Good lord, are people still really that stupid, or is this satire?
There IS NO DARK SIDE OF THE MOON (Sorry, Pink Floyd).
Any given location on the moon is iluminated by the sun for half the (Lunar) month and in the dark for the other half of the month.
What I suspect the author MEANT was that the would explode the bomb on the limb, the edge of the moons disk, as viewed from earth. If that were done at a time when the limb was in darkness, the glowing explosion would possibly be visible from Earth. Maybe. Or maybe not.
Yeah I was confused too I thought terminator moved across the surface as moon phase changes. I think limb makes more sense