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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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NASA NTRS1977

Lithium cell tests at Langley Research Center

The long duration exposure facility mission places temperature requirements of from -30 F to +150 F on the batteries to be used. A hermetically sealed lithium sulfur dioxide cell was tested to predict what the temperature of the battery would be over a given spectrum of temperatures of operation. Near the end of cell discharge, as the voltage started collapsing, a very high heat output rise due to chemical reaction took place. However, if the cells were thermally insulated, they vented, ignited, and burned if an attempt was made to discharge them all the way. The cells do not go into reversal. It was determined that the root of the problem was probably the chemical reaction between the lithium and the acetonitrite solvent. A redesigned cell is discussed as well as some alternates.

Bene, J.↗
NASA NTRS2016

Development of a Mars Environmental Control and Life Support System (ECLSS).

ECLS systems for very long-duration human missions to Mars will be designed to operate reliably for many years and will never be returned to Earth. The need for high reliability is driven by unsympathetic abort scenarios. Abort from a Mars mission could be as long as 450 days to return to Earth. Simply put, the goal of an ECLSS is to duplicate the functions the Earth provides in terms of human living and working on our home planet but without the benefit of the Earth's large buffers - the atmospheres, the oceans and land masses. With small buffers a space-based ECLSS must operate as a true dynamic system rather than independent processors taking things from tanks, processing them, and then returning them to product tanks. Key is a development process that allows for a logical sequence of validating successful development (maturation) in a stepwise manner with key performance parameters (KPPs) at each step; especially KPPs for technologies evaluated in a full systems context with human crews on Earth and on space platforms such as the ISS. This paper will explore the implications of such an approach to ECLSS development and the roles of ground and space-based testing necessary to develop a highly reliable life support system for long duration human exploration missions. Historical development and testing of ECLS systems from Mercury to the International Space Station (ISS) will be reviewed. Current work as well as recommendations for future work will be described.

Henninger, Donald L.↗
NASA NTRS1979

Serendipitous solution to the problem of culturing Arabidopsis plants in sealed containers for spaceflights of long duration

The Arabidopsis thaliana plant species is tested to determine how a higher plant will develop from seed to maturity when deprived of all gravitational information that it might use to control its growth. Experimental results show that Arabidopsis seedlings can develop to maturity by means of a light-dependent but CO2-independent metabolism that feeds on organic compounds derived from the culture medium. This process is identified as photoassimilation. The ability of a higher plant to nourish itself by photoassimilation and thereby to survive in a heremetically sealed chamber of small dimensions is more than a biochemical curiosity. It allows the botanical investigator to design a culture system convenient for space-flight applications, which ensures isolation of each test plant from the gaseous environment of the spacecraft.

Brown, A. H.↗
NASA NTRS2016

Pilot Field Test: The Ability to Ambulate Following Landing as Assessed with Seat Egress, Walk and Obstacle Testing

To date, changes in functional performance have been systematically studied after short-duration space flight. As important as the postflight functional changes have been, full functional recovery has never been investigated or established for long-duration flights. The Pilot Field Test (PFT) experiment, conducted with participation of ISS crewmembers traveling on Soyuz expeditions 34S - 41S, is comprised of several tasks designed to study the recovery of sensorimotor abilities of astronauts during the first 24 hours after landing and beyond. The objective of the Seat Egress - Walk and Obstacle Test, developed by NASA's Russian collaborators at the Institute for Biomedical Problems, is to address this gap in knowledge. This will allow us to characterize the ability of crewmembers to perform critical mission requirements that they will be expected to perform after an unassisted landing following 6 to 12 months in microgravity.

