Realistically, the impact of such an unlikely accident will be no worse than the results of any atmospheric nuclear bomb test, mentioned earlier, which entailed the detonation of multimegaton
nuclear weapons that produced large amounts of radioactive debris in the form of fallout.
Two other well-known and well-studied events are the June 30, 1908, multimegaton
Tunguska blast (S&T: June 1994, page 38) and the February 12, 1947, Sikhote-Alin impact (S&T: February 1997, page 50).
The first American missile defense interceptor, the Nike-Zeus, was a large, ground-controlled projectile that carried a multimegaton