开云体育

Hi,

Attached are 2 plots of the same trail, one with the old elements,
one with the new fixed ones (ie perihelion epoch, and n)


diff --git a/libastro/plans.c b/libastro/plans.c
index 9680c2a..805d88f 100644
--- a/libastro/plans.c
+++ b/libastro/plans.c
@@ -53,9 +53,10 @@ double *ret) /* ecliptic coordinates {l,b,r} at equinox of date */
inc0 = 17.097, /* inclination, deg */
Om0 = 110.297, /* long asc node, deg */
omeg0 = 115.058, /* arg of perihel, deg */
- mjp = 2459000.5 - MJD0, /* epoch of perihel */
+ mjp = 2447654.5 - MJD0, /* epoch of perihel */
mjeq = J2000, /* equinox of elements */
- n = 0.0039; /* daily motion, deg */
+ n = 0.003959; /* daily motion, deg */

double inc, Om, omeg; /* orbital elements at epoch of date */
double ma, ea, nu; /* mean, excentric and true anomaly */
[

The new ones give better continuity with Chapront's solution, which does not mean accuracy. If anyone needs better accuracy over centuries, a simple ellipse will probably not make it. So as continuity with Chapront is ensured, I think we can easily fix and keep the new elements.
--
fm

--
Dr Fran?ois Meyer Tel : (+33) 3 81 66 69 27 Mob : (+33) 6 27 28 56 83
Dir. exécutif plateforme OscIMP
Dir. LNE-LTFB, laboratoire temps-fréquence associé au LNE
Institut UTINAM / OSU Theta
41b avenue de l'Observatoire, BP1615
25010 Besancon cedex - FRANCE
** Universite de Franche-Comte ** CNRS UMR 6213 ** URA 3245