Hello

I recently bought a copy of Jean Meeus' "Astronomical Algorithms" from
Willmann-Bell, but I find its methodology rather outdated and very
light on explanations. It looks like it just has algorithms, without
presenting a clear description of any of the underlying phenomena. I'm
trying to gather some alternative references that we can refer to
whenever we need to check correctness of code, or look to understand
something. Here's one seemingly clear IAU circular from 2005:

http://aa.usno.navy.mil/publications/docs/Circular_179.pdf

If you know any other references to replace Meeus, please do suggest.

Regards
Akarsh