Giant planet growth and migration instigates high velocity collisions between planetesimals. Collisional disruption temporarily enhances the dust to gas ratio in the excited regions. The period of chondrule formation ends abruptly by dynamical clearing of small bodies near the giant planets.

Some vaporizing collisions generate nebular shocks strong enough to melt free-floating debris. The gas density limits the size of entrained particles. Vapor plume expansion creates a pressure low that reverses the flow direction, collapsing and mixing materials with different thermal histories.

Vaporizing collisions create distinct local environments in the nebula with characteristics consistent with many observations from chondritic meteorites. Giant planet migration can explain the timing and locations of chondrule formation. This chondrule model can also explain major differences between the main chondrite classes.