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We tested the educational effectiveness of an inquiry-guided approach (Lee et al., 2004; Prince & Felder in "Journal of Engineering Education, 95," 123-138, 2006) to teaching a possible outcome of statistical hypothesis testing known as type 1 error. The approach consisted of showing participants an animated space exploration video. In the video, the commander of a spaceship set out to determine whether the concentration of carbon dioxide on a distant planet exceeded the concentration found on Earth. To make this determination, the commander conducted a series of hypothesis tests. One of the tests suggested that the concentration of carbon dioxide was significantly higher than that on Earth. However, when juxtaposed with the results of the other hypothesis tests, the lone decision to reject the null hypothesis appeared to be a type 1 error. The video's educational effectiveness was evaluated in two ways. First, participants responded to a set of multiple-choice questions on type 1 error, both before and after watching the video. Participants' scores on the multiple-choice test increased significantly from pre-test to post-test. Second, participants rated the video on a set of semantic differential items that tapped its educational effectiveness. On average, participants found the video to be educationally effective. The article concludes with an evaluation of the video's features based on established best practices in statistics education (GAISE College Report ASA Revision Committee, 2016).

Contribution: This article presents a Mars Exploration Control Virtual Simulation Experiment Platform (MEC-vslab), which aims to address the current challenge of limited integration between control engineering education and engineering practice. MEC-vslab is oriented toward the practical needs of Mars exploration engineering. It offers unparalleled advantages by transcending temporal and spatial restrictions and has been applied to several basic control engineering curriculums. Background: Owing to the limited applicability of conventional control engineering education in practical engineering, students encounter difficulties in connecting theoretical knowledge with real-world application scenarios. Due to the impact of environmental complexity and conditional limitations, teaching laboratories cannot realistically reproduce aerospace engineering application environments and problems, making it difficult to develop students' ability to solve unknown engineering problems. Intended Outcomes: MEC-vslab facilitates students in acquiring comprehensive control knowledge, encompassing Mars rovers and drones' dynamics modeling, controller design, and parameter configuration for strongly coupled systems. By engaging with this virtual simulation platform, students develop a profound understanding of cutting-edge control engineering principles, augmenting their proficiency in employing control theory to address practical engineering challenges. Application Design: MEC-vslab as a part of the control-related theoretical curriculum, it encompasses three stages. By completing these stages in succession, students are able to apply their theoretical knowledge toward solving practical engineering problems in a virtual setting. Findings: The analysis based on positive student feedback as well as their learning behavior and questionnaire research that the MEC-vslab is an effective learning tool to integrate control engineering education with high-precision engineering practice needs.

The Scalable, Interactive Model of an Off-World Community (SIMOC) is a computer simulation of a human habitat on Mars. Built upon decades of NASA research and authentic science processes, SIMOC is both a research-grade simulation and an engaging web-based tool for science education. Users access an intuitive web interface to select mission duration, inhabitants and life support modules, crew quarters and greenhouse sizes, food rations and cultivar seeds, and energy production and storage systems. SIMOC engages citizen scientists and learners of all ages in the design of long-duration other-world habitats (with an emphasis on Mars), where the balance between mechanical and plant-based life support will be crucial. For the past three years, SIMOC has enjoyed expanding engagement in virtual and physical classrooms, available for free via the National Geographic Education resource library or local installation. Using a Next Generation Science Standards-aligned curriculum, educators have explored creative applications of SIMOC, from single class time simulations to Mars habitats built from cardboard boxes with live carbon dioxide sensors; from essays on the challenges of human space exploration to full semester design and fabrication of habitats complete with student-built mock-ups in miniature.

What to say to the public about asteroid hazards and how to say it to them? In this article, we relate how our small professional research institution (Klet Observatory, Czech Republic), devoted specifically to Near-Earth Objects (NEOs), together with the educational branch (Ceske Budejovice Observatory and Planetarium, Czech Republic), has developed and implemented a comprehensive educational programme to communicate about our scientific activities. In the beginning of the 1990s, we started some NEO presentations just as a public outreach of Klet Observatory work and an explanation to taxpayers of the usefulness of such research. After thirty years of gaining experience, we understand that education of the wider public, students, journalists, emergency services and decision-makers on hazardous asteroids and planetary defence belongs to the most important tasks of NEO scientists and research institutions (Ticha, J., & Tichy, M. (2018). Klet observatory: 25 years of experience in NEO public education and communication. "Journal of Space Safety Engineering," 5(3-4), 209-210. https://doi.org/10.1016/j.jsse.2018.10.002). This paper presents a case study of NEO and asteroid hazard educational activities in South Bohemia, implemented through the Observatory and Planetarium in Ceske Budejovice, influenced by the long-term Klet NEO programme. We will also mention locally specific connections to NEOs and our future NEO education plans.

Challenged by COVID-19, we sought ways to increase engagement in the virtual classroom, capitalizing on a popular multiplayer game to teach persuasion to undergraduate students. In the game "Among Us[R]," players ("Crewmates") work together to repair their spaceship before it explodes while being attacked by other players ("Impostors"). The structure of the game lends itself to the use of persuasion and influence tactics and provides the basis for a fun, applied learning activity, designed to take 1 hour. We provide detailed instructions for preparing students for the game, running the game, and debriefing. While the constraints resulting from COVID-19 inspired the adoption of this activity for the classroom, we believe it can work well in both virtual and face-to-face classrooms.

