Are SMBHs shrouded by "super-Oort" clouds of comets and asteroids?
  The last decade has seen a dramatic confirmation that an in situ star
formation is possible inside the inner parsec of the Milky Way. Here we suggest
that giant planets, solid terrestrial-like planets, comets and asteroids may
also form in these environments, and that this may have observational
implications for Active Galactic Nuclei (AGN). Like in debris discs around main
sequence stars, collisions of large solid objects should initiate strong
fragmentation cascades. The smallest particles in such a cascade - the
microscopic dust - may provide a significant opacity. We put a number of
observational and physical constraints on AGN obscuring torii resulting from
such fragmentation cascades. We find that torii fed by fragmenting asteroids
disappear at both low and high AGN luminosities. At high luminosities, $L \sim
L_{\rm Edd}$, where $L_{\rm Edd}$ is the Eddington limit, the AGN radiation
pressure blows out the microscopic dust too rapidly. At low luminosities, on
the other hand, the AGN discs may avoid gravitational fragmentation into stars
and solids. We also note that these fragmentation cascades may be responsible
for astrophysically "large" dust particles of approximately micrometer sizes
that were postulated by some authors to explain unusual absorption properties
of the AGN torii.
