Astronomy:10 Canis Majoris
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Canis Major |
| Right ascension | 06h 44m 28.46710s[2] |
| Declination | −31° 04′ 13.8923″[2] |
| Apparent magnitude (V) | 5.23[3] (5.13–5.44)[4] |
| Characteristics | |
| Spectral type | B2 V[5] or B2 IIIe[6] |
| B−V color index | −0.127±0.005[3] |
| Variable type | Be[4] |
| Astrometry | |
| Radial velocity (Rv) | +34.0±4.2[7] km/s |
| Proper motion (μ) | RA: −3.286[2] mas/yr Dec.: +4.201[2] mas/yr |
| Parallax (π) | 1.6454 ± 0.0722[2] mas |
| Distance | 1,980 ± 90 ly (610 ± 30 pc) |
| Details | |
| Mass | 19.2±0.1[8] M☉ |
| Radius | 10.0[9] R☉ |
| Luminosity | 44,463+35,336 −19,689[10] L☉ |
| Surface gravity (log g) | 3.76±0.17[10] cgs |
| Temperature | 25,350±1,030[10] K |
| Rotation | 2.63 d[11] |
| Rotational velocity (v sin i) | 205±5[12] km/s |
| Age | 8.2±0.1[8] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
10 Canis Majoris is a single[14] variable star in the southern constellation of Canis Major,[13] located roughly 1,980 light years away from the Sun.[2] 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.[3] It is moving away from the Earth with a heliocentric radial velocity of +34 km/s.[7]
This is a massive Be star[9] with a stellar classification of B2 V,[5] matching a B-type main-sequence star. Hiltner et al. (1969) found a giant class of B2 IIIe,[6] which is still in use with some studies.[14][4] The star is spinning rapidly with a projected rotational velocity of 205 km/s[12] and a rotational period of 2.63 days.[11] This is giving it an oblate shape with an equatorial bulge that is 5% larger than the polar radius.[15] The axis of rotation is inclined by an angle of 45° to the line of sight from the Earth.[9] 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.[4][11]
10 Canis Majoris is 8.2[8] million years old with 19.2[8] times the mass of the Sun and 10[9] times the Sun's radius. It is radiating around 44,000[10] times the luminosity of the Sun from its photosphere at an effective temperature of 25,000 K.[10] There is a magnitude 12.58 visual companion at an angular separation of 37.3″ along a position angle of 99°, as of 2015.[16]
References
- ↑ Lefèvre, L.; Marchenko, S. V.; Moffat, A. F. J.; Acker, A. (November 2009), "A systematic study of variability among OB-stars based on HIPPARCOS photometry", Astronomy & Astrophysics 507 (2): 1141–1201, doi:10.1051/0004-6361/200912304, Bibcode: 2009A&A...507.1141L.
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 Brown, A. G. A. (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics 649: A1. doi:10.1051/0004-6361/202039657. Bibcode: 2021A&A...649A...1G. Gaia EDR3 record for this source at VizieR.
- ↑ 3.0 3.1 3.2 Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters 38 (5): 331, doi:10.1134/S1063773712050015, Bibcode: 2012AstL...38..331A.
- ↑ 4.0 4.1 4.2 4.3 Samus, N. N. et al. (2017), "General Catalogue of Variable Stars", Astronomy Reports, 5.1 61 (1): 80–88, doi:10.1134/s1063772917010085, Bibcode: 2017ARep...61...80S.
- ↑ 5.0 5.1 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.
- ↑ 6.0 6.1 Hiltner, W. A. et al. (July 1969), "MK Spectral Types for Bright Southern OB Stars", Astrophysical Journal 157: 313–326, doi:10.1086/150069, Bibcode: 1969ApJ...157..313H.
- ↑ 7.0 7.1 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, doi:10.1051/0004-6361/201219219, A61, Bibcode: 2012A&A...546A..61D.
- ↑ 8.0 8.1 8.2 8.3 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, doi:10.1111/j.1365-2966.2010.17434.x, Bibcode: 2011MNRAS.410..190T.
- ↑ 9.0 9.1 9.2 9.3 Zorec, J. et al. (July 2007), "Be star disc characteristics near the central object", Astronomy and Astrophysics 470 (1): 239–247, doi:10.1051/0004-6361:20066615, Bibcode: 2007A&A...470..239Z.
- ↑ 10.0 10.1 10.2 10.3 10.4 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, doi:10.1051/0004-6361/201628760, Bibcode: 2016A&A...595A.132Z.
- ↑ 11.0 11.1 11.2 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.
- ↑ 12.0 12.1 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, doi:10.1051/0004-6361:20011202, Bibcode: 2001A&A...378..861C.
- ↑ 13.0 13.1 "10 CMa". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=10+CMa.
- ↑ 14.0 14.1 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, doi:10.1111/j.1365-2966.2008.13596.x, Bibcode: 2008MNRAS.389..869E.
- ↑ van Belle, Gerard T. (March 2012), "Interferometric observations of rapidly rotating stars", The Astronomy and Astrophysics Review 20 (1): 51, doi:10.1007/s00159-012-0051-2, Bibcode: 2012A&ARv..20...51V.
- ↑ Mason, B. D. et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal 122 (6): 3466–3471, doi:10.1086/323920, Bibcode: 2001AJ....122.3466M.
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