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  • Instrumentation and Photography  (8)
  • Acids  (1)
  • 2010-2014  (9)
  • 2005-2009
  • 1965-1969
  • 1930-1934
  • 1
    Publication Date: 2010-02-09
    Description: Although the notion of an early origin and diversification of life on Earth during the Archaean eon has received increasing support in geochemical, sedimentological and palaeontological evidence, ambiguities and controversies persist regarding the biogenicity and syngeneity of the record older than Late Archaean. Non-biological processes are known to produce morphologies similar to some microfossils, and hydrothermal fluids have the potential to produce abiotic organic compounds with depleted carbon isotope values, making it difficult to establish unambiguous traces of life. Here we report the discovery of a population of large (up to about 300 mum in diameter) carbonaceous spheroidal microstructures in Mesoarchaean shales and siltstones of the Moodies Group, South Africa, the Earth's oldest siliciclastic alluvial to tidal-estuarine deposits. These microstructures are interpreted as organic-walled microfossils on the basis of petrographic and geochemical evidence for their endogenicity and syngeneity, their carbonaceous composition, cellular morphology and ultrastructure, occurrence in populations, taphonomic features of soft wall deformation, and the geological context plausible for life, as well as a lack of abiotic explanation falsifying a biological origin. These are the oldest and largest Archaean organic-walled spheroidal microfossils reported so far. Our observations suggest that relatively large microorganisms cohabited with earlier reported benthic microbial mats in the photic zone of marginal marine siliciclastic environments 3.2 billion years ago.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Javaux, Emmanuelle J -- Marshall, Craig P -- Bekker, Andrey -- England -- Nature. 2010 Feb 18;463(7283):934-8. doi: 10.1038/nature08793. Epub 2010 Feb 7.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Geology, University of Liege, 17 allee du 6 Aout B18, Liege 4000, Belgium. ej.javaux@ulg.ac.be〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/20139963" target="_blank"〉PubMed〈/a〉
    Keywords: Acids ; Bacteria/chemistry/cytology/isolation & purification/metabolism ; Carbon/analysis/chemistry ; Carbon Isotopes ; *Ecosystem ; Eukaryotic Cells/chemistry/cytology ; *Fossils ; Geologic Sediments/*microbiology ; History, Ancient ; Oceans and Seas ; Organic Chemicals/*analysis/chemistry ; *Phylogeny ; Reproducibility of Results ; Seawater/*microbiology ; South Africa ; Spectrum Analysis, Raman ; Sunlight
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
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  • 2
    Publication Date: 2019-07-13
    Description: The Geostationary Fourier Transform Spectrometer (GeoFTS) is an imaging spectrometer designed for an earth science mission to measure key atmospheric trace gases and process tracers related to climate change and human activity. The GeoFTS instrument is a half meter cube size instrument designed to operate in geostationary orbit as a secondary "hosted" payload on a commercial geostationary satellite mission. The advantage of GEO is the ability to continuously stare at a region of the earth, enabling frequent sampling to capture the diurnal variability of biogenic fluxes and anthropogenic emissions from city to continental scales. The science goal is to obtain a process-based understanding of the carbon cycle from simultaneous high spatial resolution measurements of carbon dioxide (CO2), methane (CH4), carbon monoxide (CO), and chlorophyll fluorescence (CF) many times per day in the near infrared spectral region to capture their spatial and temporal variations on diurnal, synoptic, seasonal and interannual time scales. The GeoFTS instrument is based on a Michelson interferometer design with a number of advanced features incorporated. Two of the most important advanced features are the focal plane arrays and the optical path difference mechanism. A breadboard GeoFTS instrument has demonstrated functionality for simultaneous measurements in the visible and IR in the laboratory and subsequently in the field at the California Laboratory for Atmospheric Remote Sensing (CLARS) observatory on Mt. Wilson overlooking the Los Angeles basin. A GeoFTS engineering model instrument is being developed which will make simultaneous visible and IR measurements under space flight like environmental conditions (thermal-vacuum at 180 K). This will demonstrate critical instrument capabilities such as optical alignment stability, interferometer modulation efficiency, and high throughput FPA signal processing. This will reduce flight instrument development risk and show that the GeoFTS design is mature and flight ready.
    Keywords: Instrumentation and Photography
    Type: IEEE Aerospace Conference; Mar 03, 2012 - Mar 10, 2012; Big Sky, MT; United States
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  • 3
    Publication Date: 2019-07-13
    Description: No abstract available
    Keywords: Instrumentation and Photography
    Type: IEEE Aerospace Conference; Mar 05, 2011 - Mar 12, 2011; Big Sky, MT; United States
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  • 4
    Publication Date: 2019-07-13
    Description: No abstract available
    Keywords: Instrumentation and Photography
    Type: 2012 IEEE Aerospace Conference; Mar 03, 2012 - Mar 10, 2012; Big Sky, MT; United States
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  • 5
    Publication Date: 2019-07-13
    Description: Communication with remote exploration spacecraft is often intermittent and bandwidth is highly constrained. Future missions could use onboard science data understanding to prioritize downlink of critical features [1], draft summary maps of visited terrain [2], or identify targets of opportunity for followup measurements [3]. We describe a generic approach to classify geologic surfaces for autonomous science operations, suitable for parallelized implementations in FPGA hardware. We map these surfaces with texture channels - distinctive numerical signatures that differentiate properties such as roughness, pavement coatings, regolith characteristics, sedimentary fabrics and differential outcrop weathering. This work describes our basic image analysis approach and reports an initial performance evaluation using surface images from the Mars Exploration Rovers. Future work will incorporate these methods into camera hardware for real-time processing.
