used to predict everything from planetary orbits to the exact time of sunset. It is considered the "antidote" to misunderstanding precise astronomical units and measurements.
Urban, S. E., & Seidelmann, P. K. (Eds.). (2013). Explanatory Supplement to the Astronomical Almanac (3rd ed.). University Science Books. [PDF, available from your library or publisher]. the explanatory supplement to the astronomical almanac pdf
If you are looking for the actual text or detailed summaries, here are the most accessible sources: Third Edition (2013/2014) used to predict everything from planetary orbits to