Space Environment Research Articles

Online Flow Measurement of Liquid Metal Solutions Based on Impact Force Sequences: Modeling Analysis, Simulation, and Validation of Experimental Results.

Aiming at the existing high-temperature liquid metal flow online accurate measurement by the metal melt characteristics, installation space, and high-temperature environment adaptability limitations, this paper innovatively puts forward a soft measurement method based on the impact force generated in the fluid flow process as an observational variable series. Fluid mechanics theory and simulation software are used to analyze and verify the feasibility of the impact force as an observable variable to measure the flow rate, followed by the construction of the CNN-LSTM-CNN-Double (CLCD) flow measurement model of impact force and flow rate based on the parameters of the learning rate and the number of training times, and finally the construction of a test platform for the flow measurement, and the validity of the method is verified through actual operation.

A Virtual Solar Wind Monitor at Mars With Uncertainty Quantification Using Gaussian Processes

AbstractSingle spacecraft missions do not measure the pristine solar wind continuously because of the spacecrafts' orbital trajectory. The infrequent spatiotemporal cadence of measurement fundamentally limits conclusions about solar wind‐magnetosphere coupling throughout the solar system. At Mars, such single spacecraft missions result in limitations for assessing the solar wind's role in causing lower altitude observations, such as auroral dynamics or atmospheric loss. In this work, we detail the development of a virtual solar wind monitor from the Mars Atmosphere and Volatile Evolution (MAVEN) mission; a single spacecraft. This virtual solar wind monitor provides a continuous estimate of the solar wind upstream from Mars with uncertainties. We specifically employ Gaussian process regression to estimate the upstream solar wind and uncertainty estimations that scale with the data sparsity of our real observations. This proxy enables continuous solar wind estimation at Mars with representative uncertainties for the majority of the time since late 2014. We conclude by discussing suggested uses of this virtual solar wind monitor for statistical studies of the Mars space environment and heliosphere.

Optical Thin Films in Space Environment: Investigation of Proton Irradiation Damage.

The present work reports a systematic study of the potential degradation of metals and dielectric thin films in different space environments. The mono- and bilayers selected are made of materials commonly used for the realization of optical components, such as reflective mirrors or building blocks of interferential filters. More than 400 samples were fabricated and irradiated with protons at different energies on ground-based facilities. The fluences were selected as a result of simulations of the doses delivered within a long-term space mission considering different orbits (Sun close, Jovian, and Geostationary orbits). In order to stress the samples at different depths and layer interfaces, experiments were carried out with a range of proton energies within 1 and 10 MeV values. An estimate of a safe maximum fluence has been provided for each type of sample at each energy. The damage mechanism, when present, has been investigated with different optical and structural techniques.

A Systematic Review of Light Therapy on Mental Health on and Beyond Earth

Light can influence human emotional well-being, sleep quality, and circadian rhythms. The application of these qualities in a therapeutic context is currently being explored. Research has been conducted into the effects of light therapy on wound healing, sleep enhancement, stress management, and the improvement of depressive symptoms. Despite the extensive amount of studies in this field, a satisfactory framework for categorizing light therapies has yet to be developed. To address this problem, our research team proposes to categorize light therapy by wavelength (color). The benefit of this categorization is that, while therapeutic applications may evolve, the fundamental properties of light colors remain constant. Categorizing by color supports scientific innovation and maintains consistent categories even as new research emerges. On the other hand, light therapy’s potential is undermined. Light therapy is characterized by its affordability, durability, consistency, and minimal side effects. While light therapy is interchangeable with other therapeutic methods in common scenarios, it is specifically suited for environments where all those attributes are essential. Space missions represent one such environment. Space exploration is a major frontier for humanity, yet the mental health and living conditions of astronauts have received limited attention. Space missions present unique environmental challenges to astronauts due to altered light exposure, high-pressure, and isolated living environments. These environmental problems need to be addressed, but the resource-scarce space environment requires a reliable and durable solution. Light therapy’s advantages align well with these constraints. Moreover, its ability to address issues such as disrupted circadian rhythms and psychological stress caused by space environmental problems renders it an optimal intervention for space exploration. This article will examine the therapeutic effects of light therapy, with a particular focus on the ways in which different light colors address various health issues and recent discoveries. The potential of light therapy will be demonstrated through the use of space missions as an illustrative example. Additionally, we will briefly discuss future research directions for light therapy. Our primary objective is to establish an intuitive and stable categorization of light therapy. We will examine the potential of light therapy in unique environments, such as space missions, and discuss how it can address common symptoms experienced during these missions. Our ultimate goal is to fully realize the potential of light therapy in tailored environments and inspire the discovery of other scenarios where light therapy can be equally effective.

