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Recovery and Sequestration of CO2 From Stationary Combustion Systems by Photosynthesis of Microalgae, Quarterly Technical Report: January-March 2003

Description: Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarily at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report covers the reporting period 1 January to 31 March 2003 in which PSI, Aquasearch and University of Hawaii conducted their tasks. Based on the work during the previous reporting period, PSI conducted preparation work on direct feeding of coal combustion gas to microalgae and developed a design concept for photobioreactors for biofixation of CO{sub 2} and photovoltaic power generation. Aquasearch continued their effort on characterization of microalgae suitable for CO{sub 2} sequestration and preparation for pilot scale demonstration. University of Hawaii continued effort on system optimization of the CO{sub 2} sequestration system.
Date: May 2003
Creator: Nakamura, T.
Partner: UNT Libraries Government Documents Department

Recovery and Sequestration of CO2 From Stationary Combustion Systems by Photosynthesis of Microalgae, Quarterly Technical Report: October-December 2000

Description: Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarily at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report covers the reporting period from 1 October to 31 December 2000. During this period planning of chemostat experiments at Aquasearch was initiated. These experiments will be used to select microalgae for the photobioreactor demonstrations. An initial survey of techniques for removing CO{sub 2} from coal-fired flue gas was begun. Chemical adsorption using MEA is the most mature technology and looks to be the most economically viable in the near future.
Date: March 1, 2001
Creator: Nakamura, T. & Senior, C. L.
Partner: UNT Libraries Government Documents Department

Recovery and Sequestration of CO2 From Stationary Combustion Systems by Photosynthesis of Microalgae, Quarterly Technical Report: January-March 2001

Description: Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarily at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report covers the reporting period 1 January to 31 March 2001 in which Aquasearch tested 24 different species of microalgae for growth at three different temperatures. Eleven species were analyzed for the presence of high-value pigments. Most of the algae analyzed were good sources of industrially valuable pigments. Analysis of the methods for introducing and dissolving CO{sub 2} in the commercial bioreactor was begun this quarter.
Date: May 1, 2001
Creator: Nakamura, T. & Senior, C. L.
Partner: UNT Libraries Government Documents Department

Recovery and Sequestration of co2 From Stationary Combustion Systems by Photosynthesis of Microalgae, Quarterly Technical Progress Report: July-September 2002

Description: Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarily at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report covers the reporting period 1 July to 30 September 2002 in which PSI, Aquasearch and University of Hawaii conducted their tasks. Based on the work conducted during the previous reporting period, PSI initiated work on feasibility demonstration of direct feeding of coal combustion gas to microalgae. Aquasearch continued their effort on selection and characterization of microalgae suitable for CO{sub 2} sequestration. University of Hawaii continued effort on system optimization of the CO{sub 2} sequestration system.
Date: December 1, 2002
Creator: Nakamura, T.; Olaizola, Miguel & Masutani, Stephen M.
Partner: UNT Libraries Government Documents Department

Recovery and Sequestration of co2 From Stationary Combustion Systems by Photosynthesis of Microalgae, Quarterly Technical Progress Report: April-June 2002

Description: Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarily at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report covers the reporting period 1 April to 30 June 2002 in which PSI, Aquasearch and University of Hawaii conducted their tasks. Based on the work conducted during the previous reporting period, PSI initiated work on feasibility demonstration of direct feeding of coal combustion gas to microalgae. Aquasearch continued their effort on selection and characterization of microalgae suitable for CO{sub 2} sequestration. University of Hawaii continued effort on system optimization of the CO{sub 2} sequestration system.
Date: October 1, 2002
Creator: Nakamura, T.; Olaizola, Miguel & Masutani, Stephen M.
Partner: UNT Libraries Government Documents Department

Recovery and Sequestration of CO2 From Stationary Combustion Systems by Photosynthesis of Microalgae, Quarterly Technical Report: April-June 2001

Description: Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarily at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report covers the reporting period 1 April to 30 June 2001 in which PSI, Aquasearch and University of Hawaii conducted their tasks. Based on the work conducted during the previous reporting period, PSI initiated work on the component optimization work. Aquasearch continued their effort on selection of microalgae suitable for CO{sub 2} sequestration. University of Hawaii initiated effort on system optimization of the CO{sub 2} sequestration system.
Date: August 1, 2001
Creator: Nakamura, T.; Olaizola, Miguel & Masutani, Steven M.
Partner: UNT Libraries Government Documents Department

Recovery and Sequestration of CO2 from Stationary Combustion Systems by Photosynthesis of Microalgae: Final Report

