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NASA NTRS1998

NASA/Mir Phase 1: A Lesson Learned in Long Duration Mission Planning and Operations

The NASA/Mir Phase I Program is a precursor to the assembly and operations of the International Space Station (ISS). The Phase I Program covers a four-year period and encompasses over ten shuttle flights to the Mir, culminating with the flight of STS-91 in June 1998. The Mir-Orbiting Station (Mir-OS) provides an excellent environment, both onboard and on the ground, for learning and studying the characteristics associated with crew-tended operations on long duration missions. By the end of the Phase I program, NASA astronauts will have accumulated over two years of continuous operations experience working and living onboard the Mir-OS. Ground controllers, working in Russia and at remote sites in the United States, will have gained valuable experience in the generation, maintenance, and coordination of the information and products required to support the long duration crew members onboard the Mir-OS. The experience gained by the crew and ground support personnel in the area of long duration mission operations has resulted in a number of factors that need to be considered in the definition and implementation of the processes and products for the ISS. While there are many areas in which experience has been gained, this paper focuses on the lessons learned regarding the level of detail and flexibility of crew timelines. Provided in this paper is an overview of the characteristics associated with long duration mission timeline development and execution, a summary of applicable lessons learned identified and documented through participation in the NASA/Mir Phase I Program, a detailed discussion of "Gross Timelines" as implementation which addresses the lessons learned. Also discussed are the challenges that must be overcome in getting the ISS program to recognize, evaluate, and learn from the crew and ground controller experience gained through participation in the NASA/Mir Phase I Program.

Hagopian, Jeff↗

NASA NTRS2006

Development Overview of the Revised NASA Ultra Long Duration Balloon

The development of the National Aeronautics and Space Administration s (NASA) Ultra Long Duration Balloon (ULDB) has made significant strides in addressing the deployment issues experienced in the scaling up of the balloon structure. This paper concentrates on the super-pressure balloon developments that have been, and are currently being planned by the NASA Balloon Program Office at Goddard Space Flight Center s Wallops Flight Facility. The goal of the NASA ULDB development project is to attempt to extend the potential flight durations for large scientific balloon payloads. A summary of the February 2005 test flight from Ft. Sumner, New Mexico will be presented. This test flight spurred a number of investigations and advancements for this project. The development path has pursued some new approaches in the design, analysis, and testing of the balloons. New issues have been ideEti6ed throu& both analysis md testing. These have been addressed in the design stage before the next balloon construction was begun. This paper will give an overview of the recent history for this effort and the development approach pursued for ULDB. A description of the balloon design, including the modifications made as a result of the lessons learned, will be presented. Areas to be presented include the design approach, deployment issues that have been encountered and the proposed solutions, ground testing, photogrammetry, and an analysis overview. Test flight planning and considerations will be presented including test flight safety. An extended duration test flight of the National Aeronautics and Space Administration s Ultra Long Duration Balloon is planned for the May/June 2006 time frame. This flight is expected to fly from Sweden to either Canada or Alaska. Preliminary results of this flight will be presented as available. Future plans for both ground testing and additional test flights will also be presented. Goals of the future test flights, which are staged in increments of increasing suspended load and altitude, will be presented. This will include the projected balloon volumes, payload capabilities, test flight locations, and proposed flight schedule.

Cathey, H. M.↗

NASA NTRS2007

Immune Dysregulation Following Short versus Long Duration Space Flight

Immune system dysregulation has been demonstrated to occur during spaceflight and has the potential to cause serious health risks to crewmembers participating in exploration-class missions. A comprehensive immune assessment was recently performed on 13 short duration Space Shuttle crewmembers and 8 long duration International Space Station (ISS) crewmembers. Statistically significant post-flight phenotype alterations (as compared to pre-flight baseline) for the Shuttle crewmembers included: granulocytosis, increased percentage of B cells, reduced percentage of NK cells, elevated CD4/CD8 ratio, elevated levels of memory CD4+ T cells, and a CD8+ T cell shift to a less differentiated state. For the Shuttle crewmembers, T cell function was surprisingly elevated post-flight, among both the CD4+ and CD8+ subsets. This is likely an acute stress response in less-deconditioned crewmembers. The percentage of CD4+/IL-2+, CD4+/IFNg+ and CD8+/IFNg+ T cells were all decreased at landing. Culture secreted IFNg production was significantly decreased at landing, whereas production of Th2 cytokines was largely unchanged. It was found that the IFNg:IL-10 ratio was obviously declined in the Shuttle crewmembers immediately post-flight. A similar pattern of alterations were observed for the long duration ISS crewmembers. In contrast to Shuttle crewmembers, the ISS crewmembers demonstrated a dramatic reduction in T cell function immediately post-flight. This may be related to the effect of acute landing stress in conjunction with prolonged deconditioning associated with extended flight. The reduction in IFNg:IL-10 ratio (Th2 shift) was also observed post-flight in the ISS crewmembers to a much higher degree. These data indicate consistent peripheral phenotype changes and altered cytokine production profiles occur following space travel of both short and long duration.

