Astronomy:Gamma Piscium
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| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Pisces |
| Right ascension | 23h 17m 09.937s[1] |
| Declination | +03° 16′ 56.25″[1] |
| Apparent magnitude (V) | 3.699[2] |
| Characteristics | |
| Evolutionary stage | Horizontal branch[3] |
| Spectral type | G8 III[4] |
| U−B color index | +0.572 [2] |
| B−V color index | +0.924[2] |
| Astrometry | |
| Radial velocity (Rv) | −13.6[5] km/s |
| Proper motion (μ) | RA: 759.268[1] mas/yr Dec.: 17.568[1] mas/yr |
| Parallax (π) | 24.1958 ± 0.2967[6] mas |
| Distance | 135 ± 2 ly (41.3 ± 0.5 pc) |
| Absolute magnitude (MV) | 0.68±0.08[7] |
| Details | |
| Mass | 0.97±0.12[3] M☉ |
| Radius | 11.28±0.10[4] R☉ |
| Luminosity | 62.7±3.3[4] L☉ |
| Surface gravity (log g) | 2.43 ± 0.06[7] cgs |
| Temperature | 4833±62[4] K |
| Metallicity [Fe/H] | −0.51[7] dex |
| Age | 4.58±3.10[4] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
Gamma Piscium (γ Piscium) is a star approximately 135 light years away from Earth in the zodiac constellation of Pisces. It is a yellow star with a spectral type of G8 III, meaning it has a surface temperature of 4,833 K and is a giant star. It is slightly cooler than the Sun, yet it is 11[4] solar radii in size and shines with the light of 63 Suns.[4] The star is a member of the red clump, which means it is undergoing core helium fusion.[9] At an apparent magnitude of 3.7,[2] it is the second brightest star in the constellation Pisces, between Eta and Alpha.
Gamma Piscium moves across the sky at three-quarters of an arcsecond per year, which at 135 light years corresponds to 153 kilometers per second.[citation needed] This suggests it is a visitor from another part of the Milky Way Galaxy; in astronomical terms, it will quickly leave the vicinity of the Sun. Its metallicity is only one-fourth that of the Sun, and visitors from outside the thin disk that composes the Milky Way tend to be metal-poor. Gamma Piscium is part of the asterism known as the "circlet of Pisces."[10]
Naming
In Chinese, 霹靂 (Pī Lì), meaning Thunderbolt, refers to an asterism consisting of γ Piscium, β Piscium, θ Piscium, ι Piscium and ω Piscium. Consequently, the Chinese name for γ Piscium itself is 霹靂二 (Pī Lì èr, English: the Second Star of Thunderbolt.)[11]
Planetary system
In 2021, a gas giant planet was detected by the radial velocity method.[12]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | >1.34+0.02−0.31 MJ | 1.32+0.05−0.08 | 555.1+6.0−2.5 | 0.204+0.114−0.141 | — | — |
In fiction
In Frank Herbert's Dune series, Gamma Waiping (The Chinese name for Pisces) is the home system of Imperial House Corrino.[citation needed]
References
- ↑ 1.0 1.1 1.2 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.
- ↑ 2.0 2.1 2.2 2.3 Cousins, A. W. J. (1984), "Standardization of Broadband Photometry of Equatorial Standards", South African Astronomical Observatory Circulars 8: 59, Bibcode: 1984SAAOC...8...59C
- ↑ 3.0 3.1 Fuhrmann, Klaus; Chini, Rolf (January 2022), "On the Brightest Horizontal Branch Population II Star γ Piscium", Research Notes of the AAS 6 (1): 14, doi:10.3847/2515-5172/ac4a78, 14, Bibcode: 2022RNAAS...6...14F.
- ↑ 4.0 4.1 4.2 4.3 4.4 4.5 4.6 Baines, Ellyn K. et al. (2018). "Fundamental Parameters of 87 Stars from the Navy Precision Optical Interferometer". The Astronomical Journal 155 (1): 30. doi:10.3847/1538-3881/aa9d8b. Bibcode: 2018AJ....155...30B.
- ↑ Wielen, R. et al. (1999), "Sixth Catalogue of Fundamental Stars (FK6). Part I. Basic fundamental stars with direct solutions", Veroeffentlichungen des Astronomischen Rechen-Instituts Heidelberg (Astronomisches Rechen-Institut Heidelberg) 35 (35): 1, Bibcode: 1999VeARI..35....1W
- ↑ Van Leeuwen, Floor (2007). "Validation of the new Hipparcos reduction". Astronomy & Astrophysics 474 (2): 653–664. doi:10.1051/0004-6361:20078357. Bibcode: 2007A&A...474..653V. Vizier catalog entry
- ↑ 7.0 7.1 7.2 da Silva, L. et al. (November 2006), "Basic physical parameters of a selected sample of evolved stars", Astronomy and Astrophysics 458 (2): 609–623, doi:10.1051/0004-6361:20065105, Bibcode: 2006A&A...458..609D
- ↑ "* gam Psc". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=%2A+gam+Psc.
- ↑ Liu, Y. J. et al. (December 2007), "The abundances of nearby red clump giants", Monthly Notices of the Royal Astronomical Society 382 (2): 553–566, doi:10.1111/j.1365-2966.2007.11852.x, Bibcode: 2007MNRAS.382..553L.
- ↑ "SPACE.com -- SpaceWatch -- Pisces Rising". http://www.space.com/spacewatch/spacewatch_001113.html.
- ↑ (in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 8 日
- ↑ 12.0 12.1 Teng, Huan-Yu; Sato, Bun'ei; Takarada, Takuya; Omiya, Masashi; Harakawa, Hiroki; Izumiura, Hideyuki; Kambe, Eiji; Takeda, Yoichi et al. (2022), "Regular radial velocity variations in nine G- and K-type giant stars: Eight planets and one planet candidate", Publications of the Astronomical Society of Japan 74: 92–127, doi:10.1093/pasj/psab112
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