The major challenges of space research are monitoring and exploration of our planet, which are carried out through the use of remote sensing satellites (RSS) operating in near-Earth orbits. They provide invaluable information for assessing the environmental, epidemiological and other situations on our planet, including animal migration data. The ICARUS System for Animal Tracking from the International Space Station (ISS), a joint Russian-German project on the ISS, is an ideal laboratory for in-orbit testing of instrumentation and various space technologies in order to refine methods for tracking movements of mammals and birds. The paper analyzes the experience in the operation of the animal migration monitoring system installed in the Russian segment (RS) of the ISS (ISS RS). The system has accumulated the latest accomplishments in space science, satellite navigation, control technology, and microelectronics. The scientific results on the study of animal and bird migrations obtained within the Russian research program are briefly discussed.

   The article continues studying the features of scalar calibration. The main objectives of this work are to generalize and analyze known calibration programs, compare the analytical metrics of estimates obtained from the programs generated using various target functions, assuming normal distribution of measurement errors.The article also draws conclusions about the feasibility of optimizing the calibration programs and about the general logic of their synthesis.

   Accuracy of range measurements using navigation satellites primarily depends on on-board clock correction parameters which are broadcasted to users periodically. The on-board clock offset, a critical correction parameter which accumulates due to fractional frequency offset as well as frequency drift, has to be maintained within the allocated broadcast limit throughout the satellite’s service. In IRNSS satellites, the clock offset is maintained within the broadcast limit by applying frequency offset corrections to the on-board atomic clock monitoring unit. In this paper, we discuss the methodology implemented for computing the clock offset using one-way range measurement data. Further, we report the time keeping methodology employed in IRNSS satellites that enables maintaining the satellite clock offset within the broadcast limit with minimum number of intervening frequency offset corrections throughout their operational life time.

   The paper considers a concept for designing the precision gyroscopic rate tables with digital control systems and inertial sensors as modern mechatronic control systems. Based on these systems, calibration algo-rithms for state primary standards of angular velocities can be elaborated. The designs of subordinate standards also containing inertial sensors and digital control systems can be developed based on the designs of the primary standards. These designs include the solutions earlier proposed by the authors and the new ones developed using the proposed algorithms.

   A problem of robust linear filtering of random processes is considered under given constrains on the variance of the process itself and (or) the variances of derivatives, while the form of the power spectral density of the process is assumed to be unknown. It is shown that a number of problems of navigation information processing and motion control can be reduced to the above formulation. Informativity of variances of derivatives and the effectiveness of the solutions obtained are analyzed when the variances are used to describe the properties of input processes (IP). A method for obtaining data on IP variances based on the analysis of the numerical characteristics of critical points is considered. Examples of solutions of applied problems are given.

   A procedure for measuring the systematic error in angular positioning of a rate table platform based on goniometrical method is described. The method has been tested on a three-axis rate table STA-10. Possible error sources have been detected. The positioning error has been compensated and greatly reduced. Instability of rate table axes rotation rate has been studied, and nonortogonality of its axes has been measured.