Islamic astrolabe (shown in parts)

A vital tool

Knowing the time for prayer and locating the direction of the holy city of Mecca is a key part of Islam. Medieval Islamic scholars developed the original Ancient Greek design for an astrolabe to create a highly sophisticated instrument. Many 11th-century mosques employed their own muwaqqit or astronomer-timekeeper who was responsible for using an astrolabe like this one to determine the essential prayer times and directions.