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The Mars rotorcraft is an aerial exploration platform capable of repeated take-offs and landings to extend the range of rover explorations. NASA's Ingenuity helicopter is a full y functioning coaxial helicopter for technology demonstration. Increasing the rotor diameter or the number of blades can enhance the load capacity of the coaxial helicopter but would make it difficult to be folded. A more suitable configuration for Mars exploration is the multi-rotor aircraft, which has a stronger load capacity with the same rotor diameter. Although the aerodynamic performance and operational capabilities of the Mars multi-rotor aircraft have been partially considered, mechatronic system design and autonomous flight control have not been fully addressed. Harbin Institute of Technology and China Academy of Space Technology jointly proposed a deployable Mars quadcopter for air patrol and sampling with a sample mass of 100 g. This paper presents a concept for a Mars quadcopter and its mission operations, including operational procedures and flight modes, to provide a framework for future Mars flight sampling missions. We describe the structure and avionics architecture of the Mars quadcopter. Then, we present the hardware and software design of the guidance, navigation, and control (GNC) system to illustrate the autonomous flight control method. Finally, we introduce the deployment mechanism of the Mars quadcopter. • A foldable Mars quadcopter improves the efficiency and flexibility of Mars sample return tasks. • Five-module avionics system augments the Mars quadcopter for survival and operation. • A navigation method combining inertial and binocular vision enables autonomous flight on Mars. • The guidance system based on mode commands can independently plan exploration operations. [ABSTRACT FROM AUTHOR]

The Moon is a highly valued destination for human space exploration because it is close and it contains a wide array of lunar and Solar System science targets, which include resources that could be used to sustain humans on the lunar surface. These resources have the potential to enable sustainable human space exploration, develop a vibrant cislunar economy, and directly benefit society here on Earth. However, recent rhetoric about the importance and value of these resources has used the term as if we know they are reserves. An immediate and vital next step has not yet been realized to define the reserve potential of such resources, and that is designing and implementing a coordinated international lunar resource evaluation (prospecting) campaign. This paper outlines the issues that need to be addressed by such a campaign, including why it needs to be international in nature and how the coordination can be started and evolved, as well as exploring the benefits that would come from prospecting on the Moon. • A distinction between lunar resources and lunar reserves is defined. • Roadblocks in the in-situ resource value chain are highlighted. • Reserve potential of lunar resources requires a coordinated prospecting campaign. • The prospecting campaign must be international due to the scale of the task. • Coordination can start at the grassroots level with current and scheduled missions. [ABSTRACT FROM AUTHOR]

Virtual reality (VR) and augmented reality (AR) are rapidly developing technologies that may have important healthcare-related applications, including the possible evaluation of the health and performance of astronauts. Advances in the fields of VR/AR and space exploration have independently progressed; however, over the last decade synergies and overlapping applications have emerged between spaceflight and extended reality. This paper is intended to be a resource to update the medical community on the current and future integration of VR and AR into space exploration, particularly as this integration relates to astronaut health. We highlight how these technologies are used in terrestrial healthcare with specific attention to visual function. Furthermore, we elaborate on emerging VR applications being developed for future spaceflight. The paper discusses the current state of the art, such as the Apple Vision Pro headset, and outlines key challenges like mass and volume constraints, power limitations, and the heightened cognitive and physical demands of space travel. It also addresses the potential of VR/AR technologies to mitigate these issues through efficiency, stress reduction, and exercise motivation. Finally, we emphasize the benefits that these technologies provide to overcome possible barriers to long duration spaceflight and manned exploration missions, including spaceflight associated neuro-ocular syndrome (SANS). • Virtual reality (VR) and augmented reality (AR) are rapidly developing technologies that may have important healthcare-related applications, including the possible evaluation of the health and performance of astronauts. • This paper is intended to be a resource to update the medical community on the current and future integration of VR and AR into space exploration, particularly as this integration relates to astronaut health. • We highlight how these technologies are used in terrestrial healthcare with specific attention to visual function. Furthermore, we elaborate on emerging VR applications being developed for future spaceflight. [ABSTRACT FROM AUTHOR]

Balloon-based exploratory platforms, or aerobots, are a budding planetary exploration technology for Venus to collect scientific data in-situ while keeping a safe distance from the highly inhospitable surface of Earth's "evil twin". Such a mission is expected to deploy and inflate the aerobot during the system's initial descent through the Venusian atmosphere, rather than launched from the surface. The analysis of the entry, descent and float (EDF) sequence of the aerobot is accordingly a delicate and fundamental part of the aerobot design, and generally where the envelope undergoes the largest loads. The inflation phase in particular plays an essential role, especially for variable-altitude aerobots that can have multiple-envelopes with different inflation requirements. This paper addresses a collection of preliminary considerations about the inflation phases of a Venus aerobot – starting from the end of deployment to completion of reaching an equilibrium altitude – where the nominal mission flight profile would then begin. We include two different inflation sequences, highlighting issues and threats, utilizing a simulation of the inflation dynamics of the aerobot conducted in MATLAB. The paper also presents results from a set of rapid inflation experiments, conducted on a subscale prototype of the aerobot, aimed at an initial assessment of feasibility and response of the materials involved. • Inflation sequence design for a variable-altitude aerobot at cloud-level on Venus. • Sequence modification to reduce peak loads on the aerobot. • Constraint-driven analysis to evaluate the impact of the model's initial parameters. • Laboratory demonstration of the inflation utilizing a subscale aerobot prototype. [ABSTRACT FROM AUTHOR]