Crucian, Brian E.↗

NASA NTRS2008

TDR Using Autocorrelation and Varying-Duration Pulses

In an alternative to a prior technique of time-domain-reflectometry (TDR) in which very short excitation pulses are used, the pulses have very short rise and fall times and the pulse duration is varied continuously between a minimum and a maximum value. In both the present and prior techniques, the basic idea is to (1) measure the times between the generation of excitation pulses and the reception of reflections of the pulses as indications of the locations of one or more defects along a cable and (2) measure the amplitudes of the reflections as indication of the magnitudes of the defects. In general, an excitation pulse has a duration T. Each leading and trailing edge of an excitation pulse generates a reflection from a defect, so that a unique pair of reflections is associated with each defect. In the present alternative technique, the processing of the measured reflection signal includes computation of the autocorrelation function R(tau) identical with fx(t)x(t-tau)dt where t is time, x(t) is the measured reflection signal at time t, and taus is the correlation interval. The integration is performed over a measurement time interval short enough to enable identification and location of a defect within the corresponding spatial interval along the cable. Typically, where there is a defect, R(tau) exhibits a negative peak having maximum magnitude for tau in the vicinity of T. This peak can be used as a means of identifying a leading-edge/trailing-edge reflection pair. For a given spatial interval, measurements are made and R(tau) computed, as described above, for pulse durations T ranging from the minimum to the maximum value. The advantage of doing this is that the effective signal-to-noise ratio may be significantly increased over that attainable by use of a fixed pulse duration T.

Lucena, Angel↗

NASA NTRS2002

Long-Duration Space Flight Provokes Pathologic Q-Tc Interval Prolongation

Space flight has a profound influence on the cardiovascular and autonomic nervous systems. Alterations in baroreflex function, plasma catecholamine concentrations, and arterial pressure regulation have been observed. Changes in autonomic regulation of cardiac function may lead to serious rhythm disturbances. In fact, ventricular tachycardia has been reported during long-duration space flight. The study aim was to determine the effects of space flight on cardiac conduction. Methods and Results: Electrocardiograms (ECGs) and serum electrolytes were obtained before and after short-duration (SD) (4-16 days) and long-duration (LD) (4-6 months) missions. Holter recordings were obtained from 3 different subjects before, during and after a 4-month mission. P-R, R-R, and Q-T intervals were measured manually in a random, blinded fashion and Bazzet's formula used to correct the Q-T interval (Q-Tc). Space flight had no clinically significant effect on electrolyte concentrations. P-R and RR intervals were decreased after SD flight (p<0.05) and recovered 3 days after landing. In the same subjects, P-R and Q-Tc intervals were prolonged after LD flight (p<0.01). Clinically significant Q-Tc prolongation (>0.44 sec) occurred during the first month of flight and persisted until 3 days after landing (p<0.01). Conclusions - Space flight alters cardiac conduction with more ominous changes seen with LD missions. Alterations in autonomic tone may explain ECG changes associated with space flight. Primary cardiac changes may also contribute to the conduction changes with LD flight. Q-Tc prolongation may predispose astronauts to ventricular arrhythmias during and after long-duration space flight.

