Lunar and Solar Ephemerides appropriate for historical calculations
Planetary and Lunar Ephemerides DE406 of Caltech's Jet Propulsion Laboratory
Planetary and Lunar Ephemerides DE406 of Caltech's Jet Propulsion Laboratory (JPL)
The DE406 ephemeris is a "long-time ephemeris" which neither includes nutations nor librations.
Coordinates of the sun, moon and the nine major planets can be calculated for dates
between -3001 Feb 4 and +3000 May 5 referring to the International Celestial Reference Frame (ICRF).
These ephemerides result from a least-squares adjustment of a previously existing ephemeris
to a variety of observational data, followed by a numerical integration of the
dynamical equations of motion that describe the gravitational physics of the solar system. The
final phase of the ephemeris creation process has there three main ingredients:
It is mainly the accuracy of the initial conditions and dynamical constants that
determine the accuracy of modern-day ephemerides. The values of the initial conditions
and constants are determined by their least-square fitting to observational data. The
accuracy of this adjustment, and thus of the ephemerides themselves, depends primarily
on the accuracy of the observational data.
More details about the JPL ephemerides can be found in the following references:
Ephemerides VSOP2000
The VSOP2000 ephemerides have been constructed at the Institut de mécanique céleste et
de calcul des éphémérides (IMCCE) in Paris. It
is an analytical solution of the motion of the planets Mercury, Venus, Earth, Mars, Jupiter,
Saturn, Uranus, Neptune and the Earth-Moon Barycenter. Rectangular heliocentric coordinates
for the planets and geocentric coordinates for the moon are computed to 8th
order of the masses with:
In the data files, the rectangular coordinates are given as Poisson series, referring to the
dynamical equinox and ecliptic of the year 2000 (J2000). More details about the
construction of the VSOP2000 ephemerides can be found in:
X. Moisson & P. Bretagnon, Analytical Planetary solution VSOP2000, Celestial Mechanics and
Dynamical Astronomy 80 (2001), 205-213.
The VSOP2000 ephemerides recently have become available
here.
Lunar Solution ELP/MPP02
ELP/MPP02 is a semi-analytical solution for the orbital motion of the Moon.
It contains the following components:
The constants of this lunar ephemeris have been fitted to the numerical integration DE406 of
the Jet Propulsion Laboratory. The ELP/MPP02 ephemeris includes 45053 Poisson series' terms
and is valid from 3000 BC to 3000 AD.
More details about the ephemeris construction can be found in
the following references:
LEA
Along with the construction of purely analytical or semi-analytical theories (e.g. ELP/MPP02) of the lunar motion
and the development of purely numerical lunar ephemeris (e.g. DE406) a combined approach can
be used. Such an approach was used for the construction of the LEA-406b lunar ephemeris in Moscow.
A spectral analysis of values for lunar coordinates precalculated with a small sampling step on the
basis of the latest long-term numerical ephemeris of the moon (DE405/406). The form of the resulting
series is very similar to that given by the modern analytical theories of the lunar motion. It keeps
all the advantages of the latter, but the accuracy proves to be compatible to the
accuracy of the source numerical ephemeris.
The LEA-406b ephemeris includes 7952 Poisson series' terms and is valid from 3000 BC to 3000 AD.
More details about the LEA406 ephemerides can be found in the following reference:
S. M. Kudryavtsev, Long-term harmonic development of lunar ephemeris, Astronomy & Astrophysics 471 (2007),
1069-1075, online accessible here.
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Created by
Rita Gautschy