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Biodegradation of materials on crewed spacecraft can cause disruption, loss of function and lost crew time. Cleaning of surfaces is only partially effective due in accessibility and resource concerns. Commonly affected surfaces are hand-touch sites, waste disposal systems and liquid-handling systems, including condensing heat exchangers. The use of materials on and within such affected systems that reduce the attachment of and degradation by microbes, is an innovative solution to this problem. This review aims to examine both terrestrial and space-based experiments that have aimed to reduce microbial growth which are applicable to the unique conditions of crewed spacecraft. Traditional antimicrobial surfaces such as copper and silver, as well as nanoparticles, long-chain organic molecules and surface topographical features, as well as novel “smart” technologies are discussed. Future missions to cis-lunar and Martian destinations will depend on materials that retain their function and reliability for their success; thus, the use of antimicrobial and antifouling materials is a pivotal one.

A study was made of the time parameters of the cyclogram for maintaining the low working orbit of a small spacecraft of the AIST-2 class using an electric jet engine. The analysis is made for working orbits with a height in the range from four hundred to five hundred kilometers with a changing upper atmosphere of the Earth, depending on the level of solar activity. The calculations used the thrust of an electric jet engine equal to twenty millinewtons with a service life of not more than a thousand hours. The methodological and software were used: for calculating the level of aerodynamic drag depending on the level of solar activity; for modeling and analysis of the parameters of the orbital motion of the spacecraft under the action of corrective and aerodynamic forces. The results of the analysis showed that the electric jet engine allows maintaining the working orbit in the range of designated heights. If the average altitude of the orbit deviates by no more than three kilometers, correction can be carried out in less than a day. The time of one correction cycle can vary from four to four hundred and seventy-eight days, depending on the level of solar activity and the design and ballistic parameters of the spacecraft. The operating life of an electric jet engine equal to one thousand hours can maintain the working orbit of the spacecraft for more than seven years with low solar activity in the range of the studied heights.

Digital multipliers are key component of all digital signal processing applications. Numerous algorithms and architectures have been proposed to design high-speed and self repairable multipliers for critical applications like space craft and medical applications. This work proposes a self checking scheme for fixed-width array multipliers. The proposed scheme verifies multiply operation by single digit conversion based verification, mainly relying on the use of addition called (MVA) multiplication verification algorithm. To tolerate the fault that occurs in the multiplier circuit, redundancy replicas of multiplier modules are used to replace faulty one. Our proposed multiplier has been implemented using synopsis complier tool, which achieve a low-cost fault-tolerant design when compare with conventional redundancy based error tolerant techniques.

