Astronomy:Nu Piscium
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| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Pisces[1] |
| Right ascension | 01h 41m 25.89414s[2] |
| Declination | +05° 29′ 15.4018″[2] |
| Apparent magnitude (V) | 4.44[3] |
| Characteristics | |
| Evolutionary stage | red giant branch[2] |
| Spectral type | K3 IIIb[3] |
| B−V color index | 1.37[3] |
| Variable type | Oscillating Red Giant |
| Astrometry | |
| Radial velocity (Rv) | 0.6±0.18[2] km/s |
| Proper motion (μ) | RA: −23.323[2] mas/yr Dec.: 3.505[2] mas/yr |
| Parallax (π) | 8.9275 ± 0.1567[2] mas |
| Distance | 365 ± 6 ly (112 ± 2 pc) |
| Absolute magnitude (MV) | −0.78[1] |
| Details | |
| ν Psc A | |
| Mass | 1.66[3] M☉ |
| Radius | 34.58+0.81 −0.83[4] R☉ |
| Luminosity | 380[3] L☉ |
| Surface gravity (log g) | 1.91[5] cgs |
| Temperature | 4,154[3] K |
| Metallicity [Fe/H] | −0.16[5] dex |
| Age | 3.41[3] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
Nu Piscium (ν Piscium) is an orange-hued binary star[7] system in the zodiac constellation of Pisces. Prior to the formation of the modern constellation boundaries in 1930, it was designated 51 Ceti in the Cetus constellation.[8] Nu Piscium is visible to the naked eye, having a combined apparent visual magnitude of 4.44.[3] Based upon an annual parallax shift of 8.93 mas as seen from Earth,[2] it is located about 365 light years from the Sun.
The primary, component A, is an evolved, K-type giant star with a stellar classification of K3 IIIb.[3] It is a weak barium star, indicating that the atmosphere was previously enriched by accretion of s-process elements from what is now a white dwarf companion.[9] The giant has 1.66[3] times the mass of the Sun and has expanded to about 35[4] times the Sun's radius. It is about 3.4 billion years old and is radiating 380 times the Sun's luminosity from its photosphere at an effective temperature of 4,154 K.[3]
In 2026 the star was discovered to be an ORG (Oscillating Red Giant) variable by the Italian amateur research group GrAG (Gruppo Astrofili Galileo Galilei APS).[10]
Naming
In Chinese, 外屏 (Wài Píng), meaning Outer Fence, refers to an asterism consisting of ν Piscium, δ Piscium, ε Piscium, ζ Piscium, μ Piscium, ξ Piscium and α Piscium. Consequently, the Chinese name for ν Piscium itself is 外屏五 (Wài Píng wu, English: the Fifth Star of Outer Fence.)[11]
References
- ↑ 1.0 1.1 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331. doi:10.1134/S1063773712050015. Bibcode: 2012AstL...38..331A. XHIP record for this object at VizieR.
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940 Gaia DR3 record for this source at VizieR.
- ↑ 3.00 3.01 3.02 3.03 3.04 3.05 3.06 3.07 3.08 3.09 3.10 Luck, R. Earle (September 2015), "Abundances in the Local Region. I. G and K Giants", The Astronomical Journal 150 (3): 23, doi:10.1088/0004-6256/150/3/88, 88, Bibcode: 2015AJ....150...88L.
- ↑ 4.0 4.1 Baines, Ellyn K.; Thomas Armstrong, J.; Clark, James H.; Gorney, Jim; Hutter, Donald J.; Jorgensen, Anders M.; Kyte, Casey; Mozurkewich, David et al. (2021). "Angular Diameters and Fundamental Parameters of Forty-four Stars from the Navy Precision Optical Interferometer". The Astronomical Journal 162 (5): 198. doi:10.3847/1538-3881/ac2431. Bibcode: 2021AJ....162..198B.
- ↑ 5.0 5.1 Prugniel, Ph.; Vauglin, I.; Koleva, M. (July 2011), "The atmospheric parameters and spectral interpolator for the MILES stars", Astronomy & Astrophysics 531: A165, doi:10.1051/0004-6361/201116769, Bibcode: 2011A&A...531A.165P.
- ↑ "nu. Psc". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=nu.+Psc.
- ↑ McDonald, I. et al. (2012), "Fundamental Parameters and Infrared Excesses of Hipparcos Stars", Monthly Notices of the Royal Astronomical Society 427 (1): 343–57, doi:10.1111/j.1365-2966.2012.21873.x, Bibcode: 2012MNRAS.427..343M.
- ↑ Wagman, M. (August 1987), "Flamsteed's Missing Stars", Journal for the History of Astronomy 18 (3): 215, doi:10.1177/002182868701800305, Bibcode: 1987JHA....18..209W.
- ↑ Gomez, A. E. et al. (1997), "Absolute magnitudes and kinematics of barium stars", Astronomy and Astrophysics 319: 881, Bibcode: 1997A&A...319..881G.
- ↑ "VSX : Detail for nu. Psc". https://vsx.aavso.org/index.php?view=detail.top&oid=10875740.
- ↑ (in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 5 月 19 日
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