Cepheus OB1 is an OB association around the cluster NGC 7380. The region is approximately 3,400 parsecs from Earth in the constellation of Cepheus, although many of its stars lie in neighboring constellations like Cassiopeia.
| Cepheus OB1 | |
|---|---|
 NGC 7380 and Wizard nebula | |
| Observation data (J2000.0 epoch) | |
| Right ascension | 22h 29m 00s[1] |
| Declination | +56° 36′ 00″[1] |
| Distance | 3,400+220 −200 pc[2] |
| Physical characteristics | |
| Radius | 815[3] |
| Associations | |
| Constellation | Cepheus |
Cepheus OB1 contains dozens of O and B class stars, but the brightest members are cool supergiants and hypergiants such as V509 Cassiopeiae (HR 8752) and RW Cephei.[4]
| Star | Spectral type | Notes |
|---|---|---|
| RW Cephei | K2 0-Ia | Variable, one of the largest stars known |
| V354 Cephei | M2.5 Iab / M3.5 Ib | Variable, one of the largest stars known |
| DH Cephei | O5.5 V / O6 V | Binary |
| HR 8752 | G0 Ia-0 | Yellow hypergiant |
| W Cephei | K0ep-M2ep Ia + B0/B1 | Binary |
| U Lacertae | M4epIab + B | Spectroscopic binary |
| WR 152 | WN3(h) | Wolf–Rayet star |
References
edit- ^ a b "Ass Cep OB 1". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2016-10-28.
- ^ Parker, Richard J.; Crowther, Paul A.; Rate, Gemma (2020). "Unlocking Galactic Wolf–Rayet stars with Gaia DR2 – II. Cluster and association membership". Monthly Notices of the Royal Astronomical Society. 495 (1): 1209–1226. arXiv:2005.02533. Bibcode:2020MNRAS.495.1209R. doi:10.1093/mnras/staa1290. S2CID 218516882.
- ^ Garmany, C. D.; Stencel, R. E. (1992). "Galactic OB associations in the northern Milky Way Galaxy. I - Longitudes 55 deg to 150 deg". Astronomy and Astrophysics Supplement Series. 94: 211. Bibcode:1992A&AS...94..211G.
- ^ Humphreys, R. M. (1978). "Studies of luminous stars in nearby galaxies. I. Supergiants and O stars in the Milky Way". The Astrophysical Journal Supplement Series. 38: 309. Bibcode:1978ApJS...38..309H. doi:10.1086/190559.