After the (*) conquest of Constantinople, which had this object on its crest, it was adopted as an Islamic symbol.
This thing names a sura whose verses describe the Day of Judgment and tell the stories of 'Ad and Thamud to explain consequences of not heeding God, and which is named for a miracle in which this thing is split open. Some Christians claim that Allah is a pagan Arabian god of this, just like Hubal. After the (*) conquest of Constantinople, which had this object on its crest, it was adopted as an Islamic symbol. The Islamic calendar is based on this object's cycles. Islam is often symbolized by - for 10 points - a "crescent" representing what object?
This thing names a sura whose verses describe the Day of Judgment and tell the stories of 'Ad and Thamud to explain consequences of not heeding God, and which is named for a miracle in which this thing is split open.
The Moon [or al-Qamar; accept crescent moon; prompt on crescent with "crescent what?"]