10 Canis Majoris
10 Canis Majoris is a single[13] variable star in the southern constellation of Canis Major,[12] located roughly 1,800 light years away from the Sun.[1] It has the variable star designation FT Canis Majoris; 10 Canis Majoris is the Flamsteed designation. This body is visible to the naked eye as a faint, blue-white hued star with a baseline apparent visual magnitude of 5.23.[2] It is moving away from the Earth with a heliocentric radial velocity of +34 km/s.[6]
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Canis Major |
Right ascension | 06h 44m 28.46789s[1] |
Declination | −31° 04′ 13.8821″[1] |
Apparent magnitude (V) | 5.23[2] (5.13–5.44)[3] |
Characteristics | |
Spectral type | B2 V[4] or B2 IIIe[5] |
B−V color index | −0.127±0.005[2] |
Variable type | Be[3] |
Astrometry | |
Radial velocity (Rv) | +34.0±4.2[6] km/s |
Proper motion (μ) | RA: −3.938[1] mas/yr Dec.: +3.549[1] mas/yr |
Parallax (π) | 1.7924 ± 0.1371 mas |
Distance | 1,800 ± 100 ly (560 ± 40 pc) |
Details | |
Mass | 19.2±0.1[7] M☉ |
Radius | 10.0[8] R☉ |
Luminosity | 44,463+35,336 −19,689[9] L☉ |
Surface gravity (log g) | 3.76±0.17[9] cgs |
Temperature | 25,350±1,030[9] K |
Rotation | 2.63 d[10] |
Rotational velocity (v sin i) | 205±5[11] km/s |
Age | 8.2±0.1[7] Myr |
Other designations | |
Database references | |
SIMBAD | data |
This is a massive Be star[8] with a stellar classification of B2 V,[4] matching a B-type main-sequence star. Hiltner et al. (1969) found a giant class of B2 IIIe,[5] which is still in use with some studies.[13][3] The star is spinning rapidly with a projected rotational velocity of 205 km/s[11] and a rotational period of 2.63 days.[10] This is giving it an oblate shape with an equatorial bulge that is 5% larger than the polar radius.[14] The axis of rotation is inclined by an angle of 45° to the line of sight from the Earth.[8] Samus et al. (2017) classify it as a Be-type variable star that ranges from a peak visual magnitude of 5.13 down to 5.44 with a rotationally-modulated period of 2.63 days.[3][10]
10 Canis Majoris is 8.2[7] million years old with 19.2[7] times the mass of the Sun and 10[8] times the Sun's radius. It is radiating around 44,000[9] times the luminosity of the Sun from its photosphere at an effective temperature of 25,000 K.[9] There is a magnitude 12.58 visual companion at an angular separation of 37.3″ along a position angle of 99°, as of 2015.[15]
References
- Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- 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.
- Samus, N. N.; et al. (2017), "General Catalogue of Variable Stars", Astronomy Reports, 5.1, 61 (1): 80–88, Bibcode:2017ARep...61...80S, doi:10.1134/s1063772917010085, S2CID 125853869.
- Houk, Nancy (1979), Michigan catalogue of two-dimensional spectral types for the HD stars, 3, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, Bibcode:1982mcts.book.....H
- Hiltner, W. A.; et al. (July 1969), "MK Spectral Types for Bright Southern OB Stars", Astrophysical Journal, 157: 313–326, Bibcode:1969ApJ...157..313H, doi:10.1086/150069.
- 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.
- Tetzlaff, N.; et al. (January 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.
- Zorec, J.; et al. (July 2007), "Be star disc characteristics near the central object", Astronomy and Astrophysics, 470 (1): 239–247, Bibcode:2007A&A...470..239Z, doi:10.1051/0004-6361:20066615.
- Zorec, J.; et al. (November 2016), "Critical study of the distribution of rotational velocities of Be stars. I. Deconvolution methods, effects due to gravity darkening, macroturbulence, and binarity", Astronomy & Astrophysics, 595: 26, Bibcode:2016A&A...595A.132Z, doi:10.1051/0004-6361/201628760.
- Balona, L. A.; et al. (February 1992), "Intensive photometry of southern Be variables. II - Summer objects", Astronomy and Astrophysics Supplement Series, 92 (3): 533–563, Bibcode:1992A&AS...92..533B.
- Chauville, J.; Zorec, J.; Ballereau, D.; Morrell, N.; Cidale, L.; Garcia, A. (November 2001), "High and intermediate-resolution spectroscopy of Be stars 4481 lines", Astronomy and Astrophysics, 378: 861–882, Bibcode:2001A&A...378..861C, doi:10.1051/0004-6361:20011202
- "10 CMa". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved April 27, 2019.
- Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
- van Belle, Gerard T. (March 2012), "Interferometric observations of rapidly rotating stars", The Astronomy and Astrophysics Review, 20 (1): 51, arXiv:1204.2572, Bibcode:2012A&ARv..20...51V, doi:10.1007/s00159-012-0051-2, S2CID 119273474.
- Mason, B. D.; et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal, 122 (6): 3466–3471, Bibcode:2001AJ....122.3466M, doi:10.1086/323920