Development of technique of remote spectral sensing of technogenically loaded territories

Introduction. The article considers the problem of monitoring technologically loaded landscapes. To solve it, the authors proposed an innovative method for studying the chemical composition of objects using direct spectral sensing means. Problem Statement. The objective of this study is to consider the possibility of using spectral sensing to control the composition of soils in technogenically loaded territories. Practical Part. To confirm the hypothesis that observing changes in the parameters of reflection spectra in non-selective areas will make it possible to establish the presence of basic biogenic macroelements for plants in the soil and evaluate its fertility, or determine the degree of contamination of the territory, a laboratory experiment was conducted using modern spectral equipment and multidimensional data calibration was performed. Conclusion. The results of the analysis show the fundamental possibility of using spectral sensing in the monitoring of technogenically loaded territories using methods of multidimensional data analysis.

Мethod for orientation angles forecasting of optical instruments from the international space station with orientation platform

Onboard the International Space Station (ISS), as a part of the “Uragan” Earth exploration experiment, various observation devices are used, including photo and video spectral equipment, the orientation of which is carried out manually by the crew through the portholes. However, severe limitations are imposed on the planning of such experiments, primary related to the necessity taking into account the crew’s daily routine and the availability of time allocated for scientific experiments. The solution for expanding the ability to conduct experiments is the employing of automated orientation platforms (OP). One of these OPs is the video spectral equipment orientation system SOVA-1-426. A method for orientation angles forecasting of optical instruments for pointing at predefined objects on the Earth’s surface with SOVA-1-426 is presented. Moreover, in the described method, in addition to the coordinates of the center of mass, the current orientation of the ISS is taken into account, which makes it possible to perform the forecast with better precision. Taking into account the ISS orientation is carried out through the use of the ISS rotation quaternion to control the platform in automatic mode. The presented method for the orientation angles forecasting of high-resolution photo-camera aboard the ISS by employing SOVA-1-426 allows its automatic alignment on the Earth’s surface objects with accuracy up to seven kilometers. The described method is implemented in software and is currently used in the SOVA-1-426 OP aboard the ISS for the remote sensing of the Earth’s surface.

Procedures for in-flight calibration of satellite spectral equipment

The paper presents procedures developed for in-flight calibration of satellite spectral equipment (by solving direct and inverse problems in the theory of radiation transfer in the atmosphere) using quasi-synchronous sub-satellite point measurements. Also presented are the results of processing and analysis of several sessions of multi-level measurements conducted at the Zyabrovka test range (Republic of Belarus, Gomel region). Measurements taken from ground and air used spectral instrumentation developed at the Airspace Research department of Sevchenko IAPP of BSU to support satellite test ranges on the ground. Verification results are provided for measurements taken on the ground, in air and in space. Used for verification of the ground and space measurements were data from the multi-spectral spacecraft Sentinel-2. Key words: in-flight calibrations, sub-satellite test range, spectral brightness coefficients, field measurements.

The influence of sample preparation quality on the results of spectral analysis

Сonsiders the possibility of analyzing samples of small diameters without the use of special adapters for determining the chemical composition on spectrometers. Measurements are limited to the size of the hole on the analytical table, which is 12 mm. Accordingly, all analyzed samples must have a diameter of at least 14 mm to completely cover the sample cover of the discharge chamber in order to avoid air entering the chamber. The company manufacturer of spectral equipment offers to use special adapters for the analysis of small samples. But the use of such adapters has a number of drawbacks. These include additional cash costs for the purchase of adapters, the need for additional standardization procedures, the availability of special reference samples. In the laboratory of analytical support (LAS) of the Central Laboratory of the Factory (CLF), all samples of finished rolled products (wire rods or fittings) in size from 5.5 mm to 20 mm are prepared in the form of «blades». The compressed part of the «blade» is the analyzed surface of the sample, which is further processed on a disk grinder and transmitted to the spectral analysis. The article presents the results of comparative tests of valves class U500 between samples in the form of «blades» and in the form of «columns» and concluded that the necessity of use of special adapters.