Save the Planet, Feed the Star: How Super-Earths Survive Migration and Drive Disk Accretion

Understand

Two longstanding problems in planet formation include (1) understanding how planets survive migration, and (2) articulating the process by which protoplanetary disks disperse---and in particular how they accrete onto their central stars.

• We can go a long way toward solving both problems if the disk gas surrounding planets has no intrinsic diffusivity ("viscosity").
• In inviscid, laminar disks, a planet readily repels gas away from its orbit.
• On short timescales, zero viscosity gas accumulates inside a planet's orbit to slow Type I migration by orders of magnitude.