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تسجيل مستخدم جديدHistorical Reflections on the Work of IAU Commission 4 (Ephemerides)
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As part of a reorganization of the International Astronomical Union (IAU), Commission 4 (Ephemerides) went out of existence after the IAU General Assembly in August 2015. This paper presents brief discussions of some of the developments in fundamental astronomy that have influenced and been influenced by the work of Commission 4 over its 96-year history. The paper also presents notes about some of the publications of the national institutions that have played an essential role in the commissions mission. The contents of this paper were submitted for Commission 4s final report, to appear in IAU Transactions Vol. XXIX-A.
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It is widely accepted that stars do not form in isolation but result from the fragmentation of molecular clouds, which in turn leads to star cluster formation. Over time, clusters dissolve or are destroyed by interactions with molecular clouds or tid
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