Inquiry-based science education has become one of the most effective methodologies to learn science; however, proposals in preschool are scarce. Different factors are responsible for this situation, such as the low self-confidence of teachers to teach science and the belief that young children are unable to develop certain reasoning skills. This study reports the implementation of an inquiry-based science project in a preschool setting, in the context of a preservice teacher's school placement. The project aimed to promote the development of basic and integrated scientific skills, enhance acquisition of conceptual knowledge and make the students enjoy while learning science. The intervention is described thoroughly and illustrated with examples from the real implementation of the theoretical IBSE sequence. At the beginning of the proposal, the students received a hypothetical letter from the astronaut Pedro Duque, in which they were asked for help to plan his trip to living on Mars, a cold planet, with only frozen and saltwater. After some introductory POE (predict, observe, and explain) experiences on the perception of temperature and activities with fresh and saline water, the students performed a piece of research: growing lettuce in four different conditions, combining two variables: temperature and the salinity of water. As the project developed, the students progressively gave better descriptions and justifications, and also showed great interest in performing more "research experiments". For the preservice teacher, the project provided an excellent opportunity to implement academic knowledge in school practice.

A rocket must carry the fuel it expels in order to accelerate its structure and payload. The rocket equation relates the change in speed to the fuel mass expelled. To launch a spacecraft into Earth orbit requires a multi-stage rocket, since otherwise the mass of fuel required would be prohibitive. While the details vary among historical and current launch vehicles, the advantages and physical principles of staging can be demonstrated by analysing the simpler case of a two-stage rocket in free space. I show that a two-stage rocket produces a higher payload speed than a single-stage rocket with the same fuel and structural mass, and introduce the concept of optimal staging to maximise this speed. I also examine how mechanical energy extracted from the expelled fuel is distributed between the stages, payload capsule, and exhaust. A surprising result is that the two-stage rocket deposits more energy into the exhaust stream than its single-stage counterpart. I suggest further investigations that are appropriate for advanced high school or undergraduate students of physics or aerospace engineering. Supplementary materials are provided online for classroom use.

Computational exploration of the compositional spaces of materials can provide guidance for synthetic research and thus accelerate the discovery of novel materials. Most approaches employ high-throughput sampling and focus on reducing the time for energy evaluation for individual compositions, often at the cost of accuracy. Here, we present an alternative approach focusing on effective sampling of the compositional space. The learning algorithm PhaseBO optimizes the stoichiometry of the potential target material while improving the probability of and accelerating its discovery without compromising the accuracy of energy evaluation. [ABSTRACT FROM AUTHOR]

The performance of Hamiltonian Monte Carlo simulations crucially depends on both the integration timestep and the number of integration steps. We present an adaptive general-purpose framework to automatically tune such parameters based on a local loss function that promotes the fast exploration of phase space. We show that a good correspondence between loss and autocorrelation time can be established, allowing for gradient-based optimization using a fully differentiable set-up. The loss is constructed in such a way that it also allows for gradient-driven learning of a distribution over the number of integration steps. Our approach is demonstrated for the one-dimensional harmonic oscillator and alanine dipeptide, a small protein commonly used as a test case for simulation methods. Through the application to the harmonic oscillator, we highlight the importance of not using a fixed timestep to avoid a rugged loss surface with many local minima, otherwise trapping the optimization. In the case of alanine dipeptide, by tuning the only free parameter of our loss definition, we find a good correspondence between it and the autocorrelation times, resulting in a > 100 fold speedup in the optimization of simulation parameters compared to a grid search. For this system, we also extend the integrator to allow for atom-dependent timesteps, providing a further reduction of 25% in autocorrelation times. [ABSTRACT FROM AUTHOR]

We introduce a generalization of the σ-SCF method to approximate noncollinear spin ground and excited single-reference electronic states by minimizing the Hamiltonian variance. The new method is based on the σ-SCF method, originally proposed by Ye et al. [J. Chem. Phys. 147, 214104 (2017)], and provides a prescription to determine ground and excited noncollinear spin states on an equal footing. Our implementation was carried out utilizing an initial simulated annealing stage followed by a mean-field iterative self-consistent approach to simplify the cumbersome search introduced by generalizing the spin degrees of freedom. The simulated annealing stage ensures a broad exploration of the Hilbert space spanned by the generalized spin single-reference states with random complex element-wise rotations of the generalized density matrix elements in the simulated annealing stage. The mean-field iterative self-consistent stage employs an effective Fockian derived from the variance, which is utilized to converge tightly to the solutions. This process helps us to easily find complex spin structures, avoiding manipulating the initial guess. As proof-of-concept tests, we present results for Hn (n = 3–7) planar rings and polyhedral clusters with geometrical spin frustration. We show that most of these systems have noncollinear spin excited states that can be interpreted in terms of geometric spin frustration. These states are not directly targeted by energy minimization methods, which are meant to converge to the ground state. This stresses the capability of the σ-SCF methodology to find approximate noncollinear spin structures as mean-field excited states. [ABSTRACT FROM AUTHOR]