Guide Field Dependence of Energy Conversion and Magnetic Topologies in Reconnection Turbulent Outflow

AbstractEnergy conversion between the fields and the particles occurs through various physical processes within space environments. Magnetic reconnection stands out as one such process capable of rapidly and massively releasing energy. The high‐speed outflow jets produced by reconnection can induce turbulence characterized by intermittent structures. In this study, we investigate the impact of guide field on the energy conversion associated with the magnetic topologies within these structures during reconnection. Utilizing both particle‐in‐cell simulations and observations from the Magnetospheric Multiscale mission, our findings suggest that a larger guide field present during reconnection leads to increased energy conversion as well as the generation of O‐type topology structures within the turbulent outflow. Our results provide significant evidence on the relationships between energy conversion and magnetic topologies within turbulent outflow of reconnection and the guide field conditions.

Exoplanet Aeronomy: A Case Study of WASP-69 b’s Variable Thermosphere

Aeronomy, the study of Earth’s upper atmosphere and its interaction with the local space environment, has long traced changes in the thermospheres of Earth and other solar system planets to solar variability in the X-ray and extreme-ultraviolet (collectively, XUV) bands. Extending comparative aeronomy to the short-period extrasolar planets may illuminate whether stellar XUV irradiation powers atmospheric outflows that change planetary radii on astronomical timescales. In recent years, near-IR transit spectroscopy of metastable Hei has been a prolific tracer of high-altitude planetary gas. We present a case study of exoplanet aeronomy using metastable Hei transit observations from Palomar Observatory's Wide Field InfraRed Camera and follow-up high-energy data from the Neil Gehrels Swift Observatory that were taken within 1 month of the WASP-69 system, a K-type main-sequence star with a well-studied hot Jupiter companion. Supplemented by archival data, we find that WASP-69's X-ray flux in 2023 was less than 50% of what was recorded in 2016 and that the metastable Hei absorption from WASP-69 b was lower in 2023 versus past epochs from 2017 to 2019. Via atmospheric modeling, we show that this time-variable metastable Hei signal is in the expected direction given the observed change in stellar XUV, possibly stemming from WASP-69's magnetic activity cycle. Our results underscore the ability of multiepoch, multiwavelength observations to paint a cohesive picture of the interaction between an exoplanet’s atmosphere and its host star.

Gate breakdown induced stuck bits in sub-20 nm FinFET SRAM

This paper discusses the stuck bits induced by the gate breakdown of PMOS in the sub-20 nm FinFET static random access memory (SRAM) device. After the heavy-ion experiment, several stuck bits are in the FinFET SRAM matrix, which cannot be set or reset. To investigate the factors that caused the stuck bit, we perform the electrical failure analysis (EFA) to measure the electric characteristics of the transistors in the stuck bits and normal cells separately. The measurement results show a clear gate breakdown at the PMOS pull-up (PPU) transistor in all of the measured SRAM cells. Meanwhile, the SPICE simulation based on the EFA results verifies the impact of the damaged PPU. Finally, considering all of the phenomena, the charge deposition from single events is the major mechanism that causes the stuck bits in FinFET SRAM. The experiment results alert a potential gate breakdown risk in the ultra-high-density FinFET SRAM applied in the space environment.

