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At least 163 records · Page 9
All sourcesNASA NTRSDOE OSTI
NASA NTRS2018

Monitoring Astronaut Health with DNA Sequencing

In recent years microbe a plethora of microbe populations have been identified onboard the ISS (International Space Station). Approaches for real-time tracking of microbes for routine housekeeping and food/water safety monitoring will be critical for mission safety and crew health on future longer duration missions to the Moon or Mars. This work is a proof-of-concept study demonstrating an end-to-end phylogenetic identification and full genome sequencing effort of multiple microbial populations. Our methodology utilized the ISS flight-certified WetLab-2 molecular toolbox and the Biomolecule Sequencer projects for real-time end-to-end on-orbit microbial biological samples processing and molecular analysis with real time results generated utilizing only field "offline" analytic software. For this experiment we colony-cultured several ISS isolated microorganisms before generation of the pre-sequencing library via the automated VolTRAX device which enabled high library turnover with little wet-bench activity or potential future costly astronaut time. The pre-sequencing library is diluted in loading buffer and injected into the MinION sample port, drawn into the nanopore window by capillary action, and sequenced using the MinKnown. 16S and full genome alignment, nucleotide matching, gene identification, and phylogenetic sorting was accomplished utilizing the Epi2me software and the offline NCBI Blast viral, microbiome, and human somatic databases. In short, the methodologies developed herein replace the myriad of specific, often highly targeted microbiological tests used in the clinical laboratory, which would be difficult if not impossible to currently implement aboard the ISS or in deep space, with a single metagenomics test.

genomics↗
NASA NTRSDate not supplied

Wind Tunnel Experiment of Microjet-based Flow Control on a Multi-Element High-Lift Airfoil

A wind tunnel model was designed, manufactured, and tested to evaluate the potential of active aerodynamic flow control for multi-element airfoils. The active flow control system involves so-called microjets –small, low momentum, normal to the surface jets located near the trailing edge of the flap –for controlling the lift and improving the aerodynamic performance characteristics of airplane high-lift systems. The configuration selected for this test is the NLR7301 two-element airfoil and it was tested in the Oran W. Nicks Low-Speed Wind Tunnel at Texas A&M University at a chord Reynolds number of 2.0 million and Machnumber of 0.10. This paper presents wind tunnel results for the NLR7301 in the Flap 20 and Flap 30 configurations. The wind tunnel results include surface pressure distributions, lift and pitching moment, and flow visualizations.The results of this experiment validate the effectiveness of the microjet with regards to control of lift in the linear regime for multi-element airfoils.

ARMD↗
NASA NTRSDate not supplied

Timed Collections in the NASA Cosmic Dust Aircraft Collected Particle Collection Including Previous Collectors

The NASA Cosmic Dust Collections includes a collection of interplanetary particles gathered using high-altitude aircraft (the Aircraft Collected Particle collection, or ACP). These particles include cosmic-origin particles as well as particles of terrestrial origin such as volcanic ash, solid rocket motor effluent, and terrestrial dust. The cosmic-origin dust comes from two principal sources - material originating from the diffuse interplanetary background which are uncoupled from the orbits of larger bodies, and cometary-origin particles which are dynamically coupled with the orbits of their parent bodies to form dust streams. These dust stream particles generate short-lived, annual meteor showers and are important because, if they can be identified as originating from a given dust stream, they can be studied in the laboratory as samples of a specific comet. Collecting these particles requires dedicated ACP flights which are timed to coincide with a specific meteor shower. These “timed collections” hold the promise of providing samples from a suite of comets including those never visited by spacecraft [1-3]. This abstract describes a recent (Dec 2020) timed collection attempt, lists previous timed collections with collected particles available for request from the NASA Cosmic Dust Collections, as well as listing ACP collectors which were collected when no meteor showers were active for potential use as control samples.

