68 Ophiuchi

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

68 Ophiuchi
Ophiuchus constellation map.svg
Red circle.svg
Location of 68 Ophiuchi (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Ophiuchus
Right ascension 18h 01m 45.19884s[1]
Declination 1° 18′ 18.2775″[1]
Apparent magnitude (V) 4.42[2]
Spectral type A2Vn[3]
U−B color index +0.02[4]
B−V color index +0.04[4]
Radial velocity (Rv)+6.00[5] km/s
Proper motion (μ) RA: +15.93[1] mas/yr
Dec.: -13.29[1] mas/yr
Parallax (π)11.15 ± 0.60[1] mas
Distance290 ± 20 ly
(90 ± 5 pc)
Absolute magnitude (MV)-0.34[2]
Period (P)175.74±4.65 yr
Semi-major axis (a)1.090±0.027
Eccentricity (e)0.831±0.035
Inclination (i)69.5±3.0°
Longitude of the node (Ω)160.2±1.6°
Periastron epoch (T)2019.87±1.48
Argument of periastron (ω)
Mass3.07[7] M
Radius4.5[8] R
Luminosity160[7] L
Surface gravity (log g)3.76[9] cgs
Temperature9,594[7] K
Metallicity [Fe/H]-0.14[10] dex
Rotational velocity (v sin i)201[7] km/s
Other designations
BD+01°3560, CCDM J18018+0118AB, GC 24534, HIP 88290, HR 6723, HD 164577, NSV 10009, SAO 123035, WDS J18018+0118AB
Database references

68 Ophiuchi is a star in the constellation Ophiuchus. Its apparent magnitude is 4.42.[2] Located around 89.69 parsecs (292.5 ly) distant,[1] it is a blue-white main-sequence star of spectral type A2Vn,[3] a star that is currently fusing its core hydrogen. The star is suspected of varying between magnitudes 4.42 and 4.48.[11]

It is a binary, with a companion, B, of magnitude 7.48, in an orbit with period 176 years and eccentricity 0.83.[12][13]


  1. ^ a b c d e f Van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. Vizier catalog entry
  2. ^ a b c 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. Vizier catalog entry
  3. ^ a b Hoffleit, D.; Warren, W. H. (1995). "VizieR Online Data Catalog: Bright Star Catalogue, 5th Revised Ed. (Hoffleit+, 1991)". VizieR On-line Data Catalog: V/50. Originally published in: 1964BS....C......0H. 5050. Bibcode:1995yCat.5050....0H.
  4. ^ a b Mallama, A. (2014). "Sloan Magnitudes for the Brightest Stars". The Journal of the American Association of Variable Star Observers. 42: 443. Bibcode:2014JAVSO..42..443M.Vizier catalog entry
  5. ^ Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065.
  6. ^ Hartkopf, William I.; Mason, Brian D. (2009). "Speckle Interferometry at Mount Wilson Observatory: Observations Obtained in 2006-2007 and 35 New Orbits". The Astronomical Journal. 138 (3): 813–826. Bibcode:2009AJ....138..813H. doi:10.1088/0004-6256/138/3/813.
  7. ^ a b c d 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. Vizier catalog entry
  8. ^ 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. arXiv:astro-ph/9911002. Bibcode:1999A&A...352..555A. Vizier catalog entry
  9. ^ 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. Vizier catalog entry
  10. ^ Wu, Yue; Singh, H. P.; Prugniel, P.; Gupta, R.; Koleva, M. (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.
  11. ^ VSX (17 December 2005). "NSV 10009". AAVSO Website. American Association of Variable Star Observers. Retrieved 28 July 2014.
  12. ^ Malkov, O. Yu.; Tamazian, V. S.; Docobo, J. A.; Chulkov, D. A. (2012). "Dynamical masses of a selected sample of orbital binaries". Astronomy & Astrophysics. 546: A69. Bibcode:2012A&A...546A..69M. doi:10.1051/0004-6361/201219774. Vizier catalog entry
  13. ^ Cvetkovic, Z.; Ninkovic, S. (2010). "On the Component Masses of Visual Binaries". Serbian Astronomical Journal. 180 (180): 71. Bibcode:2010SerAJ.180...71C. doi:10.2298/SAJ1080071C.