Centimeter-level 2D ultra-small interdigital sensor for ESD detection of spacecraft

The spacecraft in geosynchronous orbit interacts with the space plasma environment, which is prone to electrostatic discharge and affects the safe operation of the spacecraft. In order to realize simple, accurate and reliable electrostatic discharge detection in space environment, based on the energy spectrum characteristics of spacecraft electrostatic discharge electromagnetic radiation electromagnetic pulse and the electromagnetic pulse sensing principle of interdigital electrode, a centimeter-level two-dimensional planar ultra-small interdigital sensor with a size of only 4 cm × 3 cm × 0.01 cm is developed. The impedance matching circuit is established to greatly improve the transmission efficiency of electromagnetic pulse, which is 59.34 % higher than that before the matching circuit is added. Finally, a spacecraft vacuum electrostatic discharge simulation experiment platform is built to test the frequency response characteristics of the sensor. The results show that the frequency response characteristics of the electromagnetic pulse signal perceived by the sensor developed in this paper are consistent with the main frequency characteristics of the spacecraft electrostatic discharge radiation electromagnetic pulse energy spectrum, which can be used for spacecraft electrostatic discharge detection in space environment.

Numerical study on the gas-solid diffusion characteristics of airflow and dust particles in metal mine blasting excavation under three hybrid ventilation modes

Dust pollution has long been a challenge in the blasting excavation of underground metal mines, and uncontrolled diffusion of dust particles seriously endangers the health and safety of workers as well as the environment in underground space. Most existing research on dust diffusion focuses on fully mechanized coal mining face or borehole drilling, where the dust source emission characteristics differ significantly from metal mine blasting excavation. Furthermore, it is still unclear how the ventilation modes of Far-Pressing-Far-Absorption (FPFA), Near-Pressing-Far-Absorption (NPFA), and Far-Pressing-Near-Absorption (FPNA) affect the mechanism of dust diffusion in the breathing zone. In this work, gas-solid flow characteristics in a typical metal mine blasting tunnel are numerically studied based on Euler-Lagrange method. The interphase forces between airflow and dust particles are comprehensively modeled, and the particle diffusion effect caused by fluid turbulence is described by the discrete random walk model. Five typical regions for airflow disorder phenomena in the working tunnel are predicted, including the jet development region, the return airflow core region, the airflow reversal region, the airflow recirculation region, and the secondary flow region. The spatial distribution of dust exhibits nonuniform characteristics under turbulent airflow transport. The time results of the monitored dust concentration reveal that the junction of the working tunnel and the return airway is a key area of focus for the prevention and control of dust pollution. Among the three ventilation modes, the Far-Pressing-Near-Absorption (FPNA) ventilation mode has the best dust removal efficiency. The supply vent further from the blasting face allows the jet to fully develop, while the exhaust vent closer to the blasting face allows dust particles to be drawn in and discharged earlier. Under the condition of fixed total power consumption for the supply and exhaust fans, a larger exhaust airflow velocity helps remove dust from the breathing zone.

Developing the age-friendly community parks survey for older adults: Assessing aging environment

Many scholars have developed tools to assess the public green environment and examine the impact of parks on people's health and recreational activities. However, environmental reviews often overlook the vulnerability of older adults, and an age-friendly community parks survey (AF-CPS) is lacking. This study developed a comprehensive assessment system, the AF-CPS. The research process was divided into three phases covering eight dimensions: a. humanistic environment (e.g., participation in the green space environment and in cultural exchange); b. infrastructure (e.g., edutainment, medical, and sports facilities); c. recreation comfort (e.g., atmospheric conditions, noise environment, trail comfortableness); d. site planning (e.g., spatial layout, activity space diversity); e. environmental quality (e.g., plant richness, latitude of vision); f. barrier-free environment (e.g., barrier-free site identification，barrier-free service facilities and barrier-free functional facilities); g. environmental maintenance (e.g., participation in building policy decisions, landscape maintenance management); and h. security management. The establishment of the evaluation system was based on a literature review. During the verification and modification of the model, an on-site investigation and questionnaire survey were conducted with elderly individuals (60+) in a community park to identify an evaluation system that can be used as a research tool to promote the construction and renewal of an aging-friendly environment in community parks.