cosmic dust↗
NASA NTRSDate not supplied

Physics-Guided Deep Learning for Complex System Health Management and Decision Making

The landscape of complex engineered systems is rapidly evolving, from smart manufacturing facilities to next-generation transportation vehicles. As these systems become increasingly sophisticated and interconnected, the need for advanced health management systems grows ever more critical. These systems must go beyond simple monitoring, actively predicting potential failures before they occur. This paradigm shift from fixed maintenance schedules to condition-based predictions is key to optimizing system performance, enhancing safety, and paving the way for autonomous decision-making across various industries. Whether in industrial processes, energy systems, or advanced transportation, the ability to anticipate and prevent failures is becoming a cornerstone of operational excellence. To accurately predict the future health of any complex system, knowledge of its current health state and future operational conditions is essential. Recent advancements in data-driven algorithms have generated growing interest in artificial intelligence for industrial applications. However, the limitations of pure data-driven methods, particularly in industries where data acquisition is costly and limited, have become apparent. This has led to a focus on blending physics with data-driven algorithms, mitigating the drawbacks of both approaches while emphasizing their respective advantages. This research proposes a novel framework for integrating physics-based performance models with deep learning algorithms for the prognostics of complex safety-critical systems. In this approach, physics-based models serve as a blueprint, capturing fundamental system behaviors, while deep learning algorithms, leveraging real-world sensor data, fill in gaps and identify subtle patterns indicative of potential problems. This hybrid methodology, utilizing techniques such as Physics-Informed Neural Networks (PINNs), offers a powerful solution for predicting system health. By fusing domain knowledge with data-driven insights, this approach promises more accurate, adaptable, and reliable models for health prediction. The resulting framework is versatile, applicable across various sectors including aerospace, manufacturing, and energy systems, ultimately contributing to safer, more efficient operations in our increasingly complex technological landscape.

Diagnostics↗
NASA NTRS1999

Quantitative Method of Measuring Metastatic Activity

The metastatic potential of tumors can be evaluated by the quantitative detection of urokinase and DNA. The cell sample selected for examination is analyzed for the presence of high levels of urokinase and abnormal DNA using analytical flow cytometry and digital image analysis. Other factors such as membrane associated uroldnase, increased DNA synthesis rates and certain receptors can be used in the method for detection of potentially invasive tumors.

Morrison, Dennis R.↗
NASA NTRS2011

Characterization of Volume F Trash from Four Recent STS Missions: Weights, Categorization, Water Content

The fate of space-generated solid wastes, including trash, for future missions is under consideration by NASA. Several potential treatment options are under consideration and active technology development. Potential fates for space-generated solid wastes are: Storage without treatment; storage after treatment(s) including volume reduction, water recovery, sterilization, and recovery plus recycling of waste materials. Recycling might be important for partial or full closure scenarios because of the prohibitive costs associated with resupply of consumable materials. For this study, we determined the composition of trash returned from four recent STS missions. The trash material was 'Volume F' trash and other trash, in large zip-lock bags, that accompanied the Volume F trash. This is the first of two submitted papers on these wastes. This one will cover trash content, weight and water content. The other will report on the microbial Characterization of this trash. STS trash was usually made available within 2 days of landing at KSC. The Volume F bag was weighed, opened and the contents were catalogued and placed into one of the following categories: food waste (and containers), drink containers, personal hygiene items - including EVA maximum absorbent garments (MAGs)and Elbow packs (daily toilet wipes, etc), paper, and packaging materials - plastic firm and duct tape. Trash generation rates for the four STS missions: Total wet trash was 0.602 plus or minus 0.089 kg(sub wet) crew(sup -1) d(sup -1) containing about 25% water at 0.154 plus or minus 0.030 kg(sub water) crew(sup -1) d(sup -1) (avg plus or minus stdev). Cataloguing by category: personal hygiene wastes accounted for 50% of the total trash and 69% of the total water for the four missions; drink items were 16% of total weight and 16% water; food wastes were 22% of total weight and 15% of the water; office waste and plastic film were 2% and 11% of the total waste and did not contain any water. The results can be used by NASA to determine requirements and criteria for Waste Management Systems on future missions.

