The blast and fallout of a nuclear device, the only known manmade weapon capable of creating such damage, upon our moon would cause massive amounts of Gamma Radiation to spread farther and faster, ionize our atmosphere, filling it with electricity, and expose cancer causing radiation world wide, and cause massive blackouts spanning continents. It would also destroy the moon, and without it’s gravitational effect on the Earth, the tides would immediately rise in a massive wave, and towards the direction of the only thing that still effects tides, the Sun, destroying everything in it’s path, and without the moon, the Earth’s axis would wobbles to an axial tilt from 23 degrees to over 87 degrees, causing extreme climate change humans or any other life are not accustomed to.