Human deep space exploration is presented with multiple challenges, such as the reliable, efficient and sustainable operation of life support systems. The production and recycling of oxygen, carbon dioxide (CO2) and fuels are hereby key, as a resource resupply will not be possible. Photoelectrochemical (PEC) devices are investigated for the light-assisted production of hydrogen and carbon-based fuels from CO2 within the green energy transition on Earth. Their monolithic design and the sole reliance on solar energy makes them attractive for applications in space. Here, we establish the framework to evaluate PEC device performances on Moon and Mars. We present a refined Martian solar irradiance spectrum and establish the thermodynamic and realistic efficiency limits of solar-driven lunar water-splitting and Martian carbon dioxide reduction (CO2R) devices. Finally, we discuss the technological viability of PEC devices in space by assessing the performance combined with solar concentrator devices and explore their fabrication via in-situ resource utilization. 2873 ncomms Nature Communications Nat Commun Nature Publishing Group PMC10244351 10244351 10244351 37280222 10.1038/s41467-023-38676-2 Assessment of the technological viability of photoelectrochemical devices for oxygen and fuel production on Moon and Mars Ross Byron 1 Haussener Sophia 2 Brinkert Katharina 1 3 ✉ 1 Department of Chemistry, University of Warwick, Coventry, CV4 7AL UK 2 Institute of Mechanical Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland 3 ZARM – Center for Applied Space Technology and Microgravity, University of Bremen, 28359 Bremen, Germany ✉ Corresponding author. Finally, we discuss the technological viability of PEC devices in space by assessing the performance combined with solar concentrator devices and explore their fabrication via in-situ resource utilization. Subject terms: Energy modelling, Theoretical chemistry, Electrocatalysis, Space physics Long-term space missions to the Moon and Mars rely on sunlight as an energy source. Here, authors assess the performance of monolithic photoelectrochemical devices for light-assisted O 2 and fuel production on the Moon and Mars as potential complementary technologies to existing life support systems. The devices require a separate design for each target location, which can result in vastly different optimal configurations. This necessitates modelling the photon distribution on Moon and Mars, the simulation of a new series of standard Martian air mass (MAM) spectra as well as the determination of the irradiance and temperature cycles of the celestial surface 32 . These parameters are then fed into the solar-assisted electrochemical device designs. Moreover, we provide annual fuel and oxygen production rates and discuss the incorporation of solar concentrator technology to realise the technological and economic feasibility of solar-driven lunar water-splitting and Martian CO 2 R. Finally, we provide an overview of the natural abundance of resources on the Moon and Mars for PEC device fabrication via ISRU. Fig. 1 Energy level diagrams. a PEC (photoelectrochemical) energy level diagram, where the device consists of a metal anode and tandem p-n junction photocathode that forms an interface with the electrolyte. b GDE (gas-diffusion electrode)-based CO 2 device energy level diagram, where the device consists of a metal anode and buried p-n tandem semiconductor (SC) junction that forms an interface with the GDE. This brief analysis shows that the development of, e.g., self-cleaning coatings is of uttermost importance not only for the application of PEC devices on the Moon and Mars, but essentially for all solar harvesting technologies. Engineering outlook One technology that could be incorporated with solar-assisted oxygen and fuel production devices on the Moon and Mars is solar concentrators, enabling larger production rates and higher power density devices 62 . Supplementary Table 8 summarises the natural abundance of photoelectrochemically relevant elements as composites of semiconductors and electrocatalysts on Earth, Moon and Mars. It becomes evident that the in-situ utilisation of elements on both, the Moon and Mars, is feasible for the construction of PEC devices. Particularly interesting is the possibility of designing devices with terrestrially precious, but highly efficient electrocatalyst materials such as Pt and Rh, which allows the approach of thermodynamically limiting device efficiencies. Table 4 summarises the optimal bandgaps of PEC devices for solar water-splitting and CO 2 R on Moon and Mars with suggestions for suitable electrocatalysts and semiconductor materials based on the lunar and Martian availability (Supplementary Tables 8 and 9 ). Table 4 Engineering guidelines for realistic solar-assisted oxygen and fuel production devices Model Model ε g Semiconductors Electrocatalysts OER, H 2 /CO 2 R DJ Moon (H 2 The semiconductor column specifies the closest abundant material available on Moon or Mars that can be used for the design with the respective, intrinsic ε g . One can use this table in conjunction with Supplementary Table 8 (natural resource abundances for the Earth, Moon, and Mars) to generate guidelines for an ISRU PEC design. The electrolytes correspond to 1 M H 2 SO 4 (aq) and 1 M KHCO 3 (aq) for water-splitting and CO 2 R, respectively. DJ dual-junction. Solar-driven GDE devices are in these conditions not able to reach their full potential. Further electrochemical CO 2 R research—for terrestrial and space applications—should be directed towards in-depth solar concentrators modelling to raise the photoelectrode/PV output or revisit conventional H-type CO 2 R devices which could be more effective for CO 2 R at low current densities. Nevertheless, from both, experimental and theoretical perspectives, challenges and questions regarding the application of PEC devices on the Moon and Mars remain.

