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.[8] 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,[6] it is located around 114 light-years from the Sun.
  | |
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Orion |
| Right ascension | 05h 36m 54.389s[1] |
| Declination | +09° 17′ 26.417″[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 mas/yr[1] Dec.: −305.022 mas/yr[1] |
| Parallax (π) | 28.6722 ± 0.1859 mas[1] |
| Distance | 113.8 ± 0.7 ly (34.9 ± 0.2 pc)[1] |
| Absolute magnitude (MV) | +1.33±0.07[4] |
| Details[5] | |
| Mass | 1.07±0.04 M☉ |
| Radius | 8.22±0.07[6] R☉ |
| Luminosity | 29.8±0.04[6] L☉ |
| Surface gravity (log g) | 3.00±0.02 cgs |
| Temperature | 4,703±11[6] K |
| Metallicity [Fe/H] | −0.56±0.02 dex |
| Rotational velocity (v sin i) | 1.91±0.53 km/s |
| Age | 6.91±1.04 Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
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.[6]
References
edit- ^ a b c d e f Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
- ^ a b c d Cousins, A. W. J. (1984), "Standardization of Broadband Photometry of Equatorial Standards", South African Astronomical Observatory Circulars, 8: 59, Bibcode:1984SAAOC...8...59C.
- ^ a b 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, arXiv:0911.0760, Bibcode:2009A&A...508.1313F, doi:10.1051/0004-6361/200913327, S2CID 118361131.
- ^ 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, arXiv:astro-ph/9712207, Bibcode:1998A&A...332..204C.
- ^ a b Jofré, E.; et al. (2015), "Stellar parameters and chemical abundances of 223 evolved stars with and without planets", Astronomy & Astrophysics, 574: A50, arXiv:1410.6422, Bibcode:2015A&A...574A..50J, doi:10.1051/0004-6361/201424474, S2CID 53666931, A50.
- ^ a b c d e 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. Bibcode:2023AJ....166..268B. doi:10.3847/1538-3881/ad08be. ISSN 0004-6256.
{{cite journal}}: CS1 maint: multiple names: authors list (link) - ^ "phi02 Ori". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2016-11-30.
{{cite web}}: CS1 maint: postscript (link) - ^ Kaler, James B. (February 10, 2012), "Phi-1 Orionis", Stars, University of Illinois, retrieved 2016-11-30.