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NASA NTRS2009

Rare Earth Element Measurements of Melilite and Fassaite in Allende Cai by Nanosims

The rare earth elements (REEs) are concentrated in CAIs by approx. 20 times the chondritic average [e.g., 1]. The REEs in CAIs are important to understand processes of CAI formation including the role of volatilization, condensation, and fractional crystallization [1,2]. REE measurements are a well established application of ion microprobes [e.g., 3]. However the spatial resolution of REE measurements by ion microprobe (approx.20 m) is not adequate to resolve heterogeneous distributions of REEs among/within minerals. We have developed methods for measuring REE with the NanoSIMS 50L at smaller spatial scales. Here we present our initial measurements of REEs in melilite and fassaite in an Allende Type-A CAI with the JSC NanoSIMS 50L. We found that the key parameters for accurate REE abundance measurements differ between the NanoSIMS and conventional SIMS, in particular the oxide-to-element ratios, the relative sensitivity factors, the energy distributions, and requisite energy offset. Our REE abundance measurements of the 100 ppm REE diopside glass standards yielded good reproducibility and accuracy, 0.5-2.5 % and 5-25 %, respectively. We determined abundances and spatial distributions of REEs in core and rim within single crystals of fassaite, and adjacent melilite with 5-10 m spatial resolution. The REE abundances in fassaite core and rim are 20-100 times CI abundance but show a large negative Eu anomaly, exhibiting a well-defined Group III pattern. This is consistent with previous work [4]. On the other hand, adjacent melilite shows modified Group II pattern with no strong depletions of Eu and Yb, and no Tm positive anomaly. REE abundances (2-10 x CI) were lower than that of fassaite. These patterns suggest that fassaite crystallized first followed by a crystallization of melilite from the residual melt. In future work, we will carry out a correlated study of O and Mg isotopes and REEs of the CAI in order to better understand the nature and timescales of its formation process and subsequent metamorphic history.

Ito, M.↗
NASA NTRS2006

Using Flow Regime Lightning and Sounding Climatologies to Initialize Gridded Lightning Threat Forecasts for East Central Florida

Each morning, the forecasters at the National Weather Service in Melbourne, FL (NWS MLB) produce an experimental cloud-to-ground (CG) lightning threat index map for their county warning area (CWA) that is posted to their web site (http://www.srh.weather.gov/mlb/ghwo/lightning.shtml) . Given the hazardous nature of lightning in East Central Florida, especially during the warm season months of May September, these maps help users factor the threat of lightning, relative to their location, into their daily plans. The maps are color-coded in five levels from Very Low to Extreme, with threat level definitions based on the probability of lightning occurrence and the expected amount of CG activity. On a day in which thunderstorms are expected, there are typically two or more threat levels depicted spatially across the CWA. The locations of relative lightning threat maxima and minima often depend on the position and orientation of the low-level ridge axis, forecast propagation and interaction of sea/lake/outflow boundaries, expected evolution of moisture and stability fields, and other factors that can influence the spatial distribution of thunderstorms over the CWA. The lightning threat index maps are issued for the 24-hour period beginning at 1200 UTC each day with a grid resolution of 5 km x 5 km. Product preparation is performed on the AWIPS Graphical Forecast Editor (GFE), which is the standard NWS platform for graphical editing. Currently, the forecasters create each map manually, starting with a blank map. To improve efficiency of the forecast process, NWS MLB requested that the Applied Meteorology Unit (AMU) create gridded warm season lightning climatologies that could be used as first-guess inputs to initialize lightning threat index maps. The gridded values requested included CG strike densities and frequency of occurrence stratified by synoptic-scale flow regime. The intent is to improve consistency between forecasters while allowing them to focus on the mesoscale detail of the forecast, ultimately benefiting the end-users of the product. Several studies took place at the Florida State University (FSU) and NWS Tallahassee (TAE) in which they created daily flow regimes using Florida 1200 UTC synoptic soundings and CG strike densities, or number of strikes per specified area. The soundings used to determine the flow regimes were taken at Miami (MIA), Tampa (TBW), and Jacksonville (JAX), FL, and the lightning data for the strike densities came from the National Lightning Detection Network (NLDN). The densities were created on a 2.5 km x 2.5 km grid for every hour of every day during the warm seasons in the years 1989-2004. The grids encompass an area that includes the entire state of Florida and adjacent Atlantic and Gulf of Mexico waters. Personnel at FSU and NWS TAE provided this data and supporting software for the work performed by the AMU.

