HD 57682

HD 57682

Location of HD 57682 (circled in red)
Observation data Epoch J2000.0       Equinox J2000.0
Constellation	Monoceros [1]
Right ascension	07h 22m 2.05s [2]
Declination	−08° 58′ 45.8″ [2]
Apparent magnitude  (V)	6.42 [1]
Characteristics
Evolutionary stage	main sequence [3]
Spectral type	O9.2IV [4]
Astrometry
Radial velocity (Rv)	+24.1 [5] km/s
Proper motion (μ)	RA: +9.659 [2] mas/yr Dec.: +13.159 [2] mas/yr
Parallax (π)	0.8968±0.0739  mas [2]
Distance	3,600 ± 300  ly (1,120 ± 90  pc)
Absolute magnitude  (MV)	−4.4 [3]
Details
Mass	17+19 −9 [6]   M☉
Radius	7.0+2.4 −1.8 [6]   R☉
Luminosity	79,433 [3]   L☉
Surface gravity (log g)	3.93 [3]   cgs
Temperature	33,500 [3]   K
Rotation	~63.5 days [3]
Rotational velocity (v sin i)	10 [3]  km/s
Age	4.5 [3]   Myr
Other designations
MCW 529, HD 57682, HIP 35707, HR 2806, SAO 134580, TIC 187458882, TYC 5395-4693-1, IRAS 07196-0852, 2MASS J07220205-0858457 [7]
Database references
SIMBAD	data

HD 57682 is a rare magnetic massive O-type main-sequence star star located in the constellation of Monoceros. It is one of only a small number of confirmed magnetic O-type stars and is notable for its strong dipolar magnetic field, which confines its stellar wind and produces observable spectroscopic variability. ^{[8] [9] [10]}

Discovery and Observation

The magnetic field was first reported in 2009, making HD 57682 one of the few known magnetic O-type stars at the time (fewer than 10 confirmed). Follow-up studies in 2012) refined the rotational period, magnetic geometry, and magnetospheric properties. The star's sharp spectral lines and low rotation make it an ideal target for studying magnetism in massive stars. ^{[6] [11]}

HD 57682 hosts a strong, organized dipolar magnetic field, discovered in 2009 as part of the Magnetism in Massive Stars (MiMeS) survey using spectropolarimetric observations with the ESPaDOnS instrument at the Canada-France-Hawaii Telescope. The surface polar strength of the dipole is estimated at approximately 880–1,680 G, with later refinements favoring lower values around 880 G and a high obliquity angle (~79°). It exhibits a weak stellar wind with a mass-loss rate of ~1.4×10⁻⁹  M_☉ /yr. The star is a runaway star, moving at high velocity away from its likely birthplace in the Canis Major OB1 association. ^{[6] [12] [13]}

