- API data.nasa.gov | Last Updated 2018-09-05T23:02:33.000Z
This data set contains Calibrated data taken by the New Horizons Solar Wind Around Pluto instrument during the pluto cruise mission phase. This is VERSION 3.0 of this data set. Per the original mission plan for cruise operations, the SWAP instrument was off for the first 460+ days of Pluto Cruise. After that the operations were sporadic (just a few days in 2009) and mostly Science, alternating with Channel Electron Multiplier gain tests during Annual CheckOuts. After extensive testing in early 2012, in July of that year the project approved daily science operations for the SWAP and PEPSSI instruments throughout the rest of the cruise to Pluto. The changes in Version 3.0 were re-running of the ancillary data in the data product, updated geometry from newer SPICE kernels, minor editing of the documentation, catalogs, etc., and resolution of liens from the December, 2014 review, plus those from the May, 2016 review of the Pluto Encounter data sets. New observations added with this version (V3.0) include ongoing cruise observations from August, 2014 through January, 2015.
- API data.nasa.gov | Last Updated 2018-09-07T17:46:56.000Z
We propose the CubeSat Radiometer Radio Frequency Interference (RFI) Technology Validation (CubeRRT) mission to demonstrate wideband RFI mitigating backend technologies vital for future space-borne microwave radiometers. Recent passive microwave measurements below 40 GHz have shown an increase in the amount of man-made interference, corrupting geophysical retrievals in a variety of crucial science products, including soil moisture, atmospheric water vapor, sea surface temperature, sea surface winds, and many others. Spectrum for commercial use is becoming increasingly crowded, accelerating demand to open the bands reserved for passive microwave Earth observation and radio astronomy applications to general use. Due to current shared spectrum allocations, microwave radiometers must co-exist with terrestrial RFI sources. For example, the GPM Microwave Imager currently in orbit is impacted by RFI from commercial systems over both land and sea. As these sources expand over larger areas and occupy additional spectrum, it will be increasingly difficult to perform radiometry without an RFI mitigation capability. Co-existence in some cases should be possible provided that a subsystem for mitigation of RFI is included in future systems. Successful RFI mitigation will not only open the possibility of microwave radiometry in any RFI intensive environment, but will also allow future systems to operate over a larger bandwidth resulting in lower measurement noise. This crucial technology is required for the US to maintain a national capability for spaceborne microwave radiometry. Initial progress in RFI mitigation technologies for microwave radiometry has been achieved in the SMAP mission, which is currently operating in space a digital subsystem for this purpose in a 24 MHz bandwidth centered in the protected 1413 MHz band. RFI subsystems for higher frequency microwave radiometry over the range 6-40 GHz however require a larger bandwidth, so that the capabilities of RFI mitigation backends in terms of bandwidth and processing power must also increase. To date, no such wideband subsystem has been demonstrated in space for radiometers operating above 1413 MHz. The enabling technology is a digital Field-Programmable Gate Array-based spectrometer with a bandwidth of 1 GHz or more and capable of implementing advanced RFI mitigation algorithms such as the kurtosis and cross-frequency methods. This technology has a strong ESTO heritage, with the algorithms developed and demonstrated via the Instrument Incubator Program (IIP) and wideband backends developed under other ESTO support. The digital backend is currently at TRL 5, having been successfully tested in an RFI environment, and can be ported easily to a flight-ready firmware. Though the technology can be demonstrated for any frequency band from 1 to 40GHz, we will integrate the backend with a wideband radiometer operating over a 1 GHz bandwidth tunable from 6-40 GHz to demonstrate RFI detection and mitigation in important microwave radiometry bands. Along with a wideband dual-helical antenna, the payload will be integrated with a 6U CubeSat to demonstrate operation of the backend at TRL 7. The payload is expected to operate at a minimum duty-cycle of 25% to be compatible with spacecraft power capacity. Although the spatial resolution to be achieved will be coarse (due to the limited antenna size possible), the goal of demonstrating observation, detection, and mitigation of RFI is achievable in this configuration. The proposed demonstration will act as an immediate risk reduction of new technologies that are necessary for future Earth science missions. The technology will allow newly enabled measurements by operating in previously untenable spectral regions over larger bandwidths. The benefits from the above technology are directly relevant to all future microwave Earth science missions, such as SCLP, GMI follow on, SMAP follow on, and others.
