This short article was written by Professor Rudiger Lohlker in response to our invitation to summarise and bring attention to his paper “Global History: Understanding Islamic Astronomy” published in ACTA VIA SERICA, Vol. 4, No. 2, December 2019: 97–118.
When scholars reflect on the history of astronomy, they tend to restrict themselves to well-defined geographical areas. So far, scholars of science studies have not devoted sufficient attention to examining the intersections of scientific relations on a global level, especially as far as the history of astronomy is concerned.
Western or European historians tend to ignore that an important—maybe even the most important—part of the history of astronomy was written outside the confines of Eurocentric worldviews. In fact, China, South Asia, and various Islamic countries had their own traditions of astronomy.
Leaving Europe at the margins, this study will focus on premodern Islamic traditions and their relations to other traditions in China and South Asia. Taking cues from Abu-Lughod’s analysis of the non-European world system from 1250 to 1350, the history of this science therefore has to be reconceived as a global system of scientific exchange.
The main languages of cultural and scientific exchange in the period discussed here were Arabic, Chinese, and Persian. Other languages were of lesser importance. The Islamic contribution to astronomical knowledge in the period under discussion is framed through the lens of the dominant Persian contribution to Islamic knowledge production in the post-classical period of Islamic history after the twelfth century CE.
Architecture as a Space of Astronomy
Contemporary science studies has shown that laboratories, instruments, and buildings—all of them institutional aspects of the sciences—are integral to scientific knowledge production. An analysis of the history of astronomy in the Islamic world and beyond therefore best begins with a closer examination of the history of observatories.
After having established the multi-lingual heritage of Islamic astronomy, we can trace the first planned and programmed astronomic projects—built astronomy—to the reign of al-Ma‘mūn (ca. 813-833 CE). He initiated a program of astronomical observations in Baghdad, which subsequently continued in Damascus. Astronomical observations continued throughout the following centuries. The city of Marāgha in Azerbaijan was home to the most famous observatory in Islamic history, an edifice built under the patronage of the Ilkhan Hulagu (ca. 1217-1265 CE). Its director was Nāsir al-Dīn al-Tūsi (d. 1274 CE), one of the most brilliant scholars of his time: Nāsir al-Dīn al-Tūsi went down in history as a theologian, architect, philosopher, and physician. A mathematician, he was instrumental in establishing trigonometry as a discipline in its own right. In his challenge of Ptolemaic astronomy, he conceived the famous Tūsi couple.
A paragon among observatories in the new Mongol empire, Marāgha attracted scholars from near and far. Various sources mention a number of eminent Chinese astronomers and scholars working in Marāgha. It is therefore safe to assume that these scholars contributed to the famous Ilkhanate astronomical tables.
Throughout 14th and 15th century CE, scholars made great strides in producing astronomical and mathematical knowledge. The Timurid ruler Ulugh Begh (d. 1449 CE), a renowned astronomer and mathematician, founded an observatory in Samarqand. Its adjacent madrasa became a center for mathematical studies. Several directors of the Samarqand observatory also made a name for themselves for their mathematical skills.
Mathematics was a discipline fundamental to Islamic astronomy. If we want to compare the role of mathematics in Islamic astronomy to European astronomy, we should turn to Galileo Galilei’s (d. 1642 CE) work Il saggiatore, which was published in 1632 CE. In it, Galileo claims that the book of the world [nature??] only can be understood through the language of natural philosophy, i.e. mathematics. The letters of this language are triangles, circles and other geometrical figures—all of them mathematical symbols. It may be well worth reconsidering the role of mathematics in astronomy to gain new insights into astronomy, which after all is a discipline of applied mathematics. Thus, astronomy and mathematics were of importance in the Islamic world and in the early modern European world. Hence there is no priority of Europe in this respect.
The Ulugh Beg observatory inspired another observatory construction project. In the 18th century CE, the emblematic building of Jantar Mantar was created under the rule of the Hindu Rajput ruler Jai Singh II of Jaipur (1688-1743 CE). This project gave rise to an entire network of observatories. Islamic astronomy in South Asia was in turn influenced by older Indian traditions. The observatories Jai Singh II built, however, point to other influences from earlier non-Islamic Indian astronomy, which goes to show that the history of astronomy is truly an entangled one.
Throughout history, we also find other points of exchange between Islamic and non-Islamic scholars. I have already highlighted the Marāgha observatory, where Islamic and Chinese astronomers collaborated. At this location, Jamāl al-Dīn ibn Tāhir al-Bukhārī (d. around 1301 CE) may have inspired the renowned Chinese engineer, astronomer, and mathematician Guo Shoujing (d. 1316) to subsequently build the Gaocheng observatory.
Further in the West, Byzantium also stands out as a contact zone between the Islamic world and Europe. Byzantine scholars translated the works of Islamic astronomy into Greek and then transferred this knowledge to Europe. After the Ottoman conquest of Constantinople, this relation was to a certain extent reinforced when Taqī al-Dīn (d. 1585 CE), head of the new observatory in Istanbul, directly competed with Tycho Brahe (d. 1601 CE) in his scientific efforts.
These short remarks on the history of built astronomy may lead us to investigate the lives and careers of individual scholars who played a vital role in furthering astronomical knowledge. Within the scope of this article, we will content ourselves with considering the historical role of leading astronomers and mathematicians who headed the Samarqand observatory and left for Iran and the Ottoman Empire after the observatory was destroyed in the wake of political unrest.