Fisher, E. A.↗
NASA NTRS1993

Concept report: Experimental vector magnetograph (EXVM) operational configuration balloon flight assembly

The observational limitations of earth bound solar studies has prompted a great deal of interest in recent months in being able to gain new scientific perspectives through, what should prove to be, relatively low cost flight of the magnetograph system. The ground work done by TBE for the solar balloon missions (originally planned for SOUP and GRID) as well as the rather advanced state of assembly of the EXVM has allowed the quick formulation of a mission concept for the 30 cm system currently being assembled. The flight system operational configuration will be discussed as it is proposed for short duration flight (on the order of one day) over the continental United States. Balloon hardware design requirements used in formulation of the concept are those set by the National Science Balloon Facility (NSBF), the support agency under NASA contract for flight services. The concept assumes that the flight hardware assembly would come together from three development sources: the scientific investigator package, the integration contractor package, and the NSBF support system. The majority of these three separate packages can be independently developed; however, the computer control interfaces and telemetry links would require extensive preplanning and coordination. A special section of this study deals with definition of a dedicated telemetry link to be provided by the integration contractor for video image data for pointing system performance verification. In this study the approach has been to capitalize to the maximum extent possible on existing hardware and system design. This is the most prudent step that can be taken to reduce eventual program cost for long duration flights. By fielding the existing EXVM as quickly as possible, experience could be gained from several short duration flight tests before it became necessary to commit to major upgrades for long duration flights of this system or of the larger 60 cm version being considered for eventual development.

Source record↗
NASA NTRS2006

NASA Utilization of the International Space Station and the Vision for Space Exploration

In response to the U.S. President s Vision for Space Exploration (January 14, 2004), NASA has revised its utilization plans for ISS to focus on (1) research on astronaut health and the development of countermeasures that will protect our crews from the space environment during long duration voyages, (2) ISS as a test bed for research and technology developments that will insure vehicle systems and operational practices are ready for future exploration missions, (3) developing and validating operational practices and procedures for long-duration space missions. In addition, NASA will continue a small amount of fundamental research in life and microgravity sciences. There have been significant research accomplishments that are important for achieving the Exploration Vision. Some of these have been formal research payloads, while others have come from research based on the operation of International Space Station (ISS). We will review a selection of these experiments and results, as well as outline some of ongoing and upcoming research. The ISS represents the only microgravity opportunity to perform on-orbit long-duration studies of human health and performance and technologies relevant for future long-duration missions planned during the next 25 years. Even as NASA focuses on developing the Orion spacecraft and return to the moon (2015-2020), research on and operation of the ISS is fundamental to the success of NASA s Exploration Vision.

Robinson, Julie A.↗
NASA NTRS2006

NASA Utilization of the International Space Station and the Vision for Space Exploration

In response to the U.S. President's Vision for Space Exploration (January 14, 2004), NASA has revised its utilization plans for ISS to focus on (1) research on astronaut health and the development of countermeasures that will protect our crews from the space environment during long duration voyages, (2) ISS as a test bed for research and technology developments that will insure vehicle systems and operational practices are ready for future exploration missions, (3) developing and validating operational practices and procedures for long-duration space missions. In addition, NASA will continue a small amount of fundamental research in life and microgravity sciences. There have been significant research accomplishments that are important for achieving the Exploration Vision. Some of these have been formal research payloads, while others have come from research based on the operation of International Space Station (ISS). We will review a selection of these experiments and results, as well as outline some of ongoing and upcoming research. The ISS represents the only microgravity opportunity to perform on-orbit long-duration studies of human health and performance and technologies relevant for future long-duration missions planned during the next 25 years. Even as NASA focuses on developing the Orion spacecraft and return to the moon (2015-2020), research on and operation of the ISS is fundamental to the success of NASA s Exploration Vision.

Robinson, Julie A.↗
NASA NTRS2007

NASA Utilization of the International Space Station and the Vision for Space Exploration

In response to the U.S. President s Vision for Space Exploration (January 14, 2004), NASA has revised its utilization plans for ISS to focus on (1) research on astronaut health and the development of countermeasures that will protect our crews from the space environment during long duration voyages, (2) ISS as a test bed for research and technology developments that will insure vehicle systems and operational practices are ready for future exploration missions, (3) developing and validating operational practices and procedures for long-duration space missions. In addition, NASA will continue a small amount of fundamental research in life and microgravity sciences. There have been significant research accomplishments that are important for achieving the Exploration Vision. Some of these have been formal research payloads, while others have come from research based on the operation of International Space Station (ISS). We will review a selection of these experiments and results, as well as outline some of ongoing and upcoming research. The ISS represents the only microgravity opportunity to perform on-orbit long-duration studies of human health and performance and technologies relevant for future long-duration missions planned during the next 25 years. Even as NASA focuses on developing the Orion spacecraft and return to the moon (2015-2020), research on and operation of the ISS is fundamental to the success of NASA s Exploration Vision.

