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Problem in generating ephemeris data

  1. Mar 25, 2015 #1

    I' having an hard time with the following issue.

    I've made some routines to calculate the ephemeris from Earth to Neptune with VSOP87C - referred to the mean equinox and ecliptic of date, I supose.
    So, the data I receive, is already precessed to the mean equator and ecliptic of any date.

    Then, I wrote the code for calculating the position of Pluto, with Pluto95 theory - these coordinates are referred to the mean equinox and ecliptic of J2000 however.

    To complicate things, VSOP87 is not in the FK5 frame... And according to Meeus, we must make first the corrections of light time before converting them to FK5.

    So my question is: how do get the position of Pluto into the VSOP87 frame (mean equinox and ecliptic of date, no FK5) to perform the calculations?

    The same thing happens with the Moon - with ELP82 theory.

    I'm really stuck... And I need help with the math in this one...

    Kind regards,

  2. jcsd
  3. Mar 30, 2015 #2
    Thanks for the post! This is an automated courtesy bump. Sorry you aren't generating responses at the moment. Do you have any further information, come to any new conclusions or is it possible to reword the post?
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