This Perspective explores the synergy between bioinspired technologies for sustainability on Earth and their application in space exploration. We focus on the parallels between the paradigm shift toward sustainable development on our planet and establishing permanent human settlements on Mars and the Moon. Informed by Earth’s ecological and technological progress, which emphasizes the critical need for efficiency and integration with the planet’s metabolic processes, the discussion revolves around the challenges and opportunities in creating self-sustaining communities in space. Specifically, the focus is on the central role that bioinspired materials, particularly bioinspired chitinous materials, will play in developing sustainable manufacturing practices on Earth and in extraterrestrial environments. Considering the development of bioinspired chitinous manufacturing in the last decade, we argue that we are witnessing the birth of a new manufacturing paradigm embracing efficiency, resilience, and ecological cycles inspired by biological systems, which will be essential for sustainable living on Earth and advancing a new age of space exploration.

Spaceflight Standard Measures is an integrated research study designed to characterize how spaceflight affects the health and performance of astronauts. Standardizing the research methods allows for robust monitoring of individuals and allows comparison between crewmembers of different missions of various durations. This manuscript reviews the objectives of the Spaceflight Standard Measures project, and details how each disciplinary component is used to monitor spaceflight-induced human risks. It also covers the timeline of data collection, the methods used to analyze the data, and the process for requesting access to the data. With the impending return to lunar operations and exploration of deep space, an urgent need exists for high-quality, multidisciplinary investigations to inform programmatic and operational decisions. The Spaceflight Standard Measures model provides a standardized, flexible research approach, fostering collaboration across agencies to create a strong evidence base that can be used to safely advance human spaceflight into multiplanetary exploration.

Space exploration has progressed significantly since the mid-20th century, and recent technological advancements, along with the emergence of commercial space travel, have led to substantial leaps in planning for future space missions. The largest planned upcoming mission is the Artemis program, supported by NASA and the international Artemis Accords, which aims to create the first permanent human presence on the Moon and in deep space (the Moon to Mars architecture). Although human psychology and team science have been crucial for the success of past space missions, from the Apollo program an The largest planned upcoming mission is the Artemis program, supported by NASA and the international Artemis Accords, which aims to create the first permanent human presence on the Moon and in deep space (the Moon to Mars architecture). Although human psychology and team science have been crucial for the success of past space missions, from the Apollo program and Skylab to the Space Shuttle (STS) and the International Space Station (ISS), human factors and social behavior will become even more ubiquitous and essential for space missions in the new era of commercial space. Introduction From its early crewed spaceflights in the 1960s, beginning with the Mercury-Atlas 6 mission (1962) and culminating in the first crewed flight beyond Earth orbit during Apollo 8 (1968), NASA advanced the capabilities needed for human space travel, space exploration, and eventual lunar landings through the Apollo program that concluded in 1972 [ 1 ]. The next phase in space settlement and exploration begins with NASA’s Artemis campaign, which involves a multinational effort to establish a long-term human presence on the Moon and prepares for future crewed missions to Mars. Grounded in the Artemis Accords established in 2020 [ 3 ] and in compliance with the Outer Space Treaty of 1967 [ 4 ], countries and corporations worldwide agree to a set of common principles for the governance of civil exploration and the use of outer space for the benefit of all humankind. The Artemis program includes a series of missions, which started with the uncrewed test flight of the Space Launch System (SLS) rocket and the Orion spacecraft around the Moon in 2022 (Artemis I). Artemis II is scheduled to launch in 2026 and will involve a four-person crewed test flight to 8,889 kilometers (km) beyond the Moon – the farthest humans have ever traveled in space. Afterward, Artemis III is expected to result in the first lunar landing by a human since Apollo 17 in 1972, and the first one at the lunar south pole [ 5 ]. While engineering and technology innovation is necessary for space missions, understanding human and operational dynamics is also crucial for mission success [ 6 ]. This is particularly important if the objective is to establish a long-term presence on the Moon. Human exploration and operations on the Moon can be viewed from a complex systems perspective. It entails heterogeneous agents making decisions and exhibiting behavior while interacting with one another and their environment [ 7 ]. Life support systems, power generators, local resource production (i.e., air, water, food), and other essential infrastructure are in place to support ongoing missions. Nuclear generators (e.g., Perseverance power source – the first automated rover currently operating on Mars Jezero crater to use nuclear power instead of solar power, with an estimated energy life of 14 Earth years that is not impacted by surface conditions such as dust storms) are installed in the Moon Base and have provided a steady source of electricity for several years [ 21 ]. Model description. The purpose of the Lunar Base ABM is to provide insight into the human and operational dynamics in extreme environments. The approach utilizes NASA’s human factors and behavioral research, which emphasizes teamwork and psychological resilience, to simulate how astronauts can interact with one another to accomplish tasks and sustain operations on the Moon. Each Agent_Astronaut is designed with a set of attributes, including health, skills, and personality traits, that enable mission planners to simulate the complexities of team dynamics. First, the model does not include physiological effects that astronauts experience during typical space missions. As the mission duration increases pass the three month baseline, the physical conditions of the human body become more stressed due to the influence of extreme environmental and psychological factors. Second, the model does not incorporate communication delays between the Earth, Moon Base, and Gateway that is known to increase operational stresses and can have a negative impact to task performance and emotional health. Our model is not only a benchmark for human space missions (currently focused on the Moon), but represents also an interesting case of emergence in highly controlled and designed top-down phenomena, that warrants further methodological exploration. Conclusion NASA is planning to conduct several crewed missions to the Moon (i.e., Artemis III, IV and V) that will send the first humans to explore the region near the Lunar South Pole and put the Gateway space station in lunar orbit, in the late 2020s or early 2030s, which are necessary stages to establish a human presence on the Moon. The rest of the phrase is fine. I suggest: "While engineering and technology innovation is necessary for space missions, understanding human and operational dynamics is crucial for mission success. Even more so if the objective is to establish long term presence on the Moon." Page 2, line 34, The authors mention NASA's human factors and behavioral research. Is there a reference(s) to this research? I would like to know which specific research is this model based on. This is also necessary for verification and reproduction of the method. Page 3, line 49. The integration of human behavioral modeling,particularly coping capacity, tension, and

<h4>Introduction</h4>Human space exploration is progressing into an unprecedented era characterized by extended-duration missions, the establishment of permanent lunar bases, and planned crewed voyages to Mars. These activities introduce important physiological challenges, primarily driven by exposure to altered gravity environments. Microgravity disrupts vestibular input, generating sensory conflicts that impair spatial orientation, motor coordination, and cognitive performance. Although adaptation to such conditions involves neuroplasticity, the precise neural mechanisms underlying altered gravity exposure remain unclear.<h4>Methods</h4>To address this knowledge gap, we performed a coordinate-based meta-analysis of 15 neuroimaging studies examining functional brain changes associated with spaceflight and validated ground-based analogs. Activation likelihood estimation (ALE) was used to identify convergent patterns of brain activity across studies.