By now it should be clear that the moon is staying put, but what could send it toward Earth? At minimum, you'd need an object of the same size and density as the moon to hit it at the same speed, and in the opposite direction of its orbit. This could stop the moon in its tracks, and it would fall onto Earth. Even if the collision only pushed the moon into a lower or less-circular orbit, that doesn't mean we would escape unscathed, though: If its new orbit halved its current distance from the Earth, ocean tides would get about eight times as big, Wynn-Williams says. "A lot of New Yorkers would get very wet."