Just to throw a monkey wrench into the works, they could also be 'sidereal' and 'solar' (or mean solar), since 15 degrees is the rotation of the earth in one mean solar hour, and 15.04... is the rotation of the Earth in one sidereal hour. The terminology and length of a sidereal day are from Appendix I of Jean Meeus' Astronomical Algorithms, which I recommend, though it's not light reading.
Of course, this is Perl, and you could do both. Plus allow explicit user-specified values. I have not looked into the actual algorithm, though I probably should. The Astro::Coord::ECI suite (disclaimer: I'm the author) gets almanac data by successive approximation. While I'm disclaiming, I have no formal qualifications at all in computational astronomy. I remember vividly that my biggest problems implementing Astro::Coord::ECI::TLE (satellite position) were, simply stated, "Where am I?" and "What time is it?" Tom Wyant
