Astronomy:Phi2 Orionis
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Short description: Star in the constellation Orion
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| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Orion |
| Right ascension | 05h 36m 54.389s[1] |
| Declination | +09° 17′ 26.42″[1] |
| Apparent magnitude (V) | 4.081[2] |
| Characteristics | |
| Evolutionary stage | Yellow giant |
| Spectral type | G8 III-IV[3] |
| U−B color index | +0.618[2] |
| B−V color index | +0.966[2] |
| Astrometry | |
| Radial velocity (Rv) | 99.03±0.18[1] km/s |
| Proper motion (μ) | RA: +98.301[1] mas/yr Dec.: −305.022[1] mas/yr |
| Parallax (π) | 28.6722 ± 0.1859[1] mas |
| Distance | 113.8 ± 0.7 ly (34.9 ± 0.2 pc) |
| Absolute magnitude (MV) | +1.33±0.07[4] |
| Details | |
| Mass | 1.07±0.04[5] M☉ |
| Radius | 8.45±0.06[6] R☉ |
| Luminosity | 29.8±0.4[7] L☉ |
| Surface gravity (log g) | 3.00±0.02[5] cgs |
| Temperature | 4,703±11[7] K |
| Metallicity [Fe/H] | −0.56±0.02[5] dex |
| Rotational velocity (v sin i) | 1.91±0.53[5] km/s |
| Age | 6.91±1.04[5] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
Phi2 Orionis is a star in the constellation Orion, where it forms a small triangle on the celestial sphere with the nearby Meissa and Phi1 Orionis.[9] This star is visible to the naked eye with an apparent visual magnitude of 4.081.[2] Based upon an annual parallax shift of 28.67 mas,[7] it is located around 114 light-years from the Sun.
This is an evolved G-type star of stellar classification G8 III-IV,[3] which means that it is in an evolutionary stage between a subgiant (IV) and a giant star (III). It is estimated to be 6.9 billion years old, has 1.07 times the mass of the Sun,[5] but has expanded to 8 times the Sun's radius. The star shines with 30 times the solar luminosity from its outer atmosphere at an effective temperature of 4,700 K.[7]
References
- ↑ 1.0 1.1 1.2 1.3 1.4 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 Frasca, A. et al. (December 2009), "REM near-IR and optical photometric monitoring of pre-main sequence stars in Orion. Rotation periods and starspot parameters", Astronomy and Astrophysics 508 (3): 1313–1330, doi:10.1051/0004-6361/200913327, Bibcode: 2009A&A...508.1313F.
- ↑ Charbonnel, Corinne et al. (April 1998), "Mixing processes during the evolution of red giants with moderate metal deficiencies: the role of molecular-weight barriers", Astronomy and Astrophysics 332: 204–214, Bibcode: 1998A&A...332..204C.
- ↑ 5.0 5.1 5.2 5.3 5.4 5.5 Jofré, E. et al. (2015), "Stellar parameters and chemical abundances of 223 evolved stars with and without planets", Astronomy & Astrophysics 574: A50, doi:10.1051/0004-6361/201424474, A50, Bibcode: 2015A&A...574A..50J.
- ↑ Anugu, Narsireddy; Monnier, John D.; Mérand, Antoine; Flores, Becky; Gallenne, Alexandre; Gies, Douglas R.; Gutierrez, Mayra; Klement, Robert et al. (2026-07-27), "Empirical H- and K-band Limb Darkening for 31 CHARA Stars: A Near-Infrared Benchmark for Stellar-Atmosphere Models", The Astronomical Journal.
- ↑ 7.0 7.1 7.2 7.3 Baines, Ellyn K.; Clark, James H., III; Schmitt, Henrique R.; Stone, Jordan M.; von Braun, Kaspar (2023-12-01), "33 New Stellar Angular Diameters from the NPOI, and Nearly 180 NPOI Diameters as an Ensemble", The Astronomical Journal 166 (6): 268, doi:10.3847/1538-3881/ad08be, ISSN 0004-6256, Bibcode: 2023AJ....166..268B.
- ↑ "phi02 Ori". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=phi02+Ori.
- ↑ Kaler, James B. (February 10, 2012), "Phi-1 Orionis", Stars (University of Illinois), http://stars.astro.illinois.edu/sow/phi1ori.html, retrieved 2016-11-30.
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