Description: Most of the anthropogenic emissions of carbon dioxide result from the combustion of fossil fuels for energy production. Photosynthesis has long been recognized as a means, at least in theory, to sequester anthropogenic carbon dioxide. Aquatic microalgae have been identified as fast growing species whose carbon fixing rates are higher than those of land-based plants by one order of magnitude. Physical Sciences Inc. (PSI), Aquasearch, and the Hawaii Natural Energy Institute at the University of Hawaii are jointly developing technologies for recovery and sequestration of CO{sub 2} from stationary combustion systems by photosynthesis of microalgae. The research is aimed primarily at demonstrating the ability of selected species of microalgae to effectively fix carbon from typical power plant exhaust gases. This report covers the reporting period 1 October 2000 to 31 March 2005 in which PSI, Aquasearch and University of Hawaii conducted their tasks. This report discusses results of the work pertaining to five tasks: Task 1--Supply of CO2 from Power Plant Flue Gas to Photobioreactor; Task 2--Selection of Microalgae; Task 3--Optimization and Demonstration of Industrial Scale Photobioreactor; Task 4--Carbon Sequestration System Design; and Task 5--Economic Analysis. Based on the work conducted in each task summary conclusion is presented.
Date: April 1, 2005
Creator: Nakamura, T. & Senior, C. L.
Partner: UNT Libraries Government Documents Department

Correlation of recent fission product release data

Description: For the calculation of source terms associated with severe accidents, it is necessary to model the release of fission products from fuel as it heats and melts. Perhaps the most definitive model for fission product release is that of the FASTGRASS computer code developed at Argonne National Laboratory. There is persuasive evidence that these processes, as well as additional chemical and gas phase mass transport processes, are important in the release of fission products from fuel. Nevertheless, it has been found convenient to have simplified fission product release correlations that may not be as definitive as models like FASTGRASS but which attempt in some simple way to capture the essence of the mechanisms. One of the most widely used such correlation is called CORSOR-M which is the present fission product/aerosol release model used in the NRC Source Term Code Package. CORSOR has been criticized as having too much uncertainty in the calculated releases and as not accurately reproducing some experimental data. It is currently believed that these discrepancies between CORSOR and the more recent data have resulted because of the better time resolution of the more recent data compared to the data base that went into the CORSOR correlation. This document discusses a simple correlational model for use in connection with NUREG risk uncertainty exercises. 8 refs., 4 figs., 1 tab.
Date: January 1, 1989
Creator: Kress, T. S.; Lorenz, R. A.; Nakamura, T. & Osborne, M. F.
Partner: UNT Libraries Government Documents Department

Experimental techniques and measurement accuracies

Description: A brief description of the experimental tools available for fusion neutronics experiments is given. Attention is paid to error estimates mainly for the measurement of tritium breeding ratio in simulated blankets using various techniques.
Date: February 1985
Creator: Bennett, E.F.; Yule, T.J.; DiIorio, G.; Nakamura, T. & Maekawa, H.
Partner: UNT Libraries Government Documents Department

A preliminary comparison of beam instabilities among ESRF, APS, and spring-8 x-ray storage ring light sources.

Description: A collaboration has been established among the three highest energy storage ring synchrotron light sources: European Synchrotron Radiation Facility (ESRF) (6 GeV), Advanced Photon Source (APS) (7 GeV), and Super Photon Ring (SPring-8) (8 GeV). The goal is to enhance understanding of impedance and beam instability characteristics for present performance and future machine development. In this paper, we compare the beam instability characteristics of the three rings and present a preliminary discussion of the similarities and differences. Topics for future, in-depth study, such as comparing the effect on the beam of in-vacuum insertion devices (IDs) and small-gap chambers, will be described.
Date: June 13, 2002
Creator: Harkay, K.; Nagaoka, R.; Revol, J.-L. & Nakamura, T.
Partner: UNT Libraries Government Documents Department

Liquid helium dump concept for a large scale superconducting magnetic energy storage plant

Description: Superconducting Magnetic Energy Storage (SMES) is a potentially cost effective technology for electric utility load leveling. Design concepts and cost estimates of SMES plants capable of delivering 5000 MWh daily have been previously identified. An important feature of a large commercial plant is a system that will reliably shut down the magnet by thermally dissipating the stored energy in the event of an imminent or actual loss of superconductivity. To prevent damage to the coil during such a protective energy dump, the entire coil must be driven ''normal'', i.e., resistive rather than superconducting, in a short period of time. This requires rapid removal of the liquid helium coolant surrounding the coil. This paper describes a simple system that has been developed to rapidly remove the liquid helium from the helium vessel. The system requires only a small number of active components, no external helium storage, and is practical to reset and maintain.
Date: January 1, 1985
Creator: Schoenung, S. M.; Loyd, R. J.; Nakamura, T.; Rogers, J. D. & Purcell, J. R.
Partner: UNT Libraries Government Documents Department