    Keywords: Instrumentation and Photography
    Type: International Symposium on Artificial Intelligence Robotics and Automation in Space; Sep 04, 2012 - Sep 06, 2012; Turin; Italy
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  • 6
    Publication Date: 2019-07-13
    Description: The Xilinx Virtex-5QV is a new Single-event Immune Reconfigurable FPGA (SIRF) device that is targeted as the spaceborne processor for the NASA Decadal Survey Aerosol-Cloud-Ecosystem (ACE) mission's Multiangle SpectroPolarimetric Imager (MSPI) instrument, currently under development at JPL. A key technology needed for MSPI is on-board processing (OBP) to calculate polarimetry data as imaged by each of the 9 cameras forming the instrument. With funding from NASA's ESTO1 AIST2 Program, JPL is demonstrating how signal data at 95 Mbytes/sec over 16 channels for each of the 9 multi-angle cameras can be reduced to 0.45 Mbytes/sec, thereby substantially reducing the image data volume for spacecraft downlink without loss of science information. This is done via a least-squares fitting algorithm implemented on the Virtex-5 FPGA operating in real-time on the raw video data stream.
    Keywords: Instrumentation and Photography
    Type: ESTF-2011 (Earth Science Technology Forum); Jun 21, 2011 - Jun 23, 2011; Pasadena, CA; United States
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  • 7
    Publication Date: 2019-07-13
    Description: No abstract available
    Keywords: Instrumentation and Photography
    Type: Earth Science Technology Forum (ESTF) 2011; Jun 21, 2011; Pasadena, CA; United States
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  • 8
    Publication Date: 2019-07-13
    Description: JPL is currently developing the multi-angle spectro-polarimetric imager (MSPI), targeted for the Aerosol-Cloud-Ecosystems (ACE) mission, as defined in the National Academies 2007 Decadal Survey. In preparation for the space instrument, the MSPI team has built two incremental camera systems (Ground- and Air-MSPI) to improve understanding of the proposed architecture. Ground-MSPI is a gimballed instrument used primarily for stationary observation and characterization of the imager and optics. The ER-2 based Air-MSPI operates in a step-and-stare mode, providing multi-angle imaging of a static target. This mode-of-operation simulates the observation scenario of the space instrument. Physically, MSPI is a pushbroom camera with a specialized frontend. Before imaging, light entering the camera passes through a pair of photoelastic modulators and a set of pattern polarizers. These optical elements act on the light to make polarimetric extraction computationally feasible. Calculating polarimetric parameters from the imager's data stream requires a real-time least-squares computation that produces coefficients of a truncated time-series expansion of the image. As reported in, the data processing algorithm can operate in real-time on a Xilinx Virtex-5 FPGA. Moving beyond verification with an onboard data source, the algorithm has been validated on a commercial development board interfaced with the ground camera. In addition, the algorithm has been instantiated within the Air-MSPI electronics board's FPGA, and in situ first-light has been achieved.
    Keywords: Instrumentation and Photography
    Type: IEEEAC Paper-1303 , IEEE Aerospace Conference; Mar 05, 2011 - Mar 12, 2011; Big Sky, MT; United States
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  • 9
    Publication Date: 2019-07-13
    Description: The Earth Sciences Decadal Survey identifies a multiangle, multispectral, high-accuracy polarization imager as one requirement for the Aerosol-Cloud-Ecosystem (ACE) mission. JPL has been developing a Multiangle SpectroPolarimetric Imager (MSPI) as a candidate to fill this need. A key technology development needed for MSPI is on-board signal processing to calculate polarimetry data as imaged by each of the 9 cameras forming the instrument. With funding from NASA's Advanced Information Systems Technology (AIST) Program, JPL is solving the real-time data processing requirements to demonstrate, for the first time, how signal data at 95 Mbytes/sec over 16-channels for each of the 9 multiangle cameras in the spaceborne instrument can be reduced on-board to 0.45 Mbytes/sec. This will produce the intensity and polarization data needed to characterize aerosol and cloud microphysical properties. Using the Xilinx Virtex-5 FPGA including PowerPC440 processors we have implemented a least squares fitting algorithm that extracts intensity and polarimetric parameters in real-time, thereby substantially reducing the image data volume for spacecraft downlink without loss of science information.
    Keywords: Instrumentation and Photography
    Type: ESTF 2010 (Earth Science Technology Forum); Jun 22, 2010; Arlington, VA; United States
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