Solar System Research

In this paper, we calculate the equivalent flux and nonionization dose of neutrons emitted by plutonium dioxide-based radioisotope thermal blocks (TBs) mounted as assemblies on the landing module (LM) of the spacecraft (SC) Exomars-2020. These parameters characterize the nonionization interaction of neutrons with materials of modern integrated circuits (ICs), the so-called displacement effects or structural damage. As an example, an assessment was performed for Russian devices installed on the LM at minimal distances from the TB assemblies. The results are compared with typical values ​​of IC resistance to structural damage. The sizes of the characteristic areas of the device location on the LM, where displacement effects in the IC components cannot be neglected, and moreover, can cause device failure, are also determined.

The paper focuses on a future mission to Venus, Venera-D, which is presently at the stage of defining the scientific objectives and shaping the preliminary mission architecture. The main scientific goals regarding the atmosphere, magnetosphere and internal structure of Venus are considered. The current configuration, baseline, and additional elements of the mission are described.

Spektr-UF is a multipurpose space observatory equipped with a telescope with a primary mirror 170 cm in diameter. The main task of the observatory is obtaining high-resolution spectra of cosmic objects and images of diffraction quality in the UV region (115–310 nm). For the solution of the second task, the Field Camera Unit (FCU) is intended. The design of the FCU changed in the course of work on the project. In this paper, we describe the current version of the FCU and the main scientific tasks to be accomplished with the instrument. Its characteristics are compared to those of the cameras of the Hubble Space Telescope.

The schemes of unburied thermal probes and the principles of their operation are considered. The efficiency of each scheme is evaluated.

An approximate assessment of the electrical fields generated on charging the spacecraft is performed. The interference generated by the protecting device intended for neutralizing a noncompensated electrical charge on the spacecraft body is assessed. The assessment shows that the electrical fields can lead to failures in operations of the onboard electronic equipment.

This paper presents the project of the space astrophysical observatory Astron-2 aimed to carry out the all-sky spectral and photometric survey in the ultraviolet spectral region (115–310 nm). The major instrument of the observatory is a 210-cm aperture telescope with a field of view of approximately 2 degrees. Six additional telescopes with an aperture of 30–40 cm and a field of view of 10 degrees will be used for the all-sky survey in a wide range of wavelengths simultaneously with ultraviolet observations. The expected timeframe for the construction of the Astron-2 observatory is 2025–2035 with the launch after the completion of the Spektr-UF mission. The list of the most important astrophysical problems that can be solved with Astron-2 is presented. Taking into account the facilities created during the implementation of the Spektr-UF mission, the total cost of Astron-2 will be much less than the NASA and ESA next generation missions. At the same time, this project will become a flagship mission in astrophysics, which will allow Russia to have a “scientific monopoly” in UV observations.

The article discusses the possibility of determining surface elevation using a conventional spaceborne synthetic aperture radar (SAR) survey by one satellite without interferometric phase measurements of the slant range. The capabilities of such determination are examined. A schematic diagram is given. Advantages and disadvantages are analyzed.

This article describes an experimental facility, which simulates the natural operating conditions of radiative coolers used for cooling photo-detectors of electronic optical equipment of spacecraft. The composition and main properties of the facility and the specific features of thermal vacuum tests at cryogenic temperatures are considered. Results of thermal vacuum tests of the radiative cooler for MSY-GS device used onboard a meteorological spacecraft are provided. The results are in good agreement with in-flight data.

In this paper we describe scientific problems of stellar astrophysics that require observational data in the ultraviolet domain of the electromagnetic spectrum. These problems will be included in the scientific research program of the Spektr-UF international space mission.

The article considers the problem of controlling the relative motion of spacecraft (SC) flying in tandem for interferometric imaging. The effect of the geometry of the tandem configuration on the value of the effective baseline in constructing a digital elevation model is analyzed taking into account the availability of certain geographic latitudes of the Earth’s surface for radar surveys. Restrictions on the location of operating intervals of the active SC with a transmitting antenna are considered to exclude the possible irradiation of another SC in tandem. The problems of orbit correction for changing the geometry of the tandem configuration are considered. Energy costs are estimated.

The resolution of ambiguity of references in the phase multirange rangefinder is considered as a way to determine the correct cycle of the full phase corresponding to the measured phase. All successive cycles of the full phase are interpreted as a system of discrete signals, and the desired one is determined by the geometric pattern of reception of such signals according to Kotel’nikov’s theory of potential noise immunity.