functions in kepler.i - j

    jpl_planets  


orbital elements from http://ssd.jpl.nasa.gov/elem_planets.html  
"Mean orbit solutions from a 250 yr. least squares fit of the  
DE200 planetarty ephemeris to a Keplerian orbit where each element  
is allowed to vary linearly with time.  This solution fits the  
terrestrial planets to 25" or better, but achieves only 600" for  
Saturn.  Elements are referenced to mean ecliptic and equinox  
of J2000 at the J2000 epoch (2451545.0 JD)."  
J2000 = 2000 January 1.5  
  
WARNING: these elements are 1.5 JD later than sch_planets  
  
definitions:  
argument of perihelion = longitude of perihelion -  
                         longitude of ascending node  
mean anomaly = mean longitude - longitude of perihelion  
1 Julian century = 36525 days  
   Keyword,  defined at i/kepler.i   line 434