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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 163 records · Page 9

Meteorology of Jupiter's Equatorial Hot Spots and Plumes from Cassini

We present an updated analysis of Jupiter's equatorial meteorology from Cassini observations. For two months preceding the spacecraft's closest approach, the Imaging Science Subsystem (ISS) onboard regularly imaged the atmosphere. We created time-lapse movies from this period in order to analyze the dynamics of equatorial hot spots and their interactions with adjacent latitudes. Hot spots are relatively cloud-free regions that emit strongly at 5 lm; improved knowledge of these features is crucial for fully understanding Galileo probe measurements taken during its descent through one. Hot spots are quasistable, rectangular dark areas on visible-wavelength images, with defined eastern edges that sharply contrast with surrounding clouds, but diffuse western edges serving as nebulous boundaries with adjacent equatorial plumes. Hot spots exhibit significant variations in size and shape over timescales of days and weeks. Some of these changes correspond with passing vortex systems from adjacent latitudes interacting with hot spots. Strong anticyclonic gyres present to the south and southeast of the dark areas appear to circulate into hot spots. Impressive, bright white plumes occupy spaces in between hot spots. Compact cirrus-like 'scooter' clouds flow rapidly through the plumes before disappearing within the dark areas. These clouds travel at 150-200 m/s, much faster than the 100 m/s hot spot and plume drift speed. This raises the possibility that the scooter clouds may be more illustrative of the actual jet stream speed at these latitudes. Most previously published zonal wind profiles represent the drift speed of the hot spots at their latitude from pattern matching of the entire longitudinal image strip. If a downward branch of an equatorially-trapped Rossby wave controls the overall appearance of hot spots, however, the westward phase velocity of the wave leads to underestimates of the true jet stream speed.

Jupitor's Equatorial Zone↗

Seeing Earth Through the Eyes of an Astronaut

The Human Exploration Science Office within the ARES Directorate has undertaken a new class of handheld camera photographic observations of the Earth as seen from the International Space Station (ISS). For years, astronauts have attempted to describe their experience in space and how they see the Earth roll by below their spacecraft. Thousands of crew photographs have documented natural features as diverse as the dramatic clay colors of the African coastline, the deep blues of the Earth's oceans, or the swirling Aurora Borealis of Australia in the upper atmosphere. Dramatic recent improvements in handheld digital single-lens reflex (DSLR) camera capabilities are now allowing a new field of crew photography: night time-lapse imagery.

Dawson, Melissa↗

Lab-On-Chip Clinorotation System for Live-Cell Microscopy Under Simulated Microgravity

Cells in microgravity are subject to mechanical unloading and changes to the surrounding chemical environment. How these factors jointly influence cellular function is not well understood. We can investigate their role using ground-based analogues to spaceflight, where mechanical unloading is simulated through the time-averaged nullification of gravity. The prevailing method for cellular microgravity simulation is to use fluid-filled containers called clinostats. However, conventional clinostats are not designed for temporally tracking cell response, nor are they able to establish dynamic fluid environments. To address these needs, we developed a Clinorotation Time-lapse Microscopy (CTM) system that accommodates lab-on- chip cell culture devices for visualizing time-dependent alterations to cellular behavior. For the purpose of demonstrating CTM, we present preliminary results showing time-dependent differences in cell area between human mesenchymal stem cells (hMSCs) under modeled microgravity and normal gravity.

Yew, Alvin G.↗

Lab-On-Chip Clinorotation System for Live-Cell Microscopy Under Simulated Microgravity

Cells in microgravity are subject to mechanical unloading and changes to the surrounding chemical environment. How these factors jointly influence cellular function is not well understood. We can investigate their role using ground-based analogues to spaceflight, where mechanical unloading is simulated through the time-averaged nullification of gravity. The prevailing method for cellular microgravity simulation is to use fluid-filled containers called clinostats. However, conventional clinostats are not designed for temporally tracking cell response, nor are they able to establish dynamic fluid environments. To address these needs, we developed a Clinorotation Time-lapse Microscopy (CTM) system that accommodates lab-on- chip cell culture devices for visualizing time-dependent alterations to cellular behavior. For the purpose of demonstrating CTM, we present preliminary results showing time-dependent differences in cell area between human mesenchymal stem cells (hMSCs) under modeled microgravity and normal gravity.