High magnetic field MHD generator program. Final report, July 1, 1976-December 31, 1979

Description: A theoretical and experimental program was undertaken to investigate MHD channel phenomena which are important at high magnetic fields. The areas studied were inhomogeneity effects, boundary layers, Hall field breakdown and electrode configuration and current concentrations. In addition, a program was undertaken to study steady-state combustion disk and linear channels in an existing 6 Tesla magnet of small dimensions. The structure of the inhomogeneities in the Stanford M-2 was characterized and compared with theoretical results from a linearized perturbation analysis. General agreement was obtained and the analysis was used to compute stability regions for large size generators. The Faraday electrical connection was found to be more stable than the Hall or diagonal wall connections. Boundary layer profile measurements were compared with theoretical calculations with good agreement. Extrapolation of the calculations to pilot scale MHD channels indicates that Hartmann effects are important in the analysis of the sidewall, and Joule heating is important in calculating heat transfer and voltage drops for the electrode wall. Hall field breakdown was shown to occur both in the plasma and through the interelectrode insulator with the insulator breakdown threshold voltage lower than the plasma value. The threshold voltage was shown to depend on the interelectrode gap but was relatively independent of plasma conditions. Experiments were performed at 5.5 Tesla with both disk and linear MHD channels.
Date: April 1, 1980
Creator: Eustis, R. H.; Kruger, C. H.; Mitchner, M.; Self, S. A.; Koester, J. K. & Nakamura, T.
Partner: UNT Libraries Government Documents Department

Design and cost of a utility scale superconducting magnetic energy storage plant

Description: Superconducting Magnetic Energy Storage (SMES) has potential as a viable technology for use in electric utility load leveling. The advantage of SMES over other energy storage technologies is its high net roundtrip energy efficiency. This paper reports the major features and costs of a jointly developed 5000 MWh SMES plant design.
Date: January 1, 1985
Creator: Loyd, R. J.; Nakamura, T.; Schoenung, S. M.; Lieurance, D. W.; Hilal, M. A.; Rogers, J. D. et al.
Partner: UNT Libraries Government Documents Department

Feasible utility scale Superconducting Magnetic Energy Storage system

Description: This paper presents the latest design features and estimated costs of a 5000 MWh/1000 MW Superconducting Magnetic Energy Storage (SMES) plant. SMES is proposed as a commercially viable technology for electric utility load leveling. The primary advantage of SMES over other electrical energy storage technologies is its high net roundtrip efficiency. Other features include rapid availability and low maintenance and operating costs. Economic comparisons are made with other energy storage options and with gas turbines. In a diurnal load leveling application, a superconducting coil can be charged from the utility grid during off-peak hours. The ac grid is connected to the dc magnetic coil through a power conversion system that includes an inverter/rectifier. Once charged, the superconducting coil conducts current, which supports an electromagnetic field, with virtually no losses. During hours of peak load, the stored energy is discharged to the grid by reversing the charging process. The principle of operation of a SMES unit is shown in Fig. 1. For operation in the superconducting mode, the coil is maintained at extremely low temperature by immersion in a bath of liquid helium.
Date: January 1, 1986
Creator: Loyd, R. J.; Schoenung, S. M.; Nakamura, T.; Lieurance, D. W.; Hilal, M. A.; Rogers, J. D. et al.
Partner: UNT Libraries Government Documents Department

Overview of secondary neutron production relevant to shielding inspace

Description: An overview of experimental secondary neutron measurements relevant to space-related activities is presented. Stopping target yields and cross section measurements conducted at particle accelerators using heavy ions with energies >100 MeV per nucleon are discussed.
Date: December 3, 2004
Creator: Heilbronn, L.; Nakamura, T.; Iwata, Y.; Kurosawa, T.; Iwase, H. & Townsend, L.W.
Partner: UNT Libraries Government Documents Department

Commissioning of the Digital Transverse Bunch-by-Bunch Feedback System for the Tls.

