  We use three-dimensional distributions of classical Cepheids and RR~Lyrae
stars in the Small Magellanic Cloud (SMC) to model the stellar density
distribution of a young and old stellar population in that galaxy. We use these
models to estimate the microlensing self-lensing optical depth to the SMC,
which is in excellent agreement with the observations. Our models are
consistent with the total stellar mass of the SMC of about 1.0 x 10^9 MSun
under the assumption that all microlensing events toward this galaxy are caused
by self-lensing. We also calculate the expected event rates and estimate that
future large-scale surveys, like the Large Synoptic Survey Telescope (LSST),
will be able to detect up to a few dozen microlensing events in the SMC
annually. If the planet frequency in the SMC is similar to that in the Milky
Way, a few extragalactic planets can be detected over the course of the LSST
survey, provided significant changes in the SMC observing strategy are devised.
A relatively small investment of LSST resources can give us a unique probe of
the population of extragalactic exoplanets.