Lambert, Winifred↗
NASA NTRS2007

Using Flow Regime Lightning and Sounding Climatologies to Initialize Gridded Lightning Threat Forecasts for East Central Florida

Each morning, the forecasters at the National Weather Service in Melbourne, FL (NWS MLB) produce an experimental cloud-to-ground (CG) lightning threat index map for their county warning area (CWA) that is posted to their web site (httl://www.srh.weather.gov/mlb/ghwo/lightning.shtml) . Given the hazardous nature of lightning in East Central Florida, especially during the warm season months of May September, these maps help users factor the threat of lightning, relative to their location, into their daily plans. The maps are color-coded in five levels from Very Low to Extreme, with threat level definitions based on the probability of lightning occurrence and the expected amount of CG activity. On a day in which thunderstorms are expected, there are typically two or more threat levels depicted spatially across the CWA. The locations of relative lightning threat maxima and minima often depend on the position and orientation of the low-level ridge axis, forecast propagation and interaction of sea/lake/outflow boundaries, expected evolution of moisture and stability fields, and other factors that can influence the spatial distribution of thunderstorms over the CWA. The lightning threat index maps are issued for the 24-hour period beginning at 1200 UTC each day with a grid resolution of 5 km x 5 km. Product preparation is performed on the AWIPS Graphical Forecast Editor (GFE), which is the standard NWS platform for graphical editing. Until recently, the forecasters created each map manually, starting with a blank map. To improve efficiency of the forecast process, NWS MLB requested that the Applied Meteorology Unit (AMU) create gridded warm season lightning climatologies that could be used as first-guess inputs to initialize lightning threat index maps. The gridded values requested included CG strike densities and frequency of occurrence stratified by synoptic-scale flow regime. The intent was to improve consistency between forecasters while allowing them to focus on the mesoscale detail of the forecast. Several studies took place at the Florida State University (FSU) and NWS Tallahassee (TAE) in which they created daily flow regimes using Florida 1200 UTC synoptic soundings and CG strike densities, or number of strikes per specified area. The soundings used to determine the flow regimes were taken at Miami (MIA), Tampa (TBW), and Jacksonville (JAX), FL, and the lightning data for the strike densities came from the National Lightning Detection Network (NLDN). The densities were created on a 2.5 km x 2.5 km grid for every hour of every day during the warm seasons in the years 1989-2004. The grids encompass an area that includes the entire state of Florida and adjacent Atlantic and Gulf of Mexico waters. Personnel at FSU and NWS TAE provided this data and supporting software for the work performed by the AMU.

Lambert, Winifred↗
NASA NTRSDate not supplied

Climate Information and Lessons Learned from the NASA Earth eXchange (NEX), Short-term Prediction Research and Transition Center (NASA SPoRT), and the NASA Regional Climate Model Evaluation System (RCMES)

Climate resilience can emerge from a combination of (1) climate projections that enable future-oriented planning and (2) contemporary observations that can be used for adaptation in the face of realized climate. NASA is uniquely positioned to provide global climate projections and satellite-based observations to users who must take a global perspective on climate risk (e.g., supply chain managers). Here, we will share the capabilities and experiences of three NASA projects. The first project, the NASA Earth eXchange (NEX) provides two downscaled climate projections, NEX-GDDP-CMIP6, a global 25 km resolution product, and NEX-DCP30-CMIP6, an 800 m resolution product covering the coterminous U.S. specifically designed for U.S. National Climate Assessment (NCA). NEX also offers land surface products that mirror the twice-daily products provided by the Moderate Resolution Imaging Spectroradiometer (MODIS) but are derived from operational geostationary weather satellite data collected at 5-10 minutes intervals. The second project, the Short-term Prediction Research and Transition Center (SPoRT), was established in 2002 to transition unique NASA satellite products and capabilities to stakeholders to improve decision-making that benefits society. SPoRT provides products and capabilities derived from NASA observations and models to end users in government, academia, and the private sector. SPoRT translates NASA Earth science into actionable solutions reaching over 400 stakeholders across 80 organizations. Finally, the Regional Climate Model Evaluation System (RCMES) is designed to facilitate regional-scale evaluations of climate models by providing standardized access to a vast and comprehensive set of observations, such as satellite, in-situ, and reanalyses, and modeling resources such as CMIP & CORDEX. These three projects form part of the core capabilities at the NASA Centers deliver climate information under the new NASA Earth Science to Action (ES2A) strategy.

