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Sample records for space environment electron

  1. The space radiation environment for electronics

    SciTech Connect

    Stassinopoulos, E.G.; Raymond, J.P.

    1988-11-01

    The earth's space radiation environment is described in terms of charged particles as relevant to effects on spacecraft electronics. The nature and magnitude of the trapped and transiting environments are described in terms of spatial distribution and temporal variation. The internal radiation environment of the spacecraft is described in terms of shielding the high-energy particles of the free-field environment. Exposure levels are presented in terms of ionizing radiation dose and particle fluence for comparison to electronic component susceptibility.

  2. Radiation Hardened Electronics for Space Environments (RHESE)

    NASA Technical Reports Server (NTRS)

    Keys, Andrew S.; Adams, James H.; Frazier, Donald O.; Patrick, Marshall C.; Watson, Michael D.; Johnson, Michael A.; Cressler, John D.; Kolawa, Elizabeth A.

    2007-01-01

    Radiation Environmental Modeling is crucial to proper predictive modeling and electronic response to the radiation environment. When compared to on-orbit data, CREME96 has been shown to be inaccurate in predicting the radiation environment. The NEDD bases much of its radiation environment data on CREME96 output. Close coordination and partnership with DoD radiation-hardened efforts will result in leveraged - not duplicated or independently developed - technology capabilities of: a) Radiation-hardened, reconfigurable FPGA-based electronics; and b) High Performance Processors (NOT duplication or independent development).

  3. The Near-Earth Space Radiation for Electronics Environment

    NASA Technical Reports Server (NTRS)

    Stassinopoulos, E. G.; LaBel, K. A.

    2004-01-01

    The earth's space radiation environment is described in terms of: a) charged particles as relevant to effects on spacecraft electronics, b) the nature and distribution of trapped and transiting radiation, and c) their effect on electronic components.

  4. Electron Beam Freeform Fabrication in the Space Environment

    NASA Technical Reports Server (NTRS)

    Hafley, Robert A.; Taminger, Karen M. B.; Bird, R. Keith

    2007-01-01

    The influence of reduced gravitational forces (in space and on the lunar or Martian surfaces) on manufacturing processes must be understood for effective fabrication and repair of structures and replacement parts during long duration space missions. The electron beam freeform fabrication (EBF3) process uses an electron beam and wire to fabricate metallic structures. The process efficiencies of the electron beam and the solid wire feedstock make the EBF3 process attractive for use in-space. This paper will describe the suitability of the EBF3 process in the space environment and will highlight preliminary testing of the EBF3 process in a zero-gravity environment.

  5. Radiation-Hardened Electronics for Space Environments (RHESE)

    NASA Technical Reports Server (NTRS)

    Keys, Andrew S.; Adams, James H.; Patrick, Marshall C.; Johnson, Michael; Cressler, John D.

    2008-01-01

    This conference poster explores NASA's Radiation-Hardened Electronics for Space Environments project. This project aims to advance the state of the art in high performance, radiation-hardened electronics that enable the long-term, reliable operation of a spacecraft in extreme radiation and temperature of space and the lunar surface.

  6. High-Performance, Radiation-Hardened Electronics for Space Environments

    NASA Technical Reports Server (NTRS)

    Keys, Andrew S.; Watson, Michael D.; Frazier, Donald O.; Adams, James H.; Johnson, Michael A.; Kolawa, Elizabeth A.

    2007-01-01

    The Radiation Hardened Electronics for Space Environments (RHESE) project endeavors to advance the current state-of-the-art in high-performance, radiation-hardened electronics and processors, ensuring successful performance of space systems required to operate within extreme radiation and temperature environments. Because RHESE is a project within the Exploration Technology Development Program (ETDP), RHESE's primary customers will be the human and robotic missions being developed by NASA's Exploration Systems Mission Directorate (ESMD) in partial fulfillment of the Vision for Space Exploration. Benefits are also anticipated for NASA's science missions to planetary and deep-space destinations. As a technology development effort, RHESE provides a broad-scoped, full spectrum of approaches to environmentally harden space electronics, including new materials, advanced design processes, reconfigurable hardware techniques, and software modeling of the radiation environment. The RHESE sub-project tasks are: SelfReconfigurable Electronics for Extreme Environments, Radiation Effects Predictive Modeling, Radiation Hardened Memory, Single Event Effects (SEE) Immune Reconfigurable Field Programmable Gate Array (FPGA) (SIRF), Radiation Hardening by Software, Radiation Hardened High Performance Processors (HPP), Reconfigurable Computing, Low Temperature Tolerant MEMS by Design, and Silicon-Germanium (SiGe) Integrated Electronics for Extreme Environments. These nine sub-project tasks are managed by technical leads as located across five different NASA field centers, including Ames Research Center, Goddard Space Flight Center, the Jet Propulsion Laboratory, Langley Research Center, and Marshall Space Flight Center. The overall RHESE integrated project management responsibility resides with NASA's Marshall Space Flight Center (MSFC). Initial technology development emphasis within RHESE focuses on the hardening of Field Programmable Gate Arrays (FPGA)s and Field Programmable Analog

  7. A Deterministic Computational Procedure for Space Environment Electron Transport

    NASA Technical Reports Server (NTRS)

    Nealy, John E.; Chang, C. K.; Norman, Ryan B.; Blattnig, Steve R.; Badavi, Francis F.; Adamcyk, Anne M.

