"Indeed he (Muḥammad pbuh) did see of the Greatest Signs of his Lord (Allah)." (V.53:18)

Sahih al-Bukhari · Book 65 · Hadith 4858

حَدَّثَنَا قَبِيصَةُ، حَدَّثَنَا سُفْيَانُ، عَنِ الأَعْمَشِ، عَنْ إِبْرَاهِيمَ، عَنْ عَلْقَمَةَ، عَنْ عَبْدِ اللَّهِ ـ رضى الله عنه – ‏{‏لَقَدْ رَأَى مِنْ آيَاتِ رَبِّهِ الْكُبْرَى‏}‏ قَالَ رَأَى رَفْرَفًا أَخْضَرَ قَدْ سَدَّ الأُفُقَ‏.‏

Narrated `Abdullah: (regarding the revelation) Truly he (Muhammad) did see of the signs of his Lord; the Greatest!' (53.18) The Prophet (ﷺ) saw a green screen covering the horizon.