Reference Systems #77
Description
I refer you to Chapter 3 of the Explanatory Supplement to the Astronomical Almanac entitled "Celestial Reference Systems". This chapter shows that the sky coords implemented in this package are a subset of a celestial reference system. So I suggest that this package be expanded to include celestial reference systems or subsumed by such a package. A celestial reference package will eventually be needed to support a complete Astrometry.jl packaage.