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Cryogenic Liquid Level-Sensing using Fiber-Optic Strain Sensor (FOSS) Technology Project

Armstrong innovators have developed a highly accurate method for measuring liquid levels using optical fibers. Unlike liquid level gauges that rely on discrete measurements to give broad approximations of liquid levels, Armstrong&rsquo;s novel method provides measurements at &frac14;-inch intervals within a tank. The system uses fiber optic Bragg sensors located along a single fiber optic cable. These sensors actively discern between the liquid and gas states along a continuous fiber to pinpoint the liquid level. This significant leap forward in precision and accuracy in liquid level sensing offers significant benefits to many industries. Designed to monitor a rocket&rsquo;s cryogenic fuel levels, the technology can be used in many medical and industrial applications.Work to date: The technology has been demonstrated in multiple environments using conventional validation techniques. First, water level measurements have been conducted to demonstrate operation within a benign environment. Second, liquid level measurements were conducted in liquid nitrogen using a 6-foot dewer. Measurements also were conducted within a liquid hydrogen environment using a 4-foot dewer. The technology performed well in all three cases, demonstrating the ability to measure liquid to &frac14; inch.&nbsp;Looking ahead: The team continues to push the fields of application with future tests to determine boundary layers between different fluids such as oil and water. Also there are planned opportunities to demonstrate the technology in a NASA-operated cryogenic test bed, simulating a cryogenic fuel management scenario.Benefits<ul><li>Precise: Can gauge liquid levels within a &frac14;-inch</li><li>Simple: Requires just one fiber optic strand and one metallic wire, as opposed to conventional measurement systems, which require many more wires</li><li>Safe: Is not susceptible to electromagnetic interference (EMI)</li><li>Robust: Can be used in corrosive or toxic liquids without damaging the fiber or contaminating the liquid</li></ul>Applications<ul><li>Aerospace launch vehicles and satellites</li><li>Chemical and refinery plants</li><li>Industrial tanks</li></ul>

AirMSPI terrain-projected georegistered radiance product acquired during the NASA SEAC4RS flight campaign August-September 2013, V005

AirMSPI_SEAC4RS_Terrain-projected_Georegistered_Radiance_Data are AirMSPI terrain-projected georegistered radiance product acquired during the NASA SEAC4RS flight campaign.AirMSPI Level 1B2 products contain radiometric and polarimetric images of clouds, aerosols, and the surface of the Earth. In particular, products contain map-projected data at 8 wavelengths: 355, 380, 445, 470, 555, 660, 865, and 935 nm. The data products include radiance, time, solar zenith, solar azimuth, view zenith, and view azimuth for all spectral bands. Wavelengths for which polarization information is available (470, 660, and 865 nm) also include the Stokes parameters Q and U, as well as degree of linear polarization (DOLP) and angle of linear polarization (AOLP). Q, U, and AOLP are reported relative to both the scattering- and view meridian planes. Files are distributed in HDF-EOS-5 format.This release of AirMSPI data contains all targets acquired during the Studies of Emissions and Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys (SEAC4RS) flight campaign. SEAC4RS was primarily based out of Ellington Field in Houston, Texas (initial flights were based out of Armstrong Flight Research Center in Palmdale, CA), and focused on clouds and aerosols in the United States. AirMSPI data were acquired from August 1 through September 23, 2013.

