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J/A+AS/109/181         Planetary ephemerides                    (Chapront, 1995)
Representation of planetary ephemerides by frequency analysis. Application to
the five outer planets.
    Chapront J.
   <Astron. Astrophys. Suppl. Ser. 109, 181 (1995)>
   =1995A&AS..109..181C
ADC_Keywords: Ephemerides

Keywords: ephemerides - planets and satellites: general - methods: numerical


Contents:
  Heliocentric equatorial rectangular coordinates of the five outer planets
  (X, Y and Z). The source is based on DE200 (tables 4 to 7) or a 
  reconstruction of DE200 by numerical integration (tables 9 to 13). 
  The reference frame is the mean equator and equinox J2000 of DE200.

  The general formulation of the series X is:
       X = SUM[i=1,Records] T**ni*(CXi*cos(Nuk*t)+SXi*sin(Nuk*t))

  The formulation is identical for Y and Z.

  T is the time (TDB) in Julian centuries from J2000:
        T = (JulianDate - 2451545.0)/36525

  t is the time (TDB) in Julian years from J2000:
        t = (JulianDate - 2451545.0)/365.25

  Nu is the frequency. Frequencies are identical for all terms of rank k:
                Nuk = Nui when ni = 0
                For purely secular terms k = 0 and Nu0 = 0

File Summary:

       FileName      Lrecl  Records   Explanations

ReadMe            80        .   This file
table4.dat       128      163  *Coefficients for Jupiter
table5.dat       128      141  *Coefficients for Saturn
table6.dat       128      103  *Coefficients for Uranus
table7.dat       128       61  *Coefficients for Neptune
table9.dat       128      216  *Coefficients for Jupiter
table10.dat      128      192  *Coefficients for Saturn
table11.dat      128      129  *Coefficients for Uranus
table12.dat      128      117  *Coefficients for Neptune
table13.dat      128       98  *Coefficients for Pluto

Note on table4.dat, table5.dat, table6.dat, table7.dat:
    The source is based on DE200. The time interval covers the 
    Julian dates 2378640.5 (1800/5/25) to 2469640.5 (2049/7/18). The
    precision of the approximation is below 0.004 arcsecond for all the
    planets, in angular variables. The number of terms is distributed as
    follows: One constant term, N secular terms, Q0 periodic (Fourier)
    terms, Q1 and Q2 mixed (Poisson) terms of degree 1 and 2 in time.
    -----------------------------------------------------
    Table (Planet)  N       Q_0         Q_1         Q_2
    -----------------------------------------------------
    4     (Jupiter) 3       135         22          2
    5     (Saturn)  3       118         17          2
    6     (Uranus)  1       78          18          5
    7     (Neptune) 1       48          10          1
    -----------------------------------------------------
Note on table9.dat, table10.dat, table11.dat, table12.dat, table13.dat:
    The source is based on a reconstruction of DE200. 
    The time interval covers the Julian dates 2338032.5 (1689/3/19) to
    2542032.5 (2247/10/1). The precision of the approximation is below
    0.02 arcsecond for all the planets, in angular variables. The number
    of terms is distributed as follows (see note(1)):
    -----------------------------------------------------
    Table (Planet)   N      Q_0         Q_1         Q_2
    -----------------------------------------------------
    9     (Jupiter)  1      154         44          16
    10    (Saturn)   1      130         41          19
    11    (Uranus)   1      102         19          6
    12    (Neptune)  1       96         15          4
    13    (Pluto)    1       66         20          10
    -----------------------------------------------------


See also:
    VI/87 : Planetary Ephemerides of all nine planets (Chapront+ 1996)


Byte-by-byte Description of file: table*.dat

   Bytes Format  Units   Label    Explanations

   2-  5  I4     ---     k        ? Rank of the frequency
       9  I1     ---     n        Power of time (1)
  13- 27  F15.0  ---     CX       Variable X - Cosine term (2)
  28- 42  F15.0  ---     SX       ? Variable X - Sine term (2)
  45- 59  F15.0  ---     CY       Variable Y - Cosine term (2)
  60- 74  F15.0  ---     SY       ? Variable Y - Sine term (2)
  77- 91  F15.0  ---     CZ       Variable Z - Cosine term (2)
  92-106  F15.0  ---     SZ       ? Variable Z - Sine term (2)
 110-128  F19.16 rad/yr  Nu       ? Frequency

Note (1): If n=0 the term is purely periodic (Fourier) or constant.
          If n=1,2 or 3 the term is mixed (Poisson) or secular, 
          of degree 1, 2 or 3 with respect to time
Note (2): Units are:
     1e-10 AU       if n=0,
     1e-10 AU/Cy    if n=1,
     1e-10 AU/Cy2 if n=2,
     1e-10 AU/Cy3 if n=3

(End)                                           Patricia Bauer [CDS] 03-Oct-1994