Al Mearad

Al Mearad is a historical astronomical instrument, primarily associated with Islamic astronomy, used for determining time through observation of the stars and planets. The term can refer to a range of observational tools designed for this purpose, rather than a single, standardized instrument. While specific designs varied, Al Mearad instruments generally relied on precise angular measurements to calculate the time of day or night, often relating these calculations to religious observances such as prayer times.

The term Al Mearad is derived from Arabic and broadly translates to "the measurer" or "the calibrator." This alludes to the instrument's core function: to measure celestial angles and calibrate these measurements against known celestial events.

Historically, Al Mearad instruments were important tools for astronomers, navigators, and religious scholars. They enabled accurate timekeeping, facilitated the construction of calendars, and aided in determining the qibla (the direction of Mecca) for prayer. While astrolabes and quadrants are more widely known astronomical instruments from this period, Al Mearad represents a broader category of tools dedicated to celestial measurement for temporal purposes. Distinguishing features between Al Mearad and other instruments could include specialized scales, sighting mechanisms, or intended applications.

The knowledge and use of Al Mearad instruments declined with the advent of modern timekeeping and astronomical technologies. However, the historical significance of these instruments remains important for understanding the development of astronomy and timekeeping in the Islamic world.