The is the definitive technical reference for the theories and algorithms used to produce the annual Astronomical Almanac . Where to Find PDF Versions
It details the differences between Universal Time (UT1), Terrestrial Time (TT), and Barycentric Dynamical Time (TDB). Celestial Reference Systems: The is the definitive technical reference for the
The foundation for joint US/UK astronomical data. Terrestrial Time (TT)
The Explanatory Supplement to the Astronomical Almanac is an essential resource for anyone who uses the Astronomical Almanac. It provides a detailed understanding of the data and methods used, which is crucial for: which is crucial for: