  In 1975 Ogg offered a bottle of Jack Daniels for an explanation of the fact
that the prime divisors of the order of the monster are the primes p for which
the characteristic p supersingular j-invariants are all defined over the field
with p elements. This coincidence is often suggested to be the first hint of
monstrous moonshine, the deep unexpected interplay between the monster and
modular functions. We revisit Ogg's problem, and we point out (using existing
tools) that the moonshine functions for order p elements give the set of
characteristic p supersingular j-invariants (apart from 0 and 1728).
Furthermore, we discuss this coincidence of the two seemingly unrelated sets of
primes using the first principles of moonshine.
