If they said that the moon is going to crash into earth, that would never happen. If you know anything about astronomy, you know what the roche limit is. The Roche limit, sometimes referred to as the Roche radius, is the distance within which a celestial body, held together only by its own gravity, will disintegrate due to a second celestial body's tidal forces exceeding the first body's gravitational self-attraction.[1] Inside the Roche limit, orbiting material will tend to disperse and form rings, while outside the limit, material will tend to coalesce. The term is named after Édouard Roche, the French astronomer who first calculated this theoretical limit in 1848. So all in all, this theory is crap. Should have put more effort in thinking of a way to destroy the earth.