In their content, the materials of this article represent continuation of some earlier published results of studies aimed at increasing the accuracy of determination and forecasting of the orbits of low satellites [1–7]. All these materials consider the application of the modification of the maximum likelihood technique called the technique of optimum filtering the measurements (OFM).A feature of presented materials is the determination and forecasting of parameters of the “Tchibis-M” spacecraft orbit before the reentry instant over a rather long time interval (about 10 months). This makes it possible to more fully estimate the effect of atmospheric disturbances on the calculation results and to develop recommendations on increasing the accuracy of solution of the problem in question.