- API data.nasa.gov | Last Updated 2018-09-07T17:42:47.000Z
GLO: A Solar Occultation Instrument Suitable for Constellations of Small Satellites A key challenge in the Earth Science community is to exploit rapidly advancing microsatellite (microsat) technology in the task of providing the myriad of global measurements required to understand key processes. Microsats offer the possibility of inexpensive access to space, but also present payload design challenges resulting from issues such as limited size, weight, and power (SWaP) capacity and pointing capability. We propose a technology demonstration of an instrument we refer to as GLO (GFCR (Gas Filter Correlation Radiometry) Limb solar Occultation) which would measure the vertical profile of atmospheric trace species, with state-of-the-art accuracy. GLO contains 23 Visible Near Infrared (VNIR) and Short Wavelength Infrared (SWIR) spectral bands and measures 10 constituents plus temperature (T), yet fits into a 29x16x16 cm form factor, weighs 5.25 kg, consumes just 28.2 W during observations, and does not levy stringent pointing requirements to the spacecraft. GLO has heritage from HALOE and AIM/SOFIE, both highly successful solar occultation (SO) instruments, but (using recent advances in focal plane array (FPA), and cooler technology) is much smaller and requires substantially less power. In addition, it has significantly improved vertical resolution, pointing, and Upper Troposphere and Lower Stratosphere (UTLS) aerosol and T measurement capability, as well as much reduced sensitivity to aerosol contamination in trace gas retrievals. Novel aspects of the GLO sensor include: use of tactical, but space qualified, imaging FPAs (low cost); GFCR with imaging arrays (precise channel coalignment and registration); proxy GFCR for UTLS H2O and O3 (increased insensitivity to aerosol contamination in the UTLS); and VNR plus SWIR aerosol extinction measurement capability (aerosol extinction plus bulk properties). While GLO could have many applications (including, e.g., an inexpensive stratospheric monitoring sensor), we conceived it to probe a key but poorly documented component of the climate system, the UTLS, in a mission concept referred to as SOCRATES (Solar Occultation Constellation for Retrieving Aerosols and Trace Element Species). The goal of SOCRATES is to quantify the role of the UTLS in climate change. For SOCRATES, GLO measures T, radiatively active gases (H2O, O3, CH4, N2O), aerosols, and transport tracers (HDO, CO, HCN, HF, HCl) with vertical resolution (<1 km) and geographic sampling required for UTLS radiative forcing calculations. Satellite SO instruments provide high vertical resolution and precision, but sample only 2 latitudes per orbit. To mitigate this shortcoming, SOCRATES consists of a constellation of 6 GLO sensors, deployed from a single launch vehicle into orbits with slightly different mean altitudes. The dispersing orbits provide the required spatial and temporal sampling, with coverage from ±65° latitude. We have shown that the SOCRATES GLO constellation (6 sensors & microsats) meets all measurement complement, accuracy, vertical resolution, and spatial sampling requirements, and can be fabricated, launched, and operated in a 26-month mission within the NASA Earth Venture Mission cost capped budget. Under this proposal, we will refine the design and fabricate a complete prototype GLO sensor [identical in form, fit and function to the SOCRATES/GLO sensor except for the use of non-space qualified (but functionally identical) components], perform functional and environmental tests to confirm it can meet SOCRATES measurement requirements, and validate the instrument concept through ground and balloon-based observations. This will provide a nearly complete demonstration of the GLO technology, and measurement approach and capabilities. The goal is to raise the GLO sensor technique and design from TRL 4 to TRL 6, providing risk reduction for the SOCRATES mission concept, and for the use of GLO in other missions.
Wideband Autocorrelation Radiometer Receiver Development and Demonstration for Direct Measurement of Terrestrial Snow and Ice Accumulationdata.nasa.gov | Last Updated 2018-09-07T17:43:06.000Z
The seasonal terrestrial snow pack is an important source of water for many parts of the globe. Snow's high albedo, relative to the terrain in the absence of snow, is an important driver of Earth's energy balance, and long term changes to the statistics of the snow pack's properties are both a consequence and a cause of climate change. The global quantification of the amount of water in the snow pack reservoir is a long term objective of NASA's Earth Science Division. Thus far, the primary means of quantifying the amount of snow on the ground has been via the differential scatter-darkening mechanism, such as the 19 and 37 GHz brightness difference. While a 35+ year time series of passive microwave satellite data has been made, progress in understanding the scatter-darkened brightness signature of snow continues, especially for forested areas where vegetation scattering confounds the signature. This proposal looks to advance an alternative approach to using passive microwave to measure the snow accumulation. Wideband autocorrelation radiometry (WiBAR) is a technique wherein the electromagnetic propagation time across a layered media, such as snow pack or lake ice, can be remotely sensed. Thermal emission from the ground under the snow pack propagates up through the snow pack to the receiver. When the upper and lower surfaces of the snow pack are locally smooth, which is true at sufficiently long wavelengths, additional paths result from the reflection of the upward traveling wave from first the upper and then the lower surface of the snow pack. Arriving at the antenna, these waves are identical except for their amplitude and the time lag associated with the extra transit of the snow pack. This time lag is the observable. For sufficiently long wavelengths, the snow snow grains that cause the scattering are sufficiently deep in the Rayleigh