Propulsive Descent Technologies (PDT): Original Content Project

Future missions to Mars require landed mass that exceeds the capability of current entry, descent, and landing technology.&nbsp; New technology and techniques are required to increase atmospheric entry and landing capabilities for high mass items. This capability is needed in order to enable future human-precursor and human-scale missions to Mars.One possible technology to enable future high mass missions to Mars is the use of retro propulsion during the entry phase.&nbsp; Supersonic retro propulsion involves using thrusters directed in opposition to the oncoming airflow to decelerate the entry vehicle while it is traveling at supersonic speeds.The project will seek to partner with a commercial launch provider to obtain flight data.&nbsp; The data acquired by the proposed government-commercial partnership are expected to include the following aerosciences products:<ul><li>Vehicle state (position, velocity, attitude, attitude rates, etc.)</li><li>Temperatures, heating rates, and pressures on the vehicle&rsquo;s outer skin</li><li>Imagery provided by NASA and its contractors, in addition to vehicle propulsion system performance data.</li></ul>&nbsp;Available NASA Computational Fluid Dynamics (CFD) tools will be exercised at a few select conditions during the SRP burn for each flight data set in order to provide insight into how the models compare against the data.&nbsp; The commercial partner&rsquo;s engines will be properly scaled in the CFD calculations using established scaling parameters with varying degrees of exhaust modeling fidelity.&nbsp; Solutions will be completed on custom grids for each CFD code using geometries provided by the commercial partner.Objectives (for each code):<ol><li>Establish computational requirements (grid, run time, number of CPUs, etc.) and the effects of turbulence modeling and time-accurate simulations on results</li><li>Examine varying levels of engine exhaust modeling (perfect gas vs. simulated gas vs. multi-specie gas)</li><li>Provide best practices for obtaining grid-converged solutions (flow initialization, time step requirements, grid adaptation, etc.)</li><li>Make blind comparisons of the &ldquo;best&rdquo; solutions with the flight data set(s), including flight imagery provided by NASA</li></ol>&nbsp;The PDT project will also develop vehicle configurations that support landing of a 2 metric ton (t) article on the Mars surface.&nbsp; Project representatives will develop trajectories and supersonic retro propulsion profiles for the vehicle configurations using the CFD models.&nbsp; The project will investigate interactions between vehicle subsystems, structures and thermal protection, the Mars aero environment, mass and center of gravity, and control techniques.&nbsp; &nbsp;

AirMSPI verison 6 ellipsoid-projected georegistered radiance product acquired during the ImPACT-PM flight campaign

AirMSPI_ImPACT-PM_Ellipsoid-projected_Georegistered_Radiance_Data is an AirMSPI ellipsoid-projected georegistered radiance product acquired during the JPL and Caltech Imaging Polarimetric Assessment and Characterization of Tropospheric Particulate Matter (ImPACT-PM) flight campaign. AirMSPI Level 1B2 products contain radiometric and polarimetric images of clouds, aerosols, and the surface of the Earth. In particular, products contain map-projected data at 8 wavelengths: 355, 380, 445, 470, 555, 660, 865, and 935 nm. The data products include radiance, time, solar zenith, solar azimuth, view zenith, and view azimuth for all spectral bands. Wavelengths for which polarization information is available (470, 660, and 865 nm) also include the Stokes parameters Q and U, as well as degree of linear polarization (DOLP) and angle of linear polarization (AOLP). Q, U, and AOLP are reported relative to both the scattering and view meridian planes. Files are distributed in HDF-EOS-5 format.This release of AirMSPI data contains all targets acquired during the Imaging Polarimetric Assessment and Characterization of Tropospheric Particulate Matter (ImPACT-PM) flight campaign, which involved the ER-2 based out of Armstrong Flight Research Center in Palmdale, CA and a Navy Twin Otter flying the Caltech CIRPAS suite of instruments based out of Monterey, CA. The campaign was conducted to test a strategy to use multi-angle, spectro-polarimetric remote sensing to retrieve information on the distributions of atmospheric particle types, with emphasis on carbon-containing compounds, as a precursor to NASA’s Multi-Angle Imager for Aerosols, an Earth Venture-Instrument currently in formulation. AirMSPI data were acquired from July 5 through July 8, 2016.