D'Aunno, DOminick S.↗

NASA NTRS2016

Development and Provision of Functional Foods to Promote Health on Long-Duration Space Missions

During long-duration NASA space missions, such as proposed missions to Mars, astronauts may experience negative physiological effects such as bone loss. Functional foods such as high-lycopene, high-flavonoids and high-omega-3 products and fruits and vegetables may mitigate the negative effects of spaceflight on physiological factors including the bone health of crewmembers. Previous studies showed that current ISS provisions provide high-lycopene and high-omega-3 food items but the variety is limited, which could promote menu fatigue. Bioactive compounds can degrade like other chemical compounds and lose functionality. The native concentrations and stability of bioactive compounds have never been determined in spaceflight foods, and adequate information is not available for commercial products for the storage durations required for space exploration (5 years). The purpose of this task is to develop new spaceflight foods that are high in omega-3 fatty acids, lycopene, or flavonoids, identify commercial products with these bioactive compounds that meet spaceflight requirements, and define the stability of these nutrients in storage to enable purposeful functional food incorporation into the space food system. The impact of storage temperature on the stability of lutein, lycopene, beta-carotene, omega-3 fatty acids, phenolics, anthocyanins and sterols is being studied in 12 ISS menu items stored at three different temperatures (4, 21, 35 degree C) over 2 years. Additionally, nutrient and quality stability are being assessed on a larger food set stored at 21 degree C over 2 years that contains twelve newly developed foods, 10 commercial products repackaged to spaceflight requirements, and another 5 current ISS menu items expected to be good sources of omega-3 fatty acids, lycopene, or flavonoids. All items were shipped overnight to the Linus Pauling Institute at Oregon State University (Corvalis, OR) after processing and 1-year of storage and analyzed for bioactive compound concentrations. Sensory evaluation was conducted on the newly developed functional foods and commercial products with untrained panelists (n is greater than or equal to 25) using a 9-point Hedonic scale to test sensory attributes and overall acceptability after processing and 1-year of storage (21 degree C). Repeat nutritional and sensory analyses will be conducted in the same foods after the 2-year storage period is completed. The stability of bioactive compounds in the selected foods was dependent on storage temperature and food matrix. Omega-3 showed excellent stability in the analyzed products after 1-year of storage, regardless of the storage temperature; phenolic compounds also showed good stability. Lycopene was more stable in oil-based products rather than water-based products because of the protection that lipids offer to lycopene molecules. Also, lycopene was more stable in freeze-dried products than in high moisture foods. The 12 newly developed functional foods showed good overall acceptability in sensory attributes after processing (average score 7.2 out of 9.0) and maintained sensory quality through 1-year (21 degree C); the overall acceptability was on average 7.1 after storage. Similar behavior was observed for the 10 commercial products after 1 year. The developed products are good sources of omega-3 (both plant and marine), vegetables (7 vegetable-based products), and good sources of carotenoids, such as the Curry Pumpkin Soup and the Sweet and Savory Kale. Nine of the new products, such as Mango Salad, Pickled Beets, and Braised Red Cabbage, are rich in phenolic compounds. Stability of most of the studied nutrients seems to be adequate after 1-year of storage in most of the tested foods. However, storage temperature of the food must be considered during long-duration space missions to achieve stability of all nutrients. Likewise, more information is needed regarding nutrient retention after 2-years of storage to identify nutritional gaps that may be expected over the 5-year shelf life required for a Mars mission. New developed products will be filling a gap in the current space food system to minimize menu fatigue, provide specific nutrients to reduce the negative effects of long-duration space missions and maintain crew members' health. Information about bioactive compounds in developed products after 1-year and 2-year of storage will provide the knowledge base for further product development.

Bermudez-Aguirre, D.↗

NASA NTRS2017

The Impact of Mission Duration on a Mars Orbital Mission

Performance alone is insufficient to assess the total impact of changing mission parameters on a space mission concept, architecture, or campaign; the benefit, cost, and risk must also be understood. This paper examines the impact to benefit, cost, and risk of changing the total mission duration of a human Mars orbital mission. The changes in the sizing of the crew habitat, including consumables and spares, was assessed as a function of duration, including trades of different life support strategies; this was used to assess the impact on transportation system requirements. The impact to benefit is minimal, while the impact on cost is dominated by the increases in transportation costs to achieve shorter total durations. The risk is expected to be reduced by decreasing total mission duration; however, large uncertainty exists around the magnitude of that reduction.

