What was the Bell Island Boom?

Atmospheric phenomena have always fascinated me. We are still learning about strange, gigantically powerful phenomena like sprites and elfs (not elves) in the upper atmosphere. One awesome phenomenon we have confirmed is the superbolt, a long-lasting lightning bolt from the top of a thundercloud to the ground, with 100 times the power and brightness of a normal bolt. Skeptoid host Brian Dunning here details a superbolt strike, blamed on a secret superweapon by some conspiracy types, that shook Newfoundland in 1978. It destroyed appliances, killed chickens, and left holes in roofs. No wonder it had people puzzled and alarmed.