  It has been suggested to use seismic detectors on the Moon as a tool to
search for gravitational waves in an intermediate frequency range between mHz
and Hz. Employing three different spherically symmetric models for the lunar
interior, we investigate the response of the Moon to gravitational waves in
Einstein and Jordan-Brans-Dicke gravity. We find that the first
eigenfrequencies of the different models depend only weakly on the model
details, with the fundamental frequency $\nu_1$ close to 1\,ms both for
spheroidal and toroidal oscillations. In contrast, the resulting displacement
varies up to a factor two, being in the range $(2.7-5.6)\times 10^{11}/h_0$ cm
for spheroidal oscillations with amplitude $h_0$. Toroidal oscillations are
suppressed by a factor $2\pi\nu R/c$, both in Einstein gravity and in general
scalar-tensor theories.
