Also, today on May 7th, 558 AD. The only 20-year-old Hagia Sophia encounters a catastrophic incident. The dome of the Holy Wisdom collapses, causing much damage within the church. The now elderly St. Justinian I the Great orders for its immediate reconstruction, but to make the dome stronger and taller.
This new dome would be the recognizable one we still see today, although not the same as the dome from this reconstruction, as it has been repaired many times before.