Lunar cycle

This Arabic manuscript was compiled at a time when there existed two separate disciplines of ‘The Positions of the Stars’ and of ‘Stellar Judgments’. The Kitāb al-Bulhān (Book of Wonders) tracks the astronomical movements of the planets, which are then interpreted as astrological predictors of the future, as well as a means of understanding the present. The diagram shows how the moon waxes and wanes during each cycle of the lunar phases, which lasts approximately 29.5 days.

Iṣfāhānī, ʻAbd al-Ḥasan ibn Aḥmad ibn ʻAlī ibn al-Ḥasan, Kitāb al-Bulhān (Baghdad, c. 1400-1450)