Meta-heuristics has a long tradition in computer science. During the past few years, different types of meta-heuristics, specially evolutionary algorithms got noticeable attention in dealing with real-world optimization problems. Recent advances in this field along with rapid development of high processing computers, make it possible to tackle various engineering optimization problems with relative ease, omitting the barrier of unknown global optimal solutions due to the complexity of the problems. Following this rapid advancements, scientific communities shifted their attention towards the development of novel algorithms and techniques to satisfy their need in optimization. Among different research areas, astrodynamics and space engineering witnessed many trends in evolutionary algorithms for various types of problems. By having a look at the amount of publications regarding the development of meta-heuristics in aerospace sciences, it can be seen that a high amount of efforts are dedicated to develop novel stochastic techniques and more specifically, innovative evolutionary algorithms on a variety of subjects. In the past decade, one of the challenging problems in space engineering, which is tackled mainly by novel evolutionary algorithms by the researchers in the aerospace community is spacecraft trajectory optimization. Spacecraft trajectory optimization problem can be simply described as the discovery of a space trajectory for satellites and space vehicles that satisfies some criteria. While a space vehicle travels in space to reach a destination, either around the Earth or any other celestial body, it is crucial to maintain or change its flight path precisely to reach the desired final destination. Such travels between space orbits, called orbital maneuvers, need to be accomplished, while minimizing some objectives such as fuel consumption or the transfer time. In the engineering point of view, spacecraft trajectory optimization can be described as a black-box optimization problem, which can be constrained or unconstrained, depending on the formulation of the problem. In order to clarify the main motivation of the research in this thesis, first, it is necessary to discuss the status of the current trends in the development of evolutionary algorithms and tackling spacecraft trajectory optimization problems. Over the past decade, numerous research are dedicated to these subjects, mainly from two groups of scientific communities. The first group is the space engineering community. Having an overall look into the publications confirms that the focus in the developed methods in this group is mainly regarding the mathematical modeling and numerical approaches in dealing with spacecraft trajectory optimization problems. The majority of the strategies interact with mixed concepts of semi-analytical methods, discretization, interpolation and approximation techniques. When it comes to optimization, usually traditional algorithms are utilized and less attention is paid to the algorithm development. In some cases, researchers tried to tune the algorithms and make them more efficient. However, their efforts are mainly based on try-and-error and repetitions rather than analyzing the landscape of the optimization problem. The second group is the computer science community. Unlike the first group, the majority of the efforts in the research from this group has been dedicated to algorithm development, rather than developing novel techniques and approaches in trajectory optimization such as interpolation and approximation techniques. Research in this group generally ends in very efficient and robust optimization algorithms with high performance. However, they failed to put their algorithms in challenge with complex real-world optimization problems, with novel ideas as their model and approach. Instead, usually the standard optimization benchmark problems are selected to verify the algorithm performance. In particular, when it comes to solve a spacecraft trajectory optimization problem, this group mainly treats the problem as a black-box with not much concentration on the mathematical model or the approximation techniques. Taking into account the two aforementioned research perspectives, it can be seen that there is a missing link between these two schemes in dealing with spacecraft trajectory optimization problems. On one hand, we can see noticeable advances in mathematical models and approximation techniques on this subject, but with no efforts on the optimization algorithms. On the other hand, we have newly developed evolutionary algorithms for black-box optimization problems, which do not take advantage of novel approaches to increase the efficiency of the optimization process. In other words, there seems to be a missing connection between the characteristics of the problem in spacecraft trajectory optimization, which controls the shape of the solution domain, and the algorithm components, which controls the efficiency of the optimization process. This missing connection motivated us in developing efficient meta-heuristics for solving spacecraft trajectory optimization problems. By having the knowledge about the type of space mission, the features of the orbital maneuver, the mathematical modeling of the system dynamics, and the features of the employed approximation techniques, it is possible to adapt the performance of the algorithms. Knowing these features of the spacecraft trajectory optimization problem, the shape of the solution domain can be realized. In other words, it is possible to see how sensitive the problem is relative to each of its feature. This information can be used to develop efficient optimization algorithms with adaptive mechanisms, which take advantage of the features of the problem to conduct the optimization process toward better solutions. Such flexible adaptiveness, makes the algorithm robust to any changes of the space mission features. Therefore, within the perspective of space system design, the developed algorithms will be useful tools for obtaining optimal or near-optimal transfer trajectories within the conceptual and preliminary design of a spacecraft for a space mission. Having this motivation, the main goal in this research was the development of efficient meta-heuristics for spacecraft trajectory optimization. Regarding the type of the problem, we focused on space rendezvous problems, which covers the majority of orbital maneuvers, including long-range and short-range space rendezvous. Also, regarding the meta-heuristics, we concentrated mainly on evolutionary algorithms based on probabilistic modeling and hybridization. Following the research, two algorithms have been developed. First, a hybrid self adaptive evolutionary algorithm has been developed for multi-impulse long-range space rendezvous problems. The algorithm is a hybrid method, combined with auto-tuning techniques and an individual refinement procedure based on probabilistic distribution. Then, for the short-range space rendezvous trajectory optimization problems, an estimation of distribution algorithm with feasibility conserving mechanisms for constrained continuous optimization is developed. The proposed mechanisms implement seeding, learning and mapping methods within the optimization process. They include mixtures of probabilistic models, outlier detection algorithms and some heuristic techniques within the mapping process. Parallel to the development of algorithms, a simulation software is also developed as a complementary application. This tool is designed for visualization of the obtained results from the experiments in this research. It has been used mainly to obtain high-quality illustrations while simulating the trajectory of the spacecraft within the orbital maneuvers., La Caixa TIN2016-78365R PID2019-1064536A-I00 Basque Government consolidated groups 2019-2021 IT1244-19

Cinesite created many effects in the Tony Stark Lost in Space sequence as well as recreating environments from previous Marvel films, including Camp Lehigh ("First Avenger") and Morag ("Guardians of the Galaxy"). Other CG includes the Outriders chasing Hawkeye, space craft, Nebula's cybernetic arm, and a fully CG war machine.