region so as to be of minor importance. Unlike scatter darkening, where the microscopic properties of snow dominate the signal and the desired macroscopic properties are secondary, for WiBAR, the macroscopic properties of the snow depth is the most important parameter determining the signal, modified by the density (and thus it measures SWE), and the microscopic properties, responsible for the scattering, reduce the signal strength but do not alter the quantification of the accumulation. The bandwidth of the radiometer determines the minimum vertical extent that is observable. A wide bandwidth (several gigahertz) is desired for the relatively shallow snow covers encountered on Earth. We have demonstrated that this signal exists and can be observed both for a snow pack and for a fresh-water lake ice pack with ground-based observations. We have done this with a spectrum analyzer functioning as the radiometer receiver back-end: in the frequency domain, the delayed ray interferes with the direct ray to produce constructive maxima and destructive minima in the brightness spectra. But this technique is inherently slow, as the number of samples required is high and the instantaneous bandwidth is low. This frequency-domain approach is much too slow for spaceborne or even airborne observation. These observations also confirm the robustness of the approach to radio-frequency interference (RFI): since the observable is a time-delay and not a brightness magnitude, the narrow-band RFI does not mask the broadband WiBAR signature. We propose to develop a radiometer back-end that observes the entire spectrum of interest simultaneously, which will greatly reduce the observation time, possibly down to the order of milliseconds, which would make observations from a moving platform possible. We will then demonstrate the technological advancement in a direct comparison to the spectrum analyzer-based receiver measurement in a laboratory setting.
Multi-Band Radiometric Imager Utilizing Uncooled Microbolometer Arrays with Piezo Backscan for Earth Observation Mission Applicationsdata.nasa.gov | Last Updated 2018-09-07T17:43:41.000Z
DRS Technologies takes pleasure in presenting this Multi-Band Uncooled Radiometer Imager (MURI) proposal for the Instrument Incubator Program (IIP) that will provide improved radiometric imaging performance, substantially reduce the cost, complexity, and development time for future Polar Orbiting earth observation imaging radiometer sensors. Our proposed solution leverages conventional, low cost uncooled microbolometers with a compact piezo driven backscan and our patented TCOMP algorithms for improved radiometric accuracy and stability. Our solution eliminates the need for cryogenic cooling, solves the problem of image smear associated with the bolometers relatively long time constant, while simultaneously ensuring low NEDT. The objective of the DRS proposed MURI program is to demonstrate that modern, low cost, large area microbolometer FPAs can be utilized to provide narrow band radiometrically accurate imaging in 8 LWIR bands for Earth Science applications. The potential earth science applications for this technology are Land Surface Climatology, measurement of soil moisture content, measurement of Ecosystem Dynamics, Volcano Monitoring, Hazard monitoring, Geology and Soils. On the IIP Program, DRS plans to design, build, test and demonstrate an uncooled microbolometer breadboard sensor hardware for earth observation. Our Science partner, Rochester Institute of Technology (RIT), will support the airborne data collects, radiometric data analysis and comparison to LANDSAT 8 for a “truth reference” and the science implementation aspect of the instrument data collects. DRS/RIT will collect airborne data for three primary applications in 8 spectral bands. The first will assess initial data quality and calibration with known targets deployed, the second will demonstrate scientific products available over vegetative and urban environments, while the third will demonstrate important aspects of volcano monitoring. One key technological solution is the use of a piezo back-scan stage located at the image plane. The piezo drive velocity will be set to match the aircraft ground velocity during image collection, such that the image smear from the bolometer’s long time constant is eliminated. This is critical for the use of a standard microbolometer array which typically has ~14msec time constant. Another key feature is the real-time radiometric correction that will occur during flight to account for the instrument and optics temperature changes during operation. This methodology is being utilized by DRS in commercial radiometers and will be implemented here to account for instrument/optics temperature changes and their contribution to radiometric error. This is a dramatic shift from prior radiometers built for earth observation in that those instruments typically cool the optics to reduce radiometric error. We envision a space instrument using 10 FPAs, with up to 12 spectral filters to cover a ground swath width of 310km from a 705km altitude orbit and a 100m GSD. For this airborne demo we plan to utilize 4 FPAs with 8 spectral band filters to demonstrate the key technology within the more limited IIP program budget. For an airborne demo, using 120mm EFL f/1 optics at 15,000ft altitude, will have a 0.65m GSD with two parallel swath widths of 414km separated by a gap of 619m. We will show direct applicability to a space instrument and how it is easily scalable using a stagger butted array approach. Much of the same hardware could be utilized on a space version of this instrument. Period of performance of this IIP project is expected to be 36 months. The first year of the program will involve the design of the instrument hardware, the second year will be the build of the components integration and assembly of the instrument and the third year will be laboratory test of the instrument and airborne field testing. Entry level TRL for this instrument is 3; exit level TRL at the end of year 3 will be 6.
