a test of the ridigity cutoff calculates as a surface os a sphere. Sphere vs individual poins are defined in input/geospace-rigidity.in
Initialization of the model:
    git checkout earth_cutoff_rigidity_model
    ./Config.pl -application=earth-cutoff-rigidity_t96
    ./Config.pl -spice-path=/nobackupp17/vtenishe/SPICE/cspice -spice-kernels=/nobackupp17/vtenishe/SPICE/Kernels
    cp input/geospace-rigidity.in .
    ./Config.pl -input=geospace-rigidity.in
    make -j