The International Space Station (ISS) is a $100 billion epicenter of human activity in the vacuum of space, displaying mankind\'s collective endeavor to explore the cosmic frontier. Even within the marvels of technological sophistication aboard the ISS, the human eye remains a highly vulnerable structure. In the absence of multiple layers of protection and risk assessments, crewmembers would face a substantial increase in vulnerability to ocular injury. Aside from stringent preflight screening criteria for astronauts, the ISS is equipped with ophthalmic medications, environmental control and life support systems (e.g., humidity regulation, carbon dioxide removal, pressurized device regulators), and radiation protection to reduce ocular injury. Moreover, additional countermeasures are currently being developed to mitigate the effects of spaceflight-associated neuro-ocular syndrome (SANS) and lunar dust toxicity for the Artemis Program missions. The success of future endeavors hinges not only on continued technological innovation, but also respecting the intricate interplay between human physiology and the extraterrestrial environments. Establishing habitations on the Moon and Mars, as well as NASA\'s Gateway Program (humanity\'s first space station around the Moon), will introduce a new set of challenges, underscoring the necessity for continuous insights into ocular health in space. We discuss the safety protocols, precautions, and countermeasures implemented on the ISS to prevent ocular injury - an aspect often overshadowed by the grandeur of space exploration.

Dry eye syndrome (DES) poses a significant challenge for astronauts during space missions, with reports indicating up to 30% of International Space Station (ISS) crew members. The microgravity environment of space alters fluid dynamics, affecting distribution of fluids on the surface of the eye as well as inducing cephalad fluid shifts that can alter tear drainage. Chronic and persistent DES not only impairs visual function, but also compromises the removal of debris, a heightened risk for corneal abrasions in the microgravity environment. Despite the availability of artificial tears on the ISS, the efficacy is challenged by altered fluid dynamics within the bottle and risks of contamination, thereby exacerbating the potential for corneal abrasions. In light of these challenges, there is a pressing need for innovative approaches to address DES in astronauts. Neurostimulation has emerged as a promising technology countermeasure for DES in spaceflight. By leveraging electrical signals to modulate neural function, neurostimulation offers a novel therapeutic avenue for managing DES symptoms. In this paper, we will explore the risk factors and current treatment modalities for DES, highlighting the limitations of existing approaches. Furthermore, we will delve into the novelty and potential of neurostimulation as a countermeasure for DES in future long-duration missions, including those to the Moon and Mars.

The translaminar pressure gradient (TLPG) refers to two forces at the lamina cribosa of the optic nerve: the anteriorly acting intracranial pressure (ICP), and posteriorly-acting intraocular pressure (IOP). It has been proposed that controlling the translaminar pressure gradient at regular intervals may preserve the optic nerve and slow the course of glaucoma. The precisional modulation of this TLPG is a recently introduced concept that may play a role in the treatment of ophthalmic diseases such as glaucoma. In this manuscript, we review the applications of pressurized goggles on ophthalmic diseases. We also elaborate upon current investigations in modulation of the TLPG including goggles and the multi-pressure dial goggle. We discuss future research directions for ophthalmic diseases including spaceflight associated neuro-ocular syndrome (SANS), a large physiological barrier to future long-duration spaceflight.

Spaceflight associated neuro-ocular syndrome (SANS) is a collection of distinct findings seen in some astronauts following prolonged spaceflight and is characterized by: optic disc edema, globe flattening, and choroidal folds. In this manuscript, we describe the potential mechanisms linking anemia and SANS. Future research aimed at understanding the relationship between these conditions may help to develop countermeasures and mitigation efforts for SANS.

Astronauts are exposed to an austere and constantly changing environment during space travel. To respond to these rapid environmental changes, high levels of dynamic visual acuity (DVA) are required. DVA is the ability to visualize objects that are in motion, or with head movement and has previously been shown to decrease significantly following spaceflight. Decreased DVA can potentially impact astronauts while performing mission critical tasks and drive space motion sickness. In this paper, we suggest that DVA assessment during spaceflight and during G-transitions should be considered to help further understand the vestibulo-ocular impacts of interplanetary spaceflight and ensure mission performance including potential manned missions to Mars.

OBJECTIVE: This paper surveys the existing literature surrounding problem-solving and team dynamics in complex and unpredictable scenarios, and evaluates the applicability of studying Earth-based construction teams to identify training needs for Lunar construction crews.
BACKGROUND: Lunar and other space exploration construction crews will work in extreme environments and face unpredictable challenges, necessitating real-time problem-solving to address unexpected contingencies. This work will require coordination with Mission Control and autonomous assistants, so crew training must account for multi-agent, distributed teamwork.
METHODS: A narrative literature review identified processes, attributes, and skills necessary for the success of Lunar construction teams. We summarized relevant frameworks and synthesized collective findings into over-arching trends and remaining research gaps.
RESULTS: While significant literature exists surrounding team performance, very little systematic inquiry has been done with a focus on Lunar construction crews and operations, particularly with respect to dynamic problem-solving and team-based decision-making. Established and standardized metrics for evaluating team performance are lacking, resulting in significant variation in reported outcomes between studies.
CONCLUSIONS: Lunar and other space exploration construction teams will need training that focuses on developing the right approach to team-based problem-solving, rather than on preparing response execution for known contingencies. An investigation of successful Earth-based construction crews may facilitate the development of relevant metrics for training future Lunar construction crews.
CONCLUSIONS: Metrics and team training protocols developed for future Lunar construction teams may be adaptable and applicable to a wide range of extreme teams facing uncertain challenges, such as aircrews, surgical teams, first responders, and construction crews.

