الفهرس 
الفلك والفلكيون في إيران في العصر السلجوقي،
مستخلصيوجد فقط 14 صفحة متاحة للعرض العام
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المستخلص
This study deals with astronomers and their works in Seljuk Persia. It starts with an overview on astronomy in the Islamic heritage and mentions its status in the classification of sciences, definition, fields and significance. Then the study reviews the stages of development of astronomy along the Islamic civilization, which it divides into four stages: the pre-Islamic era, the early Islamic era, the Umayyad era, and the stage of culmination at the beginning of the Abbasid era. A brief account of some of the most important astronomers is also included, as well as their works in the eastern territories under the caliphate before the establishment of the Seljuk State.
After this, the study deals with biographies of astronomers of Seljuk Persia and their volumes on astronomy. It provides a quick review of each astronomer then a detailed account of their volumes, all their manuscripts and previous studies that dealt with them. Then, the study mentions brief accounts of astronomers who left no volumes on astronomy.
Following this, the study mentions a brief account of their works, which it divides into individual works and collaborative works. The former is represented in the authorship of volumes on several branches of astronomy in Arabic and Persian, whether astronomy encyclopedias, criticism of old astronomic heritage, astronomical zijes (star catalogs), or astronomical instruments. As for the collaborative works, they include a meeting held between a number of astronomers in 467 AH, which resulted in some substantial astronomical contributions in the history of Islamic civilization.
The thesis then gives an overview of astronomy in Seljuk Persia and selects one of its topics for detailed study; namely, ”Mathematics of calendars according to al-Khazini and al-Kharqi”. At the beginning, the study provides a simple definition of each of the three calendars used back then: the Hijri Calendar, the Year of Alexander and the Yazdegerdi era, and other relevant basics. The study then highlights their efforts in this respect; namely, their attempts to know the leap year, calculation of dates, determining the beginnings of months and years, extracting dates from one another –with their three types of calendars- and determining the time of Lent for eastern christians according to the Year of Alexander.