Strayer, Richard F.↗
NASA NTRS2011

Use of Dual-Polarization Radar Variables to Assess Low-Level Wind Shear in Severe Thunderstorm Near-storm Environments in the Tennessee Valley

The upgrade of the National Weather Service (NWS) network of S ]band dual-polarization radars is currently underway, and the incorporation of polarimetric information into the real ]time forecasting process will enhance the forecaster fs ability to assess thunderstorms and their near ]storm environments. Recent research has suggested that the combination of polarimetric variables differential reflectivity (ZDR) and specific differential phase (KDP) can be useful in the assessment of low level wind shear within a thunderstorm. In an environment with strong low ]level veering of the wind, ZDR values will be largest along the right inflow edge of the thunderstorm near a large gradient in horizontal reflectivity (indicative of large raindrops falling with a relative lack of smaller drops), and take the shape of an arc. Meanwhile, KDP values, which are proportional to liquid water content and indicative of a large number of smaller drops, are maximized deeper into the forward flank precipitation shield than the ZDR arc as the smaller drops are being advected further from the updraft core by the low level winds than the larger raindrops. Using findings from previous work, three severe weather events that occurred in North Alabama were examined in order to assess the utility of these signatures in determining the potential for tornadic activity. The first case is from October 26, 2010, where a large number of storms indicated tornadic potential from a standard reflectivity and velocity analysis but very few storms actually produced tornadoes. The second event is from February 28, 2011, where tornadic storms were present early on in the event, but as the day progressed, the tornado threat transitioned to a high wind threat. The third case is from April 27, 2011, where multiple rounds of tornadic storms ransacked the Tennessee Valley. This event provides a dataset including multiple modes of tornadic development, including QLCS and supercell structures. The overarching goal of examining these three events is to compare dual ]polarization features from this larger dataset to previous work and to determine if these signatures can be a useful indication of the potential for tornadic activity associated with the amount of low ]level wind shear in the near ]storm environment.

Crowe, Christina C.↗
NASA NTRS2004

Active Flow Control Activities at NASA Langley

NASA Langley continues to aggressively investigate the potential advantages of active flow control over more traditional aerodynamic techniques. This paper provides an update to a previous paper and describes both the progress in the various research areas and the significant changes in the NASA research programs. The goals of the topics presented are focused on advancing the state of knowledge and understanding of controllable fundamental mechanisms in fluids as well as to address engineering challenges. An organizational view of current research activities at NASA Langley in active flow control as supported by several projects is presented. On-center research as well as NASA Langley funded contracts and grants are discussed at a relatively high level. The products of this research are to be demonstrated either in bench-top experiments, wind-tunnel investigations, or in flight as part of the fundamental NASA R&D program and then transferred to more applied research programs within NASA, DOD, and U.S. industry.