Description: Multi-bunch instabilities degrade beam quality through increased beam emittance, energy spread and even beam loss. Feedback systems are used to suppress multi-bunch instabilities associated with the resistive wall of the beam ducts, cavity-like structures, and trapped ions. A new digital transverse bunch-by-bunch feedback system has recently been commissioned at the Taiwan Light Source, and has replaced the previous analog system. The new system has the advantages that it enlarges the tune acceptance and improves damping for transverse instability at high currents, such that top-up operation is achieved. After a coupled-bunch transverse instability was suppressed, more than 350 mA was successfully stored during preliminary commissioning. In this new system, a single feedback loop simultaneously suppresses both horizontal and vertical multi-bunch instabilities. Investigating the characteristics of the feedback loop and further improving the system performances are the next short-term goals. The feedback system employs the latest generation of field-programmable gate array (FPGA) processor to process bunch signals. Memory has been installed to capture up to 250 msec of bunch oscillation signal, considering system diagnostics suitable to support various beam physics studies.
Date: June 26, 2006
Creator: Hu, K. H.; Kuo, C. H.; Chou, P. J.; Lee, D.; Hsu, S. Y.; Chen, J. et al.
Partner: UNT Libraries Government Documents Department

Secondary neutron-production cross sections from heavy-ioninteractions in composite targets.

Description: Secondary neutron-production cross-sections have been measured from interactions of 290 MeV/nucleon C and 600 MeV/nucleon Ne in a target composed of simulated Martian regolith and polyethylene, and from 400 MeV/nucleon Ne interactions in wall material from the International Space Station. The data were measured between 5 and 80 deg in the laboratory. We report the double-differential cross sections, angular distributions, and total neutron-production cross sections from all three systems. The spectra from all three systems exhibit behavior previously reported in other heavy-ion, neutron production experiments; namely, a peak at forward angles near the energy corresponding to the beam velocity, with the remaining spectra generated by pre-equilibrium and equilibrium processes. The double differential cross sections are fitted with a moving-source parameterization. Also reported are the data without corrections for neutron flux attenuation in the target and other intervening materials, and for neutron production in non-target materials near the target position. These uncorrected spectra are compared with SHIELD-HIT and PHITS transport model calculations. The transport model calculations reproduce the spectral shapes well, but, on average, underestimate the magnitudes of the cross sections.
Date: December 19, 2005
Creator: Heilbronn, L.; Iwata, Y.; Iwase,H.; Murakami, T.; Sato, H.; Nakamura, T. et al.
Partner: UNT Libraries Government Documents Department

Measurements of Total and Partial Charge-changing Cross Sections for 200-400 MeV/nucleon 12C in Water and Polycarbonate

Description: We have studied charged nuclear fragments produced by 200 - 400 MeV/nucleon carbon ions, interacting with water and polycarbonate, using a newly developed emulsion detector. Total and partial charge-changing cross sections for the production of B, Be, and Li fragments were measured and compared with both previously published measurements, and model predictions. This study is of importance for validating and improving carbon ion therapy treatment planning systems, and for estimating the radiological risks for personnel on space missions, since carbon is a significant component of the Galactic Cosmic Rays.
Date: November 10, 2011
Creator: Toshito, T.; Kodama, K.; Sihver, L.; Yusa, K.; Ozaki, M.; Amako, K. et al.
Partner: UNT Libraries Government Documents Department

Secondary Neutron-Production Cross Sections from Heavy-IonInteractions between 230 and 600 MeV/nucleon

Description: Secondary neutron-production cross-sections have beenmeasured from interactions of 230 MeV/nucleon He, 400 MeV/nucleon N, 400MeV/nucleon Kr, 400 MeV/nucleon Xe, 500 MeV/nucleon Fe, and 600MeV/nucleon Ne interacting in a variety of elemental and compositetargets. We report the double-differential production cross sections,angular distributions, energy spectra, and total cross sections from allsystems. Neutron energies were measured using the time-of-flighttechnique, and were measured at laboratory angles between 5 deg and 80deg. The spectra exhibit behavior previously reported in otherheavy-ion-induced neutron production experiments; namely, a peak atforward angles near the energy corresponding to the beam velocity, withthe remaining spectra generated by preequilibrium and equilibriumprocesses. The double-differential spectra are fitted with amoving-source parameterization. Observations on the dependence of thetotal cross sections on target and projectile mass arediscussed.
Date: October 4, 2006
Creator: Heilbronn, L.H.; Zeitlin, C.J.; Iwata, Y.; Murakami, T.; Iwase,H.; Nakamura, T. et al.
Partner: UNT Libraries Government Documents Department

Charge Identification of Highly Ionizing Particles in Desensitized Nuclear Emulsion Using High Speed Read-Out System

