  Polluted white dwarfs offer a unique way to study the bulk compositions of
exoplanetary material, but it is not always clear if this material originates
from comets, asteroids, moons, or planets. We combine N-body simulations with
an analytical model to assess the prevalence of extrasolar moons as white dwarf
(WD) polluters. Using a sample of observed polluted white dwarfs we find that
the extrapolated parent body masses of the polluters are often more consistent
with those of many solar system moons, rather than solar-like asteroids. We
provide a framework for estimating the fraction of white dwarfs currently
undergoing observable moon accretion based on results from simulated white
dwarf planetary and moon systems. Focusing on a three-planet white dwarf system
of Super-Earth to Neptune-mass bodies, we find that we could expect about one
percent of such systems to be currently undergoing moon accretions as opposed
to asteroid accretion.
