Binary star system in the constellation Ophiuchus
72 Ophiuchi Location of 72 Ophiuchi (circled)
Observation dataEpoch J2000 Equinox J2000 Constellation Ophiuchus Right ascension 18h 07m 20.98393s [ 1] Declination 9° 33′ 49.8501″[ 1] Apparent magnitude (V)3.73[ 2] [ 3] Characteristics Spectral type A5 V[ 4] U−Bcolor index +0.10[ 2] B−Vcolor index +0.12[ 2] Astrometry Radial velocity (Rv )-23.90[ 5] km/s Proper motion (μ)RA: -62.17[ 1] mas /yr Dec.: +79.66[ 1] mas /yr Parallax (π)37.55± 0.21 mas [ 1] Distance 86.9 ± 0.5 ly pc ) Absolute magnitude (MV )1.58[ 6] Details Mass 1.99[ 7] M ☉ Radius 1.9[ 8] R ☉ Luminosity 20[ 7] L ☉ Surface gravity (log g )4.04[ 9] cgs Temperature 8,718[ 9] K Metallicity +0.09[ 6] dex Rotational velocity (v sin i )65[ 7] Age 250[ 9] Myr Other designations 72 Oph ,BD +09°3564FK5 680GC 24695GJ 9615 AHD 165777HIP 88771HR 6771SAO 123142CCDM J18073+0934AWDS J18073+0934A[ 10] Database references SIMBAD data
72 Ophiuchi is abinary star [ 3] equatorial constellation ofOphiuchus . It is visible to the naked eye as a faint, white-hued point of light with a combinedapparent visual magnitude of 3.73.[ 2] light years away from the Sun based onparallax ,[ 1] radial velocity of -23.9 km/s.[ 5]
As of 2008, the pair had anangular separation of″ [ 3] stellar classification of A5 V,[ 4] A-type main-sequence star . Cowley et al. (1969) had assigned it to a class of A4 IVs,[ 11] lined (s)subgiant star . The latter class is still in use by some sources.[ 7] [ 3] [ 12]
The primary is 250[ 9] [ 7] mass of the Sun and is spinning with a moderateprojected rotational velocity of 65 km/s.[ 7] [ 7] luminosity of the Sun from itsphotosphere at aneffective temperature of 8,718 K.[ 9] infrared excess , suggesting adebris disk is orbiting the star with a mean separation ofAU [ 13] X-ray emission ,[ 12] [ 3] [ 12]
There are additionalvisual companions : component C with magnitude 11.5 lies at anangular separation of″ [ 14] [ 15]
This star was once considered part of the obsolete constellationTaurus Poniatovii , the brightest star in it. After theInternational Astronomical Union officially recognised constellations, it was placed in Ophiuchus.[ 16]
^a b c d e f Van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction".Astronomy and Astrophysics .474 (2):653– 664.arXiv :0708.1752 Bibcode :2007A&A...474..653V .doi :10.1051/0004-6361:20078357 .S2CID 18759600 . Vizier catalog entry ^a b c d Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system".CDS/ADC Collection of Electronic Catalogues .2237 .Bibcode :2002yCat.2237....0D . ^a b c d e Eggleton, P. P.; Tokovinin, A. A. (September 2008)."A catalogue of multiplicity among bright stellar systems" .Monthly Notices of the Royal Astronomical Society 389 (2):869– 879.arXiv :0806.2878 Bibcode :2008MNRAS.389..869E .doi :10.1111/j.1365-2966.2008.13596.x S2CID 14878976 . ^a b 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.arXiv :astro-ph/0308182 Bibcode :2003AJ....126.2048G .doi :10.1086/378365 .S2CID 119417105 . ^a b Kharchenko, N. V.; Scholz, R.-D.; Piskunov, A. E.; Röser, S.; Schilbach, E. (2007). "Astrophysical supplements to the ASCC-2.5: Ia. Radial velocities of ~55000 stars and mean radial velocities of 516 Galactic open clusters and associations".Astronomische Nachrichten .328 (9): 889.arXiv :0705.0878 Bibcode :2007AN....328..889K .doi :10.1002/asna.200710776 .S2CID 119323941 . ^a b 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 . Vizier catalog entry ^a b c d e f g Zorec, J.; Royer, F. (2012). "Rotational velocities of A-type stars".Astronomy & Astrophysics .537 : A120.arXiv :1201.2052 Bibcode :2012A&A...537A.120Z .doi :10.1051/0004-6361/201117691 .S2CID 55586789 . Vizier catalog entry ^ Allende Prieto, C.; Lambert, D. L. (1999). "Fundamental parameters of nearby stars from the comparison with evolutionary calculations: Masses, radii and effective temperatures".Astronomy and Astrophysics .352 :555– 562.arXiv :astro-ph/9911002 Bibcode :1999A&A...352..555A . Vizier catalog entry ^a b c d e David, Trevor J.; Hillenbrand, Lynne A. (2015). "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.arXiv :1501.03154 Bibcode :2015ApJ...804..146D .doi :10.1088/0004-637X/804/2/146 .S2CID 33401607 . Vizier catalog entry ^ "72 Oph" .SIMBAD Centre de données astronomiques de Strasbourg . Retrieved2019-06-26 .^ Cowley, A.; et al. (April 1969). "A study of the bright A stars. I. A catalogue of spectral classifications".Astronomical Journal .74 :375– 406.Bibcode :1969AJ.....74..375C .doi :10.1086/110819 . ^a b c De Rosa, R. J.; et al. (July 2011)."The Volume-limited A-Star (VAST) survey - I. Companions and the unexpected X-ray detection of B6-A7 stars" .Monthly Notices of the Royal Astronomical Society .415 (1):854– 866.arXiv :1103.4363 Bibcode :2011MNRAS.415..854D .doi :10.1111/j.1365-2966.2011.18765.x S2CID 84181878 . ^ Gáspár, András; et al. (2016)."The Correlation between Metallicity and Debris Disk Mass" .The Astrophysical Journal .826 (2): 171.arXiv :1604.07403 Bibcode :2016ApJ...826..171G .doi :10.3847/0004-637X/826/2/171 S2CID 119241004 . ^ Renson, P.; Manfroid, J. (2009)."Catalogue of Ap, HgMn and Am stars" .Astronomy and Astrophysics .498 (3): 961.Bibcode :2009A&A...498..961R .doi :10.1051/0004-6361/200810788 ^ Mason, Brian D.; et al. (2001)."The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog" .The Astronomical Journal .122 (6): 3466.Bibcode :2001AJ....122.3466M .doi :10.1086/323920 Vizier catalog entry ^ Ian Ridpath."Taurus Poniatovii" .Star Tales . Retrieved2023-11-01 .
