Beta Doradus, Latinized from β Doradus, is the second brightest star in the southern constellation of Dorado.[11] It has a variable apparent visual magnitude,[4] and is visible to the naked eye from the southern hemisphere. Based upon parallax measurements with the Hubble Space Telescope, it is located at a distance of 1,040 light-years (320 parsecs) from Earth.[12]
Beta Doradus is a Cepheid variable that regularly changes magnitude from a low of 4.08 to a high of 3.46[2] over a period of 9.84318days.[14] The light curve of this magnitude change follows a nearly regular saw-tooth pattern, with average amplitude variations period to period about 0.005 magnitude from average amplitude of 0.62 magnitude.[14] During each radial pulsation cycle, the radius of the star varies by ±3.9 times the Sun's radius around a mean of 67.8.[8] Its spectral type and luminosity class are likewise variable, from F-type to G-type and from a supergiant to a bright giant.[3]
Far ultraviolet emissions have been detected from this star with the Far Ultraviolet Spectroscopic Explorer, while X-ray emissions were detected with the XMM-Newton space telescope. The X-ray luminosity is about 1 × 1029 erg/s and the emission varies with the pulsation period, suggesting a connection with the pulsation process. The peak X-ray emissions are in the 0.6–0.8keV energy range, which occurs for plasmas with temperatures of 7–10 million K.[15]
HR 1922, database entry, The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version), D. Hoffleit and W. H. Warren, Jr., CDS ID V/50. Accessed on line September 9, 2008.
Turner, D. G. (April 1980), "The reddening of Beta Doradus", Journal of the Royal Astronomical Society of Canada, 74: 64–69, Bibcode:1980JRASC..74...64T
Evans, D. S. (June 20–24, 1966), Batten, Alan Henry; Heard, John Frederick (eds.), "The Revision of the General Catalogue of Radial Velocities", Determination of Radial Velocities and their Applications, Proceedings from IAU Symposium no. 30, University of Toronto: International Astronomical Union, Bibcode:1967IAUS...30...57E
Turner, David G. (April 2010), "The PL calibration for Milky Way Cepheids and its implications for the distance scale", Astrophysics and Space Science, 326 (2): 219–231, arXiv:0912.4864, Bibcode:2010Ap&SS.326..219T, doi:10.1007/s10509-009-0258-5, S2CID119264970
Romaniello, M.; etal. (September 2008), "The influence of chemical composition on the properties of Cepheid stars. II. The iron content", Astronomy and Astrophysics, 488 (2): 731–747, arXiv:0807.1196, Bibcode:2008A&A...488..731R, doi:10.1051/0004-6361:20065661, S2CID16955805
"V* bet Dor". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved September 9, 2008.
Kaler, James B., "Beta Doradus", Stars, University of Illinois, retrieved 2012-01-01
McArthur, Barbara E.; etal. (May 2011), "Astrometry with the Hubble Space Telescope: Trigonometric Parallaxes of Selected Hyads", The Astronomical Journal, 141 (5): 172, arXiv:1103.2094, Bibcode:2011AJ....141..172M, doi:10.1088/0004-6256/141/5/172, S2CID119206374
Plachy, E.; etal. (2021), "TESS Observations of Cepheid Stars: First Light Results", The Astrophysical Journal Supplement Series, 253: 11, arXiv:2012.09709, doi:10.3847/1538-4365/abd4e3, S2CID229297708
Engle, Scott G.; etal. (May 2009), "The Secret XUV Lives of Cepheids: FUV/X-ray observations of Polaris and β Dor", Future Directions in Ultraviolet Spectroscopy: A Conference Inspired by the Accomplishments of the Far Ultraviolet Spectroscopic Explorer Mission, AIP Conference Proceedings, vol.1135, pp.192–197, arXiv:0902.3449, Bibcode:2009AIPC.1135..192E, doi:10.1063/1.3154048, S2CID16635363
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