Methods for Truncating Disks

  1. A passing star tidally strips the Kuiper belt image
    (Melita el al. 2001; Kobayashi & Ida 2001; Levison, Morbidelli, & Dones 2004).

  2. An edge formed prior to planetesimal formation due to aerodynamic drag. image
    (Youdin & Shu 2002)

  3. An edge formed during planet accretion due to size-dependent radial gas drag. image
    (Weidenschilling 2003)

  4. Nearby early-type stars photo-evaporated the outer regions of the solar nebula. image
    (Hollenbach & Adams 2003; Matsuyama et al. 2003)

  5. Magneto-hydrodynamic instabilities in the outer regions of the disk prevented the formation of planetesimals in these regions image (Gammie 1996; Stone et al. 1998).

Note that many of these do not truncate nebula, but only the region where planetesimals formed.
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