Polynomial Approximations for the Correction Delta T = E.T.- U.T. in the Period 1800-1975
Abstract
Polynomial approximations for the empirical difference between Ephemeris and Universal Time are discussed in order to provide simple arithmetic means for computing purposes. The entire period 1972.6-1978.5 can be covered by a 12th degree polynomial with a mean error of less than one second. All coefficients are significant values well above the 3 sigma level of the mean coefficient errors. Coefficients, mean errors, and maximal residuals for polynomials of degree 8 to 16 are given as well as least-squares solutions fitting low-degree expressions to some smaller time intervals.
- Publication:
-
Acta Astronomica
- Pub Date:
- 1979
- Bibcode:
- 1979AcA....29..101S
- Keywords:
-
- Ephemeris Time;
- Error Correcting Devices;
- Polynomials;
- Universal Time;
- Approximation;
- Least Squares Method;
- Long Term Effects;
- Tables (Data);
- Astronomy