- API data.nasa.gov | Last Updated 2018-07-19T14:21:42.000Z
To achieve the capability to affordably produce scores of nano-spacecraft for envisioned constellation missions, a new manufacturing process is needed to reduce the time and cost of fabricating and testing the nanosats. However, to achieve substantial savings, a fundamental paradigm shift in how spacecraft are built must be made. Current spacecraft are built with the same processes and procedures used in the 1960?s, whereas electronics technology has gone far beyond that of the early days. So while the size of satellites has steadily decreased, the manufacturing time has not experienced similar reductions. Given that labor to build a satellite remains the single largest element of cost, the opportunity remains to dramatically shorten program schedules and lower cost through the infusion of new techniques and innovative processes in the construction of structures, electronics, harnessing and most importantly the testing process. AeroAstro proposes to set aside the conventional rule book and explore a broad range of Design for Manufacture material and process innovations that could lead to a dramatic shortening of the micro/nano-satellite manufacturing timeline with concomitant savings in unit manufacturing cost.
- API data.nasa.gov | Last Updated 2018-07-19T07:46:35.000Z
Structural health monitoring is critical capability for NASA, and it is required for launch vehicles, space vehicles, re-entry vehicles, vehicle pressure systems, Space Station, as well as in flight research. Health monitoring systems need to have fast and robust data acquisition and management, low volume, minimal intrusion, and high accuracy and reliability. Armstrong Flight Research Center has developed a revolutionary 4-fiber interrogation system for Fiber Optic Smart Structures (FOSS) sensor networks interrogation. This system meets the required specifications on the sensing side, however, its size, weight, power consumption, fragility and cost make it prohibitive for the massive deployment into air vehicles. In this program, we are proposing to develop and integrate all optical functions needed to enable next generation of miniaturized, low-cost NASA's FOSS interrogator systems. Through innovative photonic integration of key functions, and hybrid packaging using interposer technology, we anticipate that the size of the existing system will be reduced by two and cost by one order of magnitude. This, in turn, will fulfill one of the key requirements of the solicitation, yielding a miniaturized fiber optic measurement system with low power suitable for migration into platforms spanning from launch vehicles, reentry vehicles, to UAS platforms or aviation.
- API data.nasa.gov | Last Updated 2018-07-19T05:28:43.000Z
This dataset contains RAW DATA of the STEINS flyby Phase from 4 August 2008 until 5 September 2008. The closest approach (CA) took place on 5 September 2008
- API data.nasa.gov | Last Updated 2018-07-19T05:26:25.000Z
This data set includes wideband waveform measurements from the Galileo plasma wave receiver obtained during Jupiter orbital operations. These data were obtained during selected observation periods near perijove, satellite encounters and other select times. These measurements are electric waveforms obtained by rapidly sampling the potential at the input to the receiver from the electric dipole antenna. The sample rates are 201,600/s, 25,200/s, or 3,150/s taken through bandpass filters of 80, 10, or 1 kHz, respectively.
- API data.nasa.gov | Last Updated 2018-07-19T08:25:03.000Z
Accurate predictive modeling of certain atmospheric chemical phenomena (i.e. volcano plumes, smog, gas clouds, wildfire smoke, etc.) suffers from a dearth of information, largely due to the fact that the dynamic qualities of the phenomenon evade accurate data collection. In situ measurements are currently made through the use of ground sensors and dropsondes. ?Ground sensors, such as seismometers, tiltmeters, in-ground gas monitors and near-field remote sensings instruments[,]? have limited measurement density and provide only information about atmospheric boundary conditions. Dropsondes can provide measurements over the entire vertical profile, but are limited to sampling over a small time period. In situ measurements can be augmented with satellite-based remote sensing systems, such as ASTER, MODIS, AIRS and OMI, however, satellite-based data suffers from its relatively small spatial density and limited frequency of measurement. A need exists for additional targeted in situ data from volcanic ash clouds, particularly to assess ...particle size distribution, ash cloud height, and ash cloud thickness including spatial (horizontal and vertical) and temporal variability of ash concentration. The proposed innovation, the SuperSwift XT, will meet NASA's need to enhance [the] performance and utility of NASA's airborne science fleet by providing a durable, terrain-following UAS that will be adapted for use in harsh environments containing environmental phenomena that impacts societal activity (i.e. volcanic emissions impacting the safety of passenger aviation). The sUAS will provide targeted, in situ observations from previously inaccessible regions that can significantly advance NASA?s goal of safe, efficient growth in global aviation by aiding in the collection of scientific data from which predictive Volcanic Ash Transport and Dispersion models (VATD) used to inform air traffic management systems.