Omicron Arietis
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Aries |
| Right ascension | 02h 44m 32.97317s[1] |
| Declination | +15° 18′ 42.7085″[1] |
| Apparent magnitude (V) | +5.78[2] |
| Characteristics | |
| Spectral type | B9 Vn[3] |
| U−B color index | −0.21[4] |
| B−V color index | −0.01[4] |
| Astrometry | |
| Radial velocity (Rv) | −2.4±3.3[5] km/s |
| Proper motion (μ) | RA: +3.25[1] mas/yr Dec.: −14.87[1] mas/yr |
| Parallax (π) | 5.49 ± 0.32 mas[1] |
| Distance | 590 ± 30 ly (180 ± 10 pc) |
| Absolute magnitude (MV) | −0.51[6] |
| Details | |
| Mass | 3.45±0.09[7] M☉ |
| Radius | 3.1[8] R☉ |
| Luminosity | 248[7] L☉ |
| Temperature | 10,715[7] K |
| Rotational velocity (v sin i) | 225[9] km/s |
| Age | 286[10] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
Omicron Arietis, Latinised from ο Arietis, is the Bayer designation for a single,[2] blue-white-hued star in the northern constellation of Aries. It has an apparent visual magnitude of +5.78,[2] which means it is dimly visible to the naked eye. Based upon an annual parallax shift of 5.49 mas as seen from Earth,[1] it is located roughly 590 light-years from the Sun. At that distance, the visual magnitude of the star is diminished by an extinction factor of 0.22 due to interstellar dust.[10]
This is a B-type main-sequence star with a stellar classification of B9 Vn.[3] The 'n' suffix indicates that it has nebulous absorption lines in its spectrum, which are caused by the Doppler effect and rapid rotation. Indeed, it has a projected rotational velocity of 225 km/s.[9] The star has an estimated 3.45[7] times the mass of the Sun and about 3.1[8] times the Sun's radius. It is radiating energy from its photosphere at 248 times the Sun's luminosity with an effective temperature of 10,715 K.[7]
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 Eggleton, P. P.; Tokovinin, A. A. (2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
- ^ a b Cowley, A. (November 1972), "Spectral classification of the bright B8 stars", Astronomical Journal, 77: 750–755, Bibcode:1972AJ.....77..750C, doi:10.1086/111348.
- ^ a b Crawford, D. L. (February 1963), "U, b, v, and Hβ Photometry for the Bright B8- and B9-TYPE Stars", Astrophysical Journal, 137: 530, Bibcode:1963ApJ...137..530C, doi:10.1086/147526.
- ^ de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics, 546: 14, arXiv:1208.3048, Bibcode:2012A&A...546A..61D, doi:10.1051/0004-6361/201219219, S2CID 59451347, A61.
- ^ Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.
- ^ a b c d e Zorec, J.; Royer, F. (January 2012), "Rotational velocities of A-type stars. IV. Evolution of rotational velocities", Astronomy & Astrophysics, 537: A120, arXiv:1201.2052, Bibcode:2012A&A...537A.120Z, doi:10.1051/0004-6361/201117691, S2CID 55586789.
- ^ a b Pasinetti Fracassini, L. E.; et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)", Astronomy and Astrophysics, 367 (Third ed.): 5211–524, arXiv:astro-ph/0012289, Bibcode:2001A&A...367..521P, doi:10.1051/0004-6361:20000451, S2CID 425754.
- ^ a b Royer, F.; et al. (February 2007), "Rotational velocities of A-type stars. III. Velocity distributions", Astronomy and Astrophysics, 463 (2): 671–682, arXiv:astro-ph/0610785, Bibcode:2007A&A...463..671R, doi:10.1051/0004-6361:20065224, S2CID 18475298.
- ^ a b Gontcharov, G. A. (November 2012), "Spatial distribution and kinematics of OB stars", Astronomy Letters, 38 (11): 694–706, arXiv:1606.09028, Bibcode:2012AstL...38..694G, doi:10.1134/S1063773712110035, S2CID 119108982.
- ^ "omi Ari". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-09-28.
