I'm afraid your are in ERROR.
A nuclear blast in space in the vicinity of the asteroid DOES generate a shock wave in
the asteroid, and it doesn't require an atmosphere. You just don't understand the
When the nuclear device is detonated in the vicinity of the asteroid; it will intensely
radiate the surface of the asteroid. It is the radiative heating and blow-off of asteroid
material that WILL launch as shock wave into the asteroid.
That's how inertial confinement fusion, or laser fusion works also. The intense
radiation by the laser, and the blow-off or ablation of the fusion pellet surface, will
launch a shock wave into the fusion pellet.
Dr. Gregory Greenman