Astronomical knowledge was also passed on through instruments. Today, many museums and collections feature astronomical instruments from the Islamic world that shaped the design of other astronomical tools around the world. Even European literature bears testament to the influence of Islamic astronomy and instruments on the European intellectual world. These instruments and their specialized use in naval and maritime contexts could inspire scholars to explore the role of astronomy in maritime handbooks—in verse and prose form—in the Islamic world and beyond. Within the scope of this study, we will not further elaborate on this subject.
Another node in the history of Islamic astronomy awaiting exploration is the history of astronomical manuscripts. I have already mentioned the collaboration between Mongol and Chinese astronomers at the Marāgha observatory. The Islamic Astronomical Bureau held a large number of books on astronomy in its collection, which were translated from Arabic and Persian. We already noted the linguistic contact with Greek Byzantium and South Asia. Buyers of books written in Oriental languages brought manuscripts on Islamic astronomy to Western Europe. A prominent example is Guillaume Postel (d. 1581 CE), a polymath, professor of Semitic languages, and translator for French diplomatic missions in the Ottoman empire. This may count as another node in the sub-network of European astronomy and serve as a proof of the European ideational debt to non-European sources.
So far, scholars have also neglected to consider the interconnections between the aesthetic agenda and intellectual concerns exhibited in manuscripts on Islamic astronomy, even though they are inextricably linked with each other. The illustrations in the lavishly illustrated Kitāb Ṣuwar al-kawākib by al-Ṣūfī (d. 986 CE) have been understood as mnemonic star maps. Scholars also created abstract mental maps of the visual ideas of the constellations, hence producing a new way of seeing and knowing.
Another way of seeing emerged through the Islamic astronomical network and its link to philosophy and theology, especially in the post-classical period, connecting astronomical ideas with the built astronomy of observatories and instruments.
The ideational framework in which Islamic astronomy evolved also highlights transformations in the interconnected fields of Islamic theology, philosophy, mysticism and even Islamic law into a post-classical configuration still awaiting exploration.
Islamic Theology and Astronomy in Post-Classical Islam
Contrary to commonly held assumptions, the above-mentioned disciplines and the sciences did not an have antagonistic relationship. We may even speak of an ongoing dialogue of Islamic religious disciplines and the sciences, which liberated the sciences and opened religious thought to new dimensions. Morrison describes this dialogue as follows: “Kalām texts associated with the Marāgha astronomers begin with the format of a philosophical text,” following along the lines of Fakhr al-Dīn al-Rāzī‘s (d. 1210 CE) al-Mulakhkhaṣ fī al-ḥikma. This dialogue continued until the fourteenth century CE. “More advanced science texts might have been produced in dialogue with kalām and would have more sophisticated arguments for the religious value of scientific theories contained within.” More scientifically-informed religious scholars continued this dialogue in the following centuries.
For the sake of the arguments proposed in this study, we have to introduce the debate of kalām and other disciplines into the history of Islamic astronomy. By using the data collected in the observatories through astronomical instruments and by including the scholar-scientists working in these contexts, we would therefore be able to integrate ideational constructions with the built astronomy showcased in observatories and astronomical manuscripts.
 A first attempt by the author is Lohlker 2019.
 Abu-Lughod 1991.
 We are not referring to ethnicized, homogenous identities, but to a world of multi-layered discourses expressed in different languages.
 Cf. Fragner 1999 with the idea of persophony and Green 2019 using persianate world.
 Cf. Latour/Woolgar 1979.
 Cf. Rheinberger 2010.
 Saliba 1987.
 Cf. Saliba 2007, 188 and Ragep 1993 on one of his major astronomical works. For his mathematical works, cf. Medzlumbeyova/Babayev 2020.
 Cf. the most interesting articles in King 1986. Cf. an excellent overview in Bergren 1997 and for the example of Ibn al-Haytham, cf. Rashed 2006.
 Galilei 1978, p. 261.
 Cf. Pingree 2003.
 Of Egyptian origin, which would allow for researching the link into North Africa.
 For more details, cf. Lohlker 2019.
 Cf. the contributions in Brown et al. 2019.
 For the case of Chaucer and his Treatise on the Astrolabe, cf. Chism 2016. The author speaks of the “multicentric pattern of astronomic knowledge transmission within” the Islamic world (p. 85) and mentions the “different archives of knowledge” created by the explorations of the use of the astrolabe around the world and the agency of this tool.
 For an overview of observatories and astronomical instruments, cf. Dizer 2001.
 For this aspect, cf. Lohlker 2019, pp.107-109.
 Translations into Latin served as a tool to introduce Islamic astronomical knowledge into the Western European world of ideas (cf. Burnett/Juste 2016).
 Cf. the articles in Damir-Geilsdorf et al. 2005.
 Cf. Berlekamp 2013.
 Cf. Dagli 2016 and Griffel 2018.
 For a first attempt, cf. Lohlker 2019 and Lohlker 2019a.
 Morrison 2014, p. 226.
 Following the argument in Morrison 2014 based on Heidrun Eichner’s position.
 Morrison 2014, p. 226.
By Rüdiger Lohlker,
Professor of Islamic Studies since 2003 at the University of Vienna (Austria).