Fast development and validation of a Sensing Suite system for CubeSats

Educational CubeSats still remain valuable hands-on practice activity in an academic environment and provide effective and innovative solutions from technical and management points of view. Fast delivery and low cost is the paradigm driving such projects. Contemporary, the simplicity of the solutions has to match with reliability to guarantee the success of the on orbit operations. The present paper shows the entire life cycle of a Sensing Suite System suitable as scientific data collector within a CubeSat, developed in less than four months from the conceptual design to the delivery and reaching the orbit in less than six months. Technical solutions for hardware and software development and test and management good practices are provided. Circuits details to withstand and/or tolerate the space environment and data handling to maximize the number of data and measurements gathered onboard are explained. The use of breadboards and flat-sat arrangements support both the design and verification of the protoflight comprising the schedule and increasing the confidence level on the goodness of the entire solution. The reliability of the design is proven through the entire assembly, integration and verification campaign and validated by the data sent by the satellite during the operative mission.

Vibration isolation platform for large-amplitude-low-frequency excitation by parallel-stack-assembly design of Miura origamis

To achieve an ultralow-frequency vibration isolation platform for simulation of space environment, suspension method is always utilized. However, the natural frequency of the suspension system is inversely proportional to the length of the suspension cable. In order to further reduce the dynamic stiffness, compress the suspension area, and achieve vibration isolation for wide-amplitude excitations, we propose parallel-stack-assembly (PSA) design principle for Origamis to construct absolute zero-stiffness for required intervals. The dynamic model for wide-range amplitude and deformation, design criteria for required low-frequency large-amplitude isolation effectiveness, and analysis for nonlinear vibration isolation property are given. Finally, the prototype is carried out to validate the theoretical analysis and design principle. The PSA design principle of Origamis creates the large-amplitude and ultralow-frequency isolation property, and, the study expands the applicability of isolators for low-frequency excitation with large amplitude for the systems in aviation, marine etc.

Green spaces contribute to structural resilience of the gut microbiota in urban mammals

The gut microbiome of wild animals is subject to various environmental influences, including those associated with human-induced alterations to the environment. We investigated how the gut microbiota of a synurbic rodent species, the striped field mouse (Apodemus agrarius), change in cities of varying sizes, seeking the urban microbiota signature for this species. Fecal samples for analysis were collected from animals living in non-urbanized areas and green spaces of different-sized cities (Poland). Metagenomic 16S rRNA gene sequencing and further bioinformatics analyses were conducted. Significant differences in the composition of gut microbiomes among the studied populations were found. However, the observed changes were dependent on local habitat conditions, without strong evidence of a correlation with the size of the urbanized area. The results suggest that ecological detachment from a more natural, non-urban environment does not automatically lead to the development of an “urban microbiome” model in the studied rodent. The exposure to the natural environment in green spaces may serve as a catalyst for microbiome transformations, providing a previously underestimated contribution to the maintenance of native gut microbial communities in urban mammals.

Electron Beams at Europa

AbstractJupiter's moon Europa contains a subsurface ocean whose presence is inferred from magnetic field measurements, the interpretation of which depends on knowledge of Europa's local plasma environment. A recent Juno spacecraft flyby returned new observations of plasma electrons with unprecedented resolution. Specifically, powerful magnetic field‐aligned electron beams were discovered near Europa. These beams, with energies from ∼30 to ∼300 eV, locally enhance electron‐impact‐excited emissions and ionization in Europa's atmosphere by more than a factor three over the local space environment, and are associated with large jumps of the magnetic fields. The beams therefore play an essential role in shaping Europa's plasma and magnetic field environment and thus need to be accounted for electromagnetic sounding of Europa's ocean and plume detection by future missions such as JUICE and Europa Clipper.

