The secondary hazards of an earthquake generally mean a series of other hazards due, directly or indirectly, to the consequences of a strong shock, being very common and serious of earthquake hazards.

The internal flow fields in scramjet are very complex, due to the interaction of shock waves, expansion waves, boundary layer and strong reactions.

This paper shows that the interplanetary shock wave which resulting from solar events is very strong and that resulting from other disturbances is weak in general.