AirMSPI version 6 terrain-projected georegistered radiance product acquired during the CalWater-2 flight campaign Jan-Feb 2015

AirMSPI_CalWater-2_Terrain-projected_Georegistered_Radiance_Data are AirMSPI terrain-projected georegistered radiance product acquired during the Precipitation, Aerosols, and Pacific Atmospheric Rivers Experiment (CalWater-2) flight campaign Jan-Feb 2015. AirMSPI Level 1B2 products contain radiometric and polarimetric images of clouds, aerosols, and the surface of the Earth. In particular, products contain map-projected data at 8 wavelengths: 355, 380, 445, 470, 555, 660, 865, and 935 nm. The data products include radiance, time, solar zenith, solar azimuth, view zenith, and view azimuth for all spectral bands. Wavelengths for which polarization information is available (470, 660, and 865 nm) also include the Stokes parameters Q and U, as well as degree of linear polarization (DOLP) and angle of linear polarization (AOLP). Q, U, and AOLP are reported relative to both the scattering and view meridian planes. Files are distributed in HDF-EOS-5 format.This release of AirMSPI data contains all targets acquired during the Precipitation, Aerosols, and Pacific Atmospheric Rivers Experiment (CalWater-2) flight campaign, which was conducted in partnership between NASA, NOAA, DOE, NSF, Scripps Institution of Oceanography and Colorado State University. The campaign focused on the study of atmospheric rivers and interaction with aerosols offshore of California in the North Pacific. NASA’s ER-2 high-altitude research aircraft, with AirMSPI, was based out of Palmdale, CA. AirMSPI data were acquired from January 20 through February 24, 2015.

Last of the Wild Project, Version 1, 2002 (LWP-1): Global Human Footprint Dataset (IGHP)

The Global Human Footprint Dataset of the Last of the Wild Project, Version 1, 2002 (LWP-1) is the Human Influence Index (HII) normalized by biome and realm. The HII is a global dataset of 1-kilometer grid cells, created from nine global data layers covering human population pressure (population density, population settlements), human land use and infrastructure (built up areas, nighttime lights, land use/land cover), and human access (coastlines, roads, railroads, navigable rivers). The dataset in Interrupted Goode Homolosine Projection (IGHP) is produced by the Wildlife Conservation Society (WCS) and Columbia University Center for International Earth Science Information Network (CIESIN).

UAVSAR Global Hawk POLSAR Project

Integrate the UAVSAR L-band radar to the Global Hawk UAV Bay 25 Provide long range (~ 9000 nmi) to enable data collection of distant areas of interest without complicated deployments Study the ability of the Global Hawk to accommodate UAVSAR &ldquo;Mini-Pods&rdquo; under each wing to enable precision topographic maps and single pass polarimetric interferometry (SPI) providing vertical structure of ice and vegetation.

High Energy Laboratory Astrophysics using an X-Ray Microcalorimeter with an Electron Beam Ion Trap Project

"Since the summer of 2000 we have successfully deployed a high resolution x-ray microcalorimeter spectrometer, based on the spaceflight XRS instrument, at the Electron Beam Ion Trap (EBIT) facility at the Lawrence Livermore National Laboratory. Over the last decade, this highly successful partnership has made fundamental measurements in laboratory astrophysics including the measurements of the absolute cross sections of all the Fe L shell transitions from Fe XVII to Fe XXIV, line ratios in Fe and Ni L shell transitions, measurements of Fe K shell emission over a wide range of electron energies, and direct measurements of charge exchange emission from highly ionized Fe, O, N, and most recently L shell S, using a variety of donor gases. This work has resulted in the publication of over 30 peer-reviewed articles with many more either submitted or in preparation. The newest addition to the facility, the ECS microcalorimeter spectrometer, developed under this program, has performed flawlessly as a facility-class instrument since 2007. We propose here to continue our highly successful partnership and deploy new technology to resolve lines in the important 1/4 keV band that encompasses the M-shell iron emission and the L shell emission, including charge exchange, of many of the lower-Z elements, such as Si, S, Mg, Ne, Ca, and Ar. We thus propose completing a new spectrometer that will bring substantially improved performance to the laboratory astrophysics program at EBIT and will enable fundamentally new measurements. Thus, in addition to maintaining the current spectrometers, which will begin this work, a significant component of this proposal is the completion of a new spectrometer leveraged off of the substantial progress in high-resolution x-ray detectors developed for the International X-ray Observatory mission. The spectrometer will be composed of a detector system with unparalleled spectral resolution: 2 eV resolution across the 0.05-10 keV band. This will allow