Yew, Alvin G.↗

Persistence Mapping Using EUV Solar Imager Data

We describe a simple image processing technique that is useful for the visualization and depiction of gradually evolving or intermittent structures in solar physics extreme-ultraviolet imagery. The technique is an application of image segmentation, which we call "Persistence Mapping," to isolate extreme values in a data set, and is particularly useful for the problem of capturing phenomena that are evolving in both space and time. While integration or "time-lapse" imaging uses the full sample (of size N ), Persistence Mapping rejects (N - 1)/N of the data set and identifies the most relevant 1/N values using the following rule: if a pixel reaches an extreme value, it retains that value until that value is exceeded. The simplest examples isolate minima and maxima, but any quantile or statistic can be used. This paper demonstrates how the technique has been used to extract the dynamics in long-term evolution of comet tails, erupting material, and EUV dimming regions.

Thompson, B. J.↗

Scaling Evaluation of Ice-Crystal Icing on a Modern Turbofan Engine in PSL Using the COMDES-MELT Code

This paper presents preliminary ice-crystal icing (ICI) altitude scaling evaluation results of a Honeywell Uncertified Research Engine (HURE) that was tested in the NASA Glenn Research Center Propulsion Systems Laboratory (PSL) during January of 2018. This engine geometry features a hidden core design to keep the core less exposed. The engine was fitted with internal video cameras to observe various ice buildup processes at multiple selected locations within the engine core flow path covering the fan stator, the splitter-lip/shroud/strut, and the high pressure compressor (HPC) variable inlet guide vane (IGV) regions. The potential ice accretion risk was pre-determined to occur by using NASA’s in-house 1D Engine Icing Risk assessment code, COMDES-MELT. The code was successful in predicting the risk of ice accretion in adiabatic regions like the fan-stator of the HURE at specific engine operating points. However at several operating points during the test, liquid water was observed running along the shroud toward the variable IGV of the HPC regions with an air temperature well below freezing, thus no particle melting could have occurred due to heating from the air alone. It was reasoned that other sources of heat were present in that region. To account for these heat sources the inlet total temperature was adjusted to give a wet bulb temperature of 24 F below the standard minimum wet bulb temperature of 492 R to allow ice to accrete in the splitter-lip/shroud/strut region, which was determined from a reference case where hard ice was observed in that region. With that adjustment the COMDES-MELT code was successful in providing operating points where there was a risk of ice accretion during the test campaign. In addition to calculating possible conditions at different selected lower altitudes, simulations were run to determine potential inlet conditions that could lead to ice-crystal accretion along the prescribed stations where the cameras were available. From there, scaled test conditions were determined by best matching the following three icing related parameters of the reference condition: (1) the local air total wet bulb temperature, (2) the local ice crystal cloud melt ratio and (3) the engine fan face ice/water to air mass flux ratio of the ice crystal cloud. Instantaneous images taken from the time-lapsed movies of ice buildup were used along with the relevant thermodynamic data of air, water vapor and local icing condition to help evaluate how closely the proposed altitude scaling method could be used in ground based test facility to duplicate selected reference ICI features observed at specific location inside this engine at different scale altitudes. Discussions on observed limitation for engine icing scaling application from this test campaign and needed improvement are provided. A scaling test procedure to help identify potential ICI risk conditions and possible ice accretion locations of a new turbofan engine is evaluated in PSL.

Engine Testing in PSL↗

Building a Bilingual Google Earth Engine Dashboard to Increase Accessibility to Long-term Time Series Remote Sensing Data for Monitoring Saline System Changes in Chile’s Atacama Desert

Saline systems, consisting of salt flats, ponds, and marshes, provide vital water resources to wildlife and communities in northern Chile’s Atacama Desert, one of the driest regions in the world. Mining is extensive in the Atacama, which contains 30% of the world’s lithium reserves and is abundant in potassium and boron. The groundwater that feeds into salt marshes and ponds is extracted in large volumes for mining operations, limiting the availability of water for ecosystems. However, identifying long-term and large-scale environmental impacts from local lithium mining on the saline systems is limited by region inaccessibility and terrain variability. Open access satellite imagery and cloud computing technology has made studying Atacama saline systems feasible and allowed for collaboration across different agencies and countries. The NASA DEVELOP Program partnered with Chile’s la Universidad de La Serena and Servicio Nacional de Geología y Minería (SERNAGEOMIN) to create the Saline Analysis Tool (SalT) in Google Earth Engine (GEE). SalT is used to analyze the extent and distribution of remote saline systems in the Atacama from 1986 to the present day. The tool filters Landsat 5 Thematic Mapper (TM) and Landsat 8 Operational Land Imager (OLI) data from GEE’s data catalog and creates a single composite image per year for analysis. Additional output analyses include land cover classification, Normalized Difference Vegetation Index (NDVI) and Normalized Difference Water Index (NDWI) raster images that can be displayed on the map interface or exported. The tool can also generate time-lapse videos and charts displaying NDVI, NDWI, and land cover over time. A key feature of the tool is the use of a bilingual graphical user interface to make analysis accessible and customizable to different users’ needs—SalT provides options to select an analysis area, analysis time period, and outputs to display or export. The tool also incorporates new Earth observations as they are added to GEE’s catalog. The ability to easily visualize and analyze long-term remote sensing imagery will enable SERNAGEOMIN and la Universidad de la Serena to continually monitor changes in these saline systems and inform future land management policy.

