The front displays a picture of the astrolabe, an early scientific instrument developed by the Greeks, but improved by medieval Arab astronomers. The instrument is able to measure the time of day or night, along with altitude and latitude, and helped the Arabs to determine the time to fast during Ramadan.
The back displays the Sprial Minaret of Samarra dating back to 848 CE, when Samarra was the capital of the Abbasid Empire.