The distant globular clusters Palomar 14 and Palomar 15.
Abstract
Star counts and color-magnitude diagrams from BV photographic plates obtained using the Ross f/3.67 corrector on the 5-m Hale telescope on July 12-13, 1983, are presented for the distant halo globular clusters Pal 14 and Pal 15. The distance from the Galactic center, core radius, and tidal radius of Pal 14 are found to be 70 kpc, 15 pc, and 93 pc; the corresponding values for Pal 15 are about 60 kpc, 25 pc, and 100 pc, giving it the largest core and lowest central concentration known for a globular cluster. Pal 15 is also shown to have a completely blue horizontal branch which is unique in globular clusters of the outer Galactic halo. The coordinates of Pal 15 are given as alpha = 16 h 57.3 min and delta = -00 deg 28.25 arcmin (1950), or about 4.5 arcmin west of the position given by Kukarkin (1974).
- Publication:
-
The Astronomical Journal
- Pub Date:
- December 1984
- DOI:
- Bibcode:
- 1984AJ.....89.1816H
- Keywords:
-
- Globular Clusters;
- Stellar Color;
- Stellar Magnitude;
- Stellar Spectrophotometry;
- Astronomical Photography;
- Telescopes;
- Astronomy