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OMI/Aura Level 1B VIS Zoom-in Geolocated Earthshine Radiances 1-orbit L2 Swath 13x12 km V003
nasa-test-0.demo.socrata.com | Last Updated 2015-07-20T04:54:21.000ZThe Level-1B (L1B) Radiance Product OML1BRVZ (Version-3) from the Aura-OMI is now available (http://disc.gsfc.nasa.gov/Aura/OMI/oml1brvz_v003.shtml) to public from the NASA GSFC Earth Sciences Data and Information Services Center (GES DISC). OMI calibrated and geolocated radiances for the channels in the UV1 (264-311 nm), UV2 (307-383 nm)and VIS(349-504) regions, spectral irradiances, calibration measurements, and all derived geophysical atmospheric products are archived at the NASA Goddard DAAC. (The shortname for this OMI Level-1B Product is OML1BRVZ) The lead algorithm scientist for this product is Dr. Marcel Dobber from the KNMI. The OMI Level 1B Visible Radiance Zoom-in Product OML1BRVZ contains geolocated Earth view spectral radiances from the VIS channel detectors in the wavelength range of 349 to 504 nm. The product contains the measurements that are taken once a month using the spatial zoom-in measurement modes (30 pixels covering 750 km swath width). In spatial zoom in mode the nadir ground pixel size is 13 x 12 km2 and measurements are available only for the wavelengths 306 to 432 nm. OML1BRVZ files are stored in EOS Hierarchical Data Format (HDF-EOS 2.4) which is based on HDF4. The radiance for the earth measurements (also referred as signal) and its precision are stored as a 16 bit mantissa and an 8-bit exponent. The signal can be computed using the equation: signal = signal_mantissa x 10 exponent . For the precision, the same exponent is used as for the signal. Each file contains data from the day lit portion of an orbit (~53 minutes) and is roughly 570 MB in size. There are approximately 14 orbits per day.
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Planning for Planetary Science Mission Including Resource Prospecting Project
nasa-test-0.demo.socrata.com | Last Updated 2015-07-20T05:33:43.000ZAdvances in computer-aided mission planning can enhance mission operations and science return for surface missions to Mars, the Moon, and beyond. While the innovations envisioned by this program are broadly applicable, they serve an immediate and urgent need for missions to prospect for volatiles at the lunar poles (i.e., the NASA Lunar Resource Prospector Mission, currently in Phase A). These missions must be rapid and precise, covering multiple kilometers in approximately 10-12 Earth days to complete mission objectives in one lunar light cycle. This calls for the ability to drive intentionally and efficiently to precise drilling destinations. Polar operations encounter low angle lighting; this creates shadows which confront robot operations with challenges in power production, thermal control, and operator situational awareness. This demands robust path planning for efficient mission planning and execution. The proposed work develops a computer-aided mission planning tool that balances the competing demands of efficient routes, scientific information gain, and rover constraints (e.g., kinematics, communication, power, thermal, and terrainability) to generate and analyze optimized routes between sequences of locations. Planner-computed statistics about the set of viable paths enable mission planners, scientists, and operators to efficiently select routes considering a range of priorities including risk, duration, and science return. This planner will serve an invaluable role in preplanning missions and as a tool for rapidly understanding the impact of changes in mission profile during the mission execution.
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Including the effects of a harsh radiation environment in the simulation and design of nanoelectronic devices and circuits Project
nasa-test-0.demo.socrata.com | Last Updated 2015-07-20T05:31:59.000ZNanoelectronic devices, and circuits based on such devices, are expected to be more susceptible to the effects of radiation than the previous generation of devices and circuits. Circuits that can operate in harsh radiation environments are essential components of commercial satellite communications systems, space exploration vehicles, and national defense systems. Hence there is a critical need to understand and quantify the effects of radiation on the present and next generation of nanoelectronic circuits, and to develop methods to render such circuits insensitive to radiation. In this project we intend to identify and characterize (as a function of device dimension if possible) the deleterious effects of radiation on nanoscale devices. More importantly, we intend to build on the standard models, which describe the effects of radiation, and develop software that would enable the modeling and simulation of radiation effects. First we will consider conventional nanoelectronic devices --- that is those where charge transport is based on the usual principles of drift and diffusion. Then a tool for the effects of radiation on single electron transistors and amplifiers (including those based on carbon nanotubes) would also be developed. Using the software, methods to mitigate the effects of radiation by rad-hard designs will be examined.
