Survey and analyzing astronomical concepts as the shape and decorative images in metal works of the Seljuk period (Case Study: Brass catchment)

Astronomy and astronomical instruments during the Islamic era due to various needs and requirements in Muslims life، such as awareness of time، sunrise and sunset for praying and issues of navigation and geographic matters and astrology phenomenon، and crossed the Sad days، nights and different times، became one of the most important scientific phenomena. Iranian metal worker artists of those days which were a part of the body of that society were aware of the importance and role of astronomy and astronomical matters and tried to reflect astronomical concepts and themes as decorations، as well as the production of a variety of astronomical astrolabe (the flat، spherical) and sundial، on metal works. The purpose of this paper is follow the contents of different kinds of decorations in Seljuk metal works especially in Herat school، besides introducing and proving the importance of place of astronomy and astronomical instruments especially by surveying on astronomical concepts like astronomical constellations، the twelve Zodiac tower and astrolabe and its components as a product of astronomical instruments on brass catchments made in Herat at Seljuk period. The question posed in this study is whether the astronomy and astronomical concepts has been used as decoration on the surfaces of metal works in Seljuk period? This article is a descriptive – analytical study and its data collections have been done by library and field (search the museum) researches.