What is the meaning of the verse, "The Hour has approached, and the moon has split"?

"The Hour has drawn near" means the time for the establishment of the Hour is close, because what remains of this world after the Prophet's (peace be upon him) mission is little compared to what has passed. As for "the moon was cleft asunder," it means it split, and this indeed occurred during the time of the Prophet (peace be upon him). The consecutively transmitted (mutawatir) hadiths have affirmed its occurrence.