| | |
| | |
Stat |
Members: 3660 Articles: 2'599'751 Articles rated: 2609
10 November 2024 |
|
| | | |
|
Article overview
| |
|
Hipparcos Parallaxes and Proper Motions of Cepheids and their Implications | M. W. Feast
; P. A. Whitelock
; | Date: |
10 Jun 1997 | Subject: | astro-ph | Affiliation: | University Cape Town) and P. A. Whitelock (South African Astronomical Observatory | Abstract: | A summary is given of an analysis of the Hipparcos trigonometrical parallaxes and proper motions of classical Cepheids. It is possible for the first time to derive zero-points for the period-luminosity and period-luminosity-colour relations from parallaxes alone, avoiding the problems of less direct methods. The results imply an increase of 8 to 10 percent in the extragalactic distance scale based on Cepheids. The proper motions are used to derive the constants of galactic rotation. Comparison with radial velocity data leads to a confirmation of the Cepheid distance scale derived from the parallaxes and indicates a kinematic distance to the galactic centre of 8.5 +/- 0.5 kpc. From the new Cepheid distances to the LMC and M31, the absolute magnitude of RR Lyrae variables in metal-poor globular clusters is derived. Applying this to data on metal-poor clusters in our own Galaxy leads to an age of about 11 Gyr for these clusters, considerably less than previously thought. Other evidence from Hipparcos on these matters is briefly reviewed and it is suggested that the Cepheid results currently provide the most reliable scale on which to base distances and ages. | Source: | arXiv, astro-ph/9706097 | Services: | Forum | Review | PDF | Favorites |
|
|
No review found.
Did you like this article?
Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.
|
| |
|
|
|