The Impact of Meta-Universes on Business Development in Digital Economy

The article systematizes approaches to the definition of meta-universe essence as multi-dimensional spaces, which integrate multitude of virtual words, where digital copies of the real world (including business) are made, where participants can interact with each other and with surrounding objects. It was found out that meta-universes form a key trend in economy development in Russia in general and its certain branches and industries, which could foster productivity improvement and business-process optimization in the digital world. The authors analyzed examples of mixed reality (VR/AR-technologies), blockchain and crypto-currencies in Russia and abroad. Factors affecting the development of meta-universes, such as normative and legal, economic, technological, social were identified. The article enumerates risks and restrictions connected with the development of meta-universe technologies: cyberthreats and risks of big data protection, risks of the absence of common cash unit in meta-universes or rules of converting exchange means in meta-universes in usual exchange means, complexity of financing of developing technological projects due to prolonged market entering, insufficient number of experts in the field of virtual, augmented and mixed reality, blockchain, crypto-currencies, etc. The authors identified specific impact of metauniverses on the development of business in the digital environment (in virtual multi-dimensional spaces of metauniverses the pass-over to new economy of impressions speeds up and new possibilities for distance interaction are formed, the format of training and developing employees is transformed, digital doubles are built by developing accurate virtual copies of business-organizations and others). Final conclusions and recommendations were formulated concerning the necessity of taking into account the impact of normative and legal, economic, technological and social factors on business development in virtual spaces in meta-universes, as well as effective and potential threats and hazards connected with the development of economic activity in virtual spaces in order to realize potential of business in the field of new technological phenomenon of meta-universes.

Thermal comfort investigation of membrane-assisted radiant cooling in outdoor settings

The global warming and urban heat island effect call for mitigation strategies for improving thermal environments in open urban spaces. Radiant cooling can remove heat from the human body via direct thermal radiation, thereby creating the possibility to provide active cooling for people in outdoor environments. While using a transparent membrane, convection energy lost to the ambient airflow can be minimized. However, current research on the thermal comfort of radiant cooling systems is restricted to indoor applications, while outdoor applications remain unclear. To address this need, the study investigated the effect of membrane-assisted asymmetric radiant cooling on people's thermal perception in outdoor environments. A radiant cooling facility in an outdoor setting was built, and its cooling effects were assessed by using 248 human subjects across hot and transitional seasons. It is found that the radiant cooling facility can lower the mean thermal sensation vote (MTSV) by 0.6 to 1.5 units. The degree of cooling depends both on the panel temperature and environmental conditions. At the panel surface temperature of 14.3°C, MTSV was at the neutral zone (-0.5 ≤ MTSV ≤ 0.5) with the environmental UTCI as high as 38.1°C, whereas the thermal sensation of the group without radiant cooling was rated warm to hot. Under this condition, the ambient UTCI scope of no heat stress can be extended by 10.1°C higher. The strongest local cooling sensation appeared in the back, with an average decrease of 1.33 units in MTSV, contributing to lowering the overall thermal sensation of the body. For the first time, it is demonstrated that membrane-assisted radiant cooling panels can effectively improve thermal comfort in open outdoor settings.

China's Ground‐Based Space Environment Monitoring Network—Chinese Meridian Project (CMP)

AbstractMonitoring and investigation of the solar‐terrestrial space environment is a huge challenge for humans in space age. To this end, China has established the Ground‐based Space Environment Monitoring Network, namely Chinese Meridian Project (CMP). The project comprises three major systems: the Space Environment Monitoring System, Data and Communication System, and Scientific Application System. The Space Environment Monitoring System adopts a well‐designed monitoring architecture, known as “One Chain, Three Networks, and Four Focuses,” to achieve stereoscopic and comprehensive monitoring of the entire solar‐terrestrial space. The “One‐Chain” component utilizes optical, radio, interplanetary scintillation, cosmic ray instruments to cover the causal chain of space weather disturbances from the solar surface to near‐Earth space. For the ionosphere, middle and upper atmosphere, and magnetic field, instruments are deployed along longitudes of 120° and 100°E, and latitudes of 30° and 40°N, forming the “Three Networks.” Furthermore, more powerful monitoring facilities or large‐scale instruments have been deployed in four key regions: the high‐latitude polar region, mid‐latitude region in northern China, low‐latitude region at Hainan Island, and the Tibet region. These four regions are crucial for disturbances propagation and evolution, or possess unique geographical and topographical characteristics. The Data and Communication System and Scientific Application System are designed for data collecting, processing, storage, mining, and providing user service based on data acquired by the Space Environment Monitoring System. The data obtained by CMP will be shared with the global scientific community, facilitating enhanced collaboration on space weather and space physics research.

