source: Sophya/trunk/SophyaExt/XephemAstroLib/chap95.h

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fichiers de Xephem 3.7.5 update, cmv 21/09/2011

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1/* Position of outer planets; straightforward from:
2ftp://adc.gsfc.nasa.gov/pub/adc/archives/journal_tables/A+AS/109/181:
3
4J/A+AS/109/181 Planetary ephemerides (Chapront, 1995)
5===============================================================================
6Representation of planetary ephemerides by frequency analysis. Application to
7the five outer planets.
8 CHAPRONT J.
9 <Astron. Astrophys. Suppl. Ser. 109, 181 (1995)>
10 =1995A&AS..109..181C (SIMBAD/NED Reference)
11===============================================================================
12
13Keywords: ephemerides - planets and satellites: general - methods: numerical
14
15Contents:
16 Heliocentric equatorial rectangular coordinates of the five outer planets
17 (X, Y and Z). The source is based on DE200 (tables 4 to 7) or a reconstruction
18 of DE200 by numerical integration (tables 9 to 13). The reference frame is
19 the mean equator and equinox J2000 of DE200.
20
21 The general formulation of the series X is:
22 X = SUM[i=1,Records] T**n_i*(CX_i*cos(Nu_k*t)+SX_i*sin(Nu_k*t))
23 The formulation is identical for Y and Z.
24 T is the time (TDB) in Julian centuries from J2000:
25 T = (JulianDate - 2451545.0)/36525
26 t is the time (TDB) in Julian years from J2000:
27 t = (JulianDate - 2451545.0)/365.25
28 Nu is the frequency. Frequencies are identical for all terms of rank k:
29 Nu_k = Nu_i when n_i = 0
30 For purely secular terms k = 0 and Nu_0 = 0
31
32===============================================================================
33(End) Patricia Bauer [CDS] 03-Oct-1994
34*/
35
36#define CHAP_SCALE 1e10
37
38/* JDs of validity period */
39#define CHAP_BEGIN (2338032.5 - MJD0) /* 1689/3/19 */
40#define CHAP_END (2542032.5 - MJD0) /* 2247/10/1 */
41
42/* coding flags */
43/* calculating rates increases time by about 10%
44 *
45 * On an HP715/75, for pluto the times per step are 0.00049 s and 0.00057 s
46 * This method is quite fast.
47 */
48#define CHAP_GETRATE 1
49
50typedef struct {
51 short n; /* order of time; "-1" marks end of list */
52 double amp[6]; /* amplitudes of cosine and sine terms for x,y,z */
53 /* in original order [CX,SX,CY,SY,CZ,SZ] */
54 double Nu; /* Frequency Nu_k; given only at n=0 */
55} chap95_rec;
56
57extern chap95_rec chap95_jupiter[];
58extern chap95_rec chap95_saturn[];
59extern chap95_rec chap95_uranus[];
60extern chap95_rec chap95_neptune[];
61extern chap95_rec chap95_pluto[];
62
63extern int chap95 (double m, int obj, double prec, double *ret);
64
65
66/* For RCS Only -- Do Not Edit
67 * @(#) $RCSfile: chap95.h,v $ $Date: 2011-09-21 16:17:48 $ $Revision: 1.9 $ $Name: not supported by cvs2svn $
68 */
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