NEX↗
NASA NTRS1999

An Analysis of Gravity-Field Estimation Based on Intersatellite Dual-1-Way Biased Ranging

The GRACE (Gravity Recovery And Climate Experiment) mission is designed to make global, highly accurate measurements of the Earth's gravity field with high spatial resolution. Ancillary GPS occultation measurements are also to be carried out for atmospheric monitoring. In the dual-1-way biased ranging of this mission, the range between two satellites separated by 100 to 200 km in nearly polar, coplanar, circular orbits, is measured to very high precision, to within an additive constant, through the exchange of K- and Ka-band sinusoidal signals. Such biased ranging data, along with GPS L-band range and phase data, can be processed and fit over successive multiday intervals to obtain accurate estimates of the Earth's gravity field. This report approximately models and analyzes this process, from the generation of the RF signals at the two satellites through the extraction of the geopotential. The steps include generation of the transmitted signals, processing the received signals to extract high-rate baseband phase, carrying out a dual-1-way combination of baseband phase to extract high-rate biased range for each band, combining K- and Ka-band ranges to correct for the ionosphere effect, and processing the resulting high-rate biased range values to extract three types of reduced-rate observables: biased range, range rate and range acceleration. The version of dual-1-way biased ranging developed by this report improves upon previous versions in a number of ways: highly accurate satellite-timetag corrections derived from concurrent GPS data, better baseband phase extraction using highly digital processing, highly accurate USO-rate calibration derived from concurrent GPS data, an improved method for extracting high-rate biased range from baseband phase, improved filtering for extracting reduced- rate observables from high-rate biased range, and parallel extraction of three observable types.

SINUSOIDAL SIGNALS↗
NASA NTRS1976

One-millimeter continuum emission studies of four molecular clouds

Maps with 1-arcmin resolution are presented of 1-mm thermal emission from dust grains in the central portions of the molecular clouds associated with four H II regions: W3, M42 (OMC-1), Sgr B2, and W49. The maps cover regions approximately 5 by 5 arcmin in extent. In each source, a sharp peak in the 1-mm surface brightness is seen at the position of a compact H II region and/or one or several luminous near-infrared sources. The radial density distributions in the center of the clouds have been estimated from the observed distribution of 1-mm surface brightness near the peaks. The results indicate that the central density gradients are quite steep. These gradients may have been established in the clouds by the collapse processes which led to the formation of the central luminous objects.

Westbrook, W. E.↗
NASA NTRS1980

A solar activity monitoring platform for SCADM

The adaptation of proven space probe technology is proposed as a means of providing a solar activity monitoring platform which could be injected behind the Earth's orbital position to give 3 to 6 days advanced coverage of the solar phenomenon on the backside hemisphere before it rotates into view and affects terrestrial activities. The probe would provide some three dimensional discrimination within the ecliptic latitude. This relatively simple off-Earth probe could provide very high quality data to support the SCADM program, by transmitting both high resolution video data of the solar surface and such measurements of solar activity as particle, X-ray, ultraviolet, and radio emission fluxes. Topics covered include the orbit; constraints on the spacecraft; subsystems and their embodiments; optical imaging sensors and their operation; and the radiation-pressure attitude control system are described. The platform would be capable of mapping active regions on an hourly basis with one arc-second resolution.

Kissell, K. E.↗
NASA NTRS1993

High-resolution radio observations of the supernova remnant 3C 391 - Possible breakout morphology

We present radio observations of the bright compact SNR 3C 391 (G31.9+0.0) made with the VLA2 at 6 arcsec resolution. The remnant's morphology suggests expansion into a medium with a very strong density gradient. We interpret radio and X-ray morphologies as evidence for a breakout of the expanding material into a region of abruptly lower density. The CO survey of Sanders et al. (1986), though not fully sampled, shows the presence of molecular gas at the position of the remnant, with a radial velocity of 90-110 km/s similar to the highest velocity absorption features seen in H I toward 3C 391. This gas may thus be near the remnant, though direct evidence of interaction is lacking. More detailed CO observations, and searches for evidence of shocked molecular gas such as 2.12 micron emission from H2, might confirm or refute the tantalizing possibility that 3C 391 is interacting with an observable molecular cloud.

