Too many arguments at /usr/local/share/perl/5.26.1/Astro/SpaceElevator.pm line 204.
# first we check to see if the sun has risen over the base station.
my (undef, $elevation, undef) = $base->azel($sun, 1); # line 204
azel is a method of Astro::Coords::ECI that only takes one arg (the object $sun). However due to the nature of the code and the extra arg I suspect he meant to call azel_offset, where the "1" refers to the upper limb of the sun, to compute sunrise:
my (undef, $elevation, undef) = $base->azel_offset($sun, 1); # line 20