Originally Posted by **********

Taylor (Heston) is an Astronaut, he would have immediately recognized the moon and knew he was on Earth, much earlier in the movie instead of finding out at the end. But since the Statue of liberty is found half buried in sand, the destruction of the moon could have changed the tides or caused geological changes, letting the statue be found on the beach.

The moon's destruction is never directly mentioned, but it's hinted. One of the astronauts says "There was always a strange cloud cover at night". I assumed at first it was H-bomb dust of some kind but it could also mean moon dust in the atmosphere, or as a ring around the planet.