<h4>Results</h4>The analysis revealed a predominantly right-lateralized network centred on primary sensorimotor cortices, including the precentral and postcentral gyri, as well as the insula and opercular cortex.<h4>Discussion</h4>These findings suggest that alterations in brain dynamics reflect neuroplastic adaptations to the absence or modification of gravitational signals, supporting the recalibration of internal models that predict and compensate for gravity's influence on perception and motor behaviour. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) . The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. Abstract Introduction Human space exploration is progressing into an unprecedented era characterized by extended-duration missions, the establishment of permanent lunar bases, and planned crewed voyages to Mars. Keywords: altered gravity, brain connectivity, fMRI, galvanic vestibular stimulation, neuroimaging, parabolic flight, space analogs, spaceflight status released display-pdf yes is-olf no is-manuscript no is-preprint no is-journal-matter no is-scanned no is-retracted no Received 2025 Nov 17; Revised 2026 Apr 4; Accepted 2026 Apr 7; Collection date 2026. Introduction Since Neil Armstrong first stepped onto the lunar surface, human space exploration has captured the imagination of scientists, policymakers, and the public alike. What began as a race between nations has evolved into a global scientific and technological pursuit, pushing the boundaries of what humans can achieve beyond Earth. Today, we are witnessing a new phase in space exploration: one marked by plans for long-duration missions, permanent lunar bases, commercial spaceflight, and eventual crewed missions to Mars. These developments are extending humanity’s reach beyond Earth while presenting increasingly complex challenges for human physiological resilience, adaptation and survival. Crews embarking on such missions face multiple environmental hazards, with gravitational variation among the most critical. These range from prolonged microgravity, brief periods of hypergravity during launch and landing, to partial gravity on the Moon or other planetary bodies. The vestibular system is distinguished by its unique neuroanatomical organization. Unlike other sensory modalities, no single, unimodal primary vestibular cortex has been identified in the mammalian brain ( Angelaki and Cullen, 2008 ). Instead, vestibular signals are processed across a widespread network of cortical and subcortical regions. Electrophysiological studies in non-human primates have pinpointed the Parieto-Insular Vestibular Cortex (PIVC) as a central hub within this distributed vestibular network ( Guldin and Grüsser, 1998 ). In humans, functional neuroimaging studies have demonstrated that the homologous vestibular network involves multiple cortical areas, including the posterior parietal operculum, secondary somatosensory cortex, inferior parietal cortex, superior temporal cortex, posterior insula, and premotor cortex ( Bottini et al., 1994 , 1995 ; Dieterich and Brandt, 2015 ; Eickhoff et al., 2006 ; Zu Eulenburg et al., 2012 ). Vestibular information is integrated with visual, somatosensory, proprioceptive, and visceral inputs within this widespread multisensory network. These vestibular-multisensory processes enable the brain to generate coherent spatial representations necessary for effective sensorimotor function and environmental interaction. Humans are exceptionally adapted to Earth’s gravity. For instance, we can accurately predict the acceleration of falling objects even with incomplete visual information ( Zago et al., 2004 ), and our motor behaviors, such as reaching, grasping, and catching, are finely tuned to counteract terrestrial gravitational force ( Lacquaniti et al., 2013 ; Monache et al., 2019 ). Further, this right-hemisphere predominance resonates with clinical observations where lesions affecting right-hemisphere vestibular areas lead to more pronounced deficits in spatial orientation and perception compared to similar left-hemisphere damage ( Dieterich and Brandt, 2015 ). Limitations of the present work should be acknowledged. Methodologically, the included studies were characterized by consistently small sample sizes, reflecting the inherent logistical and ethical constraints of research in spaceflight and analog environments. The limitations identified in the present work also reflect broader challenges in the study of the human brain under altered gravity. Small sample sizes, methodological heterogeneity, and diverse gravitational conditions are not unique to our meta-analysis but characterize much of the field, limiting