HD 195564
Star in the constellation Capricornus
HD 195564 is the Henry Draper Catalogue designation for a star in the southern constellation of Capricornus . It is faintly visible to the naked eye with an apparent visual magnitude of 5.65.[ 2] Parallax measurements give us an estimate of its distance as 81 light years . This is a candidate wide binary system as a faint companion star shares a common proper motion with the brighter primary component.[ 7]
Based upon the spectrum of light emitted by the primary, it has a stellar classification of G2 V.[ 3] This indicates that it is a G-type main sequence star that is generating energy through the process of thermonuclear fusion in its core region. It has an estimated mass of 1.097[ 5] times the mass of the Sun, but a measured radius that is 1.867 times as large.[ 5] As a result, it shines with 2.705 times the luminosity of the Sun.[ 5] The abundance of elements in this star is similar to that in the Sun, although it is an older star with an age of around 8.2 billion years.[ 5] The effective temperature of the stellar atmosphere is 5,421 K,[ 5] giving it the yellow-hued glow of an ordinary K-type star .[ 9]
The secondary companion has an apparent magnitude of 11.30,[ 10] and a mass just 55% that of the Sun.[ 7] As measured in 1965, it had an angular separation of 3.20″ from the primary, along a position angle of 27°[ 10] The pair orbit each other with an estimated period of around 510 years.[ 7]
In a paper published in April 2017, a candidate planet was found orbiting HD 195564 with a period of 5,404 days (14.80 yr).[ 11]
References
^ a b c d Brown, A. G. A. ; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties" . Astronomy & Astrophysics . 649 : A1. arXiv :2012.01533 . Bibcode :2021A&A...649A...1G . doi :10.1051/0004-6361/202039657 . S2CID 227254300 . (Erratum: doi :10.1051/0004-6361/202039657e ) . Gaia EDR3 record for this source at VizieR .
^ a b c d Mermilliod, J.-C. (1986), "Compilation of Eggen's UBV data, transformed to UBV (unpublished)", Catalogue of Eggen's UBV Data , SIMBAD , Bibcode :1986EgUBV........0M .
^ a b c Gray, R. O.; et al. (2003), "Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 Parsecs: The Northern Sample. I", The Astronomical Journal , 126 (4): 2048– 2059, arXiv :astro-ph/0308182 , Bibcode :2003AJ....126.2048G , doi :10.1086/378365 , S2CID 119417105 .
^ Nidever, David L.; et al. (August 2002), "Radial Velocities for 889 Late-Type Stars", The Astrophysical Journal Supplement Series , 141 (2): 503– 522, arXiv :astro-ph/0112477 , Bibcode :2002ApJS..141..503N , doi :10.1086/340570 , S2CID 51814894 .
^ a b c d e f g h i j k Boyajian, Tabetha S.; et al. (July 2013), "Stellar Diameters and Temperatures. III. Main-sequence A, F, G, and K Stars: Additional High-precision Measurements and Empirical Relations", The Astrophysical Journal , 771 (1): 31, arXiv :1306.2974 , Bibcode :2013ApJ...771...40B , doi :10.1088/0004-637X/771/1/40 , S2CID 14911430 , 40. See Table 3.
^ Martínez-Arnáiz, R.; et al. (September 2010), "Chromospheric activity and rotation of FGK stars in the solar vicinity. An estimation of the radial velocity jitter" (PDF) , Astronomy and Astrophysics , 520 : A79, arXiv :1002.4391 , Bibcode :2010A&A...520A..79M , doi :10.1051/0004-6361/200913725 , S2CID 43455849 , archived from the original (PDF) on 2017-09-22, retrieved 2018-11-04 .
^ a b c d Tokovinin, Andrei (April 2014), "From Binaries to Multiples. II. Hierarchical Multiplicity of F and G Dwarfs", The Astronomical Journal , 147 (4): 14, arXiv :1401.6827 , Bibcode :2014AJ....147...87T , doi :10.1088/0004-6256/147/4/87 , S2CID 56066740 , 87.
^ "HD 195564" . SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved March 15, 2016 .
^ "The Colour of Stars" , Australia Telescope, Outreach and Education , Commonwealth Scientific and Industrial Research Organisation , December 21, 2004, archived from the original on March 18, 2012, retrieved 2012-01-16 .
^ a b 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 .
^ a b Butler, R. Paul; et al. (13 April 2017). "The LCES HIRES/Keck Precision Radial Velocity Exoplanet Survey" . The Astronomical Journal . 153 (5): 208. arXiv :1702.03571 . Bibcode :2017AJ....153..208B . doi :10.3847/1538-3881/aa66ca . hdl :2299/18220 . S2CID 14954371 . Planet candidate is in Table 2; full table available here .