Anders, Scott G.↗
NASA NTRS2020

Forecasting Rates of Volcanic Activity on Terrestrial Exoplanets

Similar to the planets and moons in our solar system, terrestrial exoplanets may be shaped by volcanism and tectonics. The magnitudes and rates of geological activity on terrestrial exoplanets will be intimately linked to their sizes and internal heating rates, and can either facilitate, or preclude, the existence of habitable environments. In order to place bounds on the potential for such activity, we estimate total internal heating rates for 52 exoplanets, with masses and radii up to ~ 8M(sub E) and 2R(sub E), respectively, assuming that internal heating is drawn from both radiogenic and tidal sources. We then compare these internal heating rates to those of the bodies in our solar system in an attempt to constrain the rates of volcanic activity on extrasolar worlds. We find that all of the exoplanets surveyed are likely to exhibit volcanic activity at their surfaces. We also find that at least 25% of the of the planets in our study may be extrasolar ocean worlds, the majority of which may contain internal oceans beneath layers of surface ice. These planets may be similar in structure to the icy moons of the giant planets and may have persistent cryovolcanic activity at their surfaces. Volcanic activity on exoplanets could be detected by next-generation space telescopes in transit spectra. In the case of planets with densities and/or effective temperatures that are consistent with H2O-rich compositions, spectral identification of excess water vapor and other molecules that are explosively vented into space during cryovolcanic eruptions could serve as a way to infer the presence of subsurface oceans, and therefore indirectly assess their habitability. Considering the implications for habitability, our results suggest that characterizing Earth-like exoplanets in terms of the potential for geological activity at their surfaces should be a priority in the coming years.

Lynnae C Quick↗
NASA NTRS2020

Forecasting Rates of Volcanic Activity on Terrestrial Exoplanets and Implications for Cryovolcanic Activity on Extrasolar Ocean Worlds

Like the planets and moons in our solar system, the surfaces of terrestrial exoplanets may be shaped by volcanic activity. The magnitudes and rates of volcanic activity on terrestrial exoplanets will be intimately linked to their sizes and internal heating rates and can either facilitate or preclude the existence of habitable environments. In order to place bounds on the potential for such activity, we estimate total internal heating rates for 53 exoplanets with masses and radii up to∼8M⊕and 2R⊕, respectively, assuming that internal heating is drawn from both radiogenic and tidal sources. We then compare these internal heating rates to those of the planets and moons in our solar system in an attempt to constrain the expected rates of volcanic activity on these extrasolar worlds. We find that all 53 of the exoplanets surveyed are likely to have volcanic activity at their surfaces, and that at least 26% of these planets may be extrasolar ocean worlds. The majority of these ocean worlds may be similar in structure to the icy moons of the giant planets, having internal oceans beneath layers of surface ice. If so, these planets may exhibit cryovolcanism (i.e., icy volcanism)at their surfaces. Recent studies have shown that extrasolar volcanism could be detected by high-resolution spectrographs on existing ground-based telescopes. In the case of planets with densities and/or effective temperatures that are consistent with H2O-rich compositions, spectral identification of excess water vapor and other molecules that are explosively vented into space during cryovolcanic eruptions could serve as a way to infer the presence of subsurface oceans, and therefore indirectly assess their habitability. Considering the implications for habitability, our results suggest that continued characterization of terrestrial exoplanets in terms of their potential for volcanic activity should be a priority in the coming years.

Lynnae C Quick↗
NASA NTRS2002

Snapshot of Active Flow Control Research at NASA Langley

NASA Langley is aggressively investigating the potential advantages of active flow control as opposed to more traditional aerodynamic techniques. Many of these techniques will be blended with advanced materials and structures to further enhance payoff. Therefore a multi-disciplinary approach to technology development is being attempted that includes researchers from the more historical disciplines of fluid mechanics. acoustics, material science, structural mechanics, and control theory. The overall goals of the topics presented are focused on advancing the state of knowledge and understanding of controllable fundamental mechanisms in fluids rather than on specific engineering problems. An organizational view of current research activities at NASA Langley in active flow control as supported by several programs such as the Morphing Project under Breakthrough Vehicle Technologies Program (BVT). the Ultra-Efficient Engine Technology Program (UEET), and the 21st Century Aircraft Technology Program (TCAT) is presented. On-center research as well as NASA Langley funded contracts and grants are discussed at a relatively high level. The products of this research, as part of the fundamental NASA R and D (research and development) program. will be demonstrated as either bench-top experiments, wind-tunnel investigations, or in flight tests. Later they will be transferred to more applied research programs within NASA, DOD (Department of Defense), and U.S. industry.