NASA DEVELOP↗

Electric Six Degree of Freedom Installation Timelapse (Six Degree of Freedom Dynamic Test System)

The Six-degree-of-freedom Dynamic Test System (SDTS) is a short-range real-time motion based testing platform. Its primary use at NASA/JSC has been for development and qualification testing of docking systems, robotic assisted berthing mechanisms, and dynamic attachment systems. The SDTS is a closed-loop force feedback system that can simulate on-orbit contact dynamics between two vehicles utilizing the actual mechanical interfaces for testing. The facility is controlled by interconnected computers running real-time simulation software that takes measured contact forces, integrates the equations of motion in real time, and provide those states back into the motion table. This infrastructure can also be used for non-mating applications such as relative position sensor testing/evaluations. The SDTS facility provides a superstructure for mounting test articles, multiple test sensors, an intercom network for voice communications, and a synchronized timing system for data acquisition that includes HD video. This time-lapse video shows the buildup and testing of a modern electric actuation system created by Mikrolar, Inc. at the Johnson Space Center. This motion base will replace the current hydraulic actuator system, which is been in use since the 1970s, for all-future NASA testing. Once the system goes through customization to provide JSC’s unique closed-loop environment, the facility will help certify docking system and attach mechanisms on the ground before we send the first woman and the next man to the lunar surface

hexapod↗

U.S. Spacesuit Knowledge Capture – Chronicling Spacesuit Design for the Future

With less than 4 years until the United States is scheduled to land the first woman and next man on the Moon, NASA is leveraging 60 years of experience to build a spacesuit to assist in the success of this and future human space exploration missions. This experience comes from the achievements of retired and employed spacesuit experts, innovations that were conceived from existing ideas and inventions, and a plethora of archived knowledge. The U.S. Spacesuit Knowledge Capture (SKC) Program’s primary function is to capture, archive, and share current and legacy spacesuit-related knowledge with scientists, engineers, and technicians. To capture valuable spacesuit-related knowledge, the program uses various methods that have included hosting and recording classroom and online courses, workshops, and vignettes, and preserving thousands of legacy spacesuit-related files. In 2019, the SKC Program added to its role when it began coordinating the electronic recording of the new spacesuits’ buildup. This new, next-generation spacesuit is named the Exploration Extravehicular Mobility Unit (xEMU) and is a compilation of many components. As each component is tested and assembled into the suit, the SKC Program is chronicling this buildup using high-speed video production and photography that includes time-lapsed images. To complement the recording of the components, the SKC Program plans to record and photograph the design verification testing. In 2020, the SKC Program was given the initiative to research and identify the custodianship of historical spacesuit equipment that resides within the Crew and Thermal Systems Division. These archives will be added to the SKC Program’s expansive archived collection of spacesuit-related knowledge that represents over 5 decades of spacesuit legacy from the Apollo era to the pursuit of Mars and beyond. This paper describes the electronic documentation of the xEMU’s buildup and identifies the SKC Program’s 2020 accomplishments.