Space microbiology pays attention toward possible microbial interactions in outer space or in distant shell of earth. Environmental conditions of outermost shell and space craft and their effect on microbiome need to be explored for basic understanding and for possible applied aspects. Various exposure facilities are developed for such studies. This chapter provides an overview about main aspects of space microbiologist, locations for research, their environment conditions, sample processing tools, and future aspects of space microbiology.

The penultimate period that we will tackle is the Space Age. For me, born in 1967, this still looms large as an age of exciting, grand achievements: landing humans on the Moon; the Space Shuttle; and space craft sent to the outer reaches of the solar system.

2Without the products of mining there would be no civilization as we know it, so a world without mining is unlikely, at least for the foreseeable future. There is, however, a paradox: whereas we enjoy the end products of mining, from simple tools and jewelry to advanced space craft, we are less fond of the ‘holes in the ground’ needed for their supply or the wastes that accompany most mining operations. A disconnect between source and product is even reflected in the structure of the metals industry with some manufacturing companies keen to deny their connection to mining on the basis that much of their raw materials come from secondary sources.

The electric and magnetic field instrument suite FIELDS on board the NASA Parker Solar Probe and the radio and plasma waves instrument RPWS on the ESA Solar Orbiter mission that explore the inner heliosphere are sensitive to signals generated by dust impacts. Dust impacts were observed using electric field antennas on spacecraft since the 1980s and the method was recently used with a number of space missions to derive dust fluxes. Here, we consider the details of dust impacts, subsequent development of the impact generated plasma and how it produces the measured signals. We describe empirical approaches to characterise the signals and compare to a qualitative discussion of laboratory simulations to predict signal shapes for spacecraft measurements in the inner solar system. While the amount of charge production from a dust impact will be higher near the sun than observed in the interplanetary medium before, the amplitude of pulses will be lower because of the different recovery behaviour that varies with the plasma environment. The photocurrent, that is expected to be higher near the Sun, is found to have moderate influence on the spacecraft potential.

The Consultative Committee for Space Data Systems (CCSDS) has issued data compression standards for multi-spectral images aimed to reduce the amount of data transmitted from Earth observation satellites (EOS) to ground stations. Confidentiality of compressed image assumed to be provided by Separate modules which consume mass, power and volume of the space craft. This paper investigate the possibility of applying joint encryption compression to protect compressed image during its transmission by randomized switching between two coding modes in the entropy coder stage of CCSDS-123 compression standard which achieves sufficient security without introducing much complexity to the compression algorithm or affecting compression performance.

The fast development in the production of small, low-cost satellites is propelling an important increase in satellite mission planning and operations projects. Central to satellite mission planning is the resolution of scheduling problem for an optimised allocation of user requests for efficient communication between operations teams at the ground and spacecraft systems. The aim of this paper is to survey the state of the art in the satellite scheduling problem, analyse its mathematical formulations, examine its multi-objective nature and resolution through meta-heuristics methods. Finally, we consider some optimisation problems arising in spacecraft design, operation and satellite deployment systems

The adaptation of LIDAR sensing for space-based applications has grown dramatically over the past decade. Global shutter flash LIDAR has emerged as the LIDAR sensor modality of choice for space craft operations.

With the aim of placing Europe among the world's space players in the strategic area of atmospheric re-entry, several studies on experimental vehicle concepts and improvements of critical re-entry technologies have paved the way for the flight of an experimental space craft. The successful flight of the Intermediate eXperimental Vehicle (IXV), under ESA's Future Launchers Preparatory Programme (FLPP), is definitively a significant step forward from the Atmospheric Reentry Demonstrator flight (1998), establishing Europe as a key player in this field. The IXV project objectives were the design, development, manufacture and ground and flight verification of an autonomous European lifting and aerodynamically controlled reentry system, which is highly flexible and maneuverable. The paper presents, the role of aerodynamics aerothermodynamics as part of the key technologies for designing an atmospheric re-entry spacecraft and securing a successful flight.