 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 Gutierrez-Moreno, Adelina; et al. (1966), "A System of photometric standards", Publications of the Department of Astronomy University of Chile, 1, Publicaciones Universidad de Chile, Department de Astronomy: 1–17, Bibcode:1966PDAUC...1....1G.
- ^ a b c d e f Gray, R. O.; et al. (July 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): 161–170, arXiv:astro-ph/0603770, Bibcode:2006AJ....132..161G, doi:10.1086/504637, S2CID 119476992.
- ^ 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.
- ^ 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 c d e Mallik, Sushma V.; Parthasarathy, M.; Pati, A. K. (October 2003), "Lithium and rotation in F and G dwarfs and subgiants", Astronomy and Astrophysics, 409 (1): 251–261, Bibcode:2003A&A...409..251M, doi:10.1051/0004-6361:20031084.
- ^ "* eta Ant". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2012-06-28.
{{cite web}}: CS1 maint: postscript (link) - ^ "The Colour of Stars", Australia Telescope, Outreach and Education, Commonwealth Scientific and Industrial Research Organisation, December 21, 2004, archived from the original on 2012-03-18, retrieved 2012-01-16.
- ^ 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.