Maragheh observatory, Iran

General description

The Maragha Observatory has a unique place in the history of medieval astronomy. It represents a new wave of scientific activities in the Islamic world in the mid 13th century, it had a key role in the development of some sophisticated pre-Copernican non-Ptolemaic systems for explaining the planetary motions, and it was the model for several observatories that were built in Persia, Transoxiana, and Asia Minor up to the 17th century. As an influential institution that was not devoted solely to astronomy, the Maragha Observatory revived advanced scientific studies during what is normally considered the period when science declined in Islam. Ideas initiating from the Maragha School impacted well beyond the Islamic territories and influenced the astronomical revolution of the 16th century

Brief inventory

The central structure, which is assumed to be the main building of the observatory, is circular. Its diameter is 22m and the base of its enclosing wall is 80 cm thick. A 1.5m-wide entrance opens into a 3.1m-wide corridor that marks the meridian line and contains the remains of the mural quadrant, of which 5.5m has survived. On each side of the central corridor are 6 rooms, the pair at each end being smaller than the rest. Outside the main building towards the south, south-east and north-east are five circular constructions. These were the places where the smaller observational instruments were once mounted. There is also a separate building, with an area of 330m², which is assumed to be the library of the observatory. In addition, archaeologists have discovered a unit where the metal parts of the instruments were cast and assembled

History

The construction of the Maragha Observatory commenced in 1259 under the patronage of Genghis Khan’s grandson Hūlāgū. Its director was Nasīr al-Dīn Tūsī (1201-1274), an eminent Persian mathematician, astronomer and philosopher whose reputation spread as far as China and whom Hūlāgū had appointed as one of his advisors. The observatory was in fact a scientific institute, with a main building for the observational equipment, some auxiliary buildings, and accommodation quarters. In the observatory, there was a library which is said to have contained about 400,000 volumes. A team of astronomers, most of whom were invited from different parts of the Islamic world, were responsible for the design and construction of the astronomical instruments, as well as for conducting observations and performing calculations.

According to a text written by Mu’ayyad al-Dīn al-‘Urdī (d. 1266), one of the chief astronomers and instrument designers of the observatory, its astronomical equipment included a mural quadrant with a radius of about 40m, a solstitial armilla, an azimuth ring, a parallactic ruler (triquetrum), and an armillary sphere with a radius of about 160cm.

After the death of Nasīr al-Dīn Tūsī in 1274, the Maragha observatory was supervised by his son and remained active until the end of the 13th century. However, following the death of Hūlāgū in 1265 and his son Abāqā in 1282, it lost its powerful patrons and had become inactive by the beginning of the 14th century. Despite this, we have reports that Ghāzān Khān, who reigned from 1295 to 1304, visited the Maragha Observatory several times, probably using it as a model for his own observatory in Tabriz (which has not survived

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