13.1 Introduction

Astronomy in the Islamic World in the first millenniumC.E. has left a wealth of evidence. We know of 671Arabic astronomical works from that epoch, 623 ofwhich are still preserved in manuscripts. We know356 authors of astronomical works, 91 of whom wereactive in Baghdād. These figures show that astronomywas no marginal phenomenon. The questions of howthese astronomers were trained and what methods wereused to acquire such specialized skills may seemobvious, but they have not yet been earnestlyaddressed. In this article, three groups of sourcesrepresenting three phases of educational methods,used between the 2nd/8th and4th/10th centuries, will bediscussed. In the first phase (750–800 C.E.) basiceducation was mainly achieved through memorization.This is evident from the docu- mented existence of anumber of didactic poems on astronomy. In the secondphase (800–900 C.E.) basic training was usually doneby manually performing operations with the moveableparts of a physical model of the heaven such as anastrolabe, an armillary sphere or a celestial globe.This is corroborated by a corpus of instructionaltexts by al-Khwārizmī and an early astrolabe whichwas constructed for educational purposes. In thethird phase (900–1000 C.E.) intellectual formationstarted to be organized by lectures in whichtextbooks were often used. This is documented by theemergence of commentaries on Ptolemy's Almagest and al-Farghānī'sFuṣūl. To avoidmisunderstandings though it should be em- phasizedthat these periods indicate only when these methodsstarted to be used, not when they stopped beingused.

13.2 First Phase: Memorizing Poems

In the history of astronomy we have to face the problemof a “dark century” in the Mediterranean and theMiddle East. From the middle of the1st/7th to the middle of the2nd/8th century there are notraces of any kind of activities in the field ofmathematical astronomy. Later reports on theastronomical achievements of the Arabs inpre-Islamic times have to be regarded with caution.They describe astronomical concepts which couldhardly have been Arabian in origin. In any case, thetraditional Arabic knowledge about celestialphenomena was limited to what today is called “folkastronomy”.