Article · Wikipedia archive · Last revised Jun 21, 2026

53 Ophiuchi

53 Ophiuchi is a multiple star system in the equatorial constellation of Ophiuchus. It is visible to the naked eye as a faint star with a combined apparent visual magnitude of 5.80. Located around 370 light years distant from the Sun based on parallax, it is moving closer to the Earth with a heliocentric radial velocity of −14 km/s. As of 2011, the visible components had an angular separation of 41.28″ along a position angle of 190°. The primary may itself be a close binary system with a separation of 0.3692″ and a magnitude difference of 3.97 at an infrared wavelength of 562 nm.

Last revised
Jun 21, 2026
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53 Ophiuchi
Observation data
Epoch J2000      Equinox J2000
Constellation Ophiuchus
Right ascension 17h 34m 36.69409s1
Declination +09° 35′ 12.1005″1
Apparent magnitude (V) 5.802 (5.82 + 7.8)3
Characteristics
Spectral type A2 V + A8 IV4
Astrometry
53 Oph A
Radial velocity (Rv)−13.9±2.95 km/s
Proper motion (μ) RA: +2.1261 mas/yr
Dec.: −8.5301 mas/yr
Parallax (π)8.8060±0.0978 mas1
Distance370 ± 4 ly
(114 ± 1 pc)
53 Oph B
Proper motion (μ) RA: +1.7946 mas/yr
Dec.: −8.1486 mas/yr
Parallax (π)8.8979±0.0413 mas6
Distance367 ± 2 ly
(112.4 ± 0.5 pc)
Details
53 Oph Aa
Mass2.50±0.057 M☉
Radius1.78 R☉
Luminosity56.4+5.3
−4.97 L☉
Surface gravity (log g)3.909 cgs
Temperature9,311+173
−1707 K
Metallicity [Fe/H]0.219 dex
Rotational velocity (v sin i)297 km/s
53 Oph B
Radius1.72+0.06
−0.036 R☉
Luminosity7.74±0.056 L☉
Temperature7,344+124
−1526 K
Rotational velocity (v sin i)1404 km/s
Other designations
f Oph, 53 Oph, HD 159480, HIP 85998, HR 6548, WDS J17346+093510
53 Oph A: BD+09°3424, GC 23824, SAO 12252610
53 Oph B: BD+09°3423, GC 23823, SAO 12252511
Database references
SIMBADdata

53 Ophiuchi is a multiple star system in the equatorial constellation of Ophiuchus. It is visible to the naked eye as a faint star with a combined apparent visual magnitude of 5.80.3 Located around 370 light years distant from the Sun based on parallax,1 it is moving closer to the Earth with a heliocentric radial velocity of −14 km/s.5 As of 2011, the visible components had an angular separation of 41.28″ along a position angle of 190°.12 The primary may itself be a close binary system with a separation of 0.3692″ and a magnitude difference of 3.97 at an infrared wavelength of 562 nm.13

The magnitude 5.823 primary, designated component Aa, is an A-type main-sequence star with a stellar classification of A2 V.4 It has 2.57 times the mass of the Sun and about 1.78 times the Sun's radius. The star is radiating 56 times the Sun's luminosity from its photosphere at an effective temperature of 9,311 K.7 The widely spaced secondary, designated component B, is a magnitude 7.83 A-type subgiant star with a class of A8 IV.4

References

References

  1. Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
  2. 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.
  3. 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.
  4. Levato, H. (1975), "Rotational velocities and spectral types for a sample of binary systems", Astronomy and Astrophysics, 19: 91, Bibcode:1975A&AS...19...91L.
  5. de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics, 546: 14, arXiv:1208.3048, Bibcode:2012A&A...546A..61D, doi:10.1051/0004-6361/201219219, S2CID 59451347, A61.
  6. Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
  7. Zorec, J.; Royer, F.; Asplund, Martin; Cassisi, Santi; Ramirez, Ivan; Melendez, Jorge; Bensby, Thomas; Feltzing, Sofia (2012), "Rotational velocities of A-type stars. IV. Evolution of rotational velocities", Astronomy and Astrophysics, 537: A120, arXiv:1201.2052, Bibcode:2012A&A...537A.120Z, doi:10.1051/0004-6361/201117691, S2CID 55586789.
  8. Pasinetti Fracassini, L. E.; et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)", Astronomy and Astrophysics, 367 (2) (Third ed.): 521–524, arXiv:astro-ph/0012289, Bibcode:2001A&A...367..521P, doi:10.1051/0004-6361:20000451, S2CID 425754.
  9. Lemke, M. (November 1989), "Abundance anomalies in main sequence A stars. I. Iron and titanium", Astronomy and Astrophysics, 225: 125–136, Bibcode:1989A&A...225..125L.
  10. "f Oph". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-06-21.
  11. "BD+09 3423". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-06-21.
  12. Mason, Brian D.; et al. (August 2011), "Speckle Interferometry at the U.S. Naval Observatory. XVII.", The Astronomical Journal, 142 (2): 4, Bibcode:2011AJ....142...46M, doi:10.1088/0004-6256/142/2/46, S2CID 250806722, 46.
  13. Horch, Elliott P.; et al. (February 2011), "Observations of Binary Stars with the Differential Speckle Survey Instrument. II. Hipparcos Stars Observed in 2010 January and June", The Astronomical Journal, 141 (2): 13, Bibcode:2011AJ....141...45H, doi:10.1088/0004-6256/141/2/45, 45.