Washburn, A. E.↗
NASA NTRS2016

Active Full-Shell Grazing-Incidence Optics

MSFC has a long history of developing full-shell grazing-incidence x-ray optics for both narrow (pointed) and wide field (surveying) applications. The concept presented in this paper shows the potential to use active optics to switch between narrow and wide-field geometries, while maintaining large effective area and high angular resolution. In addition, active optics has the potential to reduce errors due to mounting and manufacturing lightweight optics. The design presented corrects low spatial frequency error and has significantly fewer actuators than other concepts presented thus far in the field of active x-ray optics. Using a finite element model, influence functions are calculated using active components on a full-shell grazing-incidence optic. Next, the ability of the active optic to effect a change of optical prescription and to correct for errors due to manufacturing and mounting is modeled.

Full-shell↗
NASA NTRS2012

Satellite-based Assessment of Climate Controls on US Burned Area

Climate regulates fire activity through the buildup and drying of fuels and the conditions for fire ignition and spread. Understanding the dynamics of contemporary climate-fire relationships at national and sub-national scales is critical to assess the likelihood of changes in future fire activity and the potential options for mitigation and adaptation. Here, we conducted the first national assessment of climate controls on US fire activity using two satellite-based estimates of monthly burned area (BA), the Global Fire Emissions Database (GFED, 1997 2010) and Monitoring Trends in Burn Severity (MTBS, 1984 2009) BA products. For each US National Climate Assessment (NCA) region, we analyzed the relationships between monthly BA and potential evaporation (PE) derived from reanalysis climate data at 0.5 resolution. US fire activity increased over the past 25 yr, with statistically significant increases in MTBS BA for entire US and the Southeast and Southwest NCA regions. Monthly PE was strongly correlated with US fire activity, yet the climate driver of PE varied regionally. Fire season temperature and shortwave radiation were the primary controls on PE and fire activity in the Alaska, while water deficit (precipitation PE) was strongly correlated with fire activity in the Plains regions and Northwest US. BA and precipitation anomalies were negatively correlated in all regions, although fuel-limited ecosystems in the Southern Plains and Southwest exhibited positive correlations with longer lead times (6 12 months). Fire season PE in creased from the 1980s 2000s, enhancing climate-driven fire risk in the southern and western US where PE-BA correlations were strongest. Spatial and temporal patterns of increasing fire season PE and BA during the 1990s 2000s highlight the potential sensitivity of US fire activity to climate change in coming decades. However, climatefire relationships at the national scale are complex, based on the diversity of fire types, ecosystems, and ignition sources within each NCA region. Changes in the seasonality or magnitude of climate anomalies are therefore unlikely to result in uniform changes in US fire activity.

Morton, D. C.↗
NASA NTRSDate not supplied

A Machine Learning Ready Dataset of Acoustic Power Maps for Detection of Active Region Emergence

The development of an accurate forecast for solar eruptive activity has become increasingly important in order to prevent any potential impact on activities in space and the Earth's environment. It is therefore crucial to detect active regions before they appear on the solar surface and create early warning capabilities for upcoming Space Weather disturbances. In this work, 9TB of solar data (SDO/HMI dopplergrams, magnetograms and continuum intensity maps) involving the emergence of 61 NOAA solar active regions since 2010 were processed using the NASA HECC capabilities. An acoustic power maps time-series dataset was created (for four different frequency ranges and processed to take into account the solar sphere geometric effect ) which can be used for understanding the dynamics of the solar surface and train a variety of ML models. The calculated acoustic power maps carry precursor information associated with the decrease in continuum intensity on the solar surface, verifying older helioseismology research. Our results show that a Long Short-Term Memory (LSTMs) model, with a modest layer depth and the right hyperparameters tuned, when trained on this solar acoustic power maps dataset can predict without false negatives a drop in intensity (associated with the emergence of the active region), up to 18 hours in advance.

