Northrop SM-62 Snark, c1960. The Snark’s powerful solid-rocket boosters burned for four seconds, bringing the missile’s speed up to about 300 mph, then the empty booster casings dropped away as the jet engine took over. (U.S. Air Force photo)

Northrop SM-62 Snark, c1960. The Snark’s powerful solid-rocket boosters burned for four seconds, bringing the missile’s speed up to about 300 mph, then the empty booster casings dropped away as the jet engine took over. (U.S. Air Force photo)