Long-term harmonic development of lunar ephemeris
Abstract
Aims:The aim of this study is to develop new analytical series representing lunar coordinates to accuracy compatible with the accuracy of the modern numerical ephemeris of the Moon.
Methods: An improved method of spectral analysis of tabulated function is used to make harmonic development of the latest long-term numerical ephemeris of the Moon LE-406 which covers a six thousand-year interval. A feature of the method is that the development is made directly to Poisson series where both amplitudes and arguments of the series' terms are high-degree polynomials of time.
Results: The new analytical development includes 42 270 Poisson series' terms of minimal amplitude equivalent to 1 cm and is valid over 1500-2500. A simplified version of the development includes 7952 series' terms of minimal amplitude equivalent to 1 m and is valid over 3000BC-3000AD. Over 1500-2500 the maximum difference between lunar coordinates calculated by means of the new analytical series and numerical ephemeris LE-406 is 3.2 m in geocentric distance, 0.0056 arcsec in ecliptic longitude, and 0.0018 arcsec in ecliptic latitude. This is 9-70 times better than the accuracy of the latest analytical theory of lunar motion ELP/MPP02, and the number of terms in the new development is less than that in ELP/MPP02.
- Publication:
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Astronomy and Astrophysics
- Pub Date:
- September 2007
- DOI:
- 10.1051/0004-6361:20077568
- Bibcode:
- 2007A&A...471.1069K
- Keywords:
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- celestial mechanics;
- methods: analytical;
- Moon