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The series of celebrated and grand accomplishments and progress of mankind in space exploration make people more intelligent, quixotic, imaginative, creative and realistic. Also, these imply vision for the future, further exploration and taking advantage of the Universe, for human benefits and sustainability, gaining scientific knowledge and developing engineering structures to that end. The most modern Earth and Universe observation spacecraft to date are now equipped with large lightweight and flexible structures, such as antennas, telescopes, and extendable elements, including the incorporation of more complex and larger appendages with high precision for scientific applications. These demand more stringent structural integrity requirements to minimize performance degradation due to structural damages. In addition, spacecraft structures weight and their associated manufacturing costs should be minimized, most appropriate materials should be utilized, assembly costs should be reduced and fewer parts should be opted, or one-piece more complex configuration parts should be produced. Various sensors, actuators and control technology could be employed to reduce structural damage. Associated with these, appropriate sensors configuration and strategies for their deployment are required to accurately detect failures in the most critical areas of the structure. Spacecraft structural integrity is subject to a series of prevailing loading due to thermo-structural dynamics and environmental effects from design, manufacturing, launching and operation during their pathways to meet a multitude of objectives under a myriad of requirements and constraints. To that end, the objective of the present paper is to provide an overview on spacecraft structural integrity covering a host of selected concepts, design, methods and engineering to maintain structural integrity of space vehicles and associated sub-structures. In spite of citing examples drawn from small satellite situations under vibro-acoustic and environmental thermal loading, the overriding issues addressed could be extended to more general situations. An infographic is presented to map out the state of affairs to be addressed for structural integrity considerations. [Display omitted] The present paper is to provide an overview on spacecraft structural integrity covering a host of selected concepts, design, methods and engineering to maintain structural integrity of space vehicles and associated sub-structures, subject to a series of prevailing loading due to thermo-structural dynamics and environmental effects from design, manufacturing, launching and operation during their pathways to meet a multitude of objectives under a myriad of requirements and constraints, such as various loading and environmental effects. The Rationale and Key Technical Structural Integrity Challenge are first identified. In spite of citing examples drawn from small satellite situations under vibro-acoustic and environmental thermal loading, the overriding issues addressed could be extended to more general situations. An infographic is presented to map out the state of affairs to be addressed for structural integrity considerations. [ABSTRACT FROM AUTHOR]

Planetary protection is a guiding principle aiming to prevent microbial contamination of the solar system by spacecraft (forward contamination) and extraterrestrial contamination of the Earth (backward contamination). Bioburden reduction on spacecraft, including cruise and landing systems, is required to prevent microbial contamination from Earth during space exploration missions. Several sterilization methods are available; however, selecting appropriate methods is essential to eliminate a broad spectrum of microorganisms without damaging spacecraft components during manufacturing and assembly. Here, we compared the effects of different bioburden reduction techniques, including dry heat, UV light, isopropyl alcohol (IPA), hydrogen peroxide (H2O2), vaporized hydrogen peroxide (VHP), and oxygen and argon plasma on microorganisms with different resistance capacities. These microorganisms included Bacillus atrophaeus spores and Aspergillus niger spores, Deinococcus radiodurans, and Brevundimonas diminuta, all important microorganisms for considering planetary protection. Bacillus atrophaeus spores showed the highest resistance to dry heat but could be reliably sterilized (i.e., under detection limit) through extended time or increased temperature. Aspergillus niger spores and D. radiodurans were highly resistant to UV light. Seventy percent of IPA and 7.5% of H2O2 treatments effectively sterilized D. radiodurans and B. diminuta but showed no immediate bactericidal effect against B. atrophaeus spores. IPA immediately sterilized A. niger spores, but H2O2 did not. During VHP treatment under reduced pressure, viable B. atrophaeus spores and A. niger spores were quickly reduced by approximately two log orders. Oxygen plasma sterilized D. radiodurans but did not eliminate B. atrophaeus spores. In contrast, argon plasma sterilized B. atrophaeus but not D. radiodurans. Therefore, dry heat could be used for heat-resistant component bioburden reduction, and VHP or plasma for non-heat-resistant components in bulk bioburden reduction. Furthermore, IPA, H2O2, or UV could be used for additional surface bioburden reduction during assembly and testing. The systemic comparison of sterilization efficiencies under identical experimental conditions in this study provides basic criteria for determining which sterilization techniques should be selected during bioburden reduction for forward planetary protection. [ABSTRACT FROM AUTHOR]

