Summary
Zeta Pyxidis (ζ Pyxidis) is a wide binary star[9] system in the southern constellation of Pyxis. It is visible to the naked eye with a combined apparent visual magnitude of +4.88.[2] Based upon an annual parallax shift of 13.35 mas as seen from Earth,[1] it is located around 244 light years from the Sun.
  | |
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Pyxis |
| Right ascension | 08h 39m 42.47410s[1] |
| Declination | −29° 33′ 39.8989″[1] |
| Apparent magnitude (V) | +4.88[2] (4.97 + 9.59)[3] |
| Characteristics | |
| Spectral type | G6 IIIb CN-0.5[4] |
| B−V color index | +0.90[2] |
| Astrometry | |
| Radial velocity (Rv) | −30.10[5] km/s |
| Proper motion (μ) | RA: −24.81[1] mas/yr Dec.: −90.96[1] mas/yr |
| Parallax (π) | 13.35 ± 0.23 mas[1] |
| Distance | 244 ± 4 ly (75 ± 1 pc) |
| Absolute magnitude (MV) | +0.49[6] |
| Details | |
| ζ Pyx A | |
| Mass | 1.96[5] M☉ |
| Luminosity | 69[5] L☉ |
| Surface gravity (log g) | 2.72±0.06[7] cgs |
| Temperature | 4,876±8[5] K |
| Metallicity [Fe/H] | −0.43±0.02[7] dex |
| Age | 1.88[5] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
The yellow-hued primary, component A, is an evolved G-type giant star with a stellar classification of G6 IIIb CN-0.5,[4] where the suffix notation indicating it has anomalously weak lines of cyanogen. At the age of 1.88 billion years,[5] is a red clump star that is generating energy through the fusion of helium at its core.[10] The primary has nearly double the mass of the Sun and is radiating 69 times the Sun's luminosity from its photosphere at an effective temperature of 4,876 K.[5]
The companion, component B, is a magnitude 9.59 star at an angular separation of 52.20 arc seconds along a position angle of 61°, as of 2010.[3]
References edit
- ^ a b c d e f 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 c Cousins, A. W. J.; et al. (1966), "Photoelectric magnitudes and colours of southern stars, II", Royal Observatory Bulletins, 121: 1, Bibcode:1966RGOB..121....1C.
- ^ a b Mason, B. D.; et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal, 122 (6): 3466, Bibcode:2001AJ....122.3466M, doi:10.1086/323920
- ^ a b Keenan, Philip C.; McNeil, Raymond C. (1989), "The Perkins catalog of revised MK types for the cooler stars", Astrophysical Journal Supplement Series, 71: 245, Bibcode:1989ApJS...71..245K, doi:10.1086/191373, S2CID 123149047.
- ^ a b c d e f g 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.
- ^ 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 Alves, S.; et al. (April 2015), "Determination of the spectroscopic stellar parameters for 257 field giant stars", Monthly Notices of the Royal Astronomical Society, 448 (3): 2749–2765, arXiv:1503.02556, Bibcode:2015MNRAS.448.2749A, doi:10.1093/mnras/stv189, S2CID 119217930.
- ^ "zet Pyx". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-07-16.
- ^ 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.
- ^ Alves, David R. (August 2000), "K-Band Calibration of the Red Clump Luminosity", The Astrophysical Journal, 539 (2): 732–741, arXiv:astro-ph/0003329, Bibcode:2000ApJ...539..732A, doi:10.1086/309278, S2CID 16673121.