This project quantifies operationally relevant measures of flight performance and workload in a high-fidelity long-duration spaceflight analog, longitudinally across mission duration, using a portable simulation platform.
Real-time performance measures allow for the objective assessment of task performance and the timely identification of performance degradations.
Measures of flight performance on a piloted lunar lander task were collected on 32 total crewmembers across 8 simulated space missions of 45 days each (623 total sessions).
Mission duration demonstrated a significant effect on measures of flight performance across all campaigns. Flight measures showed a general pattern of peaking in accuracy during the middle-late quartiles of overall mission time, then degrading again towards baseline. On the workload measure, however, a general linear decrease in workload consistent with progressive task learning was observed in both campaigns.
This investigation demonstrated the disruptive effect of time in mission on some, but not all, aspects of task performance. While mission interval differentially impacted measures of flight accuracy, workload, by contrast, seemed to steadily decrease with in-mission time.
While more work is needed, the observed discrepancy between progression of flight performance and workload assessment highlights the importance of sensitive and specific measurement tools for the tracking of distinct performance metrics.

Isolated, confined, extreme (ICE) environments are accompanied by a host of stress-inducing circumstances: operational pressure, interpersonal dynamics, limited communication with friends and family, and environmental hazards. We evaluated the effectiveness of attention-restoration-therapy-based immersive Virtual Reality (VR) in three ICE environments: the Canadian Forces Station-Alert (CFS Alert), the 12-month HI-SEAS IV expedition, and the 8-month HI-SEAS V expedition.
Thirty-one individuals (29 male, 2 female) at CFS Alert, and 12 total crewmembers (7 male, 5 female, six crewmembers per sessions) at HI-SEAS participated. All participants viewed immersive VR scenes, but scene content varied by deployment. Data collection included pre- and post-intervention surveys and semi-structured post-mission interviews. Survey data were analyzed by scene content within each analog using nonparametric approaches.
Acceptability and desirability of the VR content varied significantly by ICE analog, as well as by participants within a given analog. The two initial exploratory protocols enabled a more directed study in HI-SEAS V to identify the importance of differences in scene content.
Use and perceived utility of the VR varied considerably across participants, indicating that psychological support needs to be individualized. Overall, natural scene VR was broadly considered restorative, but after long periods of isolation, dynamic and familiar scenes including those with people were also appealing. Immersive, nature-based VR was highly valued by some, but not all participants, suggesting that this intervention tool holds promise for use in ICE settings but needs to be tailored to the setting and individual.

During spaceflight, astronauts can experience significantly higher levels of hemolysis. With future space missions exposing astronauts to longer periods of microgravity, such as missions to Mars, there will be a need to better understand this phenomenon. We have proposed that retinal fundus photography and deep learning may be utilized to help further understand this microgravity-induced, anemic process for future spaceflight. By utilizing astronaut and terrestrial analog metadata, a foundation can be built to develop an algorithm that allows for non-invasive retinal imaging to quantify hemoglobin levels and detect anemia during spaceflight. This approach would allow for a non-invasive retinal photograph that can be done frequently during spaceflight as opposed to an invasive blood draw and subsequent tests.

The International Space Station (ISS) has around 3-5 crew members on-board at all times, and they normally stay on the ISS for about 5-7months in duration. Since March 2020, 170 long-duration space missions have occurred on the ISS. Thus, long-duration space missions are an integral part of space exploration and will only continue to expand in duration as missions to the Moon and Mars are on the horizon. However, long-duration space missions present several challenges to human crew members. Most of these challenges have been associated with physiological adaptation to microgravity, including motion sickness, muscle atrophy, and cardiovascular deconditioning. While not as well-studied, another major factor to consider when planning long-duration space missions is the psychological impact of the environment on the astronauts. Astronauts living in space will be unable to access natural landscapes and other environments found to have restorative effects on psychological stress and overall well-being. On top of being unable to access these restorative natural environments, astronauts will also be exposed to the stressful, unfamiliar environment of space. The purpose of this mini-review is to first summarize the literature related to stressors associated with space. Next, an overview of the large breadth of literature on the biophilia hypothesis and restorative environments will be provided, as these may serve as relatively simple and cost-effective solutions to mitigate the stress faced during long-duration space missions. Lastly, considerations related to the design of such environments in a space capsule as well as future directions will be presented.