Piezoelectric energy harvesting from the atomic oxygen hypervelocity impact in low Earth orbit

Atomic oxygen (AO) in low Earth orbit (LEO) can cause severe progressive damage to spacecraft orbiting at hypervelocities over 7 km/s; therefore, all space-graded materials need to be qualified for protection against these high energy impacts. Instead of treating AO as a threat, can we use these atomic impacts, which have enough energy to cause material failure, to generate power? Despite its potential, no attempt has yet been made to utilize the hypervelocity impact energy of AO. Thus, we propose a piezoelectric energy harvesting method through the hypervelocity AO impact in LEO. In this study, energy harvesting with various configurations was experimentally demonstrated using a conventional lead zirconate titanate (PZT) ceramic plate under oxygen plasma exposure to simulate AO impact. The average output power density was 4 W/m2 under 1.43 × 1016 atoms/cm2s effective AO flux conditions. Our study provides a new method for generating energy in a space environment with limited energy sources.

Apple Vision Pro’s new technology as a head-mounted perimetry device for glaucoma and other potential applications

Abstract Glaucoma is a leading cause of irreversible blindness worldwide and poses a significant public health challenge. Primary open-angle glaucoma (POAG) is the most common form of glaucoma and is marked by progressive optic nerve damage and peripheral visual field loss. Early detection and management of glaucoma are essential to prevent severe vision impairment. Perimetry measures visual field sensitivity and is a crucial tool for diagnosing and the progression of glaucoma. However, traditional perimetry devices are bulky, expensive, and require specialized settings, thereby limiting their accessibility. Studies indicate the evolving role of portable and home-based visual field testing, where the efficacy of virtual reality (VR) devices such as the VisuALL against traditional perimetry tools. Apple Vision Pro’s integration into glaucoma management could address the limitations of conventional perimetry, and thus making monitoring more feasible and less burdensome. In this manuscript, we explore the potential of Apple Vision Pro’s technology as a head-mounted perimetry device for glaucoma. The Apple Vision Pro headset leverages advances in augmented reality and wearable computing to offer a portable, cost-effective solution for visual field testing. Its compact design enables patients to perform tests at home, thus reducing the need for clinical visits and improving adherence to monitoring protocols. This portability is also particularly beneficial in space environments, such as on the International Space Station, where regular monitoring of visual health of astronauts is critical.

Genetic diversity of SP1 population of space mutagenized Pueraria montana

To explore the mutagenic effect of the space environment on Pueraria montana and select the elite germplasm with good growth conditions and high isoflavone content, this study observed the agronomic traits, determined the flower isoflavone content, and labeled amplified fragment length polymorphism(AFLP) fluorescent molecular markers of 79 P. montana plants exposed to space mutagenesis(SP1 group) and 10 control plants of P. montana(CK group). Excel 2019, SPSS 25.0, NTSYSpc-2.11F, and Popgen 32 were employed to analyze the genetic diversity and perform the cluster analysis. The results showed that the SP1 group presented changed leaf hairy attitude and flower structure and higher CV and H' of quantitative traits than the CK group. The cluster analysis screened out five plants in the SP1 group. Ten P. montana plants in the SP1 group had higher content of 6″-O-xylosyl-tectoridin and tectoridin in the flowers than the control group, with the total content of both exceeding 11%. After clustering, 9 plants in the SP1 group were separated. Nine pairs of polymorphic primers were screened out frrom 64 pairs of primers. A total of 1 620 polymorphic loci were detected, with the average percentage of polymorphic loci(PPL) of 83.33%. The average Nei's gene diversity index(H) and Shannon's information index(I) were 0.192 2 and 0.305 2, respectively. After clustering, 4 plants in the SP1 group were screened out. According to the above results, plants No. 30, No. 66, and No. 89 in the SP1 group were subjected to greater mutagenic effect by the space environment and presented better growth and higher flower isoflavone content. Moreover, plant No. 30 showed the flower structure variation and flower weight two times of that in the CK group. These plants can be used as key materials for the subsequent experiments.