Exploring The Astrolabe

Does Anybody Know What Time It Is?

Exploring The Astrolabe

The history of time measurement has marked the upward surge of mankind, and technology. We know about modern wristwatches, and we know about pocket watches, but how did humans measure time before the pocket watch? They used a curiously magnificent device named the Astrolabe. Kuristas.com has a superb article on the history of the Astrolabe, which I highly recommend reading.

Evan Bench took the stunning images above and below of the Astrolabe and said:

An 18th century Astrolabe. This is copy made in the late 18th century of a popular astrolabe originally designed in the early 18th century. I found this in a souk in Marrakech.

An astrolabe is a historical astronomical instrument used by classical astronomers, navigators, and astrologers. Its many uses included locating and predicting the positions of the Sun, Moon, planets and stars; determining local time given local latitude and vice-versa; surveying; and triangulation.

In the medieval Islamic world, they were used primarily for astronomical studies, as well as in other areas as diverse as astrology, navigation, surveying, timekeeping, Salah prayers, and Qibla. Astrologers of the European nations used astrolabes to construct horoscopes.

This particular astrolabe was made to order as a decorative item sometime in the late 18th century. As the markings are not precise, it would be difficult - if not impossible - to accurately determine astrological events using this piece. The plates themselves are well-scribed and could be used to determine approximate latitude.

The various parts of an 18th century astrolabe as seen above were made in North Africa.

Astrolabes are a historical astronomical instrument used by classical astronomers, navigators, and astrologers. Its many uses included locating and predicting the positions of the Sun, Moon, planets and stars; determining local time given local latitude and vice-versa; surveying; and triangulation.

In the medieval Islamic world, they were used primarily for astronomical studies, as well as in other areas as diverse as astrology, navigation, surveying, timekeeping, Salah prayers, and Qibla. Astrologers of the European nations used astrolabes to construct horoscopes.

The first astrolabes were made in the 3rd century but advanced brass astrolabes did not appear till the middle ages (8th and 9th century).

The plates of this instrument are made of brass but are unusual in that they have been electroplated in gold. The thin layer of gold has been worn off over the years.

This instrument is a copy of a much older instrument used in the 17th century. Astrolabes were often copied and given as gifts. This one is a low quality copy found in a souk in Marrakech. It was probably made in the 18th century. The accuracy of the markings is poor and so it would be difficult to actually use this instrument to make calculations.

Think of it as 18th century "bling": In the 16th and 17th centuries, the possession of an astrolabe lent an element of prestige and intelligence to the owner.

Now it's just a hunk of brass that no one knows how to use. The mathematical principles behind its use are fairly complex. Basically it's a mechanical device for predicting the movement of celestial bodies (usually the moon, sun, planets, and principal stars). It was used in the Arab world in may ways. For one, to determine the times of sunset and sunrise as well as lunar cycles. It could also be used for navigation to determine ones approxiamate longitude and latitude. The North African Moors brought the astrolabe to Europe and it was quickly made popular for navigation and celestial mechanics.

As an instrument of astrology it was used extensively by Sufis (Islamic mystics; especially in the Persian world) to create astrological maps based on events. This small one is not as astrological astrolabe but rather an astronomical one. Astrological astrolabes have detailed astrological charts and maps on the inside and back of the mater. This one has mathematical tables instead.

Many astrological astrolabes are Persian (Iran) in origin.