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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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All sourcesNASA NTRSDOE OSTI
NASA NTRS2003

Planetary protection and the search for life beneath the surface of Mars

The search for traces of extinct and extant life on Mars will be extended to beneath the surface of the planet. Current data from Mars missions suggesting the presence of liquid water early in Mars' history and mathematical modeling of the fate of water on Mars imply that liquid water may exist deep beneath the surface of Mars. This leads to the hypothesis that life may exist deep beneath the Martian surface. One possible scenario to look for life on Mars involves a series of unmanned missions culminating with a manned mission drilling deep into the Martian subsurface (approximately 3Km), collecting samples, and conducting preliminary analyses to select samples for return to earth. This mission must address both forward and back contamination issues, and falls under planetary protection category V. Planetary protection issues to be addressed include provisions stating that the inevitable deposition of earth microbes by humans should be minimized and localized, and that earth microbes and organic material must not contaminate the Martian subsurface. This requires that the drilling equipment be sterilized prior to use. Further, the collection, containment and retrieval of the sample must be conducted such that the crew is protected and that any materials returning to earth are contained (i.e., physically and biologically isolated) and the chain of connection with Mars is broken. c2002 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

NASA Discipline Exobiology↗
NASA NTRS1990

Proton radiation effects on multi-pinned-phased CCDs

Three Tektronix 1024 x 1024 multi-pinned-phased (MPP) charge coupled devices were irradiated with protons to obtain data on CCD performance degradation in a proton radiation environment. The devices were irradiated with a spectrum of energies up to 120 MeV, simulating the total radiation dose of a long-term space experiment. Basic parameters such as charge transfer efficiency, dark current, noise, and full well were measured before and after irradiation. A test was also performed to determine the effectiveness of various thicknesses of tantalum shielding in protecting the CCD from damage. Dark current increase and CTE degradation were the most noticeable effects of proton radiation. This paper will present the objectives, test data, and conclusions of the proton testing, and will identify future testing to be performed.

Murata-Seawalt, D.↗
NASA NTRS2010

Current Applications of OMI Tropospheric NO2 Data for Air Quality and a Look to the Future

Ozone Monitoring Instrument (OMI) Tropospheric NO2 products are being used to enhance the ability to monitor changes in NO2 air quality, update emission inventories, and evaluate regional air quality models. Trends in tropospheric column NO2 have been examined over the eastern United States in relation to emissions changes mandated by regulatory actions. Decreases of 20 to 40 percent over the period 2005 to 2008 were noted, largely in response to major emission reductions at power plants. The OMI data have been used to identify regions in which the opposite trend has been found. We have also used OMI NO2 in efforts to improve emission inventories for NOx emissions from soil. Lightning NOx emissions have been added to CMAQ, the US Environmental Protection Agency's regional air quality model. Evaluation of the resulting NO2 columns in the model is being conducted using the OMI NO2 observations. Community Multiscale Air Quality (CMAQ) together with the OMI NO2 data comprise a valuable tool for monitoring and predicting air quality. Looking to the future, we expect that the combination of Global Ozone Monitoring Experiment-2 (GOME-2) (morning) and OMI (afternoon) data sets obtained through use of the same retrieval algorithms will substantially increase the possibility of successful integration of satellite information into regional air quality forecast models. Farther down the road, we anticipate the Geostationary Coastal and Air Pollution Events (GEO-CAPE) platform to supply data possibly on an hourly basis, allowing much more comprehensive analysis of air quality from space.

Pickering, Kenneth E.↗
NASA NTRS1974

Life sciences payload definition and integration study. Volume 2: Requirements, design, and planning studies for the carry-on laboratories

The task phase concerned with the requirements, design, and planning studies for the carry-on laboratory (COL) began with a definition of biomedical research areas and candidate research equipment, and then went on to develop conceptual layouts for COL which were each evaluated in order to arrive at a final conceptual design. Each step in this design/evaluation process concerned itself with man/systems integration research and hardware, and life support and protective systems research and equipment selection. COL integration studies were also conducted and include attention to electrical power and data management requirements, operational considerations, and shuttle/Spacelab interface specifications. A COL program schedule was compiled, and a cost analysis was finalized which takes into account work breakdown, annual funding, and cost reduction guidelines.