Rapid Acquisition Imaging Spectrograph (RAISE) Renewal Proposal Project

The optical design of RAISE is based on a new class of UV/EUV imaging spectrometers that use&nbsp; only two reflections to provide quasi-stigmatic performance simultaneously over multiple wavelengths&nbsp; and spatial fields. Figure 5 summarizes the RAISE instrument design, showing photographs of each of&nbsp; the components or subsystems. The design uses an off-axis parabolic telescope mirror to form a real&nbsp; image of the sun on the spectrometer entrance aperture. A slit then selects a portion of the solar image,&nbsp; passing its light onto a near-normal incidence toroidal grating, which re-images the spectrally dispersed&nbsp; radiation onto two array detectors. Two full spectral passbands over the same one-dimensional spatial&nbsp; field are recorded simultaneously with no scanning of the detectors or grating. The two different spectral&nbsp; bands (1st-order 1205-1243&Aring; and 1526-1564&Aring;) are imaged onto two intensified Active Pixel Sensor&nbsp; (APS) detectors whose focal planes are individually adjusted for optimized performance. The telescope&nbsp; and grating are coated with B4C to enhance short wavelength (2nd order) reflectance (Fig. 6), enabling the&nbsp; instrument to record the brightest lines between 602-622&Aring; and 761-780&Aring; at the same time. Table 1&nbsp; summarizes the main optical parameters for RAISE. &nbsp;&nbsp; TVLS Grating. The single toroidal variable line space (TVLS) grating has a toroidal surface&nbsp; (Sagittal Radius = 640.5 mm, Tangential Radius = 635.3 mm), with varied line space (VLS) rulings of the&nbsp; type developed originally for spherical substrates by Kita, Harada, and collaborators (1983, 1995). By&nbsp; combining this VLS concept with toroidal surfaces, RAISE is the first to exploit this new class of&nbsp; spectrometers, as described by Thomas (2003). For RAISE, the grating is placed 400 mm behind the slit,&nbsp; with focus at a distance of approximately 1700 mm, for a spectrometer magnification of 4.25. By&nbsp; operating at high magnification, the RAISE spectrometer most effectively utilizes the full length and&nbsp; width available in the sounding rocket payload. The first RAISE grating, mechanically ruled by Bach&nbsp; Research, Inc., was delivered in August 2007 and tested for figure, ruling density and total grating&nbsp; efficiency.&nbsp; Intensified APS Cameras. The RAISE Intensified APS camera systems are 1k x 1k CMOS Active&nbsp; Pixel Sensors using miniature digital camera electronics and fed by an MCP intensifier. APS cameras&nbsp; were chosen for RAISE (rather than CCDs) because of their extremely fast readout, direct digital output,&nbsp; low mass, low power, deep full well and high radiation tolerance. The RAISE cameras were developed at&nbsp; DLR (Germany) using a Cypress/Filfactory Star 1000 APS and include a 12-bit external ADC and USB&nbsp; 2.0 interface. We will operate the cameras at 5-10 frames/sec readout, making dark current negligible&nbsp; compared to the incoming signal. The complete camera electronics including its controller is integrated&nbsp; on only one printed circuit board, and uses a rigid-flex 3D-interconnection between the boards to form a&nbsp; lightweight, compact sensor head. Flight detectors were delivered by DLR in August 2008.&nbsp; RAISE Chromospheric Slit Jaw Camera (SJC)&nbsp; To co-align the RAISE spectra with observations from SDO, HINODE, and IRIS, and to collect&nbsp; chromospheric disk images in C IV and the continuum between 1500-1700 &Aring;, the solar image at the&nbsp; telescope focal plane (spectrograph entrance slit plane) is re-imaged onto a SJC mounted on the bo

Fabrication Of Hybird Gas Turbine Disk Material System By Additive Manufacturing Project

AM offers the potential to be revolutionary for GRC hybrid disk concept as it: i) bypasses joining through direct deposition or &ldquo;building&rdquo; of the PX bore alloy on a SX rim and ii) circumvents interface heating issues that may cause microstructural degradation during welding. Our objective is to demonstrate the feasibility of the high payoff AM hydrid disk concept described through test specimens built up using electron beam melting (EBM).

