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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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At least 451 records · Page 25
All sourcesNASA NTRSDOE OSTI
NASA NTRS1992

Early SEI milestones - Underwater habitats and Antarctic research outposts as analogs for long duration spaceflight and lunar and Mars outposts

The use of analog environments for space research is considered focusing on underwater habitats and Antarctic research sites as analogous settings to long-duration space flight. It is pointed out that the use of these earth analogs can provide engineers, scientists, and future crew members with critical 'mission' experience at a relatively low cost.

Rummel, John D.↗
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 NTRS2017

Update of the NEXT Ion Thruster Service Life Assessment with Post-Test Correlation to the Long Duration Test

The service life assessment for NASA's Evolutionary Xenon Thruster is updated to incorporate the results from the successful and voluntarily early completion of the 51,184 hour long duration test which demonstrated 918 kg of total xenon throughput. The results of the numerous post-test investigations including destructive interrogations have been assessed against all of the critical known and suspected failure mechanisms to update the life and throughput expectations for each major component. Analysis results of two of the most acute failure mechanisms, namely pit-and-groove erosion and aperture enlargement of the accelerator grid, are not updated in this work but will be published at a future time after analysis completion.

ion engines↗
DOE OSTI2021

Systems and methods of long-duration energy storage and regeneration of energy-bearing redox pairs

Described herein are systems and methods of storing and delivering electrical using hydrogen at low-cost and for long-durations. The systems and methods use energy-bearing redox pairs that electrochemically bear energy through decoupled hydrogen and oxygen consumption and/or evolution reactions, which are typically associated with fuel cells. Each species of the energy-bearing redox pair is associated with a standard electrode potential within a water electrolysis voltage window for the electrolyte solution. Electrical energy delivery, hydrogen generation, electrolyte regeneration, or combinations thereof can be performed by logically or physically separated unit operations in a continuous manner, batch manner, or semi-batch manner facilitated by the energy-bearing redox pair.

08 HYDROGEN↗
NASA NTRS2017

Advances in Medical Analytics Solutions for Autonomous Medical Operations on Long-Duration Missions

A review will be presented on the progress made under STMDGame Changing Development Program Funding towards the development of a Medical Decision Support System for augmenting crew capabilities during long-duration missions, such as Mars Transit. To create an MDSS, initial work requires acquiring images and developing models that analyze and assess the features in such medical biosensor images that support medical assessment of pathologies. For FY17, the project has focused on ultrasound images towards cardiac pathologies: namely, evaluation and assessment of pericardial effusion identification and discrimination from related pneumothorax and even bladder-induced infections that cause inflammation around the heart. This identification is substantially changed due to uncertainty due to conditions of fluid behavior under space-microgravity. This talk will present and discuss the work-to-date in this Project, recognizing conditions under which various machine learning technologies, deep-learning via convolutional neural nets, and statistical learning methods for feature identification and classification can be employed and conditioned to graphical format in preparation for attachment to an inference engine that eventually creates decision support recommendations to remote crew in a triage setting.

Medical Decision Support Systems↗
NASA NTRS1995

Long Duration Exposure Facility (LDEF) space optics handbook

The overall objective of this effort is to construct a top-level space optics handbook that provides design guidelines based upon data collected from the Long Duration Exposure Facility (LDEF) experiment. The content of the handbook would cover optical coatings, surfaces, fiber optics, and fabricating process for lenses, windows and mirrors that were used on LDEF. The goal of this program (and handbook) is to ensure that the space community can derive the maximum benefit from the LDEF experiment relative to future optics designs for space applications. The summary of this handbook is 'What did we learn from the LDEF experiment?'

Kemp, William T.↗
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 NTRS2016

Pilot Field Test: Performance of a Sit-to-Stand Test After Long-Duration Space Flight

BACKGROUND: Astronauts returning from the International Space Station 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. METHODS: The first test in the PFT battery sequence, and also the least demanding one from the sensorimotor perspective, was a Sit-to-Stand test. Test subjects were seated in the chair and had to stand up on command and remain standing for ten seconds. The subjects were instructed to stand up unassisted as quickly as they were able to, while maintaining postural control. Synchronized wireless inertial sensors mounted on the head, chest, lower back, wrists, and ankles were used to continuously log body kinematics. Crewmembers' blood pressure and heart rate were monitored and recorded with the Portapres and Polar systems. Each session was recorded with a digital video camera. During data collections occurring within the 24-hour postflight period, crewmembers were also asked to (1) evaluate their perceived motion sickness symptoms on a 20-point scale before and after completion of the test and (2) estimate how heavy they felt compared to their normal (preflight) body weight. Consent to participate in PFT was obtained from 18 crewmembers (11 US Orbital Segment [USOS] astronauts and 7 Russian cosmonauts). For 10 subjects, the first set of data was collected in the medical tent in Soyuz landing zone (1-2 hours after landing); the other 8 subjects were tested at the Kazakhstan deployment airport (4-5 hours after landing). 8 of the 11 astronauts were tested twice more within the first 24 hours postflight, at a refueling stop on the way to Houston (approximately 13 hours after landing) and at the Johnson Space Center (approximately 24 hours after landing). Later postflight data were collected in the first two weeks on some crewmembers. Finally, 6 astronauts were tested 60+ days after landing to establish a delayed baseline. RESULTS/DISCUSSION: Two of the 18 PFT participants felt too ill to attempt any tests in Kazakhstan (at either the landing zone or deployment airport). The remaining test subjects completed the Sit-to-Stand test and their reported motion sickness scores were unaffected by this task. The task completion times and body kinematics data analysis are currently underway. Preliminary analysis of astronaut data shows a steep improvement in the time to complete the task on the second data take, and in some cases, the trend continues through day six postflight. Head and trunk pitch angles and pitch rates were also examined and increases in all measures are evident throughout the observed recovery period (60+ days postflight). Interesting patterns of head and trunk pitch coordination have also emerged. One of the data analysis objectives is comparison of initial postflight performance and recovery of experienced crewmembers and first-time fliers. Another one - possible differences in performance between USOS and Russian crewmembers.