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Wide Temperature Range DC-DC Boost Converters for Command/Control/Drive Electronics Project
nasa-test-0.demo.socrata.com | Last Updated 2015-07-20T05:23:03.000ZWe shall develop wide temperature range DC-DC boost converters that can be fabricated using commercial CMOS foundries. The boost converters will increase the low voltage supply (~ 0.7 to 3V) of an advanced CMOS integrated circuit to the higher values (3-10V) required for integrated command/control/drive electronics for sensors, actuators and instrumentation. The high voltage capability is a result of our patented, CMOS compatible transistor technology that is radiation tolerant (TID>1 MRad), SEL immune and capable of wide temperature range operation (-196C to +150C). This new transistor technology has been demonstrated at multiple foundries and advanced device models are available for circuit design and simulation. The DC-DC boost converters will be integrated directly with the CMOS components to provide a single chip solution, greatly reducing the number of active and passive components that would otherwise be required. By allowing enhanced voltage operation in future CMOS technology nodes we will be avoiding many of the obsolescence problems facing NASA missions that are dependent upon commercial electronics. The circuits will be designed to operate in low temperature environments that experience wide temperature swings such as those found on the moon, Mars, Titan, Europa and comets.
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SAFARI 2000 Surface Atmospheric Radiative Transfer (SMART), Dry Season 2000
nasa-test-0.demo.socrata.com | Last Updated 2015-07-19T08:43:42.000ZSurface-sensing Measurements for Radiative Transfer (SMART) and Chemical, Optical, and Microphysical Measurements of In-situ Troposphere (COMMIT) consist of a suite of instruments that measure (both in-situ and by remote sensing) parameters that help to characterize, as completely as possible, constituents of the atmosphere at a given location. SMART and COMMIT are mobile systems that can be deployed to locations that exhibit interesting atmospheric phenomena. This allows investigators to participate in coordinated measurement campaigns, such as SAFARI 2000.The SMART instruments were deployed to the Skukuza Airport from August 15 to September 17, 2000 to take part in the SAFARI 2000 Dry Season Aircraft Campaign. The SMART-COMMIT mission is designed to pursue the following goals: Earth Observing System (EOS) validation; innovative investigations; and long-term atmospheric monitoring. The results reported in this data set are for the following instruments deployed and measurements recorded at the Skukuza Airport site within the Kruger National Park: several broadband radiometers, for global, diffuse, direct downward solar irradiance and global infrared downward irradiance; meteorological sensors, for surface air temperature, pressure, relative humidity, and wind; and a Solar Spectral Flux Radiometer (NASA Ames) for spectral solar downward irradiance.
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NLDAS VIC Land Surface Model L4 Monthly Climatology 0.125 x 0.125 degree V002
nasa-test-0.demo.socrata.com | Last Updated 2015-07-19T08:29:26.000ZAbstract: This data set contains a series of land surface parameters simulated from the VIC land-surface model (LSM) for Phase 2 of the North American Land Data Assimilation System (NLDAS-2). The data are in 1/8th degree grid spacing. The temporal resolution is monthly, ranging from January to December. The file format is WMO GRIB-1. The NLDAS-2 monthly climatology data are the monthly data averaged over the thirty years (1980-2009) of the NLDAS-2 monthly data. Brief description about the NLDAS-2 hourly and monthly VIC LSM data can be found from the GCMD DIFs for GES_DISC_NLDAS_VIC0125_H_V002 and GES_DISC_NLDAS_VIC0125_M_V002 at http://gcmd.gsfc.nasa.gov/getdif.htm?GES_DISC_NLDAS_VIC0125_H_V002 and http://gcmd.gsfc.nasa.gov/getdif.htm?GES_DISC_NLDAS_VIC0125_M_V002. Details about the NLDAS-2 configuration of the VIC LSM can be found in Xia et al. (2012). The version of the VIC model for the NLDAS-2 VIC data available from the NASA GES DISC is VIC-4.0.3; this version of the VIC model is the same as used in Sheffield et al. (2003). The NLDAS-2 VIC monthly climatology data contain forty-three fields. The data set applies a user-defined parameter table to indicate the contents and parameter number. The GRIBTAB file (http://disc.sci.gsfc.nasa.gov/hydrology/grib_tabs/gribtab_NLDAS_VIC.002.txt) shows a list of parameters for this data set, along with their Product Definition Section (PDS) IDs and units. For information about the vertical layers of the Soil Moisture Content (PDS 086), Soil Temperature (PDS 085), and Liquid Soil Moisture Content (PDS 151), please see the README Document at ftp://hydro1.sci.gsfc.nasa.gov/data/s4pa/NLDAS/README.NLDAS2.pdf or the GrADS ctl file at ftp://hydro1.sci.gsfc.nasa.gov/data/gds/NLDAS/NLDAS_VIC0125_MC.002.ctl.