Cinda Chullen↗

U.S. Spacesuit Knowledge Capture – Chronicling Spacesuit Design for the Future

With less than 4 years until the United States is scheduled to land the first woman and next man on the Moon, NASA is leveraging 60 years of experience to build a spacesuit to assist in the success of this and future human space exploration missions. This experience comes from the achievements of retired and employed spacesuit experts, innovations that were conceived from existing ideas and inventions, and a plethora of archived knowledge. The U.S. Spacesuit Knowledge Capture (SKC) Program’s primary function is to capture, archive, and share current and legacy spacesuit-related knowledge with scientists, engineers, and technicians. To capture valuable spacesuit-related knowledge, the program uses various methods that have included hosting and recording classroom and online courses, workshops, and vignettes, and preserving thousands of legacy spacesuit-related files. In 2019, the SKC Program added to its role when it began coordinating the electronic recording of the new spacesuits’ buildup. This new, next-generation spacesuit is named the Exploration Extravehicular Mobility Unit (xEMU) and is a compilation of many components. As each component is tested and assembled into the suit, the SKC Program is chronicling this buildup using high-speed video production and photography that includes time-lapsed images. To complement the recording of the components, the SKC Program plans to record and photograph the design verification testing. In 2020, the SKC Program was given the initiative to research and identify the custodianship of historical spacesuit equipment that resides within the Crew and Thermal Systems Division. These archives will be added to the SKC Program’s expansive archived collection of spacesuit-related knowledge that represents over 5 decades of spacesuit legacy from the Apollo era to the pursuit of Mars and beyond. This paper describes the electronic documentation of the xEMU’s buildup and identifies the SKC Program’s 2020 accomplishments.

Cinda Chullen↗

Characterizing Antibiotic Resistance in Microgravity Environments

The gram-positive bacterium Staphylococcus aureus and the gram-negative Pseudomonas aeruginosa are two of NASA’s designated “medically important microorganisms” commonly co-isolated from spaceflight environments like the International Space Station (ISS). Prior studies demonstrate evidence of increased virulence and antibiotic resistance of each bacterium when grown as single species in space. “Characterizing Antibiotic Resistance in Microgravity Environments” (CARMEn) is an autonomous 30-day ISS payload experiment probing the phenotypic changes of S. aureus and P. aeruginosa biofilms grown together in microgravity. Phenotypic changes are probed through three parallel experiments measuring Extracellular Matrix (ECM) production, antibiotic tolerance, and RNA expression respectively. The ECM experiment uses time-lapse imaging to collect observational morphological data from biofilms stained with Congo Red and Coomassie Blue, the antibiotic tolerance experiment utilizes E-strip testing once samples return to Earth, and RNA expression is measured through RNAseq of samples treated with RNAProtect® during spaceflight.

Antibiotic resistance↗

Microbial Responses to Radiation at the Single-Cell Level

Exploring the biological effects of deep space radiation is crucial for developing protective protocols for humans traveling beyond Earth’s magnetosphere. Saccharomyces cerevisiae, or budding yeast, is an ideal model organism to study the effects of radiation on eukaryotes as it shares several pathways with humans, including DNA repair mechanisms. Here, we used time-lapse imaging of colony growth on agar plates to monitor the effects of radiation exposure on individual yeast cells and their progeny.

Paola J. Maldonado Martinez↗

Estimating biofuel contaminant concentration from 4D ERT with mixing models

Here, we present the results of a lab-scaled feasibility study to assess the performance of electrical resistivity tomography for detection, characterization, and monitoring of fuel grade ethanol releases to the subsurface. Further, we attempt to determine the concentration distribution of the ethanol from the electrical resistivity tomography data using mixing-models. Ethanol is a renewable fuel source as well as an oxygenate fuel additive currently used to replace the known carcinogen methyl tert-butyl ether; however, ethanol is preferentially biodegraded and a cosolvent. When introduced to areas previously impacted by nonethanol-based fuels, it will facilitate the persistence of carcinogenic fuel compounds like benzene and ethylbenzene, as well as remobilize them to the ground water. These compounds would otherwise be retained in the soil column undergoing active or passive remediation processes such as soil vapor extraction or natural attenuation. Here, we introduce ethanol to a saturated Ottawa sand in a tank instrumented for four-dimensional geoelectrical measurements. Forward model results suggest pure phase ethanol released into a water saturated silica sand should present a detectable target for electrical resistivity tomography relative to a saturated silica sand only. We observe the introduction of ethanol to the closed hydraulic system and subsequent migration over the duration of the experiment. One-dimensional and three–dimensional temporal data are assessed for the detection, characterization, and monitoring of the ethanol release. Results suggest one-dimensional geoelectrical measurements may be useful for monitoring a release, while three-dimensional geoelectrical field imaging would be useful to characterize, monitor, and design effective remediation approaches for an ethanol release, assuming field conditions do not preclude the application of geoelectrical methods. We then attempt to use predictive mixing models to calculate the distribution of ethanol concentration within the measurement domain. For this study we examine four different models: a nested parallel mixing model, a nested cubic mixing model, the complex refractive index model (CRIM), and the Lichtenecker-Rother (L-R) model. The L-R model, modified to include an electrical formation factor geometry term, provided the best agreement with expected EtOH concentrations.