• First quantitative prediction of elements from space debris in 2016–2050. • The predicted elements are Al, Al 2 O 3 , Ti, Fe, Cu and Ag. • The masses of resource elements at 400 km altitude will increase towards 2050. • Al and Ti at 400 km altitude band will increase at least 10 times from 2016 to 2050. • Our model simulation suggests a space resource potential of space debris. The proliferation of space debris poses a significant challenge in modern space exploration, with potential repercussions for the future space environment and activities. Various research and technological developments have addressed these concerns, including estimating the number of space debris orbiting the Earth and its efficient removal. This paper proposes a novel resource-oriented perspective on space debris and focuses on the composition and resource potential of space debris. This study forecasts for the first time the annual mass changes in resource materials (Al, Al 2 O 3 , Ti, Fe, Cu, and Ag) by the year 2050 by employing a debris environment model simulation. Our simulation reveals that the masses of all the studied resource elements in an Earth orbital altitude of 400 km will increase by 2050. For example, Al and Ti at the 400 km altitude band will increase from 3.0 × 106 kg and 3.2 × 105 kg (in 2016) to 3.8 × 107 kg and 4.2 × 106 kg (in 2050), respectively, climbing at least ten times from 2016 to 2050, on the conservative estimates with a high post-mission disposal success rate. These comparative influxes of Al and Ti in 2050 due to space debris are at least 100 times higher than the natural influxes into the Earth's atmosphere due to meteoroids, further highlighting the significance of space debris. Our simulation results suggest that space debris may hold significant space resource potential in the next 25 years but can be a considerable environmental contaminant impeding space sustainability. [ABSTRACT FROM AUTHOR]

Objective. This study aims to determine the optimal structure of the Beam Shaping Assembly (BSA) for an accelerator-based boron neutron capture therapy (BNCT) facility. The aim is to maximize the possible depth of treatment for glioblastoma while ensuring that a treatment time constraint is not exceeded. Approach. To achieve this goal, we utilize a new optimization procedure known as topology optimization. This technique can accurately identify the most optimal structure of a nuclear device, in this case a BSA, to be identified among 9 × 101206 possible structures for the example given in this study. The exploration of such a vast space of configurations is inaccessible to any other method available to date. Main results. The topology optimization generated Air-AlF3–LiF–LiFPE BSA has an original structure that differs significantly from the structures previously tested by the BNCT community. This structure, which combines a ring collimator and a filter cone to mimic the effect of multi-field treatment, generates unprecedented treatment depths, with a treatable depth TD = 10.01 cm and an advantage depth AD = 12.48 cm (for 15 ppm of Boron-10 in blood, with a 3.5 tumor-to-blood Boron-10 concentration ratio), or TD = 10.30 cm and AD = 12.69 cm (for 18 ppm of Boron-10). These depths are much greater than any other design proposed to date by the community. The structure also verifies the latest proposed radiation protection constraints, which set limit values on its out-of-field leakages. Significance. The findings of this study indicate that topology optimization procedures are highly beneficial for the design of BSAs. In particular, the use of ring collimators could significantly improve the quality of BNCT treatments of brain tumors. [ABSTRACT FROM AUTHOR]

• Investigating the issue of computation of multi-revolution NRHO under the ephemeris model. • Analyzing the failure of computation by means of the condition number of STM (State Transition Matrices). • Proposing the strategy of segment selection to improve the convergence of computation. • Computing the lunar L1/L2 NRHOs up to 500 revolutions, the maximal number in the current publications. • No dedicated optimization algorithm or commercial software required for the proposed method. Near Rectilinear Halo Orbits (NRHOs) are vital to manned lunar and deep space exploration, which nowadays are of great interest for different space agencies and in particular with regard to the future space station. However, the required computation of multi-revolution NRHO under the ephemeris model is difficult, especially for the NRHOs with low periapsis relative to the secondary body. This paper explores this issue from the perspective of multiple shooting, first analyzing the influence of the state transition matrices by means of their condition number and then, focusing on a good selection of trajectory segments with suitable patch points. The methodology considerably improves the convergence and the computation under the ephemeris model. Numerical simulations show that at least 30 revolutions can be achieved for NRHOs with perilune radius of less than 12,000 km around L1 or period less than 8.8 days around L2; meanwhile, the number of segments used can be as low as 2 for each single revolution. As for the position of patch points, the first and last points of each revolution should be apart from the Moon, and the distance can be reduced only when the number of segments increases. The proposed method requires no dedicated optimization algorithm or commercial software to produce the multi-revolution NRHOs. [ABSTRACT FROM AUTHOR]

Electrospray technology has been widely applied in many fields, including materials science, chemical engineering, pharmaceuticals, and aerospace exploration. In particular, with the development of commercial space exploration and the demand for miniaturization of micro-nano satellites, capillary electrospray thrusters using ionic liquids as propellants have received extensive attention. However, the use of a single capillary emitter limits the overall performance of the thruster. To further enhance the emission performance of the thruster, the coaxial capillaries emitter with hybrid ionic liquids has been proposed. In this paper, the experimental observation was conducted on the situation where the same ionic liquid was injected into the inner and outer capillaries at different flow rates. It was observed that the outer cone-jet gradually envelops the inner cone-jet to evolute a coaxial cone-jet. Single ionic liquid coaxial electrospray has a limited effect on the stability of the cone-jet. Therefore, 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIM-BF 4) and 1-butyl-3-methylimidazolium hexafluorophosphate (BMIM-PF 6) were separately supplied into the inner and outer capillaries to form a coaxial cone-jet. The results revealed a significant improvement in the current noise spectrum, and it was capable of stable emission current even at higher flow rates. Further analysis of the plume composition was conducted using the time-of-flight method. The results indicated that EMIM-BF 4 and BMIM-PF 6 supplied in outer and inner capillaries respectively as coaxial electrospray can provide the best specific impulse and thrust performances for the electrospray thruster in the conducted experiments. This greatly improves the thrust provided by a single emitter position of the thruster, which expands its application prospects. The coaxial electrospray current with different ionic liquid flow rates is studied. Optimized the cone-jet and current stability by coaxial capillary emitters. The most effective combination of ionic liquids in coaxial emitters is researched. Compared and analyzed specific impulses and thrusts for different emitter forms. [ABSTRACT FROM AUTHOR]

