Radioastrometry: principles and accuracy.
Abstract
Radio interferometers can be used to define an astrometric system based on observations of point-like extragalactic sources (mainly quasars). It is estimated in the present paper that several hundred extragalactic objects could be observed with interferometers (at cm or mm wavelengths) to extend the radio reference frame. The ultimate position accuracy could be about 0.01 arc sec. Observations made with the Bordeaux mm-wave interferometer are presented as an example of astrometric work in the radio range. One of the results of this work is that Venus at inferior conjunction is found to have a position shift of 0.65 plus or minus 0.2 s in right ascension with respect to classical ephemeris.
- Publication:
-
Journal of Optics
- Pub Date:
- December 1979
- DOI:
- 10.1088/0150-536X/10/6/016
- Bibcode:
- 1979JOpt...10..359B
- Keywords:
-
- Astrometry;
- Radio Astronomy;
- Radio Interferometers;
- Millimeter Waves;
- Quasars;
- Radio Sources (Astronomy);
- Venus (Planet);
- Astronomy;
- Radio Astrometry