Gamma Ophiuchi

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γ Ophiuchi
Diagram showing star positions and boundaries of the Ophiuchus constellation and its surroundings
Cercle rouge 100%.svg

Location of γ Ophiuchi (circled)
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Ophiuchus
Right ascension 17h 47m 53.57s
Declination +02° 42′ 26.9″
Apparent magnitude (V) +3.75
Characteristics
Spectral type A0 V[1]
Astrometry
Distance 95 ly
(29.14 pc)
Absolute magnitude (MV) +1.43
Details
Mass 2.9[1] M
Radius 1.8[2] R
Luminosity 29[1] L
Temperature 9,506[1] K
Rotational velocity (v sin i) 220[3] km/s
Age 184+93
−134
[3] Myr
Other designations
Al Durajah, Tsung Ching, 62 Ophiuchi, BD +09 3564, FK5 668, GC 24162, HD 161868, HIP 87108, HR 6771, SAO 122754.[4]

Gamma Ophiuchi (γ Oph, γ Ophiuchi) is a fourth-magnitude star in the constellation Ophiuchus. It is located about 95 light-years from Earth. The system has an age of roughly 184 million years.[1]

This is an A-type main sequence star with a stellar classification of A0 V.[1] It has nearly three times the mass of the Sun and 1.8 times the Sun's radius.[2] The star shines with 29[1] times the luminosity of the Sun, which is being emitted from its outer atmosphere at an effective temperature of 9,506 K.[1] It is radiating an excess emission of infrared, suggesting the presence of a circumstellar disk of dust at an orbital radius of 64 AU from the host star.[1]

References[edit]

  1. ^ a b c d e f g h i Wyatt, M. C. et al. (July 2007), "Steady State Evolution of Debris Disks around A Stars", The Astrophysical Journal 663 (1): 365–382, arXiv:astro-ph/0703608, Bibcode:2007ApJ...663..365W, doi:10.1086/518404 
  2. ^ a b Malagnini, M. L.; Morossi, C. (November 1990), "Accurate absolute luminosities, effective temperatures, radii, masses and surface gravities for a selected sample of field stars", Astronomy and Astrophysics Supplement Series 85 (3): 1015–1019, Bibcode:1990A&AS...85.1015M 
  3. ^ a b Song, Inseok et al. (February 2001), "Ages of A-Type Vega-like Stars from uvbyβ Photometry", The Astrophysical Journal 546 (1): 352–357, arXiv:astro-ph/0010102, Bibcode:2001ApJ...546..352S, doi:10.1086/318269 
  4. ^ "HD 161868 -- Star", SIMBAD Astronomical Database, retrieved 2007-01-20