Star in the constellation Aquarius
17 Aquarii , abbreviated 17 Aqr , is a spectroscopic binary [ 5] star system in the constellation of Aquarius . 17 Aquarii is the Flamsteed designation . It appears to the naked eye as a faint sixth magnitude star, having a combined apparent visual magnitude of 5.99.[ 2] The distance to 17 Aqr can be estimated from its annual parallax shift of 4.9 mas ,[ 1] which yields a separation of around 660 light years . It is moving further away with a heliocentric radial velocity of 18 km/s.[ 4]
A preliminary orbit for the pair gives a period of 20 years and an eccentricity of 0.4.[ 5] The primary component is an aging giant star with a stellar classification of K4/5 III.[ 3] It is radiating 495[ 2] times the Sun's luminosity from its photosphere at an effective temperature of 3,951 K.[ 6]
References
^ a b c d e f 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 .
^ a b c d e f Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters , 38 (5): 331, arXiv :1108.4971 , Bibcode :2012AstL...38..331A , doi :10.1134/S1063773712050015 , S2CID 119257644 .
^ a b Houk, N.; Swift, C. (1999), "Michigan catalogue of two-dimensional spectral types for the HD Stars", Michigan Spectral Survey , 5 , Bibcode :1999MSS...C05....0H .
^ a b Gontcharov, G. A. (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 .
^ a b c Famaey, B.; et al. (2009). "Spectroscopic binaries among Hipparcos M giants,. I. Data, orbits, and intrinsic variations". Astronomy and Astrophysics . 498 (2): 627– 640. arXiv :0901.0934 . Bibcode :2009A&A...498..627F . doi :10.1051/0004-6361/200810698 . S2CID 18739721 .
^ a b c d Wu, Yue; et al. (2010). "Coudé-feed stellar spectral library – atmospheric parameters". Astronomy & Astrophysics . 525 : A71. arXiv :1009.1491 . Bibcode :2011A&A...525A..71W . doi :10.1051/0004-6361/201015014 . S2CID 53480665 .
^ "17 Aqr" . SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved October 22, 2018 .