Reynolds, Stephen P.↗
NASA NTRS1994

A kinematic search for supernova remnants in giant extragalactic H II regions

We have obtained velocity fields of the Giant H II complexes NGC 5471 in M101, NGC 2363 in NGC 2366, and the largest H II region in NGC 2403 from H-alpha observations using the TAURUS imaging Fabry-Perot interferometer. We have detected five H-alpha sources with velocity profiles which are broad when compared with the surrounding H II region. Region B in NGC 5471 has been previously determined to contain a supernova remnant by the presence of nonthermal radio continuum radiation and enhanced (O I) and (S II) emission (Skillman 1985) and broad H-alpha emission (Chu & Kennicutt 1986). Two broad H-alpha sources in NGC 2363 coincide with regions where strong splitting has been found in the (O III) line (Roy et al. 1991). Two more broad H-alpha sources have been identified in the largest H II region in NGC 2403. Very Large Array (VLA) radio continuum observations with a resolution of 2 sec at lambda(6) and lambda(20) cm of all 3 H II complexes are presented. In addition, high resolution (subarcsecond) VLA images of NGC 5471 were made at lambda(2) and lambda(6) cm. The presence of a nonthermal source in region NGC 5471 B was confirmed while region NGC 5471 A appears to be dominated by thermal emission. The nonthermal spectral index in NGC 2363 A indicates the existence of none or more supernova remnants at the position of a large velocity width source detected in H-alpha emission. No similar nonthermal sources were detected in NGC 2403 #1. Supernovae explosions and stellar winds are considered as causes for these large velocity width sources (LVWS). If the emission from the LVWSs is attributed to single supernova remnants, they are unusually luminous in both nonthermal radio continuum and H-alpha emision. The very large H-alpha luminosities could be a result of high velocity gas being ionized by the neighboring stellar cluster.

Yang, Hui↗
NASA NTRS1996

An Ultraviolet-Excess Optical Candidate for the Luminous Globular Cluster X-Ray Source in NGC 1851

The intense, bursting X-ray source in the globular cluster NGC 1851 was one of the first cluster sources discovered, but has remained optically unidentified for 25 years. We report here on results from Hubble Space Telescope WFPC2 multicolor images in NGC 1851. Our high spatial resolution images resolve approximately 200 objects in the 3 minute radius Einstein X-ray error circle, 40 times as many as in previous ground-based work. A color-magnitude diagram of the cluster clearly reveals a markedly UV-excess object with B approximately 21, (U - B) approximately -0.9, only 2 minutes from the X-ray position. The UV-excess candidate is 0.12 minutes distant from a second, unremarkable star that is 0.5 mag brighter in B; thus ground-based studies of this field are probably impractical. Three other UV-excess objects are also present among the approximately 16,000 objects in the surveyed region of the cluster, leaving an approximately 5% probability that a UV-excess object has fallen in the X-ray error circle by chance. No variability of the candidate is seen in these data, although a more complete study is required. If this object is in fact the counterpart of the X-ray source, previous inferences that some globular cluster X-ray sources are optically subluminous with respect to low-mass X-ray binaries in the field are now strengthened.

Deutsch, Eric W.↗
NASA NTRS2002

Spatiotemporal Variability and Propagation of Equatorial Noise Observed by Cluster

We report a multipoint case study of the electromagnetic equatorial noise observed by the Cluster project. High-resolution data were measured in three close points in space located in the morning sector of the outer plasmasphere. We demonstrate a narrow latitudinal extent of the emissions with a typical width of 2 degrees, centered near the minimum-B equator. Power spectra recorded by the different satellites show a complex structure of emission lines whose relative intensities and positions vary at timescales of 1-2 min and/or at spatial scales of tens of wavelengths. These lines do not match harmonics of the local proton cyclotron frequency, as it would be expected if the waves are generated by energetic ions and observed near the source region. We bring observational evidence that the waves propagate with a significant radial component and thus can propagate from a distant generation region located at different radial distances where ion cyclotron frequencies match the observed fine structure.

