HD_37017
HD 37017
Binary star system in the constellation Orion
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]
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]