KEY WORDS AND IDEAS
Astronomy, technology, Renaissance, Iran, cultural exchange, calligraphy (nasta'liq script), brass, steel
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Astrolabes were the most important astronomical instruments in the Islamic world and Europe until the early Renaissance. Astrolabes created in the Islamic world made their way to the West and shaped the production of these scientific tools in Europe.
An astrolabe maps the spherical universe on a flat surface without compromising the exact angles between the celestial bodies. Thus, it can show the position of the stars and planets in the sky at a particular location and time. When given certain initial values, astrolabes can do a range of astronomical, astrological, and topographical calculations, such as measuring latitudes, telling time, and determining hours of daylight. They were also used to determine prayer times and the direction of Mecca.
An astrolabe consists of a number of stacked circular plates, which rotate around the axis of a central pin (fig. 19). The topmost plate, the rete, was often decorated. In this example, an elegant cut-brass lattice forms the bismillah, the opening phrase of most chapters (suras) of the Qur'an. The degrees of latitude and geographical locations are engraved on the topmost plate. The name of the maker is on the back.
The earliest examples of Persian astrolabes date from the ninth and tenth centuries. This particular one was made in seventeenth-century Iran, a flourishing center of astrolabe production. Scientists and artisans in the Islamic world embellished and refined the astrolabe, which was originally an ancient Greek invention. Astrolabes produced in the Islamic world inspired those made in Europe. For example, this astrolabe and another by a Flemish maker, Arsenius, with a similar calligraphic design, were both based upon earlier Islamic prototypes.
RELATED AUDIO FROM THE GALLERY GUIDE
Navina Haidar: We're looking at the metal object that's shaped mostly like a circle with a pointed arch shape and a loop at the top. On the front of it is a dial with very complicated markings. Do you see all the thin, dark markings, even around the edge? This is a scientific instrument for studying stars and planets, but it's decorated as an object of art, as well. It's called an astrolabe. To use it, you'd hold the astrolabe up with the thumb of one hand with the loop at the top and look through a tube on the back of it, gazing at a particular star. Then you'd move the dials on the front to figure out the location of other stars and planets on that day.
Astrolabes were really important tools for medieval astronomers. Astronomy was an advanced science in the Islamic world in general. In the Islamic world, astrolabes also helped people figure out the correct times and direction to face for their daily prayers.