Description: We performed an experimental study of charge identification of heavy ions from helium to carbon having energy of about 290 MeV/u using an emulsion chamber. Emulsion was desensitized by means of forced fading (refreshing) to expand a dynamic range of response to highly charged particles. For the track reconstruction and charge identification, the fully automated high speed emulsion read-out system, which was originally developed for identifying minimum ionizing particles, was used without any modification. Clear track by track charge identification up to Z=6 was demonstrated. The refreshing technique has proved to be a powerful technique to expand response of emulsion film to highly ionizing particles.
Date: May 10, 2006
Creator: Toshito, T.; Kodama, K.; Yusa, K.; Ozaki, M.; Amako, K.; Kameoka, S. et al.
Partner: UNT Libraries Government Documents Department

Mineralogy and Petrology of Comet Wild 2 Nucleus Samples

Description: The bulk of the Wild 2 samples appear to be weakly-constructed mixtures of nanometerscale grains with occasional much larger (>1{micro}m) ferromagnesian silicates, Fe-Ni sulfides, Fe-Ni metal and accessory phases. The very wide range of olivine and low-Ca pyroxene compositions in Wild 2 require a wide range of formation conditions, probably reflecting different formation locations in the protoplanetary disk. The restricted compositional ranges of Fe-Ni sulfides, the wide range for silicates, and absence of hydrous phases indicate that Wild 2 experienced little or no aqueous alteration. Less abundant Wild 2 materials include a refractory particle, whose presence appears to require large-scale radial transport in the early protoplanetary disk. The nature of cometary solids is of fundamental importance to our understanding of the early solar nebula and protoplanetary history. Until now we have had to study comets from afar using spectroscopy, or settle for analyses of interplanetary dust particles (IDPs) of uncertain provenance. We report here mineralogical and petrographic analyses of particles derived directly from Comet Wild 2. All of the Wild 2 particles we have thus far examined have been modified in various ways by the capture process. All particles that may have been loose aggregates, ''traveling sand piles'', disaggregated into individual components with the larger, denser components penetrating more deeply into the aerogel. Individual grains experienced a wide range of heating effects that range from excellent preservation to melting (Fig. 1); such behavior was expected (1, 2 ,3). What is remarkable is the extreme variability of these modifications and the fact that severely modified and unmodified materials can be found within a micrometer of each other, requiring tremendous local temperature gradients. Fortunately, we have an internal gauge of impact collection heating. Fe-Ni sulfides are ubiquitous in the Wild 2 samples, are very sensitive indicators of heating, and accurate chemical analyses …
Date: October 11, 2006
Creator: Zolensky, M. E.; Zega, T. J.; Yano, H.; Wirick, S.; Westphal, A. J.; Weisberg, M. K. et al.
Partner: UNT Libraries Government Documents Department

Comet 81P/Wild 2 under a microscope

Description: The Stardust spacecraft collected thousands of particles from comet 81P/Wild 2 and returned them to Earth for laboratory study. The preliminary examination of these samples shows that the nonvolatile portion of the comet is an unequilibrated assortment of materials that have both presolar and solar system origin. The comet contains an abundance of silicate grains that are much larger than predictions of interstellar grain models, and many of these are high-temperature minerals that appear to have formed in the inner regions of the solar nebula. Their presence in a comet proves that the formation of the solar system included mixing on the grandest scales. Stardust was the first mission to return solid samples from a specific astronomical body other than the Moon. The mission, part of the NASA Discovery program, retrieved samples from a comet that is believed to have formed at the outer fringe of the solar nebula, just beyond the most distant planet. The samples, isolated from the planetary region of the solar system for billions of years, provide new insight into the formation of the solar system. The samples provide unprecedented opportunities both to corroborate astronomical (remote sensing) and sample analysis information (ground truth) on a known primitive solar system body and to compare preserved building blocks from the edge of the planetary system with sample-derived and astronomical data for asteroids, small bodies that formed more than an order of magnitude closer to the Sun. The asteroids, parents of most meteorites, formed by accretion of solids in warmer, denser, more collisionally evolved inner regions of the solar nebula where violent nebular events were capable of flash-melting millimeter-sized rocks, whereas comets formed in the coldest, least dense region. The samples collected by Stardust are the first primitive materials from a known body, and as such they provide contextual …
Date: October 12, 2006
Creator: Brownlee, D; Tsou, P.; Aleon, J.; Alexander, C.; Araki, T.; Bajt, S. et al.
Partner: UNT Libraries Government Documents Department
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