Africa Climate Mobility Initiative (ACMI): Internal Migration Projections

The Africa Climate Mobility Initiative (ACMI) Internal Migration Projections project internal migration flows at 5-year intervals from 2020 to 2050 for a combination of 2 sets of Shared Socioeconomic Pathways (SSPs) scenarios and 3 sets of Representative Concentration Pathways (RCPs) scenarios. The unit of analysis is 7.5 arc-minutes, covering the entire African continent (approximately 15 km at the equator). These grid cells are drawn using a vector representation, and not a tessellation of grid cells (rasters). While the calibration and projection took place at a grid cell resolution of 2.5 arc-minutes, these data have been aggregated to a 7.5 arc-minute resolution. These data underpin the African Shifts Report, produced by the ACMI and enabled by the Global Centre for Climate Mobility (GCCM). The ACMI was launched in September 2021 as a joint initiative of the GCCM, the African Union Commission (AUC), the United Nations System (UN), and the World Bank.

Global 1-km Downscaled Urban Land Extent Projection and Base Year Grids by SSP Scenarios, 2000-2100

The Global 1-km Downscaled Urban Land Extent Projection and Base Year Grids by SSP Scenarios, 2000-2100 consists of global SSP-consistent spatial urban land fraction data for the base year 2000 and projections at ten-year intervals for 2010-2100 at a resolution of 1-km (about 30 arc-seconds). An algorithm was developed and validated to downscale the 1/8-degree resolution data set to 1-km resolution. For a given decade, the downscaling algorithm allocates the 1/8-degree decadal amount of urban land expansion to 1-km grid cells in proportion to their total urban land amounts at the beginning of the decade. The algorithm uses an iterative process to collect any overflows from already highly-developed 1-km grid cells, and then allocates them to 1-km grid cells that are not yet fully developed. This iterative process repeats itself until all 1/8-degree amounts of urban land expansion are allocated to 1-km grid cells with no overflow. The downscaling process is applied decade by decade throughout the 21st century for each urban land expansion scenario. The final product is a set of global maps displaying the 1-km fraction of urban land, updated at decadal intervals throughout the 21st century, for five different urban land expansion scenarios consistent with the Shared Socioeconomic Pathways (SSPs).

Magnetically-coupled microcalorimeter arrays for x-ray astrophysics with sub-eV spectral resolution and large format capability Project

"We propose to develop a revolutionary x-ray camera for astrophysical imaging spectroscopy. High-resolution x-ray spectroscopy is a powerful tool for studying the evolving universe. Emission line ratios (e.g. within the He-like triplet) provide density and temperature diagnostics. Emission and absorption line energies identify ions and determine their velocities, and the shape of the lines can be used to study turbulence or the relativistic effects of a supermassive black hole. The grating spectrometers on the XMM and Chandra satellites demonstrated the power of high-resolution x-ray spectroscopy for astrophysics, but there remains a need for instrumentation that can provide higher spectral resolution with high throughput in the Fe-K band and that can enable spatial/spectral investigations of extended sources, such as supernova remnants and galaxy clusters. The instrumentation needed is a broad-band imaging spectrometer - basically an x-ray camera that can precisely resolve x-ray energies and fluxes over a large field-of-view. While we do not claim that in 3 years we will have developed such detectors, we advocate developing the technology that has the greatest potential for achieving this. Theoretically, magnetically-coupled microcalorimeters are best equipped to achieve sub-eV energy resolution in very large formats. We propose to build upon the work carried out by our group on metallic magnetic calorimeters (MMC) in the antecedent program. The great promise of MMCs for sub-eV energy resolution has been recognized for years. During our current research program, an accident in detector fabrication produced devices that derived their sensitivity from a different operating principle - the temperature dependence of a superconduc