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Extreme Temperature, Rad-Hard Power Management ASIC Project
nasa-test-0.demo.socrata.com | Last Updated 2015-07-20T05:14:50.000ZRidgetop Group will design a rad-hard Application Specific Integrated Circuit (ASIC) for spacecraft power management that is functional over a temperature range of -230 to +130 <SUP>o</SUP>C. This ASIC is intended to work in conjunction with a Fuel Cell power system and battery back-up to provide uninterrupted power to critical modules in Space. Ridgetop will combine Radiation Hardening (RH) techniques with Large Scale Integration (LSI) methodologies to build a power management system for spacecraft applications onto a single monolithic circuit. The significance of this innovation is a single reliable component (ASIC) that will meet platform requirements for high voltage, wide operating temperature range, and radiation tolerance (minimum 100 krads Total Ionizing Doze (TID), 100 MeVcm2/mg Single Event Latchup (SEL). During phase 1, we will select two functional blocks from within a representative NASA power management system as test cases. Designs for these blocks will be developed and validated through SPICE circuit and radiation simulations, using technology files provided by a commercial foundry. In phase 2, Ridgetop will deliver working prototype integrated circuits (ICs) that meet and exceed the above requirements.
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TRMM Precipitation Radar (PR) Level 2 Rainfall Rate and Profile Product (TRMM Product 2A25) V7
nasa-test-0.demo.socrata.com | Last Updated 2015-07-19T08:53:20.000ZThe TRMM Precipitation Radar (PR), the first of its kind in space, is an electronically scanning radar, operating at 13.8 GHz that measures the 3-D rainfall distribution over both land and ocean, and defines the layer depth of the precipitation. The objectives of 2A25 is to correct for the rain attenuation in measured radar reflectivity and to estimate the instantaneous three-dimensional distribution of rain from the TRMM Precipitation Radar (PR) data. The estimates of attenuation-corrected radar reflectivity factor and rainfall rate are given at each resolution cell of the PR. The estimated near-surface rainfall rate and average rainfall rate between the two pre-defined altitudes (2 and 4 km) are also calculated for each beam position. 2A25 basically uses a hybrid of the Hitschfeld-Bordan method and the surface reference method to estimate the vertical true radar reflectivity (Z) profile. (The hybrid method is described in Iguchi and Meneghini (1994)). The vertical rain profile is then calculated from the estimated true Z profile by using an appropriate Z-R relationship. The attenuation correction is, in principle, based on the surface reference method. This method assumes that the decrease in the apparent surface cross section (delta sigma-zero) is caused by the propagation loss in rain. The coefficient a in the k-Z relationship, k=a Z**b, is adjusted in such a way that the path-integrated attenuation (PIA) estimated from the measured Zm-profile will match the delta sigma-zero. The attenuation correction of Z is carried out by the Hitschfeld-Bordan method with the modified a. Since a is adjusted, this type of surface reference method is called the a-adjustment method. The a-adjustment method assumes that the discrepancy between the PIA estimate from delta sigma-zero and that from the measured Zm-profile can be attributed to the inappropriate choice of a values, which may vary depending on the raindrop size distribution and other conditions. It assumes that the radar is properly calibrated and that the measured Zm has no error. In order to avoid inaccuracies in the attenuation correction when rain is weak, a hybrid of the surface reference method and the Hitschfeld-Bordan method is used (Iguchi and Meneghini, 1994). The PIA is first estimated from the precipitation echo alone. The weight given by the hybrid method to the PIA estimate from the surface reference increases as the attenuation estimate increases. When rain is very weak and the attenuation estimate is small, the PIA estimate from the surface reference is effectively neglected. With the introduction of the hybrid method, the divergence associated with the Hitschfeld-Bordan method is also prevented. One major difference from the method described in the above reference is that, in order to deal with the beam-filling problem, a non-uniformity parameter is introduced and is used to correct the bias in the surface reference arising from the horizontal non-uniformity of rain field within the beam. Since radar echoes from near the surface are contaminated by the mainlobe clutter, the rain estimate at the lowest point in the clutter-free region is given as the near-surface rainfall rate for each angle bin. Spatial coverage is between 38 degrees North and 38 degrees South, owing to the 35 degree inclination of the TRMM satellite. This orbit provides extensive coverage in the tropics and allows each location to be covered at a different local time each day, enabling the analysis of the diurnal cycle of precipitation. There are, in general, 9150 scans along the orbit, with each scan consisting of 49 rays. The scan width is about 220 km. The data are stored in the Hierarchical Data Format (HDF), which includes both core and product specific metadata applicable to the PR measurements. A fi...