Arney, Dale↗

NASA NTRS2018

Justification of Crew Function and Function Capability for Long Duration Deep Space Habitation

There are currently no established standards or guidelines that define the functions to be present in habitats for use beyond Low Earth Orbit (LEO), or for the capabilities of those functions. There is limited human experience with long duration space habitation, none of which is beyond LEO. There is significantly less experience with even short duration human habitation beyond LEO. Studies since the Apollo program that have proposed long duration habitats have applied inconsistent functionality, yet these functions have substantial implications for spacecraft mass and volume. There are also numerous aspects of human space flight beyond LEO that have implications for these functions. This paper develops a method for design teams to identify and justify the functions and capabilities to include in long duration habitats intended for use beyond LEO. Finally, human-in-the-loop testing methods are recommended for use in the early spacecraft design stages to ensure that the habitat will successfully provide the intended functions and capabilities.

Howard, Robert L.↗

NASA NTRS2014

Variation in Sleep Duration and Circadian Phase by Duty Start Time Among Short-Haul Commercial Airline Pilots

Prior studies have confirmed that commercial airline pilots experience circadian phase shifts and short sleep duration following travel with layovers in different time zones. Few studies have examined the impact of early and late starts on the sleep and circadian phase of airline pilots who return to their domicile after each duty period. We recruited 44 pilots (4 female) from a short-haul commercial airline to participate in a study examining sleep and circadian phase over four duty schedules (baseline, early starts, mid-day starts, late starts). Each duty schedule was five days long, separated by three rest days. Participants completed the rosters in the same order. Sleep outcomes were estimated using wrist-borne actigraphy (Actiware Software, Respironics, Bend, OR) and daily sleep diaries. Thirteen participants volunteered to collect urine samples for the assessment of 6-sulfatoxymelatonin (aMT6s). Urine samples were collected in four hourly bins during the day and eight-hourly bins during sleep episodes, for 24 hours immediately following each experimental duty schedule. The aMT6s results were fit to a cosine in order to obtain the acrophase to estimate circadian phase. Univariate statistics were calculated for acrophase changes, schedule start times and sleep times. All statistical analyses were computed using SAS software (Cary, IN).The mean duty start times varied as expected (baseline 10:17 [ 3:50], early starts 5:24 [ 0:30], mid-day starts 13:52 [ 1:20], late starts 16:33 [ 1:33]). Actigraphy-derived sleep duration varied between schedule types, with the shortest average sleep durations occurring during the early starts and night duty. Mean circadian phase was similar during each schedule type (baseline 26:14 [ 3:22], early starts 25:29 [2:13], mid-day starts 26:20 [ 3:16], late starts 25:49 [ 4:28]), but there were wide inter-individual differences in phase shifting from the beginning to the end of the study, with phase shifts ranging from a 5.98 hour phase advance to an 11.34 hour phase delay. Our preliminary findings suggest that early and late starts are associated with reduced sleep duration. The dispersion in inter-individual differences in circadian phase across shifting duty schedules should be further evaluated to determine how schedule-induced phase shifts may affect operational performance.

Flynn-Evans, Erin↗

NASA NTRS2019

NASA's Behavioral Health and Performance Services for Long Duration Spaceflight Missions

Goals of the presentation include: Understand how NASA selects astronauts optimally suited for long duration spaceflight missions (missions 30 days or longer). Understand the basics of space station development and long duration spaceflight history, as well as the behavioral challenges associated long duration spaceflight training and missions. Understand how NASA and its international partners (Russia, Europe, Japan, and Canada) provide behavioral health and performance services and countermeasures to astronauts and cosmonauts during long duration spaceflight missions on the International Space Station.

Beven, Gary E.↗

NASA NTRSDate not supplied

Designing Autonomy into Interfaces for Long-Duration Missions

As NASA develops technologies for long-duration crewed missions, we must understand how communication between ground control teams and astronauts differs from the current dynamic to adapt new concepts for long-duration mission operations. Today, ground control teams support astronauts with immediate availability to answer questions, resolve issues, and manage activities. In the near future, however, extended communication delays during long-duration missions will require astronauts to become more autonomous. As many of the responsibilities shift from the ground control teams to the astronauts on-board, the concept of operations must also change from how it functions today. With increased astronaut autonomy, software tools must be developed that enable efficient completion of mission tasks without increased mental workload. Designing software tools to facilitate crew autonomy requires development teams to know which data will enhance quick decision making while providing necessary context for situational awareness of systems being managed on-board. NASA's Autonomous Systems and Operations (ASO) team is presently developing a software interface tool, EXPRESS (EXpedite the PRocessing of Experiments for Space Station) 2.5 to enable a long-duration crew to schedule activities for and operate autonomous systems. This paper describes details of the integrated human factors approach that drove the design of the elements of the software tool, including self-managed scheduling, constraint-driven planning, autonomous system fault recovery, and recommended troubleshooting actions. Additionally, this paper will chronicle ASO modifications of the user interface after the team's first flight demonstration, how it was based on lessons learned during software development, as well as from crew feedback in order to develop the current version which will be demonstrated on ISS in 2021. In the upcoming ISS demonstration, the astronaut crew will be given scenarios for scheduling and operating autonomous system activities, including off-nominal scenarios and autonomous system recoveries. The demonstration of the EXPRESS 2.5 tool is a step towards improved levels of autonomy as our new journeys take us farther into space.

