3 Monocerotis

3 Monocerotis is a binary star[3] system in the equatorial constellation of Monoceros, located approximately 780 light years away from the Sun based on parallax.[1] It is visible to the naked eye as a faint, blue-white hued star with a combined apparent visual magnitude of 4.92.[2] The system is moving further from the Earth with a heliocentric radial velocity of +39 km/s.[6]

3 Monocerotis

Location of 3 Monocerotis (circled)
Observation data Epoch J2000      Equinox J2000
Constellation	Monoceros
Right ascension	06^h 01^m 50.42241^s[1]
Declination	−10° 35′ 52.5565″[1]
Apparent magnitude (V)	4.92[2] (4.98 + 8.25)[3]
Characteristics
Spectral type	B5 III[4]
U−B color index	−0.58[5]
B−V color index	−0.12[5]
Astrometry
Radial velocity (Rv)	+39.00[6] km/s
Absolute magnitude (MV)	−1.94[2]
A
Proper motion (μ)	RA: −8.282[7] mas/yr Dec.: 4.385[7] mas/yr
Parallax (π)	4.5717 ± 0.3115[7] mas
Distance	710 ± 50 ly (220 ± 10 pc)
B
Proper motion (μ)	RA: 6.990[8] mas/yr Dec.: 4.574[8] mas/yr
Parallax (π)	3.1006 ± 0.0960[8] mas
Distance	1,050 ± 30 ly (323 ± 10 pc)
Details
3 Mon A
Mass	5.85[9] M☉
Radius	4.5[10] R☉
Luminosity	1,105[2] L☉
Temperature	15,000[9] K
Metallicity [Fe/H]	0.00[11] dex
Rotational velocity (v sin i)	45[12] km/s
Other designations
3 Mon, BD−10°1349, GC 7631, HD 40967, HIP 28574, HR 2128, SAO 151037, CCDM J06018-1036, WDS J06018-1036[13]
Database references
SIMBAD	data

The magnitude 4.98 primary, designated component A, has a stellar classification of B5 III,[4] matching an evolved blue giant star. It has 5.85[9] times the mass of the Sun and is radiating 1,105[2] times the Sun's luminosity from its photosphere at an effective temperature of 15,000 K.[9] The companion, component B, is magnitude 7.96 with an angular separation of 1.9″ from the primary.[14]

References

1. Van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. Vizier catalog entry
2. 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. Vizier catalog entry
3. 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.
4. Hoffleit, D.; Warren, W. H. (1995). "VizieR Online Data Catalog: Bright Star Catalogue, 5th Revised Ed. (Hoffleit+, 1991)". VizieR On-line Data Catalog: V/50. Originally Published in: 1964BS....C......0H. 5050. Bibcode:1995yCat.5050....0H.
5. Mallama, A. (2014). "Sloan Magnitudes for the Brightest Stars". The Journal of the American Association of Variable Star Observers. 42: 443. Bibcode:2014JAVSO..42..443M.Vizier catalog entry
6. Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065.
7. 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.
8. 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.
9. Hohle, M.M.; Neuhäuser, R.; Schutz, B.F. (2010). "Masses and luminosities of O- and B-type stars and red supergiants". Astronomische Nachrichten. 331 (4): 349. arXiv:1003.2335. Bibcode:2010AN....331..349H. doi:10.1002/asna.200911355. Vizier catalog entry
10. Pasinetti Fracassini, L. E.; et al. (February 2001). "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)". Astronomy and Astrophysics (Third ed.). 367 (2): 521–524. arXiv:astro-ph/0012289. Bibcode:2001A&A...367..521P. doi:10.1051/0004-6361:20000451.
11. Gontcharov, G. A. (2012). "Dependence of kinematics on the age of stars in the solar neighborhood". Astronomy Letters. 38 (12): 771. arXiv:1606.08814. Bibcode:2012AstL...38..771G. doi:10.1134/S1063773712120031. Vizier catalog entry
12. Abt, Helmut A.; Levato, Hugo; Grosso, Monica (2002). "Rotational Velocities of B Stars". The Astrophysical Journal. 573: 359. Bibcode:2002ApJ...573..359A. doi:10.1086/340590.
13. "3 Mon". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-04-12.
14. Mason, Brian D.; Wycoff, Gary L.; Hartkopf, William I.; Douglass, Geoffrey G.; Worley, Charles E. (2001). "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog". The Astronomical Journal. 122 (6): 3466. Bibcode:2001AJ....122.3466M. doi:10.1086/323920. Vizier catalog entry