Anthropogenic space debris pose a serious threat to operation of spacecraft (SC), including a real threat of damage and destruction of Soviet spacecraft carrying Nuclear Power Systems (NPS) onboard, which ceased their active functioning in orbit thirty years ago. Collisions of space debris with elements of SC structure may both have catastrophic consequences and cause local damage (for example, penetration of thermal control elements), resulting in the loss of spacecraft ability to function, or loss of some of their functionality. In the case of SC carrying NPS, an impact on the structure may result in debris with residual radioactivity, which calls for a continued focus on the status of this type of spacecraft in disposal orbits. In order to predict generation of space debris in near-Earth space, to evaluate SC survivability, as well as to develop engineering facilities for protection, the software package REACTOR was developed, which makes it possible to use a desktop computer to solve the problems of impact effects on complex technical objects including the function of computing the number of generated fragments (debris) and their velocity spectra. As a subject for research, a schematic SC model and a space NPS REACTOR model were constructed, calculations have been performed. As a result of calculations, qualitative and quantitative characteristics of the resulting fragments were obtained. Key words: space debris, spacecraft, collision, software package, computer, fragments, models, calculation nuclear power system.