An analysis of lunar occultations in the years 1943 - 1974 for corrections to the constants in Brown's theory, the right ascension system of the FK4, and Watts' lunar-profile datum.
Abstract
The times of 62,000 occultations of stars by the moon observed during 1943-1974 are analyzed to determine corrections to the lunar ephemeris j = 2 (based on Brown's (1919) theory), the right-ascension system of the fundamental star catalog FK4, and the datum of the lunar profile in Watts' (1963) charts. The method of reduction and analysis of the occultations is given in some detail. The value of -13 arcsec T-squared is adopted for the tidal term in the moon's mean longitude, and no clear evidence is found for any divergence between the dynamical and atomic time scales. After removing all the corrections found in this analysis, quasi-periodic fluctuations, amounting to 0.2 arcsec, still remain in the residuals; these are ascribed to the truncation of planetary terms in Brown's theory.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- April 1979
- DOI:
- 10.1093/mnras/187.1.41
- Bibcode:
- 1979MNRAS.187...41M
- Keywords:
-
- Data Reduction;
- Lunar Occultation;
- Stellar Occultation;
- Astronomical Catalogs;
- Ephemeris Time;
- Universal Time;
- Visual Observation;
- Astronomy;
- Ephemerides:Moon;
- Lunar Theory