In addition to possible motion corrections, Geocentric Coordinates are necessary for ascertaining equinox data. After all, the equinox is defined wrt the Earth's center. Switching to a geocentric coordinate system (RA/Dec and/or Ecliptic) is a good idea. I believe this alone can account for most of the equinox timing errors.
In addition to possible motion corrections, Geocentric Coordinates are necessary for ascertaining equinox data. After all, the equinox is defined wrt the Earth's center. Switching to a geocentric coordinate system (RA/Dec and/or Ecliptic) is a good idea. I believe this alone can account for most of the equinox timing errors.