Membership in the young open cluster NGC 654.
Abstract
Relative proper motions with an average standard error of + or 0.07 arcsec/century in each coordinate have been determined for 186 stars in the region of the young open cluster NGC 654. Of these stars 60 are found to be probable members, including the A0 Ib supergiant BD +61 deg 315. The F5 Ia MK standard HD 10494 tentatively appears to be a probable member. With an adopted absorption ratio of 3.0, the corrected distance modulus is 11.9 + or - 0.3 magnitudes or a distance of 2400 pc. Derived absolute visual magnitudes and intrinsic (B-V) colors for the supergiants are given. Three additional bright stars are presented as possible B-A Ib supergiants. The known variable reddening across the cluster is probably due to foreground dust rather than to dust left over from the period of star formation.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- February 1977
- Bibcode:
- 1977A&A....54..803S
- Keywords:
-
- Astronomical Catalogs;
- Open Clusters;
- Stellar Motions;
- Supergiant Stars;
- A Stars;
- B Stars;
- Cosmic Dust;
- Data Reduction;
- Interstellar Extinction;
- Probability Theory;
- Ubv Spectra;
- Astronomy