Robinson, Julie A.↗
NASA NTRS2010

Effects of Short- and Long-Duration Space Flight on Neuromuscular Function

The Functional Task Tests (FTT) is an interdisciplinary study designed to correlate the changes in functional tasks (such as emergency egress, ladder climbing, and hatch opening) with changes in neuromuscular, cardiovascular, and sensorimotor function. One aspect of the FTT, the neuromuscular function test, is used to investigate the neuromuscular component underlying changes in the ability of astronauts to perform functional tasks (representative of critical mission tasks) safely and quickly after flight. PURPOSE: To describe neuromuscular function after short- and long-duration space flight. METHODS: To date, 5 crewmembers on short-duration (10- to 15-day) missions and 3 on long-duration missions have participated. Crewmembers were assessed 30 days before flight, on landing day (short-duration subjects only) and 1, 6, and 30 days after landing. The interpolated twitch technique, which utilizes a combination of maximal voluntary contractions and electrically evoked contractions, was used to assess the maximal voluntary isometric force (MIF) and central activation capacity of the knee extensors. Leg-press and bench-press devices were used to assess MIF and maximal dynamic power of the lower and upper body respectively. Specifically, power was measured during concentric-only ballistic throws of the leg-press sled and bench-press bar loaded to 40% and 30% of MIF respectively. RESULTS: Data are currently being collected from both Shuttle and ISS crewmembers. Emerging data indicate that measures of knee extensor muscle function are decreased with long-duration flight. DISCUSSION: The relationships between flight duration, neural drive, and muscle performance are of particular interest. Ongoing research will add to the current sample size and will focus on defining changes in muscle performance measures after long-duration space flight.

Buxton, Roxanne E.↗
NASA NTRS2016

Pilot Field Test: Recovery from a Simulated Fall and Quiet Stance Stability After Long-Duration Space Flight

Astronauts returning from the International Space Station (ISS) are met by a team of recovery personnel typically providing physical assistance and medical support immediately upon landing. That is because long-duration spaceflight impacts astronauts' functional abilities. Future expeditions to planets or asteroids beyond the low Earth orbit, however, may require crewmembers to egress the vehicle and perform other types of physical tasks unassisted. It is therefore important to characterize the extent and longevity of functional deficits experienced by astronauts in order to design safe exploration class missions. Pilot Field Test (PFT) experiment conducted with participation of ISS crewmembers traveling on Soyuz expeditions 34S - 41S comprised several tasks designed to study the recovery of sensorimotor abilities of astronauts during the first 24 hours after landing and beyond.

Kofman, I. S.↗
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 NTRSDate not supplied

Long Duration Storage of Liquid Hydrogen via Two-Stage Active Cooling Hardware Characterization and Test Planning

The zero boil-off storage of liquid hydrogen using active cooling (cryocoolers) with a two-stage cooling approach is being investigated by NASA. In interest of advancing the technology to enable extended duration storage for the agency’s future long duration missions, NASA’s Technology Demonstration Mission Program has funded this five-year effort which includes the design, build and testing of a test article to demonstrate this concept. This paper includes discussions of the multiple Cryogenic Fluid Management technologies that were studied under NASA’s Cryogenic Propellant Storage and Transfer project, design of the test article to be demonstrated, then the planned test objectives which include characterization testing of the active cooling system, demonstration of the control system, preliminary testing with liquid nitrogen, and a complete demonstration of zero boil-off storage of liquid hydrogen. The full demonstration will be conducted in the East Test Area at NASA Marshall Space Flight Center and is currently scheduled to begin on October 1st, 2024.

