Galactic rotation and the precession constant
Abstract
The effect of high proper motion stars on the determination of the precession constant is discussed, and an improved technique of determining the stellar velocity field in the solar neighbourhood is described. The technique is applied to stars in the FK4 and AGK3, and the results interpreted as implying an apparent rotation of the nearby stars in the opposite direction to galactic rotation. There is uncertainty in allowing for this counter-rotation, but a value of Oor s constant B in the region of - I"'00 per century is suggested. Only the distant Bo stars in the AGK3 seem consistent with a pattern of differential galactic rotation and a value of A in the region of +0"' 25 per century is also suggested. Since evidence from other sources indicates that A is unlikely to be less than - jB, these determinations are probably still influenced however by the motions of nearby stars. The investigation provides general support for the kind of correction to the precession constant proposed by Fricke and Vasilevskis and Klemola, and implies that of the motion of the equinox is confused by a stellar component.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- 1972
- DOI:
- 10.1093/mnras/159.3.289
- Bibcode:
- 1972MNRAS.159..289C