In recent years, prominent spacefaring nations have redirected their attention towards the Moon as a potential avenue for economic prospects and as a pivotal waypoint for extended space exploration endeavors. Nonetheless, a notable concern has emerged regarding the dispersion of lunar dust during lunar landings, a phenomenon that has been associated with documented instances of equipment damage during prior missions. To mitigate these challenges, leading research institutions are actively engaged in endeavors aimed at minimizing the adverse effects of dust dispersal during lunar and extraterrestrial landings. This review paper provides a comprehensive overview of ongoing research and development endeavors focusing on the interaction dynamics between rocket plumes and lunar surfaces, along with the resultant dispersion of lunar dust triggered by rocket plume impingement. Additionally, it presents research efforts aimed at developing lunar dust mitigation technologies. • This paper conducts a survey of research on rocket plumes and lunar dust dispersal. • The challenges posed by lunar dust during past lunar landings are explored. • The effects of lunar dust dispersal through in-situ experiments are investigated. • Previous and ongoing experiments and numerical methods are examined. • Continued research in plume-surface interactions to mitigate hazards is crucial. [ABSTRACT FROM AUTHOR]

This article is dedicated to the development of an innovative approach to optimizing membrane separation processes. The paper introduces the integration of a genetic algorithm (GA) and mesoscopic modeling to enhance the efficiency and accuracy of process parameter optimization. The GA is employed for evolutionary search of optimal parameters, such as pressure, temperature, and membrane material characteristics. The use of evolutionary principles allows for efficient exploration of parameter space, identifying optimal solutions. Mesoscopic modeling serves as a tool for detailed analysis and visualization of membrane separation processes. It involves modeling the interaction of molecules with the membrane surface, enabling a more accurate consideration of the physicochemical aspects of the process. The integration of the GA and mesoscopic modeling creates a unique tool for membrane separation process optimization. The developed approach contributes not only to improving component separation efficiency but also to minimizing energy consumption. The method presented in the article has been successfully tested on model membrane process systems and demonstrated significant improvements compared to traditional optimization methods. The research results confirm the potential of the proposed approach for application in membrane technology industries, opening new perspectives in the field of separation process optimization. [ABSTRACT FROM AUTHOR]

Life support systems in space have been developed to recover a certain amount of oxygen and water. However, we still rely on resupplies for gas tanks, water bags, and food. To achieve sustainable human space exploration, we must also consider the astronauts' wellbeing. This research analyzes and assesses the status of essential life support elements, which are air, water, and food, as well as wellbeing elements, including clothing, hygiene, and healthcare, on the International Space Station. The types and quantities of resupplies for each element were estimated by synthesizing data from multiple sources and compared against baseline values established by the National Aeronautics and Space Administration (NASA) for one crew member per day. To evaluate the qualitative and psychological dimensions of dependence on resupply missions, astronaut feedback and comments documented in reports and articles from space agencies were also analyzed as important references. The results show that resupplies involve not only gas tanks and water bags but also a significant number of spare items to maintain recovery systems. Food completely relies on resupplies, and regarding wellbeing elements, although the mass supplied from Earth seems to meet the space agency's requirements, astronauts feel uncomfortable wearing the same clothes and using the same towels for days, especially exercise clothes, which can develop odors. It was also discovered that each resupply mission is inefficient as resupplies account for only 0.21% of the total launch mass. Relying on resupply missions has been associated with negative effects on both physical and psychological aspects, such as anxiety about the risk of running out of life support consumables, issues with stowage and odors caused by waste, and stress due to complicated cargo unloading and loading transfer operations. As humans explore the Moon and beyond, frequent resupplies will become impractical due to higher launch costs and longer delivery times, and suggestions for developing technologies to realize a sustainable human presence in space are being proposed. [ABSTRACT FROM AUTHOR]

Non-targeted screening with liquid chromatography coupled to high-resolution mass spectrometry (LC/HRMS) is increasingly leveraging in silico methods, including machine learning, to obtain candidate structures for structural annotation of LC/HRMS features and their further prioritization. Candidate structures are commonly retrieved based on the tandem mass spectral information either from spectral or structural databases; however, the vast majority of the detected LC/HRMS features remain unannotated, constituting what we refer to as a part of the unknown chemical space. Recently, the exploration of this chemical space has become accessible through generative models. Furthermore, the evaluation of the candidate structures benefits from the complementary empirical analytical information such as retention time, collision cross section values, and ionization type. In this critical review, we provide an overview of the current approaches for retrieving and prioritizing candidate structures. These approaches come with their own set of advantages and limitations, as we showcase in the example of structural annotation of ten known and ten unknown LC/HRMS features. We emphasize that these limitations stem from both experimental and computational considerations. Finally, we highlight three key considerations for the future development of in silico methods. [ABSTRACT FROM AUTHOR]

Nano-satellites are essential tools for various applications, including scientific experiments, deep space exploration and astronomical observation. Achieving precise model predictions is crucial for their successful operation. To address the intricate constraints of nano-satellites and enhance control performance, the Model Predictive Control (MPC) algorithm is an effective solution. However, implementing an MPC-based attitude control system in actual engineering scenarios presents significant challenges, primarily due to the substantial computational burden, especially given the limited onboard computing resources of nano-satellites. In this paper, we introduce a modified adaptive self-triggered model predictive control (ST-MPC) algorithm designed to stabilize the attitude of nano-satellites, while simultaneously reducing communication and computational overhead compared to traditional MPC methods. The proposed self-triggered mechanism dynamically determines the next trigger time according to the system state. Moreover, we incorporate considerations for the efficiency of actuators to address the constraints imposed by the magnetic torque characteristics within the modified self-triggered mechanism. Additionally, a strategy for adaptive prediction horizon is proposed to balance computation load and control accuracy. The results of our simulations demonstrate the effectiveness of the modified ST-MPC algorithm in comparison to both traditional MPC and standard ST-MPC approaches. This algorithm may have the potential to significantly impact attitude control applications for nano-satellites. [ABSTRACT FROM AUTHOR]

