V. F. Fateev, S. А. Suchanov, Ju. V. Burtshev, Z. N. Khutirovsky, А. S. Samotochin
The paper in very general form describes the issues related to the risk of collision of satellites orbiting the Earth. The input of «Vympel» corporation to the search and implementation of solutions of this problem in the course of the last 20 years is described. The capabilities of the software tools developed by this corporation for the Russian Space Surveillance System are illustrated by the analysis of the real case of collision between not operational satellite «Kosmos-2251» and the operational US spacecraft «Iridium-33» that occurred on February 10, 2009.