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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 1,549 records · Page 86
All sourcesNASA NTRSDOE OSTI
NASA NTRSDate not supplied

Reanalysis of Rat Data from Spacelab Life Sciences 2 (SLS-2) to Reveal Research Gaps in Spaceflight Data

Using and analyzing the legacy data obtained in space life sciences missions has the potential to provide researchers a complete picture of the molecular changes associated with space without further experimentation. This project’s objective is to extract, filter, organize, and analyze all Rattus norvegicus data and metadata obtained from Columbia’s Spacelab Life Sciences 2 (SLS-2, STS-58) mission to explore the ways that we can compile information from model organisms, in our case rats, to create a reliable model to understand biological mechanisms in response to these space flight changes. By reusing rare space legacy data coupled with data analysis techniques, we can combine individual preexisting datasets with current ones to gain new, comprehensive insights about the effects of spaceflight on our bodies. Our methods can also lead to the creation of a standardized pipeline that could be applied to other space life science datasets for analysis. In this review, every biological experiment conducted on rats in the SLS-2 Mission was studied with our pipeline to create a new biological library and model that could be used by scientists from around the world to make novel discoveries and develop new hypotheses from this priceless information without the limitation of the costs of spaceflight experimentation.

rats↗
NASA NTRS2022

Understanding the Properties, Wave Drivers, and Impacts of Electron Microburst Precipitation: Current Understanding and Critical Knowledge Gaps

Microbursts are impulsive (~100ms) injections of very energetic to relativistic electrons (energies from a few keV to MeV) into Earth’s atmosphere. Microbursts are important because they may represent a major loss process for the outer radiation belt (Ripoll et al., 2020). Understanding and quantifying the underlying causes and consequences plus relative importance of microburst precipitation represent outstanding questions in radiation belt physics and may have significant implications ranging from space weather to atmospheric chemistry. Chorus waves are the likely dominant cause of microburst precipitation, but important questions remain regarding the exact nature of the resonance generating the microbursts and the overall importance of the precipitation. These important questions are limited by lack of systematic coordination of simultaneous observations of causative waves in the magnetosphere and resulting precipitating particles at low altitudes. Increased funding for multi-spacecraft missions dedicated to answering these questions is critical.

Sadie Elliott↗
NASA NTRSDate not supplied

CFD Simulations of the IHF 13-Inch Nozzle Flow: 55° Sphere-Cone Model, Manufactured Fences and Gaps

Introduction to Arc-Jets and Testing - Arc-jets are primary facilities to test the performance of thermal protection systems (TPS) in an aerothermodynamic heating environment - Free jet test configuration with stagnation coupon or wedge models—conical nozzles - Semi-free jet test configuration with panel test articles—semi-elliptical nozzles A large-scale sphere-cone model, though similar to stagnation models, enables testing TPS materials in combinations of heat flux, pressure and shear different from those accessible in various stagnation and wedge tests

Arc-jets↗
NASA NTRS2022

An Isolated Mass-gap Black Hole or Neutron Star Detected with Astrometric Microlensing

We present the analysis of five black hole candidates identified from gravitational microlensing surveys. Hubble Space Telescope astrometric data and densely sampled light curves from ground-based microlensing surveys are fit with a single-source, single-lens microlensing model in order to measure the mass and luminosity of each lens and determine if it is a black hole. One of the five targets (OGLE-2011-BLG-0462/MOA-2011-BLG-191 or OB110462 for short) shows a significant >1 mas coherent astrometric shift, little to no lens flux, and has an inferred lens mass of 1.6–4.4 M ⨀ . This makes OB110462 the first definitive discovery of a compact object through astrometric microlensing and it is most likely either a neutron star or a low-mass black hole. This compact-object lens is relatively nearby (0.70–1.92 kpc) and has a slow transverse motion of <30 kms -1 . OB110462 shows significant tension between models well fit to photometry versus astrometry, making it currently difficult to distinguish between a neutron star and a black hole. Additional observations and modeling with more complex system geometries, such as binary sources, are needed to resolve the puzzling nature of this object. For the remaining four candidates, the lens masses are <2M ⨀ , and they are unlikely to be black holes; two of the four are likely white dwarfs or neutron stars. We compare the full sample of five candidates to theoretical expectations on the number of black holes in the Milky Way (∼10 8 ) and find reasonable agreement given the small sample size.

Astrophysical black holes↗
NASA NTRS2024

Bridging the Gap: Enhancing Prominence and Provenance of NASA Datasets in Research Publications

Attribution of datasets that were used to generate research results described in peer-reviewed publications to the original source of these datasets (which are often archived at NASA Earth Science data centers) has been very challenging. Even though the data citation standard of citing datasets as research artifacts and citing them with Digital Object Identifiers (DOIs) was introduced over a decade ago, most authors do not properly reference the data used in their studies and merely mention them in the text. The lack of proper citations of datasets makes the peer-reviewed publication less transparent, imperils reproducibility, and impedes open science. We offer an open-source publication management methodology and a tool that can help to enhance usage-based data discovery, prominence, and provenance of the data; reproducibility of the research results; and potentially increase the return on investment on NASA-funded research.

open-source↗
NASA NTRSDate not supplied

Low-G Slosh Workshop Results From 2023: State of the Art, Gaps and Forward Work

The NASA Engineering and Safety Center (NESC) sponsored a workshop to dis-cuss low-g slosh. Over a dozen different NASA centers and industry partners participated in this workshop. The main topics were to identify the state of the art regarding test data, Computational Fluid Dynamics (CFD) analysis resources, and GN&C models that are available for this problem. The primary intent was to determine deficiencies in the collective knowledge base and to identify priorities that should be established for proactive work in the areas of model development, validation, and model integration. Recommendations from workshop participants include establishing an online slosh modeling resource, conducting ground/flight testing, developing surrogate models, and establishing co-simulation techniques. This paper summarizes the workshop findings and recommendations for the larger community.

Lattice-Boltzmann↗