Laser ablation has been extensively studied by researchers due to its high precision, high efficiency processing capabilities, and wide range of application potentials. However, in a vacuum environment, due to the complexity of experimental conditions, specific application scenarios, and interdisciplinary interferences, more in-depth research on the ablation behavior of high-intensity lasers in vacuum is still insufficient. In response to such issues, experiments were conducted on titanium alloy perforation using a nanosecond laser in a vacuum environment. The variations in ablation depth and volume as functions of pulse energy, pulse number, and defocus were investigated. Both the depth and volume ablation efficiencies were calculated, and the three-dimensional morphology of the ablation holes was captured. Additionally, the ablation plume was observed to support the research conclusions. The results indicate that within the number of high-intensity laser pulses, the ablation depth per pulse can be increased by more than four times, and the average ablation volume per pulse can reach 0.97 µm3/µJ. The enhanced sputtering of molten material during the multi-pulse laser ablation process in a vacuum environment is identified as the primary factor contributing to the increased ablation efficiency. With the advancement of science and technology and the growing demand for applications, this research is crucial for the further development of fields such as space exploration and technology, advanced manufacturing technology, and basic scientific research. [ABSTRACT FROM AUTHOR]

Feature selection is a preprocessing step for various classification tasks. Its objective is to identify the most optimal features in a dataset by eliminating redundant data while preserving the highest possible classification accuracy. Three improved binary Grey Wolf Optimization (GWO) approaches are proposed in this paper to optimize the feature selection process by enhancing the feature selection accuracy while selecting the least possible number of features. Each approach combines GWO with Particle Swarm Optimization (PSO) by implementing GWO followed by PSO. Afterwards, each approach manipulates the solutions obtained by both algorithms in a different way. The objective of this combination is to overcome the GWO stuck-in-local-optima problem that might occur by leveraging the PSO-wide search space exploration ability on the solutions obtained by GWO. Both S-shaped and V-shaped binary transfer functions were used to convert the continuous solutions obtained from each proposed approach to their corresponding binary versions. The three proposed approaches were evaluated using nine small-instance, high-dimensional, cancer-related human gene expression datasets. A set of comparisons were made against the original binary versions of both GWO and PSO algorithms and against eight state-of-the-art feature selection binary optimizers in addition to one of the recent binary optimizers that combines PSO with GWO. The evaluation results showed that one of the proposed S-shaped and V-shaped approaches achieved 0.9 and 0.95 average classification accuracy, respectively, while selecting the fewest number of features. The results also confirmed the superiority of one of the proposed V-shaped approaches when compared with the original binary GWO and PSO approaches. Moreover, the results confirmed the superiority, in most of the datasets, of one of the three approaches over the state-of-the-art approaches. Finally, the results revealed that the best approach in terms of classification accuracy, fitness value, and number of selected features had the highest computational complexity. [ABSTRACT FROM AUTHOR]

As humanity embarks on Space Age II, the revival of human space exploration brings unprecedented opportunities and challenges. The commercial spaceflight industry has significantly lowered barriers, enabling government agencies to pursue more ambitious missions to the Moon and Mars in the coming decades. This renewed momentum necessitates a more comprehensive approach to the psychological and wellbeing aspects of human space exploration. Drawing on the authors training as a psychologist and co-founder of digital technology startup, this paper explores how immersive technologies, particularly Virtual Reality (VR) and advanced interfaces can address some of the unique psychological and social challenges posed by isolated, confined, and extreme (ICE) environments. It highlights the importance of integrating scientific and psychological theories into digital therapies to create comprehensive evidence-based interventions. These interventions aim to significantly improve the quality of life and mission success for future space explorers, offering more than stand-alone one-off solutions. This will require continuous innovation and research in leveraging advanced technologies to meet the evolving demands of human space exploration and habitation. [ABSTRACT FROM AUTHOR]

This study focuses on the analysis of a unique composition between two well-established models, known as the Logistic–Gauss map. The investigation cohesively transitions to an exploration of parameter space, essential for unraveling the complexity of dissipative mappings and understanding the intricate relationships between periodic structures and chaotic regions. By manipulating control parameters, our approach reveals intriguing patterns, with findings enriched by extreme orbits, trajectories that connect local maximum and minimum values of one-dimensional maps. This theory enhances our perception of structural organization and offers valuable perceptions of the system behaviors, contributing to an expanded understanding of chaos and periodicity in dynamic systems. The analysis reveals Complex Sets of Periodicity (CSP) in the parameter space, characterized by superstable curves that traverse their main bodies. The exploration of different combinations of parameters shows cascades of CSP structures with added periods and are organized based on extreme curves. This investigation offers valuable discoveries of the dynamics of dissipative mappings, opening avenues for future explorations in chaotic systems. [ABSTRACT FROM AUTHOR]

