HD 37017

HD 37017 is a binary star system in the equatorial constellation of Orion. It has the variable star designation V1046 Orionis; HD 37017 is the identifier from the Henry Draper Catalogue. The system is a challenge to view with the naked eye, being close to the lower limit of visibility with a combined apparent visual magnitude of 6.55.^[3] It is located at a distance of approximately 1,230 light years based on parallax,^[9] and is drifting further away with a radial velocity of +32 km/s.^[8] The system is part of star cluster NGC 1981.^[13]

HD 37017

A light curve for V1046 Orionis, plotted from TESS data[1]
Observation data Epoch J2000      Equinox J2000
Constellation	Orion
Right ascension	05h 35m 21.86770s[2]
Declination	−04° 29′ 39.0409″[2]
Apparent magnitude (V)	6.553[3]
Characteristics
Evolutionary stage	B2/3V[4] (B1.5 Vp He strong[5])
U−B color index	−0.79[6]
B−V color index	−0.14[6]
Variable type	SX Ari[7]
Astrometry
Radial velocity (Rv)	+32±2[8] km/s
Proper motion (μ)	RA: 1.88±0.09[9] mas/yr Dec.: 1.20±0.14[9] mas/yr
Parallax (π)	2.643 ± 0.075 mas[9]
Distance	1,230 ± 40 ly (380 ± 10 pc)
Orbit[10]
Period (P)	18.6556±0.0017 d
Semi-major axis (a)	≥12.61±1.09 R☉
Eccentricity (e)	0.31±0.05
Periastron epoch (T)	2,435,461.602±0.168 JD
Argument of periastron (ω) (secondary)	133±5°
Semi-amplitude (K1) (primary)	36.0±2.5 km/s
Details
A
Mass	8.50±0.53[3] M☉
Luminosity	3,754[3] L☉
Temperature	23,700[3] K
Rotation	0.901 d[11]
Rotational velocity (v sin i)	165[5] km/s
B
Mass	4.5[10] M☉
Other designations
V1046 Orionis, BD−04°1183, HD 37017, HIP 26233, HR 1890, SAO 132317[12]
Database references
SIMBAD	data

The binary nature of this system was suggested by A. Blaauw and T. S. van Albada in 1963.^[10] It is a double-lined^[11] spectroscopic binary with an orbital period of 18.6556 days and an eccentricity of 0.31.^[14] The eccentricity is considered unusually large for such a close system.^[11] It forms a suspected eclipsing binary that ranges in brightness from 6.54 down to 6.58.^[7]

The primary is a helium-strong, magnetic chemically peculiar star^[15] with a stellar classification of B1.5 Vp.^[5] It has a magnetic field strength of 7,700 G,^[16] and the helium concentrations are located at the magnetic poles.^[17] V1046 Orionis was found to be a variable star by L. A. Balona in 1997,^[11] and is now classified as an SX Arietis variable.^[7] The star undergoes periodic changes in visual brightness, magnetic field strength, and spectral characteristics with a cycle time of 0.901175 days – the star's presumed rotation period.^[11] Radio emission has been detected that varies with the rotation period.^[17]

The secondary component has an estimated 4.5 times the mass of the Sun. The class has been estimated as type B6III-IV.^[11]

References

1. "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. Retrieved 8 December 2021.
2. 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.
3. Hohle, M. M.; et al. (April 2010), "Masses and luminosities of O- and B-type stars and red supergiants", Astronomische Nachrichten, 331 (4): 349–360, arXiv:1003.2335, Bibcode:2010AN....331..349H, doi:10.1002/asna.200911355, S2CID 111387483.
4. Houk, N.; Swift, C. (1999). "Michigan catalogue of two-dimensional spectral types for the HD Stars". Michigan Spectral Survey. 5. Bibcode:1999MSS...C05....0H.
5. Abt, Helmut A.; et al. (July 2002), "Rotational Velocities of B Stars", The Astrophysical Journal, 573 (1): 359–365, Bibcode:2002ApJ...573..359A, doi:10.1086/340590.
6. Walker, M. F. (February 1969), "Studies of extremely young clusters. V. Stars in the vicinity of the Orion nebula", Astrophysical Journal, 155: 447, Bibcode:1969ApJ...155..447W, doi:10.1086/149881.
7. 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.
8. Blaauw, A.; et al. (April 1963), "Radial Velocities of B-Type Stars in the Nearest Associations.", Astrophysical Journal, 137: 791, Bibcode:1963ApJ...137..791B, doi:10.1086/147556.
9. Kounkel, Marina; et al. (2017), "The Gould's Belt Distances Survey (GOBELINS) II. Distances and Structure toward the Orion Molecular Clouds", The Astrophysical Journal, 834 (2), 142, arXiv:1609.04041, Bibcode:2017ApJ...834..142K, doi:10.3847/1538-4357/834/2/142, hdl:1887/59417, S2CID 26439367.
10. Leone, F.; Catanzaro, G. (March 1999), "Orbital elements of binary systems with a chemically peculiar star", Astronomy and Astrophysics, 343: 273–280, Bibcode:1999A&A...343..273L.
11. Bolton, C. T.; et al. (September 1998), "HD 37017 = V 1046 ORI A double-lined spectroscopic binary with a B2e He-strong magnetic primary", Astronomy and Astrophysics, 337: 183–197, Bibcode:1998A&A...337..183B.
12. "V1046 Ori". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-12-31.
13. Maia, F. F. S.; et al. (September 2010), "Characterization and photometric membership of the open cluster NGC1981", Monthly Notices of the Royal Astronomical Society, 407 (3): 1875–1886, arXiv:1005.3047, Bibcode:2010MNRAS.407.1875M, doi:10.1111/j.1365-2966.2010.17034.x, S2CID 119206669.
14. Ducati, J. R.; et al. (January 2011), "The mass ratio and initial mass functions in spectroscopic binaries" (PDF), Astronomy and Astrophysics, 525: 9, Bibcode:2011A&A...525A..26D, doi:10.1051/0004-6361/200913895, A26.
15. Ghazaryan, S.; et al. (August 2019), "Statistical analysis of roAp, He-weak, and He-rich stars", Monthly Notices of the Royal Astronomical Society, 487 (4): 5922–5931, arXiv:1906.06984, Bibcode:2019MNRAS.487.5922G, doi:10.1093/mnras/stz1678, S2CID 189928323.
16. Trigilio, C.; et al. (May 2004), "A three-dimensional model for the radio emission of magnetic chemically peculiar stars", Astronomy and Astrophysics, 418 (2): 593–605, arXiv:astro-ph/0402432, Bibcode:2004A&A...418..593T, doi:10.1051/0004-6361:20040060, S2CID 15884571.
17. Leone, F.; Umana, G. (January 1993), Dworetsky, M. M.; Castelli, F.; Faraggiana, R. (eds.), "Periodic Radio Emission from the Helium Rich Stars HD 37017 and σ Ori E", Peculiar versus Normal Phenomena in A-type and Related Stars. International Astronomical Union, Colloquium No. 138, held in Trieste, Italy, July 1992, vol. 44, no. 138, San Francisco: Astronomical Society of the Pacific, p. 541, Bibcode:1993ASPC...44..541L.

External links

• Simbad