This has just been announced in comp.lang.fortran, but I think it merits mention in this forum as well.
NASA's Copernicus spacecraft trajectory optimization program has been largely rewritten in Modern Fortran and the effort was reported here:
https://doi.org/10.2514/6.2018-1451
PDF link here:
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20180000413.pdf
I think high praise is due for this kind of effort nowadays, when we are constantly been pressed to interface Fortran codes with c/c++/python API's.