21 years ago, the Moon was blown out of orbit… or would have been in the fictional timeline dreamed up by Gerry Anderson, creator of “The Thunderbirds” and much other TV SF goodness in 1973.
The energetics are impossible for purely nuclear reactions, which the novelisation by E.C.Tubb freely acknowledges. In that version of the tale, Victor Bergman proposes a near total conversion reaction catalysed by the mysterious magnetic forces that cause the nuclear waste dump to explode. Perhaps it’s triggered quark matter? Of course the gee-forces invoked would’ve fragmented the Moon, but for the sake of the tale, some hand-waving is required. As the hapless Moon Base Alpha crew learn there’s intelligence Cosmic Forces involved, though never clearly identified as their voyage unfolds.