GREECE -- Ground-to-Rocket Electrodynamics-Electrons Correlative Experiment: High resolution rocket and ground-based investigations of small-scale auroral structure and dynamics Project

Methodology The methodology is based on making comparisons between downward electron flux, DC electric fields, electromagnetic waves, and auroral morphology. The proposed project will launch a rocket from Poker Flat over Fort Yukon to an apogee of 200-300 km when arc or arcs are present that has optical shear-flows present. Data from downgoing electron fluxes over a large energy range, electron density (Langmuir probe), electric and magnetic fields from the in-situ rocket payload and images from all-sky and narrow field cameras at Poker Flat and Fort Yukon will be produced and analyzed. All instrumentation is selected so that high temporal resolution can be achieved. &nbsp;

US Participation in the Solar Orbiter Multi Element Telescope for Imaging and Spectroscopy (METIS) Project

The Multi Element Telescope for Imaging and Spectroscopy, METIS, investigation has been conceived to perform off-limb and near-Sun coronagraphy and is motivated by the aim of addressing the three key scientific questions identified as the focus of the HELEX program. These questions concern: the origin and heating/acceleration of the solar wind streams; the origin, acceleration and transport of the solar energetic particles; and the transient ejection of coronal mass and its evolution in the inner heliosphere (coronal mass ejections, CME&rsquo;s). The investigation aims to provide crucial tests apt to verify the hypotheses and models on the following main issues of solar coronal physics that have been developed primarily during the SOHO era: &bull; Is the slow solar wind originating according to more than one physical process and which is the level of contribution of the possible different sources of slow wind to the heliospheric wind observed &lsquo;in situ&rsquo;? &bull; How does the magnetic field topology control the outflow velocity and composition of the slow and fast solar wind? &bull; Is the magnetic field controlling the emergence of the fast wind at the base of coronal holes? &bull; Do polar plumes and inter-plume regions have a role in channeling the fast wind? &bull; Is ion cyclotron dissipation of fast Alfv&eacute;n waves the primary energy deposition process in the fast wind? &bull; Is the reconnection at the base of coronal holes responsible for the generation of waves and turbulence that energize the fast wind? &bull; Which is the nature of coronal heating in open and closed field regions? &bull; Which is the source of the seed particles of the Solar Energetic Particles (SEPs)? &bull; Which is the role of coronal shocks driven by coronal mass ejections in energizing SEPs? &bull; Which are the mass and magnetic fluxes carried out from the Sun during transient events? &bull; How does the evolution of the coronal magnetic field, inferred from the large-scale evolution of the outer corona, trigger coronal mass ejections? &bull; How does the corona re-adjust after coronal mass ejections on medium-term time scales, ranging between 3 and 10 days (not yet established in the outer corona)? &bull; How do the quiescent streamers evolve on time scales ranging between 3 and 10 days? The crucial tests for addressing and solving these still open issues can be achieved by combining the instrument&rsquo;s versatility with the uniqueness of the Solar Orbiter mission profile, which allows: a close approach to the Sun thus leading to a significant improvement in spatial resolution; quasi co-rotation with the Sun, which allows to nearly freeze for several days both the on-disk inner corona and the outer corona in the plane of the sky and, thus, disentangle the evolution of coronal structures and solar rotational effects on medium-term time scales, an outof- ecliptic view of the Sun. METIS instrument is designed to combine and extend the imaging and spectroscopic capabilities of the SOHO and STEREO coronagraphs and spectrometers in order to exploit at &nbsp;

Poverty Mapping Project: Poverty and Food Security Case Studies

The Poverty Mapping Project: Poverty and Food Security Case Studies data set consists of small area estimates of poverty, inequality, food security and related measures for subnational administrative Units in Mexico, Ecuador, Kenya, Malawi, Bangladesh, Sri Lanka, Nigeria and Vietnam. These data come from country level cases studies that examine poverty and food security from a spatial analysis perspective. The data products include shapefiles (vector data) and tabular data sets (csv format). Additionally, a data catalog (xls format) containing detailed information and documentation is provided. This data set is produced by the Columbia University Center for International Earth Science Information Network (CIESIN) and Centro Internacional de Agricultura Tropical (CIAT). The data set was originally produced by CIAT, International Maize and Wheat Improvement Center (CIMMYT), International Livestock Research Institute (ILRI), International Food Policy Research Institute (IFPRI), International Rice Research Institute (IRRI), International Water Management Institute (IWMI), and International Institute for Tropical Agriculture (IITA).