Deep space exploration is one of the key development directions in the aerospace field. With the significant increase in detection distance, the traditional space exploration methods may be ineffective due to effects such as signal energy attenuation and channel delay. There is an urgent need for a miniaturized, quasi-real-time, high-precision space velocity measurement instrument to be mounted on deep space aircraft and provide autonomous navigation. Spatial heterodyne spectral velocimetry technology is a newly proposed high-precision velocimetry method in recent years, and relevant research units have also obtained excellent measurement results in applications. However, this technology originally used laser light sources for active detection, which differs from the passive detection based on stellar light sources required for deep space vehicles in terms of prerequisites. Therefore, this article focuses on the technical route and feasibility exploration of using spatial heterodyne spectral velocimetry technology for stellar absorption spectrum and proposes a practical measurement scheme based on the technical principle of the background light synchronous cancellation method. We measured the radial velocity difference caused by the sun's rotation at different positions on the solar image plane through outside validation experiments built in a simulated environment on the ground and obtained the experimental data with measurement deviation about 90 m/s and standard deviation about 55 m/s. The experimental results indicate that, under the current stability conditions of ground-based solar observation, we have achieved the same level of measurement accuracy as large ground-based telescopes by using instruments and equipment of much smaller size. It can be considered that the spatial heterodyne spectral velocity measurement scheme proposed in this article has achieved feasibility verification based on stellar spectral detection capability under the premise of instrument miniaturization and quasi-real-time processing. The research content provides a preliminary verification for the development of spatial heterodyne spectral velocimetry technology in the aerospace field and also provides reference for the realization of high-precision autonomous navigation capability in future aerospace technology. [ABSTRACT FROM AUTHOR]

Purpose: Human presence in space is increasingly frequent, but we must not forget that it is a hostile environment. We aimed to study the characteristics of experimental scenarios, to obtain data on human response to isolation, disruption of circadian rhythm and high levels of psychophysical stress. Methods: In these experiments, we evaluated stress response in five young healthy subjects inside an earth-based moon-settlement-like habitat during a 1-week long analog astronaut mission. Wearable devices were used to monitor daily step count of the subjects, physical activity, heart rate during physical exercise and at rest, and sleep parameters. From saliva and urine samples collected every day at awakening, we studied oxy-inflammation biomarkers and hormones (stress and appetite) were studied too. Results: At the end of the week, all subjects revealed an increase in oxidative stress and cortisol levels but no inflammation biomarkers variations, in conjunction with increasing time/daily exercise. Furthermore, a significant decrease in hours of sleep/day, sleep quality, and REM phase of sleep was recorded and correlated with the increase of reactive oxygen species. Conclusion: Oxidative stress increased in a short period of time and may be attributed to the influence of psychological stress during confinement, as well as increased exercise and decreased amount of sleep. On a long-term basis, this could impact performance. [ABSTRACT FROM AUTHOR]

[Display omitted] In order to understand the basic mechanisms affecting emulsion stability, the intrinsic dynamics of the drop population must be investigated. We hypothesize that transient ballistic motion can serve as a marker of interactions between drops. In 1G conditions, buoyancy-induced drop motion obscures these interactions. The microgravity condition onboard the International Space Station enable this investigation. We performed Diffusing Wave Spectroscopy (DWS) experiments in the ESA Soft Matter Dynamics (SMD) facility. We used Monte Carlo simulations of photon trajectory to support data analysis. The analysis framework was validated by ground-based characterizations of the initial drop size distribution (DSD) and the properties of the oil/water interface in the presence of surfactant. We characterized the drop size distribution and found to be bi-disperse. Drop dynamics shows transient ballistic features at early times, reaching a stationary regime of primarily diffusion-dominated motion. This suggests different ageing mechanisms: immediately after emulsification, the main mechanism is coalescence or aggregation between small drops. However at later times, ageing proceeds via coalescence or aggregation of small with large drops in some emulsions. Our results elucidate new processes relevant to emulsion stability with potential impact on industrial processes on Earth, as well as enabling technologies for space exploration. [ABSTRACT FROM AUTHOR]

To enhance the balance between global and local search capabilities of Dung Beetle Optimization (DBO) algorithm, this study proposes a multi-strategy hybrid improvement, resulting in Dynamic Population Dung Beetle Optimization (DPDBO) algorithm. Initially, a Piecewise Linear Chaotic Map (PWLCM) is employed for population initialization, thereby improving the uniformity of the initial population distribution and, consequently, enhancing the global search capability of DPDBO. Subsequently, the disorienting behavior of the ballrolling dung beetle is modeled to expand the exploration of the solution space by integrating the original linear search method with an enhanced spiral search strategy. Additionally, a dynamic population strategy is introduced to adaptively allocate ball-rolling and stealing dung beetles, effectively balancing the exploration and exploitation capabilities of DPDBO. Comparative analysis of DPDBO against six other meta-heuristic algorithms (DBO, Sparrow Search Algorithm (SSA), Harris Hawks Optimization (HHO), Whale Optimization Algorithm (WOA), Genetic Algorithm (GA), and Sine Cosine Algorithm (SCA)) using CEC2017 and CEC2022 test functions demonstrates that the proposed algorithm achieves faster convergence, higher optimization accuracy, and greater robustness. Furthermore, DPDBO is applied to three engineering applications (e.g., sensor coverage optimization, tension spring design, and welded beam design) showcasing its efficacy in solving real-world engineering problems. [ABSTRACT FROM AUTHOR]

The act of planting a flag on the moon carries immense significance in the realm of human space exploration. Therefore, this paper develops a discrete-element method–finite-element method (DEM–FEM) coupling algorithm to simulate the flag planting process. To enhance the stability of a flagpole installed on the lunar surface, the structure of the flagpole is optimized, with the bottom end designed as a cone and a stabilizer bracket added. Three flag insertion methods are proposed: direct insertion, percussion insertion, and rotation insertion. The stability of the flagpole given external disturbances is thoroughly discussed. The results demonstrate that the cone design at the bottom of the flagpole effectively enhances its depth in the soil. Although the addition of a stabilizer bracket does not facilitate the flagpole's penetration into the lunar surface, it increases its resistance to external interference. Given appropriate conditions, the three insertion methods can significantly increase the depth of the flagpole into the soil. The stability analysis reveals that, in the face of constant external interference, flagpoles with greater depth experience less horizontal displacement and require a larger external load to collapse, indicating enhanced stability. Overall, this research provides practical solutions and theoretical references for the manual placement of flags on the lunar surface. [ABSTRACT FROM AUTHOR]

The article outlines the key aspects of the Moon Agreement, adopted in 1979 and entered into force in 1984. Topics include the peaceful use of celestial bodies and their environmental protection, the common heritage of the Moon and its natural resources, and the establishment of an international regime for the exploitation of these resources.

