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Ophiuchus (abbr. Oph, gen. Ophiuchi)





The Serpent-Bearer, the mythical healer Aesculapius (his snaked-entwined staff, the caduceus, is the physician's symbol. Ophiuchus is a large constellation, in the shape of a huge rough pentagon, mostly of the southern hemisphere, south of Hercules and west of Serpens (Caput). It is replete with bright globular clusters. See below for details of the constellation's brightest stars and interesting deep sky objects.


Ophiuchus constellation
Ophiuchus. © 2003 Torsten Bronger.
Copied here under the terms of the GNU Free Documentation License



Stars brighter than magnitude 4.0
Star Visual
mag.
Abs.
mag.
Spectral
type
Distance
(lt-yr)
R.A. (h m s) Dec. ( ° ' '' )
Alpha (Rasalhague) 2.08 1.30 A5III 47 17 34 56 +12 33 36
Eta (Sabik) 2.43 0.37 A2V 84 17 10 23 -15 43 30
Zeta (Han) 2.54 -3.20 O9.5Vn 458 16 37 09 -10 34 02
Delta (Yed Prior) 2.73 -0.86 M0.5III 170 16 14 21 -03 41 39
Beta (Cebelrai) 2.76 0.76 K2III 82 17 43 28 +04 34 02
Kappa 3.19 1.08 K2III 86 16 57 40 +09 22 30
Epsilon (Yed Posterior) 3.23 0.64 G9.5IIIbCN 108 16 18 19 -04 41 33
Theta 3.27 -2.92 B2IV 563 17 22 00 -24 59 58
Nu 3.32 -0.04 K0IIIaCN 153 17 59 01 -09 46 25
72 3.71 1.68 A4IVs 83 18 07 21 +09 33 50
Gamma 3.75 1.43 A0V 95 17 47 53 +02 42 26
Lambda (Marfik) 3.82 0.28 A0V+A4V 166 16 30 55 +01 59 02
67 3.93 -4.26 B5Ib 1,420 18 00 39 +02 55 53


Other objects of interest
Name Type of Object Notes
Barnard's Star star See separate entry
Rho Oph star A multiple star, N of Antares. Small telescopes reveal two B stars of magnitude 5.02 and 5.92, each with an eighth magnitude companion. These four stars form a V-shaped group. Rho Oph itself is embedded in a nebulosity, IC 4604
Kepler's Star supernova See separate entry
NGC 6572 planetary nebula A bright oval disk that makes a good target for small telescopes at high
magnification. Magnitude 9.0; diameter 11'; R.A. 18h 12.1m, Dec. +06° 51.4'
IC 4665 open cluster In the same field as Beta Oph, binoculars show about 20 stars of seventh magnitude and fainter stars scattered over an area of about 1°. Magnitude 4.2; diameter 41'; R.A. 17h 46.3m, Dec. +05° 43'
NGC 6633 open cluster More than 60 members. Magnitude 4.6; diameter 27'; R.A. 18h 27.7m, Dec. +06° 34'
M9 (NGC 6333) globular cluster Magnitude 7.9; diameter 9.3'; distance 5,500 light-years; R.A. 17h 19.2m, Dec. -18° 31'
M10 (NGC 6254) globular cluster Together with M12, the most prominent of the globulars in Ophiuchus. Both are visible to the naked eye. Binoculars or a small telescope show them as misty patches. Magnitude 6.6; diameter 15.1'; R.A. 16h 57.1m, Dec. -04° 06'
M12 (NGC 6218) globular cluster Slightly larger but fainter than M10. Magnitude 6.6; diameter 14.5'; R.A. 16h 47.2m, Dec. -01° 57'
M14 (NGC 6402) globular cluster A less condensed center with a slightly elliptical shape. Magnitude 7.6; diameter 11.7'; R.A. 17h 37.6m Dec. -03° 15'
M19 (NGC 6273) globular cluster The most oblate known globular cluster. Magnitude 7.1; distance: 27,000 light-years; R.A. 17h 02.6m, Dec. -26° 16'
M62 (NGC 6266) globular cluster The most irregularly-shaped known globular cluster. Magnitude 6.6; diameter 14.1; R.A. 17h 01.2m, Dec. -30° 07'
M107 (NGC 6171) globular cluster Smaller and fainter than M 10 or M12 and, unusually for globulars, contains dark regions. Magnitude 8.1; diameter 10.0'; R.A. 16h 32.5m, Dec. +03° 13'


Constellations
Andromeda | Antlia | Apus | Aquarius | Aquila | Ara | Aries | Auriga | Bootes | Caelum | Camelopardalis | Cancer | Canes Venatici | Canis Major | Canis Minor | Capricornus | Carina | Cassiopeia | Centaurus | Cepheus | Cetus | Chamaeleon | Circinus | Columba | Coma Berenices | Corona Austrina | Corona Borealis | Corvus | Crater | Crux | Cygnus | Delphinus | Dorado | Draco | Equuleus | Eridanus | Fornax | Gemini | Grus | Hercules | Horologium | Hydra | Hydrus | Indus | Lacerta | Leo | Leo Minor | Lepus | Libra | Lupus | Lynx | Lyra | Mensa | Microscopium | Monoceros | Musca | Norma | Octans | Ophiuchus | Orion | Pavo | Pegasus | Perseus | Phoenix | Pictor | Pisces | Piscis Austrinus | Puppis | Pyxis | Reticulum | Sagitta | Sagittarius | Scorpius | Sculptor | Scutum | Serpens | Sextans | Taurus | Telescopium | Triangulum | Triangulum Australe | Tucana | Ursa Major | Ursa Minor | Vela | Virgo | Volans | Vulpecula


Related categories

   • NOTABLE STARS
   • NEBULAE AND STAR CLUSTERS
   • GALAXIES