Source record↗
NASA NTRS1974

Systems Study of an Automated Fire Weather Data System

A sensor system applicable to an automated weather station was developed. The sensor provides automated fire weather data which correlates with manual readings. The equipment and methods are applied as an aid to the surveillance and protection of wildlands from fire damage. The continuous readings provided by the sensor system make it possible to determine the periods of time that the wilderness areas should be closed to the public to minimize the possibilities of fire.

Nishioka, K.↗
NASA NTRS1979

Use of arc-jet hypersonic blunted wedge flows for evaluating performance of Orbiter TPS

Arc-jet tests at NASA/JSC have been conducted recently to evaluate the performance of the Orbiter Thermal Protection System (TPS) on three critical areas of the side and top of the Orbiter fuselage: (1) cargo bay door, (2) crew access door, and (3) LRSI/FRSI joint regions. Test articles corresponding to these three areas on the Orbiter were mounted in an arc-jet test chamber in a blunted-wedge holder and exposed to hypersonic flow at various angles of attack. The effects of flow direction, heating load, and overtemperature were investigated. In addition, the reuse capability of the TPS materials was evaluated, along with the protection of the pressure seals within the test articles. Thermal match model predictions correlated well with primary structure thermocouple data. Heating rate and pressure predictions based on a nonequilibrium flow field computer program showed good agreement with arc-jet test data and existing hypersonic flow theories.

Rochelle, W. C.↗
NASA NTRS1989

Protection Against Brief Interruptions Of Power

Rotating standby power system compensates for brief interruptions in commercial power supply. System furnishes few cycles of alternating current from its stored rotational energy. Protects equipment vulnerable to brief losses of power; for example, prevents computers from erroneously suppressing or adding bits to data being handled at moment of power failure.

Casad, Theodore A.↗
NASA NTRS1992

Oxidation processes in magneto-optic and related materials

The surface oxidation processes of thin films of magneto-optic materials, such as the rare-earth transition metal alloys have been studied, starting in ultrahigh vacuum environments, using surface analysis techniques, as a way of modeling the oxidation processes which occur at the base of a defect in an overcoated material, at the instant of exposure to ambient environments. Materials examined have included FeTbCo alloys, as well as those same materials with low percentages of added elements, such a Ta, and their reactivities to both O2 and H2O compared with materials such as thin Fe films coated with ultrathin adlayers of Ti. The surface oxidation pathways for these materials is reviewed, and XPS data presented which indicates the type of oxides formed, and a critical region of Ta concentration which provides optimum protection.

Lee, Paul A.↗
NASA NTRS1999

Industrial Hygiene Issues

This breakout session is a traditional conference instrument used by the NASA industrial hygiene personnel as a method to convene personnel across the Agency with common interests. This particular session focused on two key topics, training systems and automation of industrial hygiene data. During the FY 98 NASA Occupational Health Benchmarking study, the training system under development by the U.S. Environmental Protection Agency (EPA) was deemed to represent a "best business practice." The EPA has invested extensively in the development of computer based training covering a broad range of safety, health and environmental topics. Currently, five compact disks have been developed covering the topics listed: Safety, Health and Environmental Management Training for Field Inspection Activities; EPA Basic Radiation Training Safety Course; The OSHA 600 Collateral Duty Safety and Health Course; and Key program topics in environmental compliance, health and safety. Mr. Chris Johnson presented an overview of the EPA compact disk-based training system and answered questions on its deployment and use across the EPA. This training system has also recently been broadly distributed across other Federal Agencies. The EPA training system is considered "public domain" and, as such, is available to NASA at no cost in its current form. Copies of the five CD set of training programs were distributed to each NASA Center represented in the breakout session. Mr. Brisbin requested that each NASA Center review the training materials and determine whether there is interest in using the materials as it is or requesting that EPA tailor the training modules to suit NASA's training program needs. The Safety, Health and Medical Services organization at Ames Research Center has completed automation of several key program areas. Mr. Patrick Hogan, Safety Program Manager for Ames Research Center, presented a demonstration of the automated systems, which are described by the following: (1) Safety, Health and Environmental Training. This system includes an assessment of training needs for every NASA Center organization, course descriptions, schedules and automated course scheduling, and presentation of training program metrics; (2) Safety and Health Inspection Information. This system documents the findings from each facility inspection, tracks abatement status on those findings and presents metrics on each department for senior management review; (3) Safety Performance Evaluation Profile. The survey system used by NASA to evaluate employee and supervisory perceptions of safety programs is automated in this system; and (4) Documentation Tracking System. Electronic archive and retrieval of all correspondence and technical reports generated by the Safety, Health and Medical Services Office are provided by this system.