autonomy↗

NASA NTRS2021

Geospatial Cluster Analysis of the State, Duration and Severity of Drought Over Paraíba State, Northeastern Brazil

Droughts threaten water resources, agriculture, socio-economic activities and the population at the global and regional level, so identifying areas with homogeneous drought behaviors is an important consideration in improving the management of water resources. The objective of this study is to identify homogenous zones over Paraíba State in relation to the state, duration and severity of droughts that have occurred over the last 20 years (1998–2017) using hierarchical cluster analysis based on both gauge-measured and Tropical Rainfall Measuring Mission (TRMM) estimated rainfall data (TMPA 3B42). The drought series were calculated using the Standardized Precipitation Index (SPI) based on eight time scales and were grouped according to drought state, duration and severity time series. The integrated results of state, duration and severity of droughts indicate that there is a basis for dividing Paraíba State into two major regions (a) Zone I, formed by Mata Paraibana and Agreste Paraibano, and (b) Zone II, composed by Borborema and Sertão Paraibano. This division is evident when assessing short-term droughts, but in the case of long-term droughts, Paraíba State has a high similarity in terms of drought state, duration, and severity. Factors such as proximity to the ocean, active climatic systems, and the local relief configuration were identified as influencing the drought regime. Finally, it is concluded that TMPA rainfall estimates represent a valuable source of data to regionalize and identify drought patterns over this part of Brazil and that other studies of this type should be carried out to monitor these phenomena based on other satellite-based rainfall data, including the Global Precipitation Mission (GPM).

SPI↗

NASA NTRSDate not supplied

Lessons Learned from Medical System Foundation Development for Long-Duration Lunar Orbit and Lunar Surface Missions

The Human Research Program (HRP) Exploration Medical Capability (ExMC) Element has been tasked with the development of Medical System Foundations for Level of Care IV for both short-duration lunar orbital missions and, subsequently, long-duration lunar orbital and surface operations missions. These Medical System Foundations serve as a framework to aid in early medical system design and mission planning. The content of both Foundation models is similar, consisting of a concept of operations, functional decomposition, clinical content (medical conditions, capabilities, and resources), technical requirements (interface, non-functional, and functional), and traces between these components and to the NASA standards documents and parent-level (Program- and Vehicle habitat system-level) requirements. Additionally, the development of both Foundations employed systems engineering principles and a model-based systems engineering (MBSE) approach. Throughout the development of these Foundations, ExMC has strived to improve the efficiency and robustness of its processes and to be more responsive to change (i.e., in design reference mission parameters and assumptions) and to stakeholders’ feedback. The most significant improvements made between the short- and long-duration Foundation models during this transformation process are the following: • Replacement of the traditional document-based ConOps with a model-based ConOps according to MBSE principles, which facilitated more efficient understanding of the material and the consolidation of all relevant information into a centralized location. • Utilization of an agile approach with tasks organized into sprints. This approach enabled solicitation of more frequent usability feedback from stakeholders, incorporation of more human factors reviews into the sprints, and more efficient tasking of team members. This presentation will discuss the journey of developing both Foundation models, as well as the lessons learned and resulting improvements made between the Short- and Long-Duration models.