Santolik, O.↗
NASA NTRS2020

Simple, Compact, High-Resolution Monochromatic X-Ray Source for Characterization of X-Ray Calorimeter Arrays

X-ray calorimeters routinely achieve very high spectral resolution, typically a few eV full width at half maximum (FWHM). Measurements of calorimeter line shapes are usually dominated by the natural linewidth of most laboratory calibration sources. This compounds the data acquisition time necessary to statistically sample the instrumental line broadening and can add systematic uncertainty if the intrinsic line shape of the source is not well known. To address these issues, we have built a simple, compact monochromatic x-ray source using channel cut crystals. A commercial x-ray tube illuminates a pair of channel cut crystals that are aligned in a dispersive configuration to select the Kα1 line of the x-ray tube anode material. The entire device, including the x-ray tube, can be easily hand-carried by one person and may be positioned manually or using a mechanical translation stage. The output monochromatic beam provides a collimated image of the anode spot with magnification of unity in the dispersion direction (typically 100 μm–200 μm for the x-ray tubes used here) and is unfocused in the cross-dispersion direction so that the source image in the detector plane appears as a line. We measured output count rates as high as 10 count/s/pixel for the Hitomi soft x-ray spectrometer, which had 819 μm square pixels. We implemented different monochromator designs for energies of 5.4 keV (one design) and 8.0 keV (two designs), which have effective theoretical FWHM energy resolution of 0.125 eV, 0.197 eV, and 0.086 eV, respectively; these are well-suited for optimal calibration measurements of state-of-the art x-ray calorimeters. We measured an upper limit for the energy resolution of our Cr Kα1 monochromator of 0.7 eV FWHM at 5.4 keV, consistent with the theoretical prediction of 0.125 eV.

M A Leutenegger↗
NASA NTRS1988

Compact radio cores in three Seyfert galaxies - High resolution studies of Mkn 3, Mkn 231, and Mkn 463

The small-scale morphologies of Mkn 231 and Mkn 463 have been investigated using the European VLBI Network (EVN) at 1.6 GHz and the VLA at 15 and 22 GHz. Mkn 3 has been studied using the EVN at 1.4 and 1.6 GHz. All of the galaxies have a substantial fraction of their core radio flux in linear or elongated structures, typically tens of parsecs in extent. Agreement between the parsec- and kiloparsec-scale position angles of continuum radio emission suggests collimated outflow from the galaxy centers that continues over several orders of magnitude in scale. Supernova rates of order one hundred per year on scales of tens of parsecs are required to explain the nuclear radio emission as the result of bursts of star formation. The luminosities, small extents, and linear morphologies of the radio sources all support the idea that the nuclear radio sources are energized by active galactic nuclei and therefore support the more general picture of Seyfert galaxy nuclei being low-luminosity quasars. All of the galaxies appear to have undergone violent interactions in the recent past.

Neff, S. G.↗
NASA NTRS1973

Overall evaluation of ERTS-1 imagery for cartographic application

The author has identified the following significant results. Significant scientific conclusions are: (1) Bulk RBV's have internal positional accuracy in the order of 70 meters at ground scale while MSS internal accuracy is in the order of 200 to 300 meters. Both have precision processed images with accuracy within 70 meters. (2) Image quality exhibited by detectability and acutance is better than expected and perhaps twice as good as would be achieved by photographic film of the same resolution. (3) Photometric anomalies (shading) have limited RBV multispectral application, but it is believed that these anomalies can be further reduced. (4) The MSS has exceptionally high photometric fidelity but the matching of scenes taken under different conditions of illumination has not been resolved. (5) MSS bands 6 and 7 have enormous potential for surface water mapping including the correlation of shorelines at various water stages. (6) MSS band 7 demonstrates an actual cloud penetration capability beyond what was expected. It also has delineated cultural features better than the other MSS bands under certain conditions.

Colvocoresses, A. P.↗
NASA NTRS1979

Observations of far-infrared fine structure lines - Forbidden O III 88.35 microns and forbidden O I 63.2 microns

Results are presented for observations of the fine-structure lines of forbidden O III at 88.35 microns and forbidden O I at 63.2 microns in a number of sources by means of an airborne far-IR spectrometer. The sources M17, NGC 7538, and W51 are mapped in the forbidden O III line with a resolution of 1 arcmin, and the emission peak is found to coincide with the maximum radio continuum in all cases. The far-IR continuum is simultaneously mapped where possible; the continuum peak is shown to be distinct from the center of ionization in the same three sources. The forbidden O III line is also detected in W3, W49, and several positions in M42 (Orion). The forbidden O I line is detected in M17, in M42, and marginally in DR 21. An unsuccessful search for the J = 1-0 transition of HD at 112 microns in the direction of the Kleinmann-Low nebula is also reported.