How does a country embark on large-scale R&D programs? Among R&D programs, this is an intriguing question for large scale Science and Technology (S&T) projects such as space programs, because of the necessity for large resource commitments, and the difficulty of being accountable to the taxpayers when the outcome is not always known. It can be assumed that engineers, scientists, bureaucrats, and politicians play respective roles. This paper aims to shed light on the specific role of politics, through the examples of policies of and decisions by NAKASONE Yasuhiro. Nakasone was the minister for science and technology (1959–1960, 1972), and later became the prime minister (1982–1987). He played a crucial role in establishing the Science and Technology Agency and the National Space Activities Council in the 1950s, which would be the foundational institutions responsible for space policy for the next half century. As prime minister, he decided to participate in the Space Station program. Within his vision for Japan for the 21st century, he emphasized the need for radical change in economic policy, education, defense and S&T investment. He was one of the few politicians that had vision to promote S&T and recognized the strategic value to the nation. He was able to explain to the nation why Japan should promote the development of a launch vehicle, when the engineers faced development difficulties in doing so. Thus, he was influential both in the policy layer and in promoting specific programs to support his national vision. Politics intersects with S&T projects because of the uncertainty and tradeoffs associated with these efforts. Japan did not address space programs for national security and commercial space for a long time. It is a politician's role to create institutions, to allocate resources and, more importantly, to explain to the taxpayers why policy measures or programs are necessary. R&D investment is a societal activity: it reflects the social, political, and economic situation, as well as being important for diplomacy and international relations. Bearing in mind that it would be misleading to attribute the initiation of largescale S&T projects to the leadership of a single individual, this paper will attempt to show the driving forces behind, and fundamental objective of Japan's space policy, in addition to the historical shift in that policy by examining the influence of this notable politician. • Nakasone played the key role in establishing institutions promoting space development in post-war Japan. • Nakasone made the best use of close relationships with the U.S. in promoting Japan's space activities. • Nakasone made decisions on space policy process, resource allocation with vision, thus integrating the stakeholders. [ABSTRACT FROM AUTHOR]

This paper presents the high-fidelity physical modeling of a Thrust Vector Control (TVC) system operated by Electro-Mechanical Actuators (EMAs) for Reusable Launch Vehicles (RLVs). In contrast to simplified, often linear, models, high-fidelity physical models enable a better assessment of the actual system performance and a deeper verification of the on-board software robustness against disturbances, unmodeled dynamics or degradation. This aspect is essential to enable the reusability concept as driven by long-term reliability requirements. Moreover, critical systems like Fault Detection, Isolation and Recovery (FDIR) logic, whose robustness and efficacy are often difficult to prove, can be thoroughly tested without requiring hardware experiments with eventual invasive modifications for fault injections. This work captures the whole dynamics of the EMA and TVC components, including the power drive electronics, the electrical motor, and the mechanical transmission for the EMA, as well as the mechanical properties of the engine nozzle acting as a load. The resulting differential algebraic equation system is modeled in the Modelica acausal object-oriented modeling language. An ad-hoc framework is implemented to guarantee flexibility and modularity, which allows models with different fidelity levels to be easily exchanged to achieve the simulation objectives and needed accuracy level. The impact of the different models on the closed-loop TVC dynamics is analyzed in both the frequency and time domain, and then benchmarked with a realistic RLV mission. The results show that the high-fidelity physical models provide a better understanding of the more complex effects governing the TVC dynamics and can, in turn, effectively improve its requirement definition process. • The physical modeling and simulation of an EMA-based TVC system is presented. • High-fidelity physical models help assessing TVC system control software performance. • EMA component models with incremental fidelity levels are proposed. • EMA and TVC system models are integrated in a Modelica-based framework. • Different closed-loop responses are analyzed in the frequency and time domains. [ABSTRACT FROM AUTHOR]

Development of efficient and safe energy systems for space objects includes ensuring fire safety. This problem requires a deep understanding of influence of gravitational forces on combustion processes, which explains the importance of studying this issue. The paper analyzes the dynamics of inverted conical methane-air flame under conditions of normal and reverse gravitational force with external acoustic excitation. Applied frequencies of acoustic excitation could be parasitic or be produced during proper work of different technical systems of aircraft. High speed recording of flame chemiluminescence and PIV analysis were conducted. Decomposition of flow vector pictures into the modes was calculated using POD method. Energy contribution into the flow was analyzed for its separate elements at the different frequencies of excitation. At the high excitation frequencies vortex generation intensity in the shear layer with reverse gravity is about the same as it was observed in the experiments with normal gravity direction, that could indicate dominance of acoustic mechanism of the vortexes stimulation over the mechanism of shear instability. At external excitation frequency equals 240 Hz significant growth of shear vortex diameters and increasing of perpendicular oscillations amplitude of flame branches were obtained. Thereby in such experiment with 240 Hz external acoustic excitation the most intensive large scale instability of flow was observed. • The smallest vortices sizes are observed at 0 and 60 Hz excitation frequencies. • At excitation of 160, 240 and 420 Hz the vortices are non-affected by the gravity. • Vortice sizes and transverse oscillation range approach maximum at 240 Hz excitation. [ABSTRACT FROM AUTHOR]