Cryogenic Fluid Management↗
NASA NTRSDate not supplied

Control System Development for A Zero Boil-Off Hydrogen Storage Demonstration With Two-Stage Active Cooling

A NASA team is designing and building a test article to demonstrate the long duration storage of liquid hydrogen via active cooling (cryocoolers) while implementing a two-stage cooling approach. This activity is one of a large portfolio of NASA’s Space Technology Mission Directorate funded activities which focuses on the technology maturation needed for long duration storage of cryogenic liquid in-space. The current state-of-the-art for liquid hydrogen storage on-orbit is on the order of hours while NASA’s planned missions require storage for months, or even years. To enable such a long duration, Zero Boil-Off conditions must be achieved which requires passive technologies to minimize environmental heat loads, but also active cooling to intercept and reject the remaining heat to deep space. The implementation of active cooling results in a significant amount of dry mass added to the vehicle. Utilizing a Two-Stage Cooling approach, analysis and testing to date indicates the Zero Boil-Off of liquid hydrogen can be achieved with less mass and electrical power relative to a single-stage cooling approach where only one cryocooler is used. This activity will demonstrate the fully integrated suite of technologies needed to enable the Two-Stage Cooling approach which includes Multi-Layer Insulation blankets, Low Conductivity Structures, a Tube-On-Tank Heat Exchanger, Tube-On-Shield Heat Exchanger and a Two-Stage Cryogenerator (both 90 Kelvin and 20 Kelvin) with each stage having an independently controlled circulation loop. The bulk of the heat load is intercepted by the 90 Kelvin loop via a thin foil heat exchanger internal to the insulation blankets (also known as a Broad Area Cooling Shield), with the remainder removed at cryofluid temperature (20 Kelvin) by tubes directly welded to the outer tank surface. In this paper, we examine the challenges of controlling the system, and describe the development of control algorithms and software for future testing with liquid hydrogen. The interactions between the cryofans which control circulation loop mass flow rates, electrical heaters which vary the cryocooler lift to simulate the operation of variable-lift flight units, tank heaters which can vary the overall heat load, and the effects of changes in circulation loop pressure as temperatures change, can be complex and must be well understood to maintain steady-state propellant conditions and achieve Zero Boil-Off. Parallel PID loops and watchdog programs implemented on the user interface system will help bring the systems to steady state operation and keep them at selected operating points within acceptable error, while avoiding runaway feedback loops.

cryogenics↗
NASA NTRS1999

Volatiles Evolved from Soybean Products Intended for Use in Long Duration Space Missions

Soybeans have been baselined to be grown in a habitat (Advanced Life Support Systems Integration Test Bed, ALSSITB) intended for evaluating advanced life support systems developed for long duration missions to the Moon or Mars. The ALSSITB is being constructed at NASA-Johnson Space Center and is composed of 5 chambers (4.6 m x 11.3 m each) and an airlock joined by an interconnecting tunnel (3.7 m x 19.2 m). Processed soy products such as soy milk and soy bread are planned to be incorporated into a nutritionally sound, plant-based food system. Since all consumables will be recycled and reused, volatile compounds evolved during the manufacturing of these food products need to be quantified to assess their impact on this closed loop system. Soy milk was made in a prototype machine and bread in a commercial bread baking machine. These machines were each placed in a tightly closed chamber and, at the completion of the process, air volatiles were identified and quantified by GC/MS. For soy milk, ethanol, acetaldehyde, methanol, hexanal, propanal and acetone and for soybread, acetaldehyde, ethanol, N-propanol and ethyl acetate were detected in significant quantities. The crew members will spend an average of 180 days in the ALSSITB and it was estimated that 138 batches of soy milk will be processed in the tunnel and 130 loaves of soybread would be baked in the habitat chamber during their stay. The aforementioned volatiles would surpass the 180 day Spacecraft Maximum Allowable Concentrations (SMACs) if no means of scrubbing are adapted which would lead to toxic levels of these compounds. Therefore, sufficient means for eliminating the contribution of volatiles evolved from food processing and preparation equipment needs to be provided in the ALSSITB.