Kofman, I. S.↗
NASA NTRS2018

Aiding in the Efforts of Bioregenerative Life Support for the Future Residents of Mars and Long-Duration Space Flights Plant Growth in Amended Martian Regolith Simulant

Currently, the goal of plant growth research at KSC (Kennedy Space Center) is to provide a sustainable source of healthy food on long-duration space flights so astronauts and future residents of Mars can get the nutrition they need and produce food, recycle the atmosphere, and aid in recycling water. The sustainable production of food will aid in the efforts of closed life support. Plants have a vital application for bioregenerative life support as demands for food and oxygen can be provided through photosynthesis, while the carbon dioxide from human respiration is removed. In order for a growing medium to provide for plant growth, it needs to provide support, oxygen, ions, and liquid to the plant. This summer research determines how amended Martian regolith simulant acts as a growing medium for plants through looking at the structural properties of each amendment. Mars is covered with regolith which is crushed volcanic rock that is composed of a high amount of perchlorate salts. The composition of Martian soil is such that it is roughly basaltic and consists of sulfur, nitrates, and oxychlorine species. Martian regolith simulants have been generated to further analyze plant growth and aim to replicate features of the reference sample. The JSC (Johnson Space Center) Mars-1A regolith simulant resembles Martian regolith at the Viking I landing site. The objectives of the research this summer at Kennedy Space Center are to devise a plant growth in amended JSC Mars-1A Martian regolith simulant and perform crop studies to assess the performance of full duration crop growth in amended Martian regolith simulant. This research will provide a deeper understanding of how the combination of soil amendments to Martian regolith has a synergistic effect on improving crop production The plant growth experiment will be completed with three treatments each containing inorganic and organic soil amendments.

Onsay, Daphne↗
NASA NTRS1989

JACEE long duration balloon flights

JACEE balloon-borne emulsion chamber detectors are used to observe the spectra and interactions of cosmic ray protons and nuclei in the energy range 1 to 100A TeV. Experience with long duration mid-latitude balloon flights and characteristics of the detector system that make it ideal for planned Antarctic balloon flights are discussed.

Burnett, T.↗
NASA NTRS1992

Long Duration Exposure Facility (LDEF) low-temperature heat pipe experiment package power system results

An overview of a self-contained Direct Energy Transfer Power System which was developed to provide power to the Long Duration Exposure Facility (LDEF) Low-Temperature Heat Pipe Experiment Package is presented. The power system operated successfully for the entire mission. Data recorded by the onboard recorder shows that the system operated within design specifications. Other than unanticipated overcharging of the battery, the power system operated as expected for nearly 32,000 low earth orbit cycles, and was still operational when tested after the LDEF recovery. Some physical damage was sustained by the solar array panels due to micrometeoroid hits, but there were not electrical failures.

Tiller, Smith E.↗
NASA NTRS1989

JACEE long duration balloon flights

JACEE balloon-borne emulsion chamber detectors are used to observe the spectra and interactions of cosmic ray protons and nuclei in the energy range 1 to 100A TeV. Experiments with long duration mid-latitude balloon flights and characteristics of the detector system that make it ideal for planned Antarctic balloon flights are discussed.

Burnett, T.↗
NASA NTRS2017

The Effects of CDKN1a/p21 on Oxidative Stress and Mitochondrial Function During Long Duration Spaceflight

