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Characterization of Optical Energy Output in Thunderstorms to Enhance Severe Thunderstorm Identification
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NASA CA Operations Devolution: Status Update
Get PDFWhat is Devolution? Devolution is a spreading of CA (Conjunction Assessment) operations responsibilities to mission FOTs (Flight Operations Teams): Permits efficiencies in handling the increased workload caused by Space Fence and large constellations; Missions given more flexibility in choosing specific approach to CA requirements that resonates best with their particular needs; CARA (Conjunction Assessment Risk Analysis) retains Agency oversight through an established NASA Standard - will establish requirements for devolved CA preparations, processing, and operations conduct. Devolution is a PROPOSED paradigm under consideration by SMD (Space Missions Directorate): Number of activities required before Agency-level decision can be rendered; Agency requirements established via approved CA Standard; Operational experience testimony from two separate pilot programs; After these activities complete, decision will be made whether devolution is a feasible option for missions; CARA is recommending devolution to exist as an option for missions
First Detection of Lyman-Alpha Scattering Polarization in Off-limb Spicules and Its Constraint on Their Magnetic Field
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CFD Evaluation Of Lean-Direct Injection Combustors for Commercial Supersonics Technology
Get PDFAn overview is given of an effort that focused on using CFD analysis to complement design and configuration definition of Lean-Direct Injection (LDI) combustion concepts for NASA's Commercial Supersonic Transport (CST) program. The National Combustion Code (OpenNCC) was used to perform non-reacting and two-phase reacting flow computations for second and third generation LDI configurations at CST cruise conditions. All computations were performed with a consistent approach of mesh-generation, spray modeling, ignition and kinetics modeling. Emissions (EINOx) characteristics were predicted for CST cruise conditions, and compared with emissions data from experimental measurements to evaluate the fidelity of the CFD modeling approach to predict emissions changes in response to changes in supersonic cycle conditions
Design of a Magnetic Gear for NASA's Vertical Lift Quadrotor Reference Vehicle
Get PDFMagnetic gears are an attractive alternative to mechanical gears for electrified aircraft drive systems due to their ability to transmit torque without mechanical tooth contact. Consequently, magnetic gears enable electrified aircraft to take advantage of the benefits of gearing without introducing most of the contact-related reliability concerns associated with mechanical gearing. Magnetic gears however, have not been shown to match the specific torque (torque/mass) and efficiency of their mechanical counterparts in an aerospace application to date. In this paper, the design of a concentric magnetic gear for a personal air transport NASA reference vehicle is presented to demonstrate the feasibility of a magnetic gear for aerospace applications
Biomass-Burning Smoke Heights over the Amazon Observed from Space
No full textWe characterise the vertical distribution of biomass-burning emissions across the Amazon during the biomass-burning season (JulyNovember) with an extensive climatology of smoke plumes derived from MISR and MODIS (20052012) and CALIOP (20062012) observations. Smoke plume heights exhibit substantial variability, spanning a few hundred metres up to 6 km above the terrain. However, the majority of the smoke is located at altitudes below 2.5 km. About 60 % of smoke plumes are observed in drought years, 40 %50 % at the peak month of the burning season (September) and 94 % over tropical forest and savanna regions, with respect to the total number of smoke plume observations. At the time of the MISR observations (10:0011:00 LT), the highest plumes are detected over grassland fires (with an averaged maximum plume height of 1100 m) and the lowest plumes occur over tropical forest fires (800 m). A similar pattern is found later in the day (14:0015:00 LT) with CALIOP, although at higher altitudes (2300 m grassland vs. 2000 m tropical forest), as CALIOP typically detects smoke at higher altitudes due to its later overpass time, associated with a deeper planetary boundary layer, possibly more energetic fires, and greater sensitivity to thin aerosol layers. On average, 3 %20 % of the fires inject smoke into the free troposphere; this percentage tends to increase toward the end of the burning season (November: 15 %40 %). We find a well-defined seasonal cycle between MISR plume heights, MODIS fire radiative power and atmospheric stability across the main biomes of the Amazon, with higher smoke plumes, more intense fires and reduced atmospheric stability conditions toward the end of the burning season. Lower smoke plume heights are detected during drought (800 m) compared to non-drought (1100 m) conditions, in particular over tropical forest and savanna fires. Drought conditions favour understory fires over tropical forest, which tend to produce smouldering combustion and low smoke injection heights. Droughts also seem to favour deeper boundary layers and the percentage of smoke plumes that reach the free troposphere is lower during these dry conditions. Consistent with previous studies, the MISR mid-visible aerosol optical depth demonstrates that smoke makes a significant contribution to the total aerosol loading over the Amazon, which in combination with lower injection heights in drought periods has important implications for air quality. This work highlights the importance of biome type, fire properties and atmospheric and drought conditions for plume dynamics and smoke loading. In addition, our study demonstrates the value of combining observations of MISR and CALIOP constraints on the vertical distribution of smoke from biomass burning over the Amazon
NASA GeneLab Space Omics Database: Expanding from Space to Ionizing Radiation Data on the Ground
Get PDFNASA GeneLab is an open-access repository for omics datasets generated by biological experiments conducted in space or ground experiments relevant to spaceflight (e.g. simulated cosmic radiation, simulated microgravity, bed rest studies). The GeneLab Data Systems (GLDS) version 4.0 will be available on October 1st 2019, and will provide a state-of-the-art bioinformatics platform for the space biology and radiation communities to upload their data into an omics data commons, to process their data with vetted standard workflows and to compare with existing analyses. Started in 2015 as a repository designed to archive omics data from space experiments, GeneLab has expanded its scope to all ionizing radiation omics experiments conducted on the ground and has put considerable effort in providing carefully characterized radiation metadata on all datasets. GeneLab is also providing processed data derived from the raw data covering a large spectrum of omics (genome, epigenome, transcriptome, epitranscriptome, proteome, metabolome) to help users explore important questions: 1) Which genes or proteins are expressed differently in space for various living organisms? 2) What specific DNA mutations or epigenetic changes happen in space or after exposure to ionizing radiation? and 3) How does genetics affect these responses? Processed data available on GeneLab are derived by standard data analysis workflows vetted by hundreds of scientists who volunteered to join one of the four GeneLab Analysis Working Groups (Animal AWG, Plant AWG, Microbe AWG, Multi-Omics AWG). In this presentation, we will discuss how to bridge the gap between irradiation studies performed on earth and biological experiments conducted in space since the early 1990's. We will discuss how radiation dosimetry was estimated for datasets derived from samples collected during the Space Shuttle era on the International Space Station and on other orbiting platforms. Finally, we will address future strategies regarding dose monitoring in future missions into space, inter-agency efforts to unify data under one umbrella, and knowledge dissemination across the radiation research community and the space biology community
Micromilling of Uniform Nanoparticles for Space Applications
Get PDFFritsch micromills have enhanced one NASA labs ability to develop optimized ceramic nanoparticulate materials for demanding research projects, including energy storage and thermoelectric device applications