The article reflects on the personal and professional experiences of an astronaut, emphasizing the physical, mental, and emotional challenges faced during space missions. Topics include the interdisciplinary forum on space exploration convened by the Calgary Institute for the Humanities, the collaboration required in space exploration across disciplines and cultures, and the importance of integrating humanities, arts, and social sciences in discussions about space exploration.

The article discusses Indigenous perspectives on land, space, and colonialism. Topics include the contrasting views of land ownership between Settler and Indigenous cultures, the role of the night sky and space in the Indigenous ecosystem, and the violation of Indigenous rights in space exploration and treaty considerations.

In the last few years, Earth's Moon has become a target of renewed interest, not only for scientific inquiry, but for exploitation as a commercial resource and a stepping stone to the rest of the solar system. Underpinning the idea that the Moon's mineral resources exist for the benefit of humanity is a widespread perception that the Moon is a dead world. But is this true, and what are the implications of treating the Moon as dead? This essay is an exploration of human engagements with the Moon, particularly those of the so-called spacefaring nations, as we enter a new phase of space exploration. [ABSTRACT FROM AUTHOR]

Plants in space face unique challenges, including chronic ionizing radiation and reduced gravity, which affect their growth and functionality. Understanding these impacts is essential to determine the cultivation conditions and protective shielding needs in future space greenhouses. While certain doses of ionizing radiation may enhance crop yield and quality, providing "functional food" rich in bioactive compounds, to support astronaut health, the combined effects of radiation and reduced gravity are still unclear, with potential additive, synergistic, or antagonistic interactions. This paper investigates the combined effect of chronic ionizing radiation and reduced gravity on Brassica rapa seed germination and microgreens growth. Four cultivation scenarios were designed: standard Earth conditions, chronic irradiation alone, simulated reduced gravity alone, and a combination of irradiation and reduced gravity. An analysis of the harvested microgreens revealed that growth was moderately reduced under chronic irradiation combined with altered gravity, likely due to oxidative stress, primarily concentrated in the roots. Indeed, an accumulation of reactive oxygen species (ROS) was observed, as well as of polyphenols, likely to counteract oxidative damage and preserve the integrity of essential structures, such as the root stele. These findings represent an important step toward understanding plant acclimation in space to achieve sustainable food production on orbital and planetary platforms. [ABSTRACT FROM AUTHOR]

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The aerodynamic performance of an aircraft can be significantly enhanced by incorporating wingtip devices, such as winglets, which primarily reduce lift-induced drag caused by wingtip vortices. This study introduces a comprehensive optimization framework for designing winglets on a Class I fixed-wing mini-UAV, aiming to maximize aerodynamic efficiency and operational performance. Using surrogate-based optimization (SBO) techniques, this research developed winglet geometries with varying geometric parameters such as length, cant angle, and sweep angle with their performance being evaluated through high-fidelity Computational Fluid Dynamics (CFD) simulations. These simulations utilized Reynolds-Averaged Navier–Stokes (RANS) equations coupled with the Spalart–Allmaras turbulence model to capture the intricate flow dynamics around the UAV in different flight phases. The integration of SBO techniques allowed for an efficient exploration of the design space while reducing computational costs associated with iterative high-fidelity simulations. In particular, the proposed SBO framework optimized the UAV's aerodynamic characteristics, including lift-to-drag ratio and drag reduction, followed by a stability and control analyses to ensure balanced performance for the optimal configurations. Dynamic stability evaluations revealed improved flight characteristics, maintaining control across operational envelopes. The results demonstrated a significant improvement in aerodynamic coefficients, range, endurance, and reduction in battery consumption throughout the entire UAV operational envelope, underscoring the potential of innovative winglet designs to enhance UAV performance across diverse mission profiles. [ABSTRACT FROM AUTHOR]

Autonomous systems such as space‐ or underwater‐exploration robots or elderly people assistance robots often include an artificial intelligence (AI) planner as a component. Starting from the initial state of a system, an AI planner automatically generates sequential plans to reach final states that satisfy user‐specified goals. Generating plans having a minimum number of intermediate steps or taking the least time to execute is usually strongly desired, as these plans exhibit minimal costs. Unfortunately, testing if an AI planner generates optimal plans is almost impossible because the expected cost of these plans is usually unknown. Based on mutation adequacy test suite selection, this article proposes a novel metamorphic testing framework for detecting the lack of optimality in AI planners. The general idea is to perform a systematic but non‐exhaustive state space exploration from the initial state and to select mutant‐adequate states to instantiate new planning tasks as follow‐up test cases. We then check a metamorphic relation between the automatically generated solutions of the AI planner for these new test cases and the cost of the initial plan. We implemented this metamorphic testing framework in a tool called MorphinPlan. Our experimental evaluation shows that MorphinPlan can detect non‐optimal behaviour in both mutated AI planners and off‐the‐shelf, configurable planners. It also shows that our proposed mutation adequacy test selection strategy outperforms three alternative test generation and selection strategies, including both random state selection and random walks through the state space in terms of mutation scores. [ABSTRACT FROM AUTHOR]

