/* Position of outer planets; straightforward from: ftp://adc.gsfc.nasa.gov/pub/adc/archives/journal_tables/A+AS/109/181: J/A+AS/109/181 Planetary ephemerides (Chapront, 1995) =============================================================================== Representation of planetary ephemerides by frequency analysis. Application to the five outer planets. CHAPRONT J. =1995A&AS..109..181C (SIMBAD/NED Reference) =============================================================================== 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**n_i*(CX_i*cos(Nu_k*t)+SX_i*sin(Nu_k*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: Nu_k = Nu_i when n_i = 0 For purely secular terms k = 0 and Nu_0 = 0 =============================================================================== (End) Patricia Bauer [CDS] 03-Oct-1994 */ #define CHAP_SCALE 1e10 /* JDs of validity period */ #define CHAP_BEGIN (2338032.5 - MJD0) /* 1689/3/19 */ #define CHAP_END (2542032.5 - MJD0) /* 2247/10/1 */ /* coding flags */ /* calculating rates increases time by about 10% * * On an HP715/75, for pluto the times per step are 0.00049 s and 0.00057 s * This method is quite fast. */ #define CHAP_GETRATE 1 typedef struct { short n; /* order of time; "-1" marks end of list */ double amp[6]; /* amplitudes of cosine and sine terms for x,y,z */ /* in original order [CX,SX,CY,SY,CZ,SZ] */ double Nu; /* Frequency Nu_k; given only at n=0 */ } chap95_rec; extern chap95_rec chap95_jupiter[]; extern chap95_rec chap95_saturn[]; extern chap95_rec chap95_uranus[]; extern chap95_rec chap95_neptune[]; extern chap95_rec chap95_pluto[]; #include "P_.h" extern int chap95 P_((double mjd, int obj, double prec, double *ret)); /* For RCS Only -- Do Not Edit * @(#) $RCSfile: chap95.h,v $ $Date: 1997/05/19 18:30:37 $ $Revision: 1.1 $ $Name: $ */