M Kaetzer↗

NASA NTRSDate not supplied

Long Duration Medical System Foundation for Lunar Orbital and Lunar Surface Exploration Missions

For long-duration lunar orbital and lunar surface (LDLOS) exploration missions, the NASA Human Research Program (HRP) Exploration Medical Capability (ExMC) Element has developed a medical system foundation through which clinical considerations may be represented via a systems engineering-based model. Components of the Long Duration Medical System Foundation model include a concept of operations (ConOps), functional decomposition, medical conditions to be addressed, clinical capabilities and resources, technical requirements, and traces of requirements to NASA standards documents and parent-level (Program- and Vehicle habitat system-level) requirements. The Foundation model offers the means to present information in a readily accessible format that is understandable across all clinical, engineering, scientific, and managerial disciplines. Collectively, these components constitute a foundation that serves future programs with similar long duration mission profiles as a starting point for medical system design. The Foundation was developed by a multidisciplinary team of systems engineers, scientists, and clinicians across NASA. The process started with ConOps development, subsequently decomposed into the functionalities needed to diagnose, treat, and prevent medical conditions. The clinical team identified medical conditions most likely needed to be diagnosed and treated during a long-duration lunar exploration mission. Through these approaches, requirements were codified for the LDLOS medical system. These requirements were then traced to NASA standards, medical conditions, medical capabilities, and medical resources, facilitating stakeholders’ use of the Foundation model to analyze traces and to identify medical system interfaces with other vehicle systems or subsystems. In addition, the Foundation may be used as a basis for performing risk trades on medical system mass and volume allocation. This discussion will focus on the processes through which the LDLOS Medical System Foundation was developed, how the Foundation builds a bridge between the medical and engineering domains, and how these processes may be applied more broadly to a crew health and performance system and other system domains.

Jay Lemery↗

NASA NTRS2024

Quantifying Risk to Improve Medical System Design for Long Duration Artemis Missions: A Demonstration of NASA's IMPACT Tradespace Analysis Tool

BACKGROUND NASA’s human exploration spaceflight missions to the Moon and Mars present unprecedented challenges for in-mission medical care. A greater distance from Earth will mean increased mission durations, communication delays, limited to no resupply opportunities, and constraints on the evacuation of ill or injured crew. Mass, volume, and power will be limited while higher demands will be placed on the crews to manage medical events. NASA’s Moon to Mars exploration strategy outlines increasingly complex Artemis missions both in terms of duration and operations. In these more challenging deep space missions, it is important to quantitatively estimate the human system risk attributable to medical conditions and use these estimates to advance medical system design. METHODS IMPACT (Informing Mission Planning via Analysis of Complex Tradespaces) is a probabilistic risk assessment (PRA) and tradespace analysis tool developed by NASA to advance exploration mission medical system design. IMPACT v1.0 includes a novel evidence library baselined to exploration environments; an expanded list of 119 medical conditions; a large increase in the number of medical resources and the flexibility of their use; and the ability for rapid and iterative analysis. Medical system risk estimates include loss of crew life, consideration of the need for return to definitive care (medical evacuation), and an estimate of crew time affected due to medical conditions. A notional long duration lunar orbit and lunar surface design reference mission (DRM) was chosen with a 4-astronaut crew to mimic a foundational exploration Artemis mission. The DRM profile includes outbound transit on Orion, Gateway space station rendezvous in lunar orbit, 6 months on the Lunar surface with extravehicular activity (EVA), return rendezvous with Gateway, and transit back to Earth. RESULTS/DISCUSSION: Overall, IMPACT successfully quantified medical risk and derived an optimal medical system to support crew on a long duration lunar mission. In this DRM, the calculated loss of crew life from a medical event was 0.008 events per mission, risk of potential need for evacuation was 0.30 events per mission, and cumulative crew time affected by medical conditions was 103 days. The medical conditions that most contributed to medical risk were decompression sickness, trauma, and respiratory failure. The conditions that had the largest effects on crew performance included musculoskeletal injuries and lunar dust exposure. The IMPACT-generated medical system included resources that target the most common and highest risk conditions and performed as expected. This demonstrates the value of the IMPACT tool in medical system design for human exploration spaceflight missions.

