Published online by Cambridge University Press: 25 May 2016
The young open star clusters (OCl) with ages of 107 − 108 years in the overwhelming majority of cases are located in the regions of a star formation which are the massive and extensive gas - star complexes (GSC) in our Galaxy. The typical sizes of GSCs are near 600 pc in projection at the Galaxy plane and the masses of such complexes are in range ∼ (105 − 107) M⊙ (Efremov (1989)). It is well known that the old open clusters avoid the regions of an active star formation in our Galaxy. As a result the structural and dynamical parameters of OCls depend on their ages and their locations relatively the nearest GSCs centres.