Vodovotz, Yael↗
NASA NTRS2010

Altitude Testing of Large Liquid Propellant Engines

The National Aeronautics and Space Administration entered a new age on January 14, 2004 with President Bush s announcement of the creation the Vision for Space Exploration that will take mankind back to the Moon and on beyond to Mars. In January, 2006, after two years of hard, dedicated labor, engineers within NASA and its contractor workforce decided that the J2X rocket, based on the heritage of the Apollo J2 engine, would be the new engine for the NASA Constellation Ares upper stage vehicle. This engine and vehicle combination would provide assured access to the International Space Station to replace that role played by the Space Shuttle and additionally, would serve as the Earth Departure Stage, to push the Crew Excursion Vehicle out of Earth Orbit and head it on a path for rendezvous with the Moon. Test as you fly, fly as you test was chosen to be the guiding philosophy and a pre-requisite for the engine design, development, test and evaluation program. An exhaustive survey of national test facility assets proved the required capability to test the J2X engine at high altitude for long durations did not exist so therefore, a high altitude/near space environment testing capability would have to be developed. After several agency concepts the A3 High Altitude Testing Facility proposal was selected by the J2X engine program on March 2, 2007 and later confirmed by a broad panel of NASA senior leadership in May 2007. This facility is to be built at NASA s John C. Stennis Space Center located near Gulfport, Mississippi. 30 plus years of Space Shuttle Main Engine development and flight certification testing makes Stennis uniquely suited to support the Vision For Space Exploration Return to the Moon. Propellant handling infrastructure, engine assembly facilities, a trained and dedicated workforce and a broad and varied technical support base will all ensure that the A3 facility will be built on time to support the schedule needs of the J2X engine and the ultimate flight of the first Ares I vehicle. The A3 facility will be able to simulate pre-ignition altitude from sea-level to 100,000 feet and maintain it up to 650 seconds. Additionally the facility will be able to accommodate initial ignition, shutdown and then restart test profiles. A3 will produce up to 5000 lbm/sec of superheated steam utilizing a Chemical Steam generation system. Two separate inline steam ejectors will be used to produce a test cell vacuum to simulate the 100,000 ft required altitude. Operational capability will ensure that the facility can start up and shutdown without producing adverse pressure gradients across the J2X nozzle. The facility will have a modern thrust measurement system for accurate determination of engine performance. The latest advances in data acquisition and control will be incorporated to measure performance parameters during hotfire testing. Provisions are being made in the initial design of the new altitude facility to allow for testing of other, larger engines and potential upper stage launch vehicles that might require vacuum start testing of the engines. The new facility at Stennis Space Center will be complete and ready for hotfire operations in late 2010.

Maynard, Bryon T.↗
NASA NTRSDate not supplied

Capability Gaps Assessment and Identification of Critical Technology Elements for Mars Transit Habitat

The Habitation Systems Development Office (HP40) at NASA Marshall Space Flight Center supports systems engineering, integration, and project management for next generation space habitats. For in space operations and eventual transport of humans to Mars, NASA will rely on a Mars Transit Habitat (TH). The TH will be designed for an up to 1,200-day Mars mission and will carry all food and supplies needed to support four crew for this duration. In the current concept of operations, Mars TH transfers to near rectilinear halo orbit (NRHO) following launch and docks at Gateway as a visiting vehicle. While there, the TH will complete system shakedown testing and a series of analog missions which will grow from 3 to 6+ months in duration TH also augments Gateway’s habitation capabilities beyond 60-days. Proposed Gateway-TH missions will far exceed the longest duration cislunar human missions to date. These shakedown missions will also be the first operational readiness tests of Mars TH’s long-duration deep space systems, and of the split crew (two crew on the surface, two crew in space) operations that are vital to the approach for the first human Mars mission. Once shakedown missions are complete, Mars TH departs Gateway to aggregate with the Mars propulsion system in NRHO before onboarding the crew and final supplies in Earth orbit via a co-manifested Orion-logistics module. Orion and the LM return to Earth prior to the now aggregated Deep Space Transport vehicle’s journey to Mars. Development of the Mars TH requires significant technology development and maturation. Each year the agency performs a capability gaps assessment, where gaps developed by subject matter experts (SMEs) in various engineering/science disciplines are linked to architectural elements in formulation and prioritized. A gap captures the difference between the current state-of-the-art and the maturity of the capability that is needed to enable or enhance a mission as it is currently envisioned in the government reference architecture. HP40 conducted a gap analysis for Mars TH which will be summarized in this poster. Gaps classified as enabling (which means the mission cannot achieve success without gap closure) were subsequently used to identify critical technology elements (CTEs) for Mars TH. This identification of CTEs was also informed by an examination of the product breakdown structure for Mars TH and focused conversations with SMEs in specific technology areas. CTEs identified for Mars TH to date include the following (note this is not a comprehensive list – CTEs listed represent those in MSFC’s capability areas): inflatable softgoods for habitation; enhanced CO2 recovery; life support systems with greater levels of reliability and maintainability; autonomous guidance, navigation, command and control; and radiators for the Mars TH application. The habitation systems development team is currently delving deeper into each CTE to assess technology approaches being pursued, their maturity, and the degree of difficulty in maturation to meet projected Mars TH timelines. This poster will summarize work to date on the identification of enabling capability gaps linked to Mars TH and provide insight into the associated CTEs and technology maturation efforts.

