21 Aquilae is the Flamsteed designation for a star in the equatorial constellation of Aquila. Its apparent magnitude is 5.14 and it is located at a distance of around 710 [2 ] light-years (220 parsecs) from Earth, give or take a 40 light-year margin of error. The [1 ] stellar classification of this star is B8 II-III, with the [3 ] luminosity class of II-III suggesting that the spectrum displays elements of both a giant star and a bright giant. The outer atmosphere has an effective temperature of 13,175 K; this searing heat gives it the blue-white glow of a [3 ] B-type star. [7 ]
References [ edit ]
^ a b c d e f van Leeuwen, F. (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics 474 (2): 653–664, arXiv: 0708.1752, Bibcode: 2007A&A...474..653V, doi: 10.1051/0004-6361:20078357.
^ a b c d Stepien, K. (December 1968), "Photometric behavior of magnetic stars", Astrophysical Journal 154: 945, Bibcode: 1968ApJ...154..945S, doi: 10.1086/149815.
^ a b c d e f Cenarro, A. J. et al. (January 2007), "Medium-resolution Isaac Newton Telescope library of empirical spectra - II. The stellar atmospheric parameters", Monthly Notices of the Royal Astronomical Society 374 (2): 664–690, arXiv: astro-ph/0611618, Bibcode: 2007MNRAS.374..664C, doi: 10.1111/j.1365-2966.2006.11196.x.
^ Evans, D. S. (June 20–24, 1966), "The Revision of the General Catalogue of Radial Velocities", in Batten, Alan Henry; Heard, John Frederick, Determination of Radial Velocities and their Applications, Proceedings from IAU Symposium no. 30, University of Toronto: International Astronomical Union, Bibcode: 1967IAUS...30...57E.
^ Pasinetti Fracassini, L. E. et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics", Astronomy and Astrophysics 367 (2): 521–524, arXiv: astro-ph/0012289, Bibcode: 2001A&A...367..521P, doi: 10.1051/0004-6361:20000451.
^ "V1288 Aql -- Variable Star of alpha2 CVn type", SIMBAD Astronomical Database (Centre de Données astronomiques de Strasbourg) , retrieved . 2012-07-26
^ "The Colour of Stars", Australia Telescope, Outreach and Education (Commonwealth Scientific and Industrial Research Organisation), December 21, 2004 , retrieved 2012-01-16
External linkls [ edit ]