Vol 56, No 5 (2018)

This work is a continuation of paper [1], in which we discussed some incorrect approaches to the identification of large-scale types of solar wind and associated incorrect conclusions in the analysis of solar–terrestrial physics data. In this paper, we analyze the lists of 28 events of coronal mass ejection (CME) and 31 events of corotating interaction region (CIR) in 2013–2016 used by Shen et al. [2] to compare the responses of the Earth’s radiation belts to various interplanetary drivers. The interpretation of solar wind types in these lists differs both from our catalog [3] for Sheath, ICME, and CIR and from the catalog by Richardson and Cane [4] for CME. In addition, the authors of paper [2] do not distinguish the Sheath- and ICME-induced magnetic storms and include them in the general type of CME-induced storms. Our analysis has shown that, among the 28 events of CME-induced storms mentioned, 16 events belong to Sheath, 2 events to MC, 4 events to Ejecta, 2 events to CIR, and 4 events to undisturbed solar wind with shocks. The catalog [4], which also does not distinguish the Sheath and ICME, contains 18 of the 28 events presented in paper [2]. Among 31 CIR events presented by the authors of paper [2], according to our analysis, 25 events belong to CIR, 2 events to Sheath, and 4 events to undisturbed solar wind. In catalog [4], one of the 31 CIR events from paper [2] is presented as CME. Since the properties of CIR and Sheath compression regions are close, the conclusions of the authors of paper [2] on the properties of CIR-induced storms are only slightly distorted by the incorrect identification of stream types, whereas the conclusions concerning the CME-induced storms, which more than by a half represent the Sheath-induced storms, seem incorrect to us.

This paper highlights the features of modeling the process of mechanical contamination of near-Earth space (NES), gives a brief description of existing models for predicting the mechanical contamination of NES, and analyzes the influence of uncertainty in the initial data on the accuracy of predictions of the mechanical contamination of NES by modern models. It has been proposed to predict the deadline of the “ecological life” of near-Earth orbit based on a description of increasing the density of mechanical contamination in NES with logistic dependences. The analytic function has been obtained and presented for the first time, allowing one to obtain the predicted value of the deadline of the near-Earth orbit in the form of an equation that includes the value of the maximum permissible contamination density given in the form of a fuzzy value. The solution of this fuzzy equation in the case of a triangular shape of the membership function of the maximum possible contamination density has been presented. The possibility of transforming the fuzzy prediction to a crisp interval form has been shown by finding the interval crisp alpha-level set closest to the considered fuzzy set (FS).

The solar orientation mode of an artificial Earth satellite is investigated. Satellite parameters correspond to the parameters of the Bion M and Foton M-4 satellites. In this mode, the normal to the satellite solar cell plane is always directed to the Sun, the longitudinal axis lies in the plane of the orbit, and the satellite absolute angular velocity is very small. The mode is stabilized by electromagnets that interact with the Earth magnetic field and a rotating flywheel that generates a constant gyrostatic moment along the satellite longitudinal axis. Such a moment can be generated using a reaction wheel system. The constancy of the gyrostatic moment means that this system will operate without saturation. The satellite attitude control is implemented by changing the currents in the electromagnets. Two control laws that reduce the satellite angular velocity and stabilize the solar orientation are investigated. Their implementation does not require complex measurements. It is sufficient to have the readings of a solar sensor and a triaxial magnetometer and equipment for their processing. The effectiveness of control laws is confirmed by the mathematical modeling of the satellite motion with respect to the center of mass under the influence of gravitational and aerodynamic moments, as well as the moment generated by electromagnets.

The results of radiation tests of microcontrollers of the ATmega-128 type in a wide range of dose rates and temperatures have been used to estimate the probability of no-failure operation of microcontrollers in real operating conditions. The Eyring function has been used to take into account the temperature effect.