Perseus OB1


Perseus OB1 is an OB association in the Northern Celestial Hemisphere in the constellation Perseus. It is centered around the double cluster (NGC 869 and NGC 884),[6] and has lent its name to the Perseus Arm of the Milky Way.[8] The brightest member of the association is the blue supergiant 9 Persei.[4]

Perseus OB1
Double Clusters in Perseus.png
Double cluster at the heart of Per OB1
Credit: Chrisguidry
Observation data (J2000 epoch)
Right ascension02h 21m [1][2]
Mean distance6.0 kly (1.83 kpc)[3]
Span1,000 × 750 light years[4]
Radial velocity−43.4[5] km/s
Physical characteristics
OB stars≥65[7]
Other designationsPer OB1[1]
See also: Stellar association, Moving groups


  1. ^ a b c "Per OB1". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2020-01-15.
  2. ^ a b Sitnik, T. G. (May 2003). "The Line-of-Sight Velocities of OB Associations and Molecular Clouds in a Wide Solar Neighborhood: The Streaming Motions of Stars and Gas in the Perseus Arm". Astronomy Letters. 29: 311–320. Bibcode:2003AstL...29..311S. doi:10.1134/1.1573280.
  3. ^ Melnik, A. M.; Dambis, A. K. (2020). "Distance scale for high-luminosity stars in OB associations and in field with Gaia DR2. Spurious systematic motions". Astrophysics and Space Science. 365 (7). arXiv:2006.14649. doi:10.1007/s10509-020-03827-0. S2CID 220128144.
  4. ^ a b Crossen, Craig; Rhemann, Gerald (2012). Sky Vistas: Astronomy for Binoculars and Richest-Field Telescopes. Springer Science & Business Media. p. 93. ISBN 9783709106266.
  5. ^ Mel'Nik, A. M.; Dambis, A. K. (2009). "Kinematics of OB-associations and the new reduction of the Hipparcos data". Monthly Notices of the Royal Astronomical Society. 400 (1): 518. arXiv:0909.0618. Bibcode:2009MNRAS.400..518M. doi:10.1111/j.1365-2966.2009.15484.x.
  6. ^ a b Lee, Hsu-Tai; Lim, Jeremy (June 2008). "On the Formation of Perseus OB1 at High Galactic Latitudes". The Astrophysical Journal. 679 (2): 1352–1363. arXiv:0804.4520. Bibcode:2008ApJ...679.1352L. doi:10.1086/587801.
  7. ^ Beech, Martin; Slawson, Robert W. (December 1995). "Are There Really Blue Stragglers in Per OB1?". Astrophysics and Space Science. 234 (2): 217–221. Bibcode:1995Ap&SS.234..217B. doi:10.1007/BF00627667.
  8. ^ Inglis, Michael (2013). Observer’s Guide to Star Clusters. New York, New York: Springer Science & Business Media. p. 184. ISBN 978-1-4614-7567-5.