The signs prayer (Arabic: صلاة الآيات, romanized: Ṣalāt al-ʾĀyāt) is one of the Muslim prayers that may be optional or mandatory depending on the specif conditions and the school of jurisprudence. When solar or lunar eclipses, earthquakes, thunder, or other natural phenomena (or signs, hence the name signs prayer) happen, Muslims may have to pray Ṣalāt al-ʾĀyāt. In Twelver Shia Islam, al-Ayat Prayer consists of two Rakats, and there are five Ruku in each.