Arian Anderson↗

NASA NTRSDate not supplied

Quantifying Medical Risk on a Long Duration Lunar Mission: A Demonstration of NASA’s IMPACT Tradespace Analysis Tool

Background NASA’s human exploration spaceflight missions to the Moon and Mars present unprecedented challenges for in-mission medical care. The distance from Earth will mean increased mission durations, communication delays, limited to no resupply opportunities, and constraints on the medical evacuation of astronauts. Mass, volume, power, and data will be limited while higher demands will be placed on the crew to manage medical care. NASA’s Moon to Mars exploration strategy lays out increasingly complex Artemis missions both in terms of duration and operations. In these more challenging deep space missions, it is important to quantitatively estimate the human medical risk to inform a traditional heuristic approach to medical risk. Prior tools have been developed for missions in low Earth orbit, but a new tool is required to plan for future exploration missions. Methods IMPACT (Informing Mission Planning via Analysis of Complex Tradespaces) is a risk assessment tool developed by NASA to advance exploration mission medical system design by quantitatively estimating mission medical risk. IMPACT v1.0 includes a novel evidence library baselined to exploration environments; an expanded list of 119 medical conditions; the addition of medical resources; and the ability for rapid and iterative analysis. Medical system risk estimates include loss of crew life, consideration of the need for return to definitive care (medical evacuation), and an estimate of crew time affected due to medical conditions. A notional long duration lunar orbit and lunar surface design reference mission (DRM) was chosen with a 4-astronaut crew to represent a sustained exploration Artemis mission. Results/Discussion Overall, IMPACT successfully quantified medical risk and derived an optimized medical system to support crew on a long duration lunar mission. In this DRM, the calculated loss of crew life from a medical event was 0.008 events per mission, risk of potential need for evacuation was 0.30 events per mission, and cumulative crew time affected by medical conditions was 103 days. The medical conditions that most contributed to overall medical risk were decompression sickness, trauma conditions, and respiratory failure. The conditions that had the largest effects on crew performance included musculoskeletal injuries and lunar dust exposure. The IMPACT-generated medical system included resources that target the most common and highest risk conditions. This systematic analysis demonstrates the value of the IMPACT tool in medical system design for human exploration spaceflight missions.

Missions to Mars↗

NASA NTRS2024

Quantifying Medical Risk on a Long Duration Lunar Mission: A Demonstration of NASA’s IMPACT Tradespace Analysis Tool

Missions to Mars↗

NASA NTRSDate not supplied

Bionutrients-1: Utilizing Genomics and Transcriptomics to Assess the Reliability of Microorganisms for In Situ Nutrient Production on Long Duration Missions

The resupply of current long-duration crewed missions to the ISS relies on ground-launched supplies. As NASA looks toward Mars, ground-based resupply will no longer be an option. Critical nutrients, including vitamin C, vitamin K, folate, and thiamin, degrade during long-term storage, and regular consumption of these nutrients is essential for astronaut health. Another challenge of current food systems is the difficulty of consuming sufficient calories when subsisting on the limited flavors of freeze-dried food, which can lead to weight loss. The inclusion of microorganism-based food systems could alleviate both concerns. For example, the fermentation of rehydrated milk into yogurt with microorganisms genetically incorporating genes to produce critical vitamins would allow for both in situ production of nutrients and a fresh food product with additional flavor profiles. In comparison to plant food production, microorganisms require less flight infrastructure. The BioNutrients-1 mission is demonstrating viability of microbial fermentation food production in microgravity and testing the reliability of this approach for long-duration missions lacking resupply. While the BioNutrients-1 mission includes the collection of multiple phenotypic measurements, this status update will focus on the processing of samples for genomics and transcriptomics analyses as well as the planned analysis pipelines. First, the BioNutrients-1 mission seeks to identify microorganisms capable of surviving long-duration storage at ambient temperatures while maintaining genetic fidelity. To achieve this, nine commonly employed microbial species were stored at ambient temperatures in Stasis Packs on the ISS for five years. The viability and mutation rates will be measured at multiple time points for both flown and ground control samples. From an omics perspective, the changes in the bulk rates of point mutations and genetic rearrangements across the Stasis Pack species during the five years of storage will be determined, providing valuable insights into the potential of these microorganisms for long-duration space missions. Second, the BioNutrients-1 mission is characterizing the impact of microgravity on fermentation. Two strains of the yeast Saccharomyces cerevisiae, each encoding antioxidants (β-carotene or zeaxanthin) were flown to ISS for storage and fermentation within simplified bioreactors (Production Packs). The impact of microgravity on the expression of the antioxidant production genes and general metabolic genes will be determined using RNA sequencing. Ultimately, the transcriptome data will be compared to phenotypic measurements, such as the antioxidant yield, end-state biomass, and the production of EtOH, to determine the impacts of microgravity and long-term storage on microbial fermentation. The findings from this research will be instrumental in understanding the challenges and opportunities of microorganism-based food systems in space missions.

BioNutrients↗