References

1. 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. XHIP record for this object at VizieR.
2. Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv: 2208.00211 . Bibcode:2023A&A...674A...1G. doi: 10.1051/0004-6361/202243940 . S2CID   244398875. Gaia DR3 record for this source at VizieR.
3. Aschenbrenner, P.; Przybilla, N.; Butler, K. (2023). "Quantitative spectroscopy of late O-type main-sequence stars with a hybrid non-LTE method". Astronomy and Astrophysics. 671: A36. arXiv: 2301.09462 . Bibcode:2023A&A...671A..36A. doi:10.1051/0004-6361/202244906.
4. Sota, A.; Maíz Apellániz, J.; Morrell, N. I.; Barbá, R. H.; Walborn, N. R.; Gamen, R. C.; Arias, J. I.; Alfaro, E. J. (2014). "The Galactic O-Star Spectroscopic Survey (GOSSS). II. Bright Southern Stars". The Astrophysical Journal Supplement Series. 211 (1): 10. arXiv: 1312.6222 . Bibcode:2014ApJS..211...10S. doi:10.1088/0067-0049/211/1/10.
5. 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.
6. Grunhut, J. H.; Wade, G. A.; Marcolino, W. L. F.; Petit, V.; Henrichs, H. F.; Cohen, D. H.; Alecian, E.; Bohlender, D.; Bouret, J.-C.; Kochukhov, O.; Neiner, C.; St-Louis, N.; Townsend, R. H. D. (November 2009). "Discovery of a magnetic field in the O9 sub-giant star HD 57682 by the MiMeS Collaboration". Monthly Notices of the Royal Astronomical Society. 400 (1): L94 –L98. arXiv: 0910.0214 . Bibcode:2009MNRAS.400L..94G. doi: 10.1111/j.1745-3933.2009.00771.x .
7. "HD 57682". SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved 2025-12-17.
8. Martins, F.; Escolano, C.; Wade, G. A.; Donati, J. F.; Bouret, J. C.; Collaboration, MiMeS (2012-02-01). "Observational effects of magnetism in O stars: surface nitrogen abundances". Astronomy & Astrophysics. 538: A29. arXiv: 1112.2497 . Bibcode:2012A&A...538A..29M. doi:10.1051/0004-6361/201118039.
9. Rustem, Abdurepqet; Lü, Guo-Liang; Liu, Jin-Zhong; Zhu, Chun-Hua; Zhang, Yu; Shen, Dong-Xiang; Zhang, Yu-Hao; He, Xiao-Long (2023). "A Catalog and Statistical Analysis for Magnetic Stars". Research in Astronomy and Astrophysics. 23 (9). arXiv: 2307.12315 . Bibcode:2023RAA....23i5024R. doi:10.1088/1674-4527/ace9b0.
10. Grunhut, J. H.; Wade, G. A.; Neiner, C.; Oksala, M. E.; Petit, V.; Alecian, E.; Bohlender, D. A.; Bouret, J.-C.; Henrichs, H. F.; Hussain, G. A. J.; Kochukhov, O.; the MiMeS Collaboration (2017-02-21). "The MiMeS survey of Magnetism in Massive Stars: magnetic analysis of the O-type stars". Monthly Notices of the Royal Astronomical Society. 465 (2): 2432–2470. arXiv: 1206.5163 . Bibcode:2012ASPC..464..405W. doi: 10.1093/mnras/stw2743 .
11. Grunhut, J. H.; Wade, G. A.; Sundqvist, J. O.; ud-Doula, A.; Neiner, C.; Ignace, R.; Marcolino, W. L. F.; Rivinius, Th.; Fullerton, A.; Kaper, L.; Mauclaire, B.; Buil, C.; Garrel, T.; Ribeiro, J.; Ubaud, S. (2012-11-01). "Investigating the spectroscopic, magnetic and circumstellar variability of the O9 subgiant star HD 57682". Monthly Notices of the Royal Astronomical Society. 426 (3): 2208–2227. arXiv: 1207.6988 . Bibcode:2012MNRAS.426.2208G. doi: 10.1111/j.1365-2966.2012.21799.x .
12. Wade, G. A.; Grunhut, J.; Alecian, E.; Neiner, C.; Aurière, M.; Bohlender, D. A.; David-Uraz, A.; Folsom, C.; Henrichs, H. F.; Kochukhov, O.; Mathis, S.; Owocki, S.; Petit, V.; Petit (2014). "The magnetic characteristics of Galactic OB stars from the MiMeS survey of magnetism in massive stars". Magnetic Fields Throughout Stellar Evolution. 302: 265. arXiv: 1310.3965 . Bibcode:2014IAUS..302..265W. doi:10.1017/S1743921314002233.
13. Grunhut, Jason H.; Wade, Gregg A.; Marcolino, Wagner L. F.; Petit, Véronique; Petit (2011). A MiMeS analysis of the magnetic field and circumstellar environment of the weak-wind O9 sub-giant star HD 57682. Active OB stars: structure, evolution, mass loss, and critical limits, Proceedings of the International Astronomical Union, IAU Symposium. Vol. 272. p. 188. arXiv: 1009.3263 . Bibcode:2011IAUS..272..188G. doi:10.1017/S1743921311010271.