[Kstars-devel] Ephemeris engine?

[Daniel-Marian Baboiu]

I'm starting to look into eclipse prediction for kstars, although I
won't start actual coding in less than 3 weeks. I had a project a few
years ago, concerning Moon eclipses, and I had some success - my
prediction for contacts and maximum phase were within a few minutes (~3)
from published values. For Sun eclipses and star occultations, it is
more complicated - simply looking for conjunctions won't do.

So, the first step is to understand what is the ephemeris engine behind
kstars?

The most precise uses JPL data, DE405 (with long version, DE406), but
there is also the older standard, DE200. Derived from these there are
VSOP87 and EPL2000-82 (from DE200) and the Swiss Ephemeris (compressed
and extended version of DE206). All these are more precise, but require
additional data files (some quite large). The eclipse prediction from
NASA are based on VSOP87/EPL2000-82. Some simplified versions also exist
.
DMB