18 Boötis

Star in the constellation Boötes J2000 Boötes 14 19 16.27966 +13 00 15.4859 5.41 F3 V 0.385 0.011 −0.40 0.7 +105.273 −31.389 38.1262 0.1323 3.33 1.31 1.4 3.90 6731 229 commas −0.03 0.04 4.30 40.5 2.0 1.154 18 Boo +13°2782 1372 3841 125451 69989 5365 100975 J14193+1300 18+Boo 18 Boötis is a single star in the northern constellation of Boötes, located about 85 light years away from the Sun. It is visible to the naked eye as a faint, yellow-white hued star with an apparent visual magnitude of 5.41. This object is a suspected member of the Ursa Major Moving Group, based on velocity criteria. It has a magnitude 10.84 optical companion at an angular separation of 163.7 arcsecond along a position angle of 219°, as of 2010. This is an F-type main-sequence star with a stellar classification of F3 V. Older surveys gave a class of F5 IV, showing the luminosity class of a subgiant star. It shows strong evidence for short-term chromospheric variability, although it is not optically variable. 18 Boötis is an estimated 1.15 billion years old and is spinning with a projected rotational velocity of 40.5 km/s. It has 1.3 times the mass of the Sun and 1.4 times the Sun's radius. The star is radiating 3.9 times the luminosity of the Sun from its photosphere at an effective temperature of 6,731 K. An infrared excess has been detected that suggests a cold debris disk is orbiting 34.9 AU from the host star with a blackbody temperature fit of 65 K. References 1226844321337777536 18 Boo May 8, 2019 XHIP: An extended hipparcos compilation Anderson E. Francis Ch. Astronomy Letters . 38 5 331 2012 2012AstL...38..331A 1108.4971 10.1134/S1063773712050015 119257644 David Trevor J. Hillenbrand Lynne A. The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets The Astrophysical Journal 804 2 146 2015 2015ApJ...804..146D 10.1088/0004-637X/804/2/146 1501.03154 33401607 . Ammler-von Eiff Matthias Reiners Ansgar New measurements of rotation and differential rotation in A-F stars: are there two populations of differentially rotating stars? Astronomy & Astrophysics 1204.2459 542 A116 June 2012 . 10.1051/0004-6361/201118724 2012A&A...542A.116A 53666672 Nakajima Tadashi Morino Jun-Ichi Potential Members of Stellar Kinematic Groups within 30 pc of the Sun The Astronomical Journal 143 1 2 2012 . 2012AJ....143....2N 10.1088/0004-6256/143/1/2 free 1 Gáspár András Rieke George H. Ballering Nicholas The Correlation between Metallicity and Debris Disk Mass The Astrophysical Journal 826 2 171 2016 2016ApJ...826..171G . 1604.07403 10.3847/0004-637x/826/2/171 119241004 free Eggleton P. P. Tokovinin A. A. A catalogue of multiplicity among bright stellar systems Monthly Notices of the Royal Astronomical Society 389 2 869–879 September 2008 10.1111/j.1365-2966.2008.13596.x free . 2008MNRAS.389..869E 0806.2878 14878976 Gray R. O. Corbally C. J. Garrison R. F. McFadden M. T. Bubar E. J. McGahee C. E. O'Donoghue A. A. Knox E. R. Contributions to the Nearby Stars (NStars) Project: spectroscopy of stars earlier than M0 within 40 pc-The Southern Sample 1 The Astronomical Journal 132 1 161–170 July 2006 10.1086/504637 2006AJ....132..161G astro-ph/0603770 119476992 . Chromospheric Variability in Early F-Type Stars Rachford Brian L. Foight Dillon R. The Astrophysical Journal 698 1 786–802 June 2009 10.1088/0004-637X/698/1/786 2009ApJ...698..786R 0904.1620 693296 . A Comprehensive Census of Nearby Infrared Excess Stars Cotten Tara H. Song Inseok The Astrophysical Journal Supplement Series 225 1 15 24 July 2016 10.3847/0067-0049/225/1/15 . 2016ApJS..225...15C 1606.01134 118438871 free Eggen O. J. Space-velocity vectors for 3483 stars with proper motion and radial velocity Royal Observatory Bulletin 51 1962 79 1962RGOB...51...79E . . 1 Mason B. D. Wycoff G. L. Hartkopf W. I. Douglass G. G. Worley C. E. The Washington Visual Double Star Catalog The Astronomical Journal 2014 122 6 3466 2001AJ....122.3466M http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=B/wds 2015-07-22 10.1086/323920 free Category:F3V stars Category:Circumstellar disks Category:Ursa Major moving group Category:Boötes Category:Durchmusterung objects Bootis, 18 125451 069989 5365