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BUV/Nimbus-04 Ozone (O3) Profile and Total Column Ozone Monthly L3 Global 5.0deg Lat Zones V1
nasa-test-0.demo.socrata.com | Last Updated 2015-07-20T05:06:00.000ZThe Solar Backscattered Ultra Violet (SBUV) from Nimbus-4 Level-3 monthly zonal mean (MZM) product (BUVN04L3zm) is derived from the Level-2 retrieved ozone profiles. Ozone retrievals are generated from the v8.6 SBUV algorithm. A Level-3 MZM file computes zonal means covering 5 degree latitude bands for each calendar month. For this product there are 72 months of data from May 1970 through April 1976. There are a total of 36 latitudinal bands, 18 in each hemisphere. Profile data are provided at 21 layers from 1013.25, 639.318, 403.382,254.517, 160.589, 101.325,63.9317, 40.3382, 25.4517, 16.0589, 10.1325, 6.39317,4.03382, 2.54517, 1.60589, 1.01325,0.639317, 0.403382, 0.254517, 0.160589 and 0.101325 hPa (measured at bottom of layer). NOTE: Some profiles have 20 layers and do not report the top most layer. Mixing ratios are reported at 15 layers from 0.5, 0.7, 1.0, 1.5, 2.0, 3.0, 4.0, 5.0, 7.0, 10.0, 15.0, 20.0, 30.0, 40.0 and 50.0 hPa (measured at middle of layer). The MZM product averages retrievals that meet the criteria for a good retrieval as determined by error flags in the Level 2 data. A good retrieval is defined as satisfying the following conditions: 1) Profile Error Flag = 0 or 1 (0 = good retrieval; 1 = solar zenith angle > 84 deg.) 2) Total Error Flags = 0, 1, 2 or 5 (0 = good retrieval; 1 = not used; 2 = solar zenith angle > 84 deg; large discrepancy between profile total and best total ozone) NOTE - Total error flag = 5 is anomalously applied at high latitudes and high solar zenith angle where B-Pair total ozone estimate is not as reliable as profile under these conditions. This error flag may be removed in future version of algorithm. The zonal means computed for each month are screened according to the following statistical criteria: 1) number of good retrievals for the month greater than or equal to 2/3 of the samples for a nominal month. 2) mean latitude of good retrievals less than or equal to 1 degree from center of latitude band. 3) mean time of good retrievals less than or equal to 4 days from center of month (i.e., day = 15)
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BUV/Nimbus-04 Ozone (O3) Profile and Total Column Ozone Monthly L3 Global 5.0deg Lat Zones V1
nasa-test-0.demo.socrata.com | Last Updated 2015-07-20T05:06:01.000ZThe Solar Backscattered Ultra Violet (SBUV) from Nimbus-4 Level-3 monthly zonal mean (MZM) product (BUVN04L3zm) is derived from the Level-2 retrieved ozone profiles. Ozone retrievals are generated from the v8.6 SBUV algorithm. A Level-3 MZM file computes zonal means covering 5 degree latitude bands for each calendar month. For this product there are 72 months of data from May 1970 through April 1976. There are a total of 36 latitudinal bands, 18 in each hemisphere. Profile data are provided at 21 layers from 1013.25, 639.318, 403.382,254.517, 160.589, 101.325,63.9317, 40.3382, 25.4517, 16.0589, 10.1325, 6.39317,4.03382, 2.54517, 1.60589, 1.01325,0.639317, 0.403382, 0.254517, 0.160589 and 0.101325 hPa (measured at bottom of layer). NOTE: Some profiles have 20 layers and do not report the top most layer. Mixing ratios are reported at 15 layers from 0.5, 0.7, 1.0, 1.5, 2.0, 3.0, 4.0, 5.0, 7.0, 10.0, 15.0, 20.0, 30.0, 40.0 and 50.0 hPa (measured at middle of layer). The MZM product averages retrievals that meet the criteria for a good retrieval as determined by error flags in the Level 2 data. A good retrieval is defined as satisfying the following conditions: 1) Profile Error Flag = 0 or 1 (0 = good retrieval; 1 = solar zenith angle > 84 deg.) 2) Total Error Flags = 0, 1, 2 or 5 (0 = good retrieval; 1 = not used; 2 = solar zenith angle > 84 deg; large discrepancy between profile total and best total ozone) NOTE - Total error flag = 5 is anomalously applied at high latitudes and high solar zenith angle where B-Pair total ozone estimate is not as reliable as profile under these conditions. This error flag may be removed in future version of algorithm. The zonal means computed for each month are screened according to the following statistical criteria: 1) number of good retrievals for the month greater than or equal to 2/3 of the samples for a nominal month. 2) mean latitude of good retrievals less than or equal to 1 degree from center of latitude band. 3) mean time of good retrievals less than or equal to 4 days from center of month (i.e., day = 15)