SMD↗
NASA NTRS2007

NASA's Potential Contributions to Avalanche Forecasting Using Active and Passive Microwave Measurements

This Candidate Solution is based on using active and passive microwave measurements acquired from NASA satellites to improve USDA (U.S. Department of Agriculture) Forest Service forecasting of avalanche danger. Regional Avalanche Centers prepare avalanche forecasts using ground measurements of snowpack and mountain weather conditions. In this Solution, range of the in situ observations is extended by adding remote sensing measurements of snow depth, snow water equivalent, and snowfall rate acquired by satellite missions that include Aqua, CloudSat, future GPM (Global Precipitation Measurement), and the proposed SCLP (Snow and Cold Land Processes). Measurements of snowpack conditions and time evolution are improved by combining the in situ and satellite observations with a snow model. Recurring snow observations from NASA satellites increase accuracy of avalanche forecasting, which helps the public and the managers of public facilities make better avalanche safety decisions.

Blonski, Slawomir↗
NASA NTRS2021

Leveraging NASA Soil Moisture Active Passive for Assessing Fire Susceptibility and Potential Impacts over Australia and California

Wildfires are a major concern around the globe because of the immediate impact they have on people's lives, local ecosystems, and the environment. Soil moisture is one of the most important factors that influences wildfire occurrences and spread. However, it is also one of the most challenging hydrological variables to measure routinely and accurately. Therefore, soil moisture is significantly underutilized in operational wildfire risk applications. Thus, the aim here is to use a well-established operational soil moisture product to isolate the soil moisture-fire relationship and assess the utility of using soil moisture as a leading indicator of potential fire risk. We evaluated the value of remotely-sensed soil moisture observations from the Soil Moisture Active Passive (SMAP) sensor for monitoring and predicting fire risk in Australia and California. We quantified the relationship between observed fire activity and soil moisture conditions and analyzed the soil moisture conditions for two extreme fire events. Our findings show that fire activity is strongly associated with soil moisture anomalies. Lagged correlation analysis demonstrated that a remote-sensing based soil moisture product could predict fire activity with a 1-2 month lead-time. Soil moisture anomalies consistently decreased in the months preceding fire occurrence, often from normal to drier conditions, according to a spatiotemporal analysis of soil moisture in two extreme fire events. Overall, our findings indicate that soil moisture conditions prior to large wildfires can aid in their prediction and operational satellite-based soil moisture products such as the one used here have real value for supporting wildfire susceptibility and impacts.

Nazmus Sazib↗
NASA NTRS2004

Non-Additive Voltametric Currents From a Mixture of Two, Three and Four Redox-Active Compounds and Electroanalytical Implications

We have published recently the effect of dissimilar diffusion coefficients on the size of the voltammetric waves from a mixture of two redox-active compounds. Similarly, at the potential range where three redox-active species, decamethylferrocene (dMeFc), ferrocene (Fc) and N-methylphenothiazine (MePTZ), are oxidized simultaneously with rates controlled by linear diffusion, electrogenerated radicals diffusing outwards from the electrode react with the original species diffusing towards the electrode from the bulk; thus, Fc(+) reacts with dMeFc producing Fc and dMeFc(+), while MePTZ(+) reacts both with dMeFc producing MePTZ and dMeFc(+), and with Fc producing MePTZ and Fc(+). These reactions replace dMeFc with Fc at the second plateau, and both dMeFc and Fc with MePTZ at the third plateau. Since the diffusion coefficients of the three species are not equal, the mass-transfer limited currents of the second and the third oxidation wave plateaus change by approx. 10%. Numerical simulations of the experimental voltamograms support this mechanism. Similar results were also obtained for a mixture of four redoxactive compounds. The implications of this non-additive nature of currents on: (a) the use of internal voltammetric standards for quantitative analysis of a mixture of redox-active compounds; and, (b) the half wave potentials (E1/2) of the 2nd, 3rd and 4th waves for qualitative analysis, will be discussed.

Dass, Amala↗