09 BIOMASS FUELS↗

Understanding Subsurface Fracture Evolution Dynamics Using Time‐Lapse Full Waveform Inversion of Continuous Active‐Source Seismic Monitoring Data

Abstract Predicting the behavior, geometry, and flow properties of subsurface fractures remains a challenging problem. Seismic models that can characterize fractures usually suffer from low spatiotemporal resolution. Here, we develop a correlative double‐difference time‐lapse full waveform inversion of continuous active source seismic monitoring data for determining high‐spatiotemporal‐resolution time‐lapse V p models of in‐situ fracture evolution at a shallow contamination site in Wyoming, USA. Assisted by rock physics modeling, we find that (a) rapidly increasing pore pressure initializes and grows the fracture, increasing the porosity slightly (from ∼13.7% to ∼14.6%) in the tight clay formation, thus decreasing V p (∼50 m/s); (b) the fluid injection continues decreasing V p , likely through the introduction of gas bubbles in the injectate; and (c) final V p reductions reach over ∼150 m/s due to a posited ∼4.5% gas saturation. Our results demonstrate that high‐resolution V p changes are indicative of mechanical and fluid changes within the fracture zone during hydrofracturing.

58 GEOSCIENCES↗

Active‐Source Seismic Imaging of Fault Re‐Activation and Leakage: An Injection Experiment at the Mt Terri Rock Laboratory, Switzerland

Abstract We conducted a time‐lapse seismic experiment utilizing automated active seismic source and sensor arrays to monitor a reactivated fault within the Opalinus clay formation at the Mont Terri Rock Laboratory (Switzerland), an analog caprock for geologic carbon storage. A series of six brine injections were conducted into the so‐called Main Fault to reactivate it. Seismic instrumentation in five monitoring boreholes on either side of the fault was used to continuously probe changes in P‐wave travel‐times associated with fault displacement and leakage. We performed time‐lapse travel‐time tomography on five hundred sequential data sets; this revealed a zone of decreased P‐wave velocity, up to 16 m/s, during each injection cycle, followed by a velocity increase during shut‐in. These results demonstrate varying elastic property perturbations, both spatially and temporally, along the fault plane during reactivation. We then interpreted these velocity changes in terms of fault dilation induced by pressurized fluids along the fault.

58 GEOSCIENCES↗

Density fluctuations, homeostasis, and reproduction effects in bacteria

Abstract Single-cells grow by increasing their biomass and size. Here, we report that while mass and size accumulation rates of single Escherichia coli cells are exponential, their density and, thus, the levels of macromolecular crowding fluctuate during growth. As such, the average rates of mass and size accumulation of a single cell are generally not the same, but rather cells differentiate into increasing one rate with respect to the other. This differentiation yields a density homeostasis mechanism that we support mathematically. Further, we observe that density fluctuations can affect the reproduction rates of single cells, suggesting a link between the levels of macromolecular crowding with metabolism and overall population fitness. We detail our experimental approach and the “invisible” microfluidic arrays that enabled increased precision and throughput. Infections and natural communities start from a few cells, thus, emphasizing the significance of density-fluctuations when taking non-genetic variability into consideration.

59 BASIC BIOLOGICAL SCIENCES↗

Time-resolved detectors for quantum ghost imaging

Quantum ghost imaging is a method that utilizes the correlated detection of two photons to generate an image. One photon is detected by an imaging sensor and the other by a single-element bucket detector. The selection of the imaging sensor and its capabilities relative to the bucket detector impact the quality of the ghost images. This work examines a SPAD array and a photocathode detector as imaging sensors for quantum ghost imaging. We discuss how to achieve optimal images using these two technologies. We also demonstrate that these devices are able to generate ghost images at 1Hz frame rates, expanding the technique to biologically relevant time scales.

36 MATERIALS SCIENCE↗

EGS Collab Experiment 2: Shear Stimulation ERT Monitoring Data

This repository contains the electrical resistivity tomography (ERT) monitoring data that was collected before, during, and after shear stimulation attempts were conducted at EGS Collab. These tests were carried out on the SURF 4100 level during Experiment 2 in March, 2022. Flow and stimulation data corresponding to this dataset are available in a different GDR dataset, which is linked below. Also included here are the E4D input files that were used to process the ERT data. E4D is an open source ERT monitoring and inversion code which is linked for use below.

15 GEOTHERMAL ENERGY↗