technology development↗
NASA NTRS2013

Development and Execution of Autonomous Procedures Onboard the International Space Station to Support the Next Phase of Human Space Exploration

Now that major assembly of the International Space Station (ISS) is complete, NASA's focus has turned to using this high fidelity in-space research testbed to not only advance fundamental science research, but also demonstrate and mature technologies and develop operational concepts that will enable future human exploration missions beyond low Earth orbit. The ISS as a Testbed for Analog Research (ISTAR) project was established to reduce risks for manned missions to exploration destinations by utilizing ISS as a high fidelity micro-g laboratory to demonstrate technologies, operations concepts, and techniques associated with crew autonomous operations. One of these focus areas is the development and execution of ISS Testbed for Analog Research (ISTAR) autonomous flight crew procedures intended to increase crew autonomy that will be required for long duration human exploration missions. Due to increasing communications delays and reduced logistics resupply, autonomous procedures are expected to help reduce crew reliance on the ground flight control team, increase crew performance, and enable the crew to become more subject-matter experts on both the exploration space vehicle systems and the scientific investigation operations that will be conducted on a long duration human space exploration mission. These tests make use of previous or ongoing projects tested in ground analogs such as Research and Technology Studies (RATS) and NASA Extreme Environment Mission Operations (NEEMO). Since the latter half of 2012, selected non-critical ISS systems crew procedures have been used to develop techniques for building ISTAR autonomous procedures, and ISS flight crews have successfully executed them without flight controller involvement. Although the main focus has been preparing for exploration, the ISS has been a beneficiary of this synergistic effort and is considering modifying additional standard ISS procedures that may increase crew efficiency, reduce operational costs, and raise the amount of crew time available for scientific research. The next phase of autonomous procedure development is expected to include payload science and human research investigations. Additionally, ISS International Partners have expressed interest in participating in this effort. The recently approved one-year crew expedition starting in 2015, consisting of one Russian and one U.S. Operating Segment (USOS) crewmember, will be used not only for long duration human research investigations but also for the testing of exploration operations concepts, including crew autonomy.

beyond low earth orbit (BLEO)↗
NASA NTRS2023

A Review of the Safety of Selective Serotonin Reuptake Inhibitors for Long Duration Spaceflight

Introduction: As humankind ventures further into the depths of space, planning is already underway for long-duration exploration missions that will test the bounds of human performance. Deep space travel will include added risk related to stressors from the isolated, confined, and extreme (ICE) environment that lies outside the boundaries of low-earth orbit. Currently, selective serotonin reuptake inhibitors (SSRIs) are considered the gold standard treatment for many mental health diagnoses including anxiety and depression; however, SSRIs are also associated with several undesired side effects. The utility of non-pharmacologic therapies for the management of behavioral health conditions has not yet been fully explored. Methods: A comprehensive literature search was performed using PubMed and relevant articles pertaining to the psychological impacts of ICE environments, use of SSRIs in spaceflight, side effects associated with SSRIs, and non-pharmacologic treatments for anxiety and depression were reviewed. Over 100 studies were reviewed in total. Results: Reduced bone mineral density, impaired hemostatic function, significant individual variability resulting from gene polymorphisms, and drug-drug interactions are well described adverse effects of SSRIs that may complicate their operational use in the deep space environment. Many non-pharmacologic therapies have been utilized with success for the management of behavioral health conditions in the terrestrial environment that may show promise for long duration missions. Discussion: Although SSRIs have long been considered standard of care treatment for many behavioral health conditions, we cannot trivialize the risk that prolonged pharmacologic therapy may pose. The need to mitigate these risks by exploring alternative non-pharmacologic therapies has never been more relevant.

Charles H Dukes↗