The Production Guide for the Zarqaliyya (Universal Astrolabe) in the Work of Abu al-Hasan al-Marrakushi Atilla Bir* Saliha Bütün** Mustafa Kaçar*** Âdem Akın**** Abstract: One of the greatest astronomers of the 13th century, Abū ʿAlī al-Ḥasan al-Marrākushī is the author of Jāmiʿ al-mabādī’ wa-l-ghāyāt fī ʿilm al-mīqāt (An A to Z of Astronomical Timekeeping) which includes the production and operation guides for many astronomical instruments. Tis study translates the production guide Zarqāliyya, examines the working principle of this instrument, and presents a mathematical interpretation for current readers. A standard astrolabe provides measurements by means of disks produced separately for the diferent latitudes. Te particular disk we examine in this article was developed by the Andalusian astronomer al-Zarqālī (d. 493/1100), is named zarqāliyya, and is known as ṣafīḥa in the West. Tis disk is peculiar to Islamic astronomy and enables measurement for any latitude. At present, this astrolabe is qualifed as universal for being operational independent of latitude. Marrākushī’s discussion of this universal disk zarqāliyya in his time is an epitome for the understanding of the transmission and circulation of knowledge in the scientifc environment of Islam, and the current article evaluates this aspect. Tis article includes the subject and importance of Marrākushī’s monumental work, its modern presentations, and the mathematical explanations of the universal astrolabe’s stereographic projection. It additionally provides the formulations necessary for constructing this astrolabe and presents drawings based on these relations using the Paris edition of the manuscript registered as Or. No.2507-2508 in the National Library of France. Te stars and coptic months engraved on the instruments are presented as tables. Lastly, this study includes an annotated translation by comparing the diferent editions of the manuscript. Keywords: Marrākushī, Zarqālī, zarqāliyya, astrolabe, ʿilm al-mīqāt, ṣafīḥa, universal disk, astronomical instruments Bir, Atilla. Bütün, Saliha. Kaçar, Mustafa. Akın, Âdem. “The Production Guide for the Zarqaliyya (Universal Astrolabe) in the Work of Abu al-Hasan al-Marrakushi”, Nazariyat 6/1 (May 2020): 40-88. Atıf© dx.doi.org/10.12658/Nazariyat.6.1.M0089en DOI Received 17 January 2020 4 February 2020 Accepted Translated by Beyza Akatürk***** and Sena Aydın****** * Prof. Dr., Fatih Sultan Mehmet Vakıf University, Faculty of Literature, Department of the History of Science. Correspondence: atilabir@gmail.com. ** PhD Student, Fatih Sultan Mehmet Vakıf University, Faculty of Literature, Department of the History of Science. Correspondence: salihabudak. iu@gmail.com. *** Prof. Dr., Fatih Sultan Mehmet Vakıf University, Faculty of Literature, Department of the History of Science. Correspondence: mkacar@gmail.com. **** Assist. Prof., Fatih Sultan Mehmet Vakıf University, Faculty of Literature, Department of the History of Science. Correspondence: aakin@gmail.com. ***** Translator. ***** PhD Candidate, Istanbul Medeniyet Universtiy, Department of Philosophy. * http://orcid.org/0000 0001 7423 7690 **http://orcid.org/0000-0001-8272-8334 ***http://orcid.org/0000-0002-5867-7976 ****http://orcid.org/0000-0001-5121-8948