Successful human space exploration requires more products than can be taken as payload. There is a need, therefore, for in-space circular manufacturing. Requirements for this include limited resource inflow, from either Earth or other planets and the generation of minimal waste. The provision of nutritious food is a clear need for human survival on the Moon or Mars and is one of the most complex to solve. Demand in large quantities, constant and reliable provision of food requires the development of specialist agricultural technologies. Here, we first review the history of space farming over the past five decades. This survey assesses the technologies which have been tested under the harsh conditions of space, identifying which modern horticultural components are applicable for in-space plant growth. We then outline which plants have been grown and under what conditions, and speculate upon the types of plants that could be selected to best nourish astronauts. Current systems are focussed on experimentation and exploration, but do not yet provide turn-key solutions for efficient food production within a long-term space exploration scenario. With that take, this review aims to provide a perspective on how an engineered closed circular environmental life-support system (ECCLES) might be constructed. To exemplify the latter, nutrient auto accumulation by biofortification is proposed through the integration of space farming and space mining, which is uncharted on Earth. • Summing up the technological improvement of space horticulture over five decades. • Reporting plants that have been grown in space, how, and the key results obtained. • Identifying potential plants and technologies for future space farming. • Introducing the engineered closed circular environmental life-support system (ECCLES). [ABSTRACT FROM AUTHOR]

The use of magnetometers for space exploration is inhibited by magnetic noise generated by spacecraft electrical systems. Mechanical booms are traditionally used to extend magnetometers away from noise sources. If a spacecraft is equipped with multiple magnetometers, signal processing algorithms can be used to compare magnetometer measurements and remove stray magnetic noise signals. We propose the use of density‐based cluster analysis to identify spacecraft noise signals and compressive sensing to separate spacecraft noise from geomagnetic field data. This method assumes no prior knowledge of the number, location, or amplitude of noise signals, but assumes that they have minimal overlapping spectral properties. We demonstrate the validity of this algorithm by separating high latitude magnetic perturbations recorded by the low‐Earth orbiting satellite, SWARM, from noise signals in simulation and in a laboratory experiment using a mock CubeSat apparatus. In the case of more noise sources than magnetometers, this problem is an instance of underdetermined blind source separation (UBSS). This work presents a UBSS signal processing algorithm to remove spacecraft noise and minimize the need for a mechanical boom. Plain Language Summary: Magnetometers are instruments designed to measure magnetic fields. They are used for a variety of purposes such as monitoring the magnetic field of the Earth from spacecraft. Spacecraft systems such as solar panels and reaction wheels generate magnetic noise that interferes with magnetometer readings. If the spacecraft has multiple magnetometers, each noise source will have a different magnitude at each magnetometer depending on the location of the noise source. The system which describes the magnitude of each noise source at each magnetometer is called a mixing matrix. We propose the use of unsupervised machine learning to estimate the mixing matrix. Once the mixing matrix is estimated, the Earth's magnetic field can be separated from spacecraft magnetic noise using a method called Compressive Sensing. Spacecraft often have many more noise sources than magnetometers, which complicates noise cancellation. The proposed method has the ability to clean noisy magnetometer measurements when there are more noise signals present than magnetometers. Key Points: We present the first use of compressive sensing with cluster analysis to separate spacecraft noise from geomagnetic field dataWe demonstrate the separation of wideband noise signals in simulation and in a lab experiment using SWARM residual geomagnetic field dataThe method enables accurate magnetic field measurements from resource limited and magnetically noisy spacecraft such as boomless CubeSats [ABSTRACT FROM AUTHOR]