The article discusses the importance of creative review in anthropology, emphasizing the value of engaging with non-traditional forms of scholarly work such as poetry, visual art, and performance. It argues that creative anthropology is equal to traditional forms and should be taken seriously in academic discourse. The article advocates for a shift in the culture of peer review towards a more dialogical and open-ended approach, promoting critical empathy as a key aspect of engaging with creative work. By valuing creative exploration as a legitimate form of knowledge production, anthropology can evolve in a more inclusive and dynamic manner. [Extracted from the article]

AbstractLaser-induced breakdown spectroscopy (LIBS) technology has been widely used in many fields including industrial production, space exploration, medical analysis, environmental pollution detection, etc. However, the stability problem of LIBS is one of the core problems for its further development. Solutions in the LIBS field in recent decades were summarized and classified from the physical mechanism and analysis method. In particular, the processing methods based on the features of the plasma image and reconstructed image were analyzed and expounded. At the physical mechanism level, the system improvement strategy, environmental modulation strategy, and sample pretreatment improvement strategy were summarized and classified as a pre-improvement strategy. At the analysis method level, two kinds of correction strategies were concluded according to the difference between the feature mediums of the plasma spectrum and image, which were classified as a later improvement strategy. Strategies and methods were discussed in detail, which can provide a basic architecture and reference for the research of LIBS stability improvement. Moreover, the potential developing trend for this topic was proposed. [ABSTRACT FROM AUTHOR]

The innovative thermal management system named Two-Phase Mechanically Pumped Loop (2PMPL) has been investigated to design probes for Venus exploration. This study aims integrating the 2PMPL evaporator inside the probe shell, using the Laser Powder Bed Fusion technique, to reduce the thermal system size and to increase the payload. In this paper, four evaporator designs have been developed and compared to the latest available reference solution. The overall assessment of those designs has been performed by comparing the results of basic Computational Fluid Dynamics analysis, structural behavior, mass and Three-Phase Contact Line (TPCL) length, highlighting specific strengths of each solution. [ABSTRACT FROM AUTHOR]

Spectroscopy plays a pivotal role in discerning the chemical and biochemical compositions of analytes, significantly impacting chemical and material analysis, disease diagnosis, environmental monitoring, and space exploration. Despite the widespread demand for optical spectrometers in both industry and academia, their deployment in many practical applications is hindered by the high costs, large footprints, and mechanical vibration sensitivity of conventional spectrometers. These problems are addressed by integrated optical spectrometers. Silicon photonics offers a potentially low‐cost platform for ultracompact integrated optical spectrometers, leveraging the complementary metal‐oxide‐semiconductor (CMOS) compatible fabrication technology and high flexibility in on‐chip light manipulation of high‐index waveguides. The integrated optical spectrometers on silicon photonics platforms provide promising solutions for developing ultra‐compact and cost‐effective spectral analyzers in various applications. This review paper overviews recent advancements in integrated optical spectrometers on silicon photonics platforms over the past decades, focusing on their fundamental principles, design methodologies, spectral performances, and potential applications. By blending foundational knowledge with cutting‐edge research, this review aims to involve researchers from different fields, including spectroscopy, materials science, astronomy, environmental engineering, and beyond. [ABSTRACT FROM AUTHOR]

The idea of synthetic torpor, an artificial state resembling the hypo-metabolic state of torpor/hibernation, has recently gained significant scientific attention. Building on pioneering research demonstrating the protective effects of torpor against radiation in mammals, this mini-review aims to evaluate its scientific validity. We will explore the theoretical foundations, practical applications, and potential challenges linked to synthetic torpor. By critically examining the current knowledge, we aim to determine if synthetic torpor is a scientifically viable and achievable concept with broad implications for fields such as space exploration and healthcare. [ABSTRACT FROM AUTHOR]

ABSTRACT Molecular dynamics (MD) and the material point method (MPM) are both particle methods in spatial discretization. Molecular dynamics is a discrete particle method that is widely applied to predict fundamental physical properties and dynamic materials behaviors at nanoscale. The MPM is a continuum‐based particle method that was proposed about three decades ago to simulate large‐deformation problems involving multiphase interaction and failure evolution beyond the nanoscale. However, it is still a challenging task to validate MD responses against the experimental data due to the spatial limitation in impact and/or shock tests. The objective of this investigation is therefore to compare the MPM and MD solutions for the impact responses of porous solids at nanoscale. Since the governing equations for MD and explicit MPM are similar in temporal domain with different spatial discretization schemes, the MPM solutions could be verified against the MD ones, and the MD solutions might then be indirectly validated against the MPM ones as validated beyond the nanoscale. Since both MD forcing functions and MPM constitutive modeling are well‐formulated for metallic solids, we report a comprehensive comparative study of 40×40×40nm$40\ \times \ 40\ \times \ 40\ {\mathrm{nm}}$ porous and non‐porous gold cubic targets impacted by full density non‐porous gold cubic flyers using the MPM and MD, respectively. The overall deformation patterns and particle‐velocity histories are demonstrated and analyzed, as obtained with the two particle methods. It appears that the MD and MPM solutions are consistent in capturing the physical responses, which shows the potential of using the MPM for multiscale simulations of extreme events involving porous solids, such as underground penetration and space exploration. In addition, MD solutions might be indirectly validated against the MPM ones for evaluating geological responses to extreme loadings, which provides an alternative route for multiscale verification and validation. [ABSTRACT FROM AUTHOR]