Last of the Wild Project, Version 3 (LWP-3): 2009 Human Footprint, 2018 Release

The 2009 Human Footprint, 2018 Release provides a global map of the cumulative human pressure on the environment in 2009, at a spatial resolution of ~1 km. The human pressure is measured using eight variables including built-up environments, population density, electric power infrastructure, crop lands, pasture lands, roads, railways, and navigable waterways. The data set is produced by Venter et.al., and is available in the Mollweide projection.

Country-Level GDP and Downscaled Projections Based on the SRES A1, A2, B1, and B2 Marker Scenarios, 1990-2100

The Country-Level GDP and Downscaled Projections Based on the Special Report on Emissions Scenarios (SRES) A1, A2, B1, and B2 marker scenarios, 1990-2100, were developed using the 1990 base year GDP (Gross Domestic Product) from national accounts database available from the UN Statistics Division. SRES regional GDP growth rates were calculated from 1990 to 2100 based on the SRES marker model regional data and applied uniformly to each country that fell within the SRES-defined regions. This data set is produced and distributed by the Columbia University Center for International Earth Science Information Network (CIESIN).

Silicon Micromachined Heterodyne Array Receiver at 1.9 THz Project

"We are proposing a new concept of integrated component development technology at submillimeter wavelengths that will dramatically simplify the fabrication, assembly, and integration of large focal plane arrays and imagers. This technology has the potential to significantly increase the pixel count of detector arrays and reduce the mass, volume, and complexity of array receivers for a broad range of applications in astrophysics and earth sciences. We will develop and demonstrate a highly integrated silicon-micromachined array receiver at 1.9 THz based on advanced dual-polarized, sideband-separating, balanced heterodyne mixers. The receiver front-end will be integrated with a novel micro-lens antenna array. We will design full-waveguide-band 90-degree quadrature hybrids, orthomode transducers (OMT), polarization twists, in-phase power splitters, and directional couplers at 1.9 THz; fabricate them using deep reactive ion etching (DRIE) based silicon micromachining, integrate them with existing HEB mixers at 1.9 THz; and test and fully characterize them in our laboratory. The scientific importance of high-resolution spectroscopic observations at submillimeter wavelengths is underscored by the key role of heterodyne spectrometers in the ESA cornerstone Herschel Space Observatory as well as the ground-based ALMA and airborne SOFIA. Star formation and key phases of galaxy evolution occur in region enshrouded by dust that obscures them at infrared and optical wavelengths, while the temperature range of the interstellar medium of ten to a few thousand Kelvin in these regions excites a wealth of submillimeter-wave spectral lines. With high-resolution spectroscopy, resolved line profiles reveal the dynamics of star formation, directly revealing details of turbulence, outflows, and core collapse. Observations of emission from ionized species such as C+ at 1900.53690 GHz (158 um), allow one to directly measure the cooling of the diffuse component of the interstellar m

High Thrust-Density Electrostaic Engines Project

These issues are addressable by: increasing the thrust, power, and thrust-to-power ratio capability of EP systems; reducing the non-recurring engineering systems costs; and developing system architectures with performance characteristics that capture the broadest possible range of missions so that development &amp; flight costs are amortized over multiple users.&nbsp; We believe these objectives can be achieved by developing the Next Generation Electric Propulsion Thruster (NGEPT); a GRC-patented modular EP device based on a new arrangement of relatively mature and proven technologies with the potential to yield revolutionary capabilities