Aluminum corrosion has become a major obstacle in spacecraft construction given that aluminum is used extensively throughout the construction process. Despite its many attributes in strength and durability, aluminum is susceptible to corrosion, in particular, corrosion due to microbial contamination. Scientists have encountered a number of problems with microbial aluminum corrosion within spacecraft components. Here, we summarize recent findings with regard to the phenomenon of microbiologically influenced corrosion (MIC) on space stations in the context of microbial strains isolated from the Mir space station (Mir) and the International Space Station (ISS). Given that strains found on spacecraft are of terrestrial origin, an understanding of the contribution of Al-corrosive microbes to corrosion and related risks to space travel and astronaut health is essential for implementation of prevention strategies. Accordingly, an efficient rapid identification method of microbes with the capability to degrade aluminum is proposed. In particular, onboard implementation of a matrix-assisted laser desorption/ionization–time of flight mass spectrometer (MALDI-TOF MS) is addressed. The use of a MALDI-TOF MS on board spacecraft will be crucial to future successes in space travel given that traditional methods of identifying corrosive species are far more time-consuming. Identification of microbes by way of a MALDI-TOF MS may also aid in the study of microbial corrosion and be a valuable asset for MIC prevention. [ABSTRACT FROM AUTHOR]

The article studies the current state of affairs in national space activities. The legal problems facing the space industry at the present stage, the mechanism of their solution are analyzed. The author highlights the crucial issue, which requires an immediate solution regarding the location of the launch site for domestic space objects. The special role of the State in ensuring the legal conditions for the development of national space activities, which should be carried out using good in law modern methods and means of public regulation, is determined. Nowadays, the legislation of Ukraine on space activities requires significant changes and additions, taking into account the new space realities and instruments for the development of public relations in the field of space exploration and use. The author argues that a strategy for the development of space activities in Ukraine, public administration of the space industry, as well as ensuring its restructuring require a substantial rethinking and improvement. The relevance of the legal framework for the creation and use of space defense and dual-use space technology in the interests of the national security and defense sector is underlined. The author argues that the Concept of Ukrainian law reform on space activities, including the legal rationale for choosing the optimal behavior model regarding the solution of complex legal problems based on modern space-legal doctrine and practice of space relations, should be developed. [ABSTRACT FROM AUTHOR]

This study is devoted to the features of designing the flight trajectories to the Solar System center for two promising Russian spacecraft. The scientific goal of this project is studying the circumsolar space from close distances (60–80 solar radii) and extraecliptic inclinations. The planes of the spacecraft operational orbits should be inclined in opposite directions with respect to the Sun's rotation axis. The description of the spacecraft trajectories and the main characteristics of their flight profiles are presented. [ABSTRACT FROM AUTHOR]

This article discusses the project of a space elevator based on a superconducting tether. The tether is located in a plane perpendicular to the lines of the Earth's magnetic field. Both ends of the tether are attached to the surface of the Earth forming a semicircular arch. When passing an electric current, a force arises that maintains the arch in space. This makes it possible to reduce the size and the mass of the space elevator by approximately two to three orders of magnitude. The upper point of the arch can be located at an altitude of ≈ 100 km and can be used to launch spacecraft's (or for other tasks in the study and exploration of space). Since there is no aerodynamic drag when launching a spacecraft from the space arch, the use of a gaseous propellant is considered, which can significantly increase the payload (and allows creating reusable rockets, which can return to Earth in the folded state). [ABSTRACT FROM AUTHOR]

