Planetary Ephemerides

At the present time the planetary ephemerides in the Astronomical Ephemeris and in the American Ephemeris and Nautical Almanac (both hereinafter referred to as the AE), the Astronomical Ephemeris of the U.S.S.R. and most other national almanacs have the following basis: For Mercury, Venus, Earth, and Mars the general theories of Simon Newcomb (1898a), the ephemeris of Mars including the empirical corrections determined by Ross (1917); for the five outer planets, the numerical integration of Eckert et al. (1951); the Connaissance de Temps publishes ephemerides of Mercury, Venus, Earth, and Mars based on the theories of Leverrier (1858, 1859, 1861a, b); for Jupiter, Saturn, Uranus, and Neptune the ephemerides are based on Leverrier’s (1876a, b, 1877a, b) expressions as modified by Gaillot (1904,1910, 1913). The ephemeris of Pluto is based on the numerical integration of Eckert et al. In all of the above publications the ephemeris of the Moon is now based on the Improved Lunar Ephemeris which is derived from the theory of Brown (1919). Newcomb’s theories and the numerical integration of the orbits of the five outer planets all rest primarily on the system of astronomical constants and planetary masses adopted at the Paris conferences of 1896 and 1911 {Monthly Notices Roy. Astron. Soc., 1912).