Yesterday I was asked for an illustration showing the Cassini trajectory through the Saturnian system, but I only found incomplete scetches, mess up with apokronia date and so on.
Maybe someone else is also interested in, so I have calculated a set of Cartesian Kronocentric Positions and made a Excel sheet for convenience.
This look like that:
Click to view attachment
That is done via:
1. Calculating the kronocentric (saturnocentric) right ascension, declination and distances with the famous JPL HORIZON ephemeris calculator.
2. Converting these data to Cartesian (XYZ) positions via spherical trigonometry. How to do that is explained here, for example:
http://www.projectrho.com/smap03.html
Those data are kronocentric (not barycentric, but due to the mass of saturn and the relative small influence of the moons there is only a small difference), depending on the actual Saturnian Equator and the vernal equinox (the terrestrial one, because that is standard). In some cases other reference frames like the Saturnian Laplacian plane, the Terrestric or Saturnian ecliptic are chosen, so several published scetches looks different.
The data are enclosed in two parts
Cassini Kronocentric Positions Jun 2004 - Jun 2010.part1.txt
and
Cassini Kronocentric Positions Jun 2004 - Jun 2010.part2.txt (next post) because the file is larger than 1 MB
Rename both files to .rar and expand them.