During the lifetime of the Prophet ﷺ the moon was split into two parts and on that the Prophet ﷺ said, "Bear witness (to thus).  

انْشَقَّ الْقَمَرُ عَلَى عَهْدِ رَسُولِ اللَّهِ ﷺ شِقَّتَيْنِ فَقَالَ النَّبِيُّ ﷺ اشْهَدُوا  

That the Meccan people requested Messenger of Allah ﷺ to show them a miracle, and so he showed them the splitting of the moon.  

أَنَّ أَهْلَ مَكَّةَ سَأَلُوا رَسُولَ اللَّهِ ﷺ أَنْ يُرِيَهُمْ آيَةً فَأَرَاهُمُ انْشِقَاقَ الْقَمَرِ  

The moon was split into two parts during the lifetime of the Prophet.  

أَنَّ الْقَمَرَ انْشَقَّ فِي زَمَانِ النَّبِيِّ ﷺ