Brisbin, Steven G.↗
NASA NTRS2000

Design of a 2-Hour Prebreathe Protocol for Space Walks (EVAs) from the International Space Station (ISS)

The majority of extravehicular activities (EVAs) performed from the shuttle use a 10.2 psi staged decompression. The International Space Station (ISS) will operate at 14.7 psi, requiring crews to "campout" in the airlock at 10.2 psi. The constraints associated with campout (crew isolation, oxygen usage, and waste management), provided the rationale to develop a 2-hour prebreathe protocol from 14.7 psi. Previous studies on the affect of microgravity and exercise during prebreathe suggested the feasibility of this approach. Various combinations of adynamia (nonwalking subjects), prebreathe exercise doses, and space suit donning options (10.2 vs. 14.7 psi) were analyzed against timeline and consumable constraints. Prospective decompression sickness (DCS) and venous gas emboli (VGE) accept/reject criteria were defined from statistical analysis of historical DCS data, combined with risk management of DCS under ISS mission circumstances. Maximum operational DCS levels were defined based on protecting for EVA capability with two crew members at 95% confidence, throughout ISS lifetime (within the constraints of NASA DCS disposition policy JPG 1800.3). The accept / reject limits were adjusted for greater safety (including Grade IV VGE criteria) based on analysis of related medical factors. Monte-Carlo simulation was performed to design a closed sequential, multi-center laboratory trial, including the capability of rejecting the primary protocol and testing at least one alternate exercise dose, within the 2-hour prebreathe. The 2-hour protocol incorporates 0, breathing for 5 0 min at 14.7 psi, including 10 min dual cycle ergometry at 75%VO(2max). It requires an additional 30 minO2breathing during depress from 14.7 to 10.2 psi, followed by a 30-60 min suit donning break at 10.2 psi/26.5% O2. It concludes with a 40 min in-suit O2 prebreathe. The protocol would be accepted for operations, if the incidence of DCS was less than 15% and Grade IV VGE less than 20%, both at 95% confidence. The above protocol and accept/reject limits were implemented in a multi-center study.

Gernhardt, M. L.↗
NASA NTRS2000

Design and Testing of a 2-Hour Oxygen Prebreathe Protocol for Space Walks from the International Space Station

To develop and test a 2-hour prebreathe protocol for performing extravehicular activities (EVAs) from the International Space Station (ISS). Combinations of adynamia (non-walking), prebreathe exercise, and space suit donning options (10.2 vs. 14.7 psi) were evaluated, against timeline and consumable contraints to develop an operational 2- hour prebreathe protocol. Prospective accept/reject criteria were defined for decompression sickness (DCS) and venous gas emboli (VGE) from analysis of historical DCS data, combined with risk management of DCS under ISS mission circumstances. Maximum operational DCS levels were defined based on protecting for EVA capability with two crew-members at 95% confidence, throughout ISS lifetime (within the constraints of NASA DCS disposition policy JPG 1800.3). The accept/reject limits were adjusted for greater safety based on analysis of related medical factors. Monte-Carlo simulation was performed to design a closed sequential, multi-center human trial. Protocols were tested with 4 different prebreathe exercises (Phases I-IV), prior to exposure to 4.3 psi for 4 hrs. Subject selection, Doppler monitoring for VGE, test termination criteria, and DCS definitions were standardized. Phase I: upper and lower body exercises using dual-cycle ergometry (75% VO2 max for 10 min). Phase II: ergometry plus 24 min of light exercise (simulating space-suit preparations). Phase III: same 24 min of light exercise but no ergometry, and Phase IV: 56 min of light exercise without ergometry. A prebreathe procedure was accepted if, at 95% confidence, the incidence of DCS was less than 15% (with no Type II DCS), and Grade IV VGE was less than 20%.