Textbooks have a central role in chemistry education and represent the intended chemistry curriculum at the national level. This paper focuses on analysing the intended chemistry curriculum as represented by the visual representations and the activities for students in the textbook sets in relation to the topics of the Slovenian National Chemistry Curriculum both at the primary and secondary school levels. The analysis involved all textbook sets approved by the national representatives for the 2021/2022 school year. The results revealed that in most of the curriculum topics in the analysed Slovenian chemistry textbook sets, the curriculum orientation structure of the discipline prevails and the everyday life orientation is present for both primary and secondary schools. To improve the relevance of the textbook sets for students, the currently rare presence of history of chemistry, environmental orientation, and technology and industry orientation and the lack of the use of socio-scientific orientation should be overcome. It would be valuable if further studies in textbook sets would also address the intended chemistry curriculum from a more holistic perspective. [ABSTRACT FROM AUTHOR]

Sphingomyelin synthase 2 (SMS2) has emerged as a promising target for atherosclerosis threatment. However, the availability of selective SMS2 inhibitors and their associated pharmacological properties remains limited. This research paper explores various QSAR modeling techniques applied to a range of compounds acting as SMS2 inhibitors. Multiple distinct QSAR modeling methodologies were employed, including conformation-independent, GA-MLR and 3D based QSAR modeling, and their mutual correlations were investigated, Various statistical methods were applied to assess the quality, robustness, and predictive capacity of these developed models, yielding favorable results. Furthermore, molecular fragments derived from SMILES notation descriptors, which account for the observed changes in the evaluated activity, were defined. The methodology presented in this research holds potential for identifying novel agents for atherosclerosis treatment by targeting sphingomyelin synthase 2. [ABSTRACT FROM AUTHOR]

The structures of 16 phosphane chalcogenide complexes of gold(I) halides, with the general formula R¹ 3-nR² nPEAuX (R¹ = t-butyl; R² = isopropyl; n = 0 to 3; E = S or Se; X = Cl, Br or I), are presented. The eight possible chlorido derivatives are: 1a, n = 3, E = S; 2a, n = 2, E = S; 3a, n = 1, E = S; 4a, n = 0, E = S; 5a, n = 3, E = Se; 6a, n = 2, E = Se; 7a, n = 1, E = Se; and 8a, n = 0, E = Se, and the corresponding bromido derivatives are 1b-8b in the same order. However, 2a and 2b were badly disordered and 8a was not obtained. The iodido derivatives are 2c, 6c and 7c (numbered as for the series a and b). All structures are solventfree and all have Z' = 1 except for 6b and 6c (Z' = 2). All molecules show the expected linear geometry at gold and approximately tetrahedral angles P--E--Au. The presence of bulky ligands forces some short intramolecular contacts, in particular H. . .Au and H. . .E. The Au--E bond lengths have a slight but consistent tendency to be longer when trans to a softer X ligand, and vice versa. The five compounds 1a, 5a, 6a, 1b and 5b form an isotypic set, despite the different alkyl groups in 6a. Compounds 3a/3b, 4b/8b and 6b/6c form isotypic pairs. The crystal packing can be analysed in terms of various types of secondary interactions, of which the most frequent are 'weak' hydrogen bonds from methine hydrogen atoms to the halogenido ligands. For the structure type 1a, H. . .X and H. . .E contacts combine to form a layer structure. For 3a/3b, the packing is almost featureless, but can be described in terms of a double-layer structure involving borderline H. . .Cl/Br and H. . .S contacts. In 4a and 4b/8b, which lack methine groups, Cmethyl--H. . .X contacts combine to form layer structures. In 7a/7b, short C--H. . .X interactions form chains of molecules that are further linked by association of short Au. . .Se contacts to form a layer structure. The packing of compound 6b/6c can conveniently be analysed for each independent molecule separately, because they occupy different regions of the cell. Molecule 1 forms chains in which the molecules are linked by a Cmethine. . .Au contact. The molecules 2 associate via a short Se. . .Se contact and a short H. . .X contact to form a layer structure. The packing of compound 2c can be described in terms of two short Cmethine--H. . .I contacts, which combine to form a corrugated ribbon structure. Compound 7c is the only compound in this paper to feature Au. . .Au contacts, which lead to twofold-symmetric dimers. Apart from this, the packing is almost featureless, consisting of layers with only translation symmetry except for two very borderline Au. . .H contacts. [ABSTRACT FROM AUTHOR]