The impacts of the pieces of Comet Shoemaker--Levy 9 should generate strong waves and fronts. Those that start out downward within a few degrees of vertical can travel large distances before reaching the surface again, and may probe to depths (13000 km) as great as the metallic-hydrogen boundary. It is shown that the wave fronts should be detectable through their stratospheric heating and cooling, by imaging in the 7.8 &mgr;m band of CH4, which is very temperature sensitive (radiance ∝T12.3). In addition to the ''seismic'' waves, the experiment should be able to detect slower-moving ducted acoustic waves near the tropopause and still slower gravity waves. ¿ American Geophysical Union 1994