Gernhardt, Michael L.↗
NASA NTRS2005

Emissions Measured in the Exhaust of a CFM-56 Engine on a DC-8

A very extensive set of gaseous- and particulate-emissions data from an in service commercial aircraft engine was obtained by a team of researchers from NASA, the Environmental Protection Agency, and the Department of Defense. The program was led and organized by Dr. Chowen Wey of the UEET Project Office at the NASA Glenn Research Center and was dubbed the Aircraft Particle Emissions eXperiment (APEX). Testing was done at the NASA Dryden Flight Research Center. The main object of APEX was to identify particulate emissions from commercial-aircraft engines.

Wey, Changlie↗
NASA NTRS2011

Solid Rocket Booster (SRB) Flight System Integration at Its Best

The Solid Rocket Booster (SRB) element integrates all the subsystems needed for ascent flight, entry, and recovery of the combined Booster and Motor system. These include the structures, avionics, thrust vector control, pyrotechnic, range safety, deceleration, thermal protection, and retrieval systems. This represents the only human-rated, recoverable and refurbishable solid rocket ever developed and flown. Challenges included subsystem integration, thermal environments and severe loads (including water impact), sometimes resulting in hardware attrition. Several of the subsystems evolved during the program through design changes. These included the thermal protection system, range safety system, parachute/recovery system, and others. Because the system was recovered, the SRB was ideal for data and imagery acquisition, which proved essential for understanding loads, environments and system response. The three main parachutes that lower the SRBs to the ocean are the largest parachutes ever designed, and the SRBs are the largest structures ever to be lowered by parachutes. SRB recovery from the ocean was a unique process and represented a significant operational challenge; requiring personnel, facilities, transportation, and ground support equipment. The SRB element achieved reliability via extensive system testing and checkout, redundancy management, and a thorough postflight assessment process. However, the in-flight data and postflight assessment process revealed the hardware was affected much more strongly than originally anticipated. Assembly and integration of the booster subsystems required acceptance testing of reused hardware components for each build. Extensive testing was done to assure hardware functionality at each level of stage integration. Because the booster element is recoverable, subsystems were available for inspection and testing postflight, unique to the Shuttle launch vehicle. Problems were noted and corrective actions were implemented as needed. The postflight assessment process was quite detailed and a significant portion of flight operations. The SRBs provided fully redundant critical systems including thrust vector control, mission critical pyrotechnics, avionics, and parachute recovery system. The design intent was to lift off with full redundancy. On occasion, the redundancy management scheme was needed during flight operations. This paper describes some of the design challenges and technical issues, how the design evolved with time, and key areas where hardware reusability contributed to improved system level understanding.

Wood, T. David↗
NASA NTRS2014

High Energy Replicated Optics to Explore the Sun Balloon-Borne Telescope: Astrophysical Pointing

On September 21, 2013, the High Energy Replicated Optics to Explore the Sun, or HEROES, balloon-borne x-ray telescope launched from the Columbia Scientific Balloon Facility's site in Ft. Summer, NM. The flight lasted for approximately 27 hours and the observational targets included the Sun and astrophysical sources GRS 1915+105 and the Crab Nebula. Over the past year, the HEROES team upgraded the existing High Energy Replicated Optics (HERO) balloon-borne telescope to make unique scientific measurements of the Sun and astrophysical targets during the same flight. The HEROES Project is a multi-NASA Center effort with team members at both Marshall Space Flight Center (MSFC) and Goddard Space Flight Center (GSFC), and is led by Co-PIs (one at each Center). The HEROES payload consists of the hard X-ray telescope HERO, developed at MSFC, combined with several new systems. To allow the HEROES telescope to make observations of the Sun, a new solar aspect system was added to supplement the existing star camera for fine pointing during both the day and night. A mechanical shutter was added to the star camera to protect it during solar observations and two alignment monitoring systems were added for improved pointing and post-flight data reconstruction. This mission was funded by the NASA HOPE (Hands-On Project Experience) Training Opportunity awarded by the NASA Academy of Program/Project and Engineering Leadership, in partnership with NASA's Science Mission Directorate, Office of the Chief Engineer and Office of the Chief Technologist.

