1 Centauri

Yellow-white-hued star in the constellation Centaurus i Centauri HD 102776j Centauri HD 110073l Centauri Iota Centauriι Centauri Centaurus constellation map.svg center 280 right Red circle.svg 10 1 Centauri 455 238 Location of 1 Centauri (circled in red) J2000.0 Centaurus 13 45 41.24482 −33 02 37.3997 +4.23 main sequence F2 V +0.38 +0.00 −21.5 0.6 −462.49 0.18 −146.49 0.16 51.54 0.19 +2.81 9.94480 0.00441 none d 0.247 0.105 2,422,737.382 ± 3.35 JD 137.7 25.4 6.00 0.75 1.35 1.86 5.857 6898 235 commas −0.09 86 2.42 0.22 4.25 0.14 1.193 i Centauri 1 Centauri −32°9603 506 525.1 119756 67153 5168 204812 18593 1 Cen 2018-02-09 1+Cen 1 Centauri, or i Centauri, is a yellowhite-hued binary star system in the southern constellation Centaurus. It can be seen with the naked eye, having an apparent visual magnitude of +4.23. Based upon an annual parallax shift of 51.54 mas as seen from Earth's orbit, it is located 63.3 light-years from the Sun. The system is moving closer to the Sun with a radial velocity of −21.5 km/s. Spectrographic images taken at the Cape Observatory between 1921 and 1923 showed this star has a variable radial velocity, which indicated this is a single-lined spectroscopic binary star system. The pair have an orbital period of 9.94 days and an eccentricity of about 0.2. The primary component has received a number of different stellar classifications. For example, Jaschek et al. (1964) lists F0V, F2III, F4III and F4IV, thus ranging in evolutionary state from an ordinary F-type main-sequence star to a giant star. More recently, Houk (1982) listed a class of F3 V, matching an ordinary main-sequence star that is generating energy through hydrogen fusion at its core. The NStars project gives it a classification of F2 V. References Hardegree-Ullman Kevin K. Apai Dániel Bergsten Galen J. Pascucci Ilaria López-Morales Mercedes Bioverse: A Comprehensive Assessment of the Capabilities of Extremely Large Telescopes to Probe Earth-like O2 Levels in Nearby Transiting Habitable-zone Exoplanets The Astronomical Journal 2023 165 6 267 10.3847/1538-3881/acd1ec free 2304.12490 2023AJ....165..267H 1 Pizzolato N. Maggio A. Sciortino S. Evolution of X-ray activity of 1-3 Msun late-type stars in early post-main-sequence phases Astronomy and Astrophysics 361 614–628 September 2000 2000A&A...361..614P XHIP: An extended hipparcos compilation Anderson E. Francis Ch. Astronomy Letters 38 5 331 2012 2012AstL...38..331A 10.1134/S1063773712050015 1108.4971 119257644 . de Bruijne J. H. J. Eilers A.-C. Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project Astronomy & Astrophysics 546 A61 14 October 2012 10.1051/0004-6361/201219219 2012A&A...546A..61D 1208.3048 59451347 . 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 . Michigan Catalogue of Two-dimensional Spectral Types for the HD Stars Michigan Catalogue of Two-dimensional Spectral Types for the HD Stars. Volume_3. Declinations -40_ƒ0 to -26_ƒ0 3 Houk Nancy Ann Arbor, Michigan . Dept. of Astronomy, University of Michigan 1979 1982mcts.book.....H Radial velocity determinations : including a spectroscopic determination of the constant of aberration, the orbits of 13 spectroscopic binary stars, and the radial velocities of 434 stars Spencer Jones Harold Annals of the Cape Observatory 10 1928 246 1928AnCap..10....8S . Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 pc--The Southern Sample 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. The Astronomical Journal 132 161–170 2006 1 10.1086/504637 2006AJ....132..161G astro-ph/0603770 119476992 . Incidence of debris discs around FGK stars in the solar neighbourhood 1 Montesinos B. Eiroa C. Krivov A. V. Marshall J. P. Pilbratt G. L. Liseau R. Mora A. Maldonado J. Wolf S. Ertel S. Bayo A. Augereau J.-C. Heras A. M. Fridlund M. Danchi W. C. Solano E. Kirchschlager F. del Burgo C. Montes D. Astronomy & Astrophysics . 593 A51 31 September 2016 10.1051/0004-6361/201628329 2016A&A...593A..51M 1605.05837 55251562 Correlation of spectroscopic and photometric data Hauck B. International Astronomical Union, Colloquium on Spectral Classification of the Future, Vatican City, July 11–15, 1978. Ricerche Astronomiche (IAU Colloquium 47) 9 1979 161–178 1979RA......9..161H . Validation of the new Hipparcos reduction van Leeuwen F. Astronomy and Astrophysics 474 2 653–664 2007 0708.1752 2007A&A...474..653V 10.1051/0004-6361:20078357 free 18759600 Vizier catalog entry 1991bsc..book.....H The Bright star catalogue New Haven Hoffleit Dorrit Jaschek Carlos 1991 Category:Spectroscopic binaries Category:Centaurus Centauri, i CD-32 09603 Centauri, 1 00525.1 119756 067153 5168 Category:F2V stars