  The dust disk around Beta Pic must be produced by collision or by evaporation
of orbiting Kuiper belt-like objects. Here we present the
Orbiting-Evaporating-Bodies scenario in which the disk is a gigantic
multi-cometary tail supplied by slowly evaporating bodies like Chiron. If dust
is produced by evaporation, a planet with an eccentric orbit can explain the
observed asymmetry of the disk, because the periastron distribution of the
parent bodies are then expected to be non-axisymmetric. We investigate the
consequence for the Kuiper belt-like objects of the formation and the migration
of an outer planet like Neptune in Fernandez's scheme (1982). We find that
bodies trapped in resonance with a migrating planet can significantly
evaporate, producing a Beta Pic-like disk with similar characteristics like
opening angle and asymmetry.
  We thus show that the Beta Pic disk can be a transient phenomenon. The
circumstellar disks around main sequence stars can be the signature of the
present formation and migration of outer planets.