Gaskin, Jessica↗
NASA NTRS2016

Experiment Design and Characterization for the Study of Afterbody Radiation During Mars Entry

Recent work has shown that a significant contributor to the afterbody aeroheating during Mars entry is radiation. However, relevant ground test data is not available to help assess the uncertainty associated with prediction of the radiation when designing the thermal protection system for the aeroshell afterbody. The present work is aimed at designing an experiment which allows the study of the afterbody radiation experienced during Mars entry. The X2 expansion tube at the University of Queensland is used to generate the relevant experimental freestream flow conditions. Analysis is carried out to accurately characterize the generated experimental freestream conditions. A two dimensional wedge model is used to produce the expanding flow which simulates aspects of the afterbody flow around Mars entry vehicles. Preliminary analysis of the generated expanding flow shows that it produces significant radiation in the mid-infrared region and has a steady duration of about 50-110 μs. This allows emission spectroscopy to be conducted in the future.

Gu, S.↗
NASA NTRS2019

Nasa's Astromaterials Collections: Housed at the NASA Johnson Space Center (JSC) in Houston, TX

The Astromaterials Research and Exploration Science Division at JSC is responsible for the curation of extraterrestrial samples from NASA's past, present and future sample return missions. These samples provide data that help scientists better understand the history and evolution of our Solar System. Our mission is to preserve, protect, and distribute samples for research by the present and future scientific community.

Graff, Paige V.↗
NASA NTRS2022

Gaussian Process Regression Method for Costing SmallSat Bus Capabilities

NASA is responding to the growing interest in, andcapabilities of, small satellites for science applications with an increasingnumber and frequency of Announcements of Opportunityfor small satellite space missions. Estimating the probabilitythat these mission concepts will fit within the small cost capsof these opportunities is largely driven by the probability thatone of the burgeoning number of small satellite providers will beable to meet the payload’s accommodation requirements withinthe budget for the spacecraft. JPL has collected a databasecontaining technical specifications and cost of commerciallyavailable Smallsat buses across various vendors. The primarypurpose of the database is for use in JPL’s Team X architecturestudies to inform cost estimates of a spacecraft bus which fitsthe customer’s technical requirements for their payload andmission. Customer needs are often unique and don’t alignperfectly with an off-the-shelf commercial spacecraft bus, whichmotivates the need to develop a cost model across the continuoustechnical parameter space.Al’s Bus Cost Distribution Estimator (ABCDE) uses Gaussianprocess regression (GPR) to predict commercial Smallsat spacecraftbus cost based on a subset of a customer’s technicalrequirements (payload mass, payload power, delta V, pointingcontrol, and downlink rate). GPR is implemented in ABCDE asa Bayesian method which fits an implied multivariate regressionon the technical parameters and uses kriging to intentionally“overfit” the residuals. Overfitting the residuals allows costestimates to collapse in uncertainty closer to the data pointswhile maintaining larger uncertainty intervals in regions of parameterspace with fewer data records. The data used to fit thismodel is sensitive and represents cost estimates for off-the-shelfcommercial buses. GPR simultaneously protects the sensitivityof the database and uses the sparse nature of the database toaccount for uncertainty in cost in a useful way. For a givenset of customer technical requirements, the tool provides a costestimate distribution, the percentiles of which can be interpretedas a confidence level of finding a commercial bus under a specifiedcost cap. ABCDE dramatically pushes the boundaries ofspacecraft cost estimation models due to its Bayesian methodology(accounting for the maximum uncertainty in the underlyingregression), the mathematically advanced kriging methodology,and the novelty of its application in Team X architecture tradestudies.

Austin, Alex↗
NASA NTRS2001

Hearing loss in space

BACKGROUND: Temporary and, in some cases, permanent hearing loss has been documented after long-duration spaceflights. METHODS: We examined all existing published data on hearing loss after space missions to characterize the losses. RESULTS: Data from Russian missions suggest that the hearing loss, when it occurs, affects mainly mid to high frequencies and that using hearing protection often might prevent the loss. Several significant questions remain about hearing loss in space. While the hearing loss has been presumed to be noise-induced, no clear link has been established between noise exposure and hearing loss during spaceflight. In one documented case of temporary hearing loss from the Shuttle-Mir program, the pattern of loss was atypical for a noise-induced loss. Continuous noise levels that have been measured on the Mir and previous space stations, while above engineering standards, are not at levels usually associated with hearing loss in ground-based studies (which have usually been limited to 8-10 h exposure periods). Attempts to measure hearing in space using threshold-based audiograms have been unsuccessful in both the American and Russian programs due to noise interference with the measurements. CONCLUSIONS: The existing data highlight the need for reliable monitoring of both hearing and noise in long-duration spaceflight.

manned↗