HD 34626

HD 34626, also known as MZ Aurigae, is an unusual variable star in the northern constellation of Auriga. It has an apparent magnitude of 8.2 and is about 3,300 light years away.

HD 34626

A light curve for HD 34626 from KELT data, adapted from Labadie-Bartz et al. (2017)[1]
Observation data
Epoch J2000      Equinox J2000
Constellation Auriga
Right ascension 05h 20m 33.03590s[2]
Declination +36° 37′ 56.0306″[2]
Apparent magnitude (V) 8.16[3]
Characteristics
Spectral type B1.5 IVnp[4]
U−B color index −0.68[5]
B−V color index +0.03[5]
Variable type SX Ari?[6]
Astrometry
Radial velocity (Rv)−6[7] km/s
Proper motion (μ) RA: −0.630[2] mas/yr
Dec.: −4.017[2] mas/yr
Parallax (π)0.9831 ± 0.0356 mas[2]
Distance3,300 ± 100 ly
(1,020 ± 40 pc)
Details
Mass4.4[2] M☉
Radius21[2] R☉
Luminosity556[2] L☉
Temperature22,675[3] K
Rotational velocity (v sin i)310[8] km/s
Age200[9] Myr
Other designations
MZ Aurigae, MZ Aur, BD+36°1090, HD 34626, HIP 24938, SAO 57915.
Database references
SIMBADdata

The spectrum of HD 34626 had long been known to be unusual, with very broad lines indicating rapid rotation and emission lines marking it as a Be star. In 1970, it was found to vary in brightness by 0.1 magnitude over time scales of 8 to 12 hours, but these variations are not periodic.[10] This indicates the variability is not caused by ellipsoidal effects, and the nature of the variability remains unknown.[8] It may be a type of SX Arietis variable.[6]

HD 34626 has exhausted its core hydrogen and evolved away from the main sequence. Its spectral type indicates that it is a subgiant, but evolutionary models suggest it may be in the giant stage.[2]

References
  1. Labadie-Bartz, Jonathan; Pepper, Joshua; McSwain, M. Virginia; Bjorkman, J. E.; Bjorkman, K. S.; Lund, Michael B.; Rodriguez, Joseph E.; Stassun, Keivan G.; Stevens, Daniel J.; James, David J.; Kuhn, Rudolf B.; Siverd, Robert J.; Beatty, Thomas G. (May 2017). "Photometric Variability of the Be Star Population". The Astronomical Journal. 153 (6): 252. arXiv:1609.08449. Bibcode:2017AJ....153..252L. doi:10.3847/1538-3881/aa6396. S2CID 119234382. Retrieved 30 October 2021.
  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. 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. Walborn, N. R. (1971). "Some Spectroscopic Characteristics of the OB Stars: An Investigation of the Space Distribution of Certain OB Stars and the Reference Frame of the Classification". The Astrophysical Journal Supplement Series. 23: 257. Bibcode:1971ApJS...23..257W. doi:10.1086/190239.
  5. Deutschman, W. A.; Davis, R. J.; Schild, R. E. (February 1976), "The galactic distribution of interstellar absorption as determined from the Celescope catalog of ultraviolet stellar observations and a new catalog of UBV, H-beta photoelectric observations", Astrophysical Journal Supplement Series, 30: 97–225, Bibcode:1976ApJS...30...97D, doi:10.1086/190359
  6. "MZ Aur". International Variable Star Index. AAVSO. Retrieved 2022-09-27.
  7. Gontcharov, G. A. (November 2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. S2CID 119231169.
  8. Percy, J. R. (December 1984), "Five suspected Beta Cephei stars revisited", Journal of the Royal Astronomical Society of Canada, 78: 241–250, Bibcode:1984JRASC..78..241P
  9. Tetzlaff, N.; Neuhäuser, R.; Hohle, M.M. (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. arXiv:1007.4883. Bibcode:2011MNRAS.410..190T. doi:10.1111/j.1365-2966.2010.17434.x. S2CID 118629873.
  10. Percy, J. R. (1970). "A photometric study of some early B stars whose spectral lines vary in sharpness". The Astronomical Journal. 75: 818. Bibcode:1970AJ.....75..818P. doi:10.1086/111026.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.