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Double star in the constellation of Andromeda
HD 221776 is a double star in the northern constellation of Andromeda . With an apparent visual magnitude of 6.18,[ 2] spectral classification K5III, meaning that it is an orange giant star that has evolved off the main sequence . An infrared excess has been detected around this star, indicating the star is associated with a cloud of dust particles.[ 5]
There is a magnitude 11.8 companion at angular separation of 19.8″ along a position angle of 329°, as of 2002;[ 6] [ 7]
^ a b c d e 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 .^ a b c d e Jasniewicz, G.; et al. (February 1999), "Late-type giants with infrared excess. I. Lithium abundances", Astronomy and Astrophysics , 342 : 831–838, Bibcode :1999A&A...342..831J ^ Guetter, H. H.; Hewitt, A. V. (June 1984), "Photoelectric UBV photometry for 317 PZT and VZT stars", Publications of the Astronomical Society of the Pacific , 96 : 441–443, Bibcode :1984PASP...96..441G , doi :10.1086/131362 ^ Famaey, B.; et al. (2005). "Local kinematics of K and M giants from CORAVEL/Hipparcos/Tycho-2 data. Revisiting the concept of superclusters". Astronomy and Astrophysics . 430 : 165–186. arXiv :astro-ph/0409579 Bibcode :2005A&A...430..165F . doi :10.1051/0004-6361:20041272 . S2CID 17804304 . ^ a b c d Kim, Sungsoo S.; et al. (April 2001), "Extent of Excess Far-Infrared Emission around Luminosity Class III Stars", The Astrophysical Journal , 550 (2): 1000–1006, arXiv :astro-ph/0012001 Bibcode :2001ApJ...550.1000K , doi :10.1086/319803 , S2CID 118903790 ^ Mason, B. D.; et al. (2014), "The Washington Visual Double Star Catalog" , The Astronomical Journal , 122 (6): 3466–3471, Bibcode :2001AJ....122.3466M , doi :10.1086/323920 , retrieved 2015-07-22 ^ 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 .