Storey, J. W. V.↗
NASA NTRS1991

Infrared spectroscopy of cometary parent molecules

The wealth of information on cometary physics provided by high-resolution spectroscopy of the IR water transitions is discussed. Specifically, the absolute line intensities and spatial brightness profiles are used to determine water production rates and lifetimes; the relative line intensities and spatial brightness profiles are used to determine water production rates and lifetimes; the relative line intensities probe the kinetic temperature profile in the coma; the line widths and line positions shed light on the coma outflow dynamics; and the temporal variability in the lines provides information on the structure of the nucleus. These observations also make it possible to determine the water ortho-to-para ratio, which may elucidate the origin and/or evolution of cometary nuclei. Recent advances in IR instrumentation promise to extend sensitivities for parent molecule searches to relative abundances well below 1 percent, especially if cooled, earth-orbiting facilities are available.

Weaver, H. A.↗
NASA NTRS1998

Atmos/Atlas 3 Infrared Profile Measurements of Trace Gases in The November 1994 Tropical and Subtropical Upper Troposphere

Vertical mixing ratio profiles of four relatively long-lives gases, HCN, C2H2, CO, and C2H6, have been retrieved from 0.01/cm resolution infrared solar occultation spectra recorded between latitudes of 5.3degN and 31.4degN. The observations were obtained by the Atmospheric Trace Molecule Spectroscopy (ATMOS) Fourier transform spectrometer during the Atmospheric Laboratory for Applications and Science (ATLAS) 3 shuttle flight, 3-12 November 1994. Elevated mixing ratios below the tropopause were measured for these gases during several of the occultations. The positive correlations obtained between the simultaneously measured mixing ratios suggest that the enhancements are likely the result of surface emissions, most likely biomass burning and/or urban industrial activities, followed by common injection via deep convective transport of the gases to the upper troposphere. The elevated levels of HCN may account for at least part of the "missing NO," in the upper troposphere. Comparisons of the observations with values measured during a recent aircraft campaign are presented.

Rinsland, C. P.↗
NASA NTRS2001

A Space Based Internet Protocol System for Sub-Orbital Tracking and Control

Personnel from the Goddard Space Flight Center Wallops Flight Facility (GSFC/WFF) in Virginia are responsible for the overall management of the NASA Sounding Rocket Program. Payloads are generally in support of NASA's Space Science Enterprise's missions and return a variety of scientific data as well as providing a reasonably economical means of conducting engineering tests for instruments and devices used on satellites and other spacecraft. The fifteen types of sounding rockets used by NASA can carry payloads of various weights to altitudes from 50 km to more than 1,300 km. Launch activities are conducted not only from established missile ranges, but also from remote locations worldwide requiring mobile tracking and command equipment to be transported and set up at considerable expense. The advent of low earth orbit (LEO) commercial communications satellites provides an opportunity to dramatically reduce tracking and control costs of launch vehicles and Unpiloted Aerial Vehicles (UAVs) by reducing or eliminating this ground infrastructure. Additionally, since data transmission is by packetized Internet Protocol (IP), data can be received and commands initiated from practically any location. A low cost Commercial Off The Shelf (COTS) system is currently under development for sounding rockets which also has application to UAVs and scientific balloons. Due to relatively low data rate (9600 baud) currently available, the system will first be used to provide GPS data for tracking and vehicle recovery. Range safety requirements for launch vehicles usually stipulate at least two independent tracking sources. Most sounding rockets flown by NASA now carry GPS receivers that output position data via the payload telemetry system to the ground station. The Flight Modem can be configured as a completely separate link thereby eliminating requirement for tracking radar. The system architecture which integrates antennas, GPS receiver, commercial satellite packet data modem, and a single board computer with custom software is described along with the technical challenges and the plan for their resolution. These include antenna development, high Doppler rates, reliability, environmental ruggedness, hand over between satellites and data security. An aggressive test plan is included which in addition to environmental testing measures bit error rate, latency and antenna patterns. Actual flight tests are planned for the near future on aircraft, long duration balloons and sounding rockets and these results as well as the current status of the project are reported.

Bull, Barton↗