Error minimization of polynomial approximation of Delta T
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The difference between Universal time (UT) and Dynamical time (TD), known as Delta T (ΔT) is tabulated for the first day of each year in the Astronomical Almanac. During the last four centuries it is found that there are large differences between its values for two consecutive years. Polynomial approximations have been developed to obtain the values of ΔT for any time of a year for the period AD 1620 to AD 2000 (Meeu 2000) as no dynamical theories describe the variations in ΔT. In this work, a new set of polynomials for ΔT is obtained for the period AD 1620 to AD 2007 that is found to produce better results compared to previous attempts.
Key wordsDelta T polynomial approximation Dynamical time Universal time
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