It looks like JPL just opensourced their MATH77 Fortran library. MATH77 is a library of Fortran 77 subroutines implementing various numerical algorithms. It was developed over decades at JPL, and contains some very high-quality and time-tested code. The code is released under a BSD-type license. There is also a C version for people who love semicolons.
- “MATH77/mathc90 Libraries Available at netlib”, July 17, 2015. [comp.lang.fortran]