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γ Ophiuchi
Location of γ Ophiuchi (circled)
Observation data
Epoch J2000.0       Equinox J2000.0
Constellation Ophiuchus
Right ascension 17h 47m 53.55973s [1]
Declination +02° 42′ 26.2000″ [1]
Apparent magnitude (V) +3.753 [2]
Characteristics
Spectral type A0 V [3] or A1VnkA0mA0 [4]
U−B color index +0.040 [2]
B−V color index +0.033 [2]
Astrometry
Radial velocity (Rv)−7.6±0.3 [5] km/s
Proper motion (μ) RA: −24.64 [1]  mas/ yr
Dec.: −74.42 [1]  mas/ yr
Parallax (π)31.73 ± 0.21  mas [1]
Distance102.8 ± 0.7  ly
(31.5 ± 0.2  pc)
Absolute magnitude (MV)+1.26 [5]
Details
Mass2.9 [3]  M
Radius1.8 [6]  R
Luminosity29 [3]  L
Surface gravity (log g)4.03 [4]  cgs
Temperature9,506 [3]  K
Rotational velocity (v sin i)220 [7] km/s
Age184+93
−134
[7]  Myr
Other designations
Muliphen [8], γ Oph, 62 Ophiuchi, BD+19° 3564, FK5 668, GC 24162, HD 161868, HIP 87108, HR 6629, SAO 122754 [9]
Database references
SIMBAD data

Gamma Ophiuchi, Latinized from γ Ophiuchi, is a fourth-magnitude star in the constellation Ophiuchus. Together with Beta Ophiuchi, it forms the serpent-holder's right shoulder. [10] The staris visible to the naked eye with an apparent visual magnitude of +3.75. [2] Based upon an annual parallax shift of 31.73  mas as seen from Earth, it is located 103  light years from the Sun. It is moving closer to the Sun with a radial velocity of −7.6 km/s. [5]

It is known also as Muliphen, [8] [11] although at least two more stars are known with this name: Gamma Canis Majoris (often spelled as Muliphein) and Gamma Centauri (often spelled as Muhlifain). [11]

This is an A-type main sequence star with a stellar classification of A0 V. [3] Gray et al. (2003) lists a classification of A1VnkA0mA0, [4] indicating it is of type A1 V with the calcium K-line and metallic lines of an A0 star. It is approximately 184 [7] million years old and is spinning rapidly with a projected rotational velocity of 220 km/s. [7] Gamma Ophiuchi has nearly three times the mass of the Sun and 1.8 times the Sun's radius. [6] The star shines with 29 [3] times the luminosity of the Sun, which is being emitted from its outer atmosphere at an effective temperature of 9506 K. [3] 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. [3]

References

  1. ^ a b c d e van Leeuwen, F. (2007). "Validation of the New Hipparcos Reduction". Astronomy and Astrophysics. 474 (2): 653–64. arXiv: 0708.1752. Bibcode: 2007A&A...474..653V. doi: 10.1051/0004-6361:20078357. S2CID  18759600.
  2. ^ a b c d Cousins, A. W. J. (1984), "Standardisation of broad band photometry of equatorial standards", South Africa Astronomical Observatory Circular, 8: 59–67, Bibcode: 1984SAAOC...8...59C.
  3. ^ a b c d e f g h 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, S2CID  18883195
  4. ^ a b c 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. (2006). "Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 pc--The Southern Sample". The Astronomical Journal. 132 (1): 161–170. arXiv: astro-ph/0603770. Bibcode: 2006AJ....132..161G. doi: 10.1086/504637. S2CID  119476992.
  5. ^ 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, S2CID  119257644.
  6. ^ 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
  7. ^ a b c d 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, S2CID  18154947
  8. ^ a b Hinckley Allen, Richard. "LacusCurtius • Allen's Star Names — Ophiuchus". Retrieved 2017-01-03.
  9. ^ "* gam Oph". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2007-01-20.
  10. ^ Ridpath, Ian (June 28, 2018), Star Tales, Lutterworth Press, p. 189, ISBN  9780718847821.
  11. ^ a b Kaler, Jim. "Muliphen". Retrieved 2017-01-03.