Spaceflight factors, such as microgravity and space radiation, are known to put astronauts at risk for negative effects to their tissue regeneration and degenerative conditions. On our previous spaceflight research, we found that long duration spaceflight produced increased oxidative stress and activation of the inflammatory response as a major contributor to physiological changes, including alterations to the cardiovascular and musculoskeletal systems, metabolism, and the liver. Proliferation, apoptosis, and ion-channel remodeling of vascular smooth muscle cells, as well as endothelial inflammation, and nitric oxide synthase-nitric oxide system regulation have been shown by spaceflight and simulated spaceflight projects. CDKN1ap21 is a regulatory gene for tissue regeneration and also plays an important role in upregulating oxidative stress caused by radiation. In further research, we have also determined CDKN1ap21 to be overexpressed during spaceflight. When knocked out in mice, however, it protects against unloading-induced changes to the morphology and physiology of carotid arteries. In this proposal, we seek to test a potential dietary countermeasure to down-regulate CDKN1ap21 in the mice and protect against oxidative stress in the rodents. Specifically, we will expose both Wildtype and CDKN1ap21-null mice to hydrogen peroxide to induce oxidative stress and observe the molecular mechanisms in which a dietary supplement protects vascular smooth muscle cells against the consequences of the apoptotic environment within Wildtype mice versus the, hypothetically, sound physiology of CDKN1ap21-null mice. The successful completion of this experiment will conclusively determine accuracy of a dietary supplement as a CDKN1ap21 suppressor. This will provide a new perspective on the problem of increased oxidative stress developing into cardiovascular disease as a result of long-term space flight. This research will address the Human Research Plan Roadmaps Risk of Cardiac Rhythm Problems including CV-8, the Risk of Cardiovascular Disease and Other Degenerative Tissue Effects from Radiation Exposure including Degen-6 and Degen-7, and the Risk of Adverse Health Event from Radiation Exposure including IM-8. Additionally, this research will address Space Biology Research Plans questions SBP CMB-1, SBP CMB-3, and SB AN-2.

Oxidative Stress↗
NASA NTRS1991

Long Duration Exposure Facility (LDEF) low-temperature Heat Pipe Experiment Package (HEPP) power system results

An overview of a self contained Direct Energy Transfer (DET) Power System which was developed to provide power to the Long Duration Exposure Facility (LDEF) Heat Pipe Experiment Package (HEPP) Experiment. A brief synopsis of the flight characteristics of the power system are presented to illustrate the system's capability to function successfully in a low Earth orbit (LEO) space environment. The successful space flight operations of the battery, solar arrays, and power system electronics during the flight period of almost six years (approximately 32,000 LEO cycles) are discussed.

Tiller, Smith E.↗
NASA NTRS1997

Development of Insect Habitat System for Studying Long Duration Circadian Rhythm Changes on Mir Space Station

A habitat for housing up to 32 black body beetles (Trigonoscelis gigas) has been developed at Ames Research Center for conducting studies to evaluate the effects of long duration spaceflight upon insect circadian timing systems. This habitat, identified as the Beetle Kit Assembly, provides an automatically controlled lighting system and activity and temperature recording devices, as well as individual beetle enclosures. Each of the 32 enclosures allows for ad lib movement of the beetle, as well as providing a simple food source and allowing ventilation of the beetle volume via an externally operated hand pump. The Beetle Kit Assemblies will be launched on STS-84 (Shuttle-Mir Mission-06) in May, 1997 and will be transferred to the Priroda module of the Russian Mir space station. he beetles will remain on Mir for approximately 125 days, and will be returned to earth on STS-86 in September, 1997.

Savage, P. D.↗
NASA NTRS1999

The Effects of Long-Duration Spaceflight on Postflight Terrestrial Locomotion

Locomotion is a complex task requiring the coordinated integration of multiple sensorimotor subsystems. This coordination is exemplified by the precise control of segmental kinematics that allows smooth progression of movement in the face of changing environmental constraints. Exposure to the microgravity environment encountered during space flight induces adaptive modification in the central processing of sensory input to produce motor responses appropriate for the prevailing environment. This inflight adaptive change in sensorimotor function is inappropriate for movement control in 1-g and leads to postflight disturbances in terrestrial locomotor function. We have previously explored the effects of short-duration (7-16 days) space flight on the control of locomotion. The goal of the present set of studies was to investigate the effects of long-duration spaceflight (3-6 months) on the control of locomotion with particular emphasis on understanding how the multiple interacting systems are adaptively modified by prolonged microgravity exposure.

Bloomberg, J. J.↗
NASA NTRS2011

Full Mission Astronaut Radiation Exposure Assessments for Long Duration Lunar Surface Missions

Risk to astronauts due to ionizing radiation exposure is a primary concern for missions beyond Low Earth Orbit (LEO) and will drive mission architecture requirements, mission timelines, and operational practices. For short missions, radiation risk is dominated by the possibility of a large Solar Particle Event (SPE). Longer duration missions have both SPE and Galactic Cosmic Ray (GCR) risks. SPE exposure can contribute significantly toward cancer induction in combination with GCR. As mission duration increases, mitigation strategies must address the combined risks from SPE and GCR exposure. In this paper, full mission exposure assessments were performed for the proposed long duration lunar surface mission scenarios. In order to accomplish these assessments, previously developed radiation shielding models for a proposed lunar habitat and rover were utilized. End-to-End mission exposure assessments were performed by first calculating exposure rates for locations in the habitat, rover, and during Extra-Vehicular Activities (EVA). Subsequently, total mission exposures were evaluated for the proposed timelines. Mission exposure results, assessed in terms of effective dose, are presented for the proposed timelines and recommendations are made for improved astronaut shielding and safer operational practices.

Adamczyk, Anne↗