Wikipedia
Phi1 Orionis
Phi1 Orionis is a binary star system in the constellation Orion, positioned less than a degree to the south of Meissa.[10] It is visible to the naked eye with an apparent visual magnitude of 4.42.[2] The distance to this system, based upon an annual parallax shift of 3.0 mas,[1] is around 1,090 light-years.
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Orion |
| Right ascension | 05h 34m 49.23804s[1] |
| Declination | +09° 29′ 22.4878″[1] |
| Apparent magnitude (V) | 4.42[2] |
| Characteristics | |
| Spectral type | B0 III[3] |
| U−B color index | −0.97[2] |
| B−V color index | −0.15[2] |
| Astrometry | |
| Radial velocity (Rv) | +33.2[4] km/s |
| Proper motion (μ) | RA: +0.27[1] mas/yr Dec.: −2.26[1] mas/yr |
| Parallax (π) | 3.00 ± 0.25 mas[1] |
| Distance | 1,090 ± 90 ly (330 ± 30 pc) |
| Absolute magnitude (MV) | −3.53±0.30 |
| Orbit[5] | |
| Period (P) | 3,068.03 d |
| Eccentricity (e) | 0.22 |
| Periastron epoch (T) | 2418051.8 JD |
| Argument of periastron (ω) (secondary) | 105° |
| Semi-amplitude (K1) (primary) | 13.3 km/s |
| Details[6] | |
| Mass | 15.5±1.1 M☉ |
| Radius | 6.3±1.0 R☉ |
| Luminosity | 28,840 L☉ |
| Surface gravity (log g) | 4.05±0.10 cgs |
| Temperature | 30,000±300 K |
| Rotational velocity (v sin i) | 20[7] km/s |
| Age | 7.2±0.8[8] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is a single-lined[6] spectroscopic binary star system with an orbital period of 3,068 days and an eccentricity of 0.22.[5] It is a member of the young Lambda Orionis cluster[11] and is roughly 7 million years old.[8] The primary component is a B-type giant star with a stellar classification of B0 III.[3] It has over 15 times the mass of the Sun and around 6.3 times the Sun's radius.[6] Nothing is known about the secondary companion. It does not contribute a significant amount of light to the combined spectrum.[6]
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 d Murdin, P.; Penston, M. V. (December 1977), "The Lambda Orionis association", Monthly Notices of the Royal Astronomical Society, 181 (4): 657–665, Bibcode:1977MNRAS.181..657M, doi:10.1093/mnras/181.4.657.
- ^ a b Levato, H. (January 1975), "Rotational velocities and spectral types for a sample of binary systems", Astronomy and Astrophysics Supplement Series, 19: 91–99, Bibcode:1975A&AS...19...91L.
- ^ Wilson, R. E. (1953), "General Catalogue of Stellar Radial Velocities", Carnegie Institute Washington D.C. Publication, Carnegie Institute of Washington, D.C., Bibcode:1953GCRV..C......0W.
- ^ a b Pourbaix, D.; et al. (2004), "SB9: The ninth catalogue of spectroscopic binary orbits", Astronomy & Astrophysics, 424 (2): 727–732, arXiv:astro-ph/0406573, Bibcode:2004A&A...424..727P, doi:10.1051/0004-6361:20041213, S2CID 119387088.
- ^ a b c d Nieva, María-Fernanda; Przybilla, Norbert (2014), "Fundamental properties of nearby single early B-type stars", Astronomy & Astrophysics, 566: A7, arXiv:1412.1418, Bibcode:2014A&A...566A...7N, doi:10.1051/0004-6361/201423373, S2CID 119227033.
- ^ Simón-Díaz, S.; Herrero, A. (2014), "The IACOB project. I. Rotational velocities in northern Galactic O- and early B-type stars revisited. The impact of other sources of line-broadening", Astronomy & Astrophysics, 562: A135, arXiv:1311.3360, Bibcode:2014A&A...562A.135S, doi:10.1051/0004-6361/201322758, S2CID 119278062.
- ^ a b Tetzlaff, N.; et al. (2011), "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun", Monthly Notices of the Royal Astronomical Society, 410 (1): 190–200, arXiv:1007.4883, Bibcode:2011MNRAS.410..190T, doi:10.1111/j.1365-2966.2010.17434.x, S2CID 118629873.
- ^ "phi01 Ori". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2016-11-29.
{{cite web}}: CS1 maint: postscript (link) - ^ O'Meara, Stephen James (2007), Deep-Sky Companions: Hidden Treasures, Cambridge University Press, p. 146, ISBN 978-1139463737.
- ^ Hernández, Jesús; Calvet, Nuria; Hartmann, L.; Muzerolle, J.; Gutermuth, R.; Stauffer, J. (December 2009), "Spitzer Observations of the λ Orionis Cluster. I. The Frequency of Young Debris Disks at 5 Myr", The Astrophysical Journal, 707 (1): 705–715, arXiv:0910.3884, Bibcode:2009ApJ...707..705H, doi:10.1088/0004-637X/707/1/705, S2CID 17546989.
External links edit
- Kaler, James B. (February 10, 2012), "Phi-1 Orionis", Stars, University of Illinois, retrieved 2016-11-30.