High-Throughput Satellites (HTS) are a distinctive class of communication satellites that provide significantly more throughput per allocated bandwidth than traditional wide-beam communication satellites. They are the proverbial wave of creative disruption in the space industry and are poised to disrupt the communication market in significant ways. The objective of this work is to develop a decision-analytic framework for assessing the value of High-Throughput Satellites and to provide meaningful results of the value of such systems under realistic design, operational, and market conditions. We develop the cost and revenue models of HTS. To build the revenue model, we develop a hybrid data-driven and scenario-based load factor model that combines historical data based on financial records from current HTS operators with extrapolations based on best-, nominal-, and worst-case scenarios. We then integrate the cost and revenue models within a stochastic simulation environment and perform Monte-Carlo analysis of the net present value (NPV) of HTS. One important result is that a medium-sized HTS significantly outperforms a roughly equivalent traditional wide-beam satellite, even under the worst-case loading scenario. Another important result, here identified and quantified, is the tradeoff between the average revenue per user (ARPU) and average loading of the satellite and how it is mediated by the downlink speed provided to consumers. This result can be used in different ways, for example, by helping define the boundaries of what is competitively achievable in terms of ARPU and downlink speed offerings. The implications of these results are that they delineate the pathways to financial failure and the boundaries beyond which an HTS will be value-negative, or alternatively, the asymptotic minimum values for an HTS to be value-positive. [ABSTRACT FROM AUTHOR]

With the development and universal application of satellite technology, an important way to expand the function of satellites is setting up inter-satellite networks to make them work together. Traditional satellite networking methods generally adopt a fixed time slot allocation method, which is not suitable for small satellite groups with low latency and high throughput requirements. In order to solve this problem, it has been proposed to apply the traditional Wifi protocol in satellite networking. As there are differences between satellite networks and terrestrial networks, it’s necessary to improve the traditional 802.11 protocol. The Media Access Control (MAC) protocol in 802.11 is improved in this paper, which mainly includes the adaptive algorithm of maximum contention window size and the growth algorithm of Contention Window (CW) size. The maximum contention window is adjusted according to the conflict state of the current network, which makes the network accommodate more satellite nodes. The CW growth algorithm improves the traditional Binary Exponential Back-off (BEB) algorithm, where the CW is designed according to the priority of the data frame or the network load. In this way, high-priority satellite accusation information will have higher reliability or tolerate greater network load. [ABSTRACT FROM AUTHOR]

To ensure that scientific investments in space exploration are not compromised by terrestrial contamination of celestial bodies, special care needs to be taken to preserve planetary conditions for future astrobiological exploration. Significant effort has been made and is being taken to address planetary protection in the context of inner Solar System exploration. In particular for missions to Mars, detailed internationally accepted guidelines have been established. For missions to the icy moons in the outer Solar System, Europa and Enceladus, the planetary protection requirements are so far based on a probabilistic approach and a conservative estimate of poorly known parameters. One objective of the European Commission-funded project, Planetary Protection of Outer Solar System, was to assess the existing planetary protection approach, to identify inherent knowledge gaps, and to recommend scientific investigations necessary to update the requirements for missions to the icy moons. [ABSTRACT FROM AUTHOR]

In this article, a new method of spacecraft travelling in outer space is considered. It consists in using the magnetic field and the gravitational field of the celestial bodies of the Solar System, with the help of a new engine (consisting of a superconducting magnet and an electric jet propulsor). The superconducting magnet is made as sealed toroidal hollow balloon whose surface is covered with a thin layer of superconductor. When the spacecraft moves near a celestial body, the flux of the magnetic field changes and it leads to the appearance of an electromotive force. As a result, a superconducting magnet produces an electric current, which is used to operate an electric jet propulsor. It is shown that the thrust force of the electric jet propulsor can exceed the braking force (which acts on a superconducting magnet), and the spacecraft increases the flight velocity. The proposed engine is appropriate to be used when exercising Oberth maneuver when a spacecraft falls into a gravitational well and its velocity fall reaches a maximum value. The obtained results show that the creation of new engines can be a promising direction in the development of space technology. [ABSTRACT FROM AUTHOR]

