INDI is now using libnova to perform any required astronomical calculations by the drivers. I removed the code from indicom that used to provide some basic calculations since it is not sufficient.

A C library was required. However, libnova is a soft dependency, meaning that INDI and KStars will fully compile and function without it. If it's not available in the system, only the features and/or drivers that depend on it will be disabled. Therefore, as with cfitsio, there is no hard dependency in this situation.