The present study examines the problem of moral values arising aboard manned spacecrafts. The authors believe that this problem is due to the transition of modern society to the Information Age. Under the conditions of a space flight, when the vital functions of the crew and passengers of a spacecraft are provided and controlled by information and communication technology, the problem of moral values takes on special significance. Information technology, as well as their applications can be divided into three types. These are technologies that record (store), transmit (communicate) and organize information. The authors studied the features of the influence of each type of information and communication technology on moral values and artistic freedom in the microsocial group of a spacecraft. Solving the problem of moral values aboard a manned spacecraft is a sine qua non for artistic freedom during a space flight, the quality of the tasks associated with the colonization of the outer space and the development of material, energy and information resources of the universe. [ABSTRACT FROM AUTHOR]

EFs are a set of processes that supports many cognitive domains as goal setting, monitoring, planning, and cognitive-behavioural flexible control. Currently, many standardized paper-and-pencil tests or scales are used to assess EFs. These tests are easy to administer, score, and interpret but present some limitations in terms of generalizability of behaviours in real life. More recently, Information and Communication Technology has provided a higher ecological validity in the EFs assessment. In order to increase the ecological validity, we have developed a serious game (SG), named EXPANSE, which aim was to compare the participants’ game performance (latency times, and correct answers) with the results obtained in the traditional tasks and scales. 354 healthy subjects participated to the study and the findings showed significant correlations among standard tasks and the serious game. The exploratory nature of the present study, on one hand, highlighted that SG could be an additional behavioral tool to assess EFs and, on the other, we need further investigations, including clinical populations, for better defining the game sensitivity toward EF components. Finally, the results show that serious games are a promising technology for the evaluation of real cognitive behavior along with traditional evaluation. [ABSTRACT FROM AUTHOR]

A new sequential method based on multi-resolution approximation is proposed for solving computationally expensive multi-objective optimization problems. A traditional strategy is to decompose a multi-objective optimization problem into a number of single-objective optimization problems, whereby the PF can be regarded as a function of weights. Therefore, it is very natural to use wavelet multi-resolution approximation techniques for setting weight vectors. In our framework, the sequential approach starts with sampling aggressive functions on the initial coarsest grid with a few collocation points; once a rough PF is obtained, new points are automatically added on the basis of an adaptive wavelet collocation method. Therefore, the PF can be approximated with a relatively small number of weights. The efficiency of our method is demonstrated on two examples: a typical multi-objective optimization problem and an expensive multi-objective control optimal problem. [ABSTRACT FROM AUTHOR]

Spacecrafts need to maneuver their solar panels towards the sun and antennas towards the ground station for maximum solar power harvesting and communication with the ground station. For tracking purpose, usually magnetorquer rods, reaction wheels and permanent magnets are used, but they are heavier, expensive, and occupy extra space on the spacecraft. Keeping in mind the dimension, budget and mass constraints of small satellites, a system compatible with small satellite is worth consideration. Consequently, this paper focuses on designing and analyzing a solar panel module with embedded Air-Coil. Such an Air-Coil is an innovative idea for the replacement of heavier, bulky and expensive attitude control systems. The proposed Air-Coil is integrated in the internal layers of an eight layers solar panel PCB module. Complete degradation analyses of the solar panel have been done to ensure that it will meet the satellite power requirements at BOL (beginning of life) and EOL (end of life). The proposed embedded Air-Coil has been analyzed for the generated magnetic moment, resultant torque, power consumption and temperature increase of the complete solar panel unit. A steady state thermal model is proposed to measure the thermal resistance between top and bottom layers of the solar panel module, which gives an idea about the heat trapped inside the solar panel module. The designed embedded Air-Coil is fully reconfigurable where coil in each layer can be operated as a separate coil. The four coils in different layers can be attached or detached through switches in different configurations i.e. single coil, four in series, four in parallel, and their hybrid combinations. The analyses of power consumption, heat dissipation, temperature rise, magnetic moment and torque generation by different configurations of the designed Air-Coil have been performed. The generated magnetic moment is very high i.e. around 12Am2, which is enough to rotate a microsatellite by 90° in 200s. The efficacy of the proposed module is significantly higher than the already available systems with respect to mass, price, power dissipation, heat generation, and dimension. [ABSTRACT FROM AUTHOR]