    2010-01-01

    A deterministic computational procedure for describing the transport of electrons in condensed media is formulated to simulate the effects and exposures from spectral distributions typical of electrons trapped in planetary magnetic fields. The primary purpose for developing the procedure is to provide a means of rapidly performing numerous repetitive transport calculations essential for electron radiation exposure assessments for complex space structures. The present code utilizes well-established theoretical representations to describe the relevant interactions and transport processes. A combined mean free path and average trajectory approach is used in the transport formalism. For typical space environment spectra, several favorable comparisons with Monte Carlo calculations are made which have indicated that accuracy is not compromised at the expense of the computational speed.

  8. Technology Developments in Radiation-Hardened Electronics for Space Environments

    NASA Technical Reports Server (NTRS)

    Keys, Andrew S.; Howell, Joe T.

    2008-01-01

    The Radiation Hardened Electronics for Space Environments (RHESE) project consists of a series of tasks designed to develop and mature a broad spectrum of radiation hardened and low temperature electronics technologies. Three approaches are being taken to address radiation hardening: improved material hardness, design techniques to improve radiation tolerance, and software methods to improve radiation tolerance. Within these approaches various technology products are being addressed including Field Programmable Gate Arrays (FPGA), Field Programmable Analog Arrays (FPAA), MEMS, Serial Processors, Reconfigurable Processors, and Parallel Processors. In addition to radiation hardening, low temperature extremes are addressed with a focus on material and design approaches. System level applications for the RHESE technology products are discussed.

  9. A Deterministic Transport Code for Space Environment Electrons

    NASA Technical Reports Server (NTRS)

    Nealy, John E.; Chang, C. K.; Norman, Ryan B.; Blattnig, Steve R.; Badavi, Francis F.; Adamczyk, Anne M.

    2010-01-01

    A deterministic computational procedure has been developed to describe transport of space environment electrons in various shield media. This code is an upgrade and extension of an earlier electron code. Whereas the former code was formulated on the basis of parametric functions derived from limited laboratory data, the present code utilizes well established theoretical representations to describe the relevant interactions and transport processes. The shield material specification has been made more general, as have the pertinent cross sections. A combined mean free path and average trajectory approach has been used in the transport formalism. Comparisons with Monte Carlo calculations are presented.

  10. Radiation-Hardened Electronics for the Space Environment

    NASA Technical Reports Server (NTRS)

    Keys, Andrew S.; Watson, Michael D.

    2007-01-01

    RHESE covers a broad range of technology areas and products. - Radiation Hardened Electronics - High Performance Processing - Reconfigurable Computing - Radiation Environmental Effects Modeling - Low Temperature Radiation Hardened Electronics. RHESE has aligned with currently defined customer needs. RHESE is leveraging/advancing SOA space electronics, not duplicating. - Awareness of radiation-related activities through out government and industry allow advancement rather than duplication of capabilities.

  11. The Space Radiation Environment and Its Implication for Designing Reliable Electronic Systems: A NASA Perspective

    NASA Technical Reports Server (NTRS)

    LaBel, Kenneth A.

    2004-01-01

    The contents include the following: The space radiation environment. The effects on electronics. The environment in action NASA approaches to commercial electronics: flight projects; and proactive research. Living with a star space environment testbed status. Final thoughts: atomic interactions; direct ionization; interaction with nucleus.

  12. Thermal contact electronic packaging in solar pointing space environment

    SciTech Connect

    Colangelo, A.M. ); McKim, G.S. . Space Systems Div.)

    1991-02-01

    A thermal design for a solar pointing space shuttle mission is presented. The apparatus, which will measure solar flux intensity variations, contains sensors and data acquisition electronics which must be maintained within certain temperature constraints. The thermal design, which utilizes parallel heat flow paths and conduction fins to reject dissipated heat, is shown by finite difference thermal modeling to maintain component temperatures within these constraints. In the thermal modeling, arithmetic nodes are used to represent surface radiosity for radiation heat transfer. Also, the concept of mean fin conduction length and effective fin capacitance are introduced as means of simplifying the model representation of the conduction fins. An experiment was conducted to evaluate the chip/fin contact conductance.

  13. Spacecraft Environments Interactive: Space Radiation and Its Effects on Electronic System

    NASA Technical Reports Server (NTRS)

    Howard, J. W., Jr.; Hardage, D. M.

    1999-01-01

    The natural space environment is characterized by complex and subtle phenomena hostile to spacecraft. Effects of these phenomena impact spacecraft design, development, and operation. Space systems become increasingly susceptible to the space environment as use of composite materials and smaller, faster electronics increases. This trend makes an understanding of space radiation and its effects on electronic systems essential to accomplish overall mission objectives, especially in the current climate of smaller/better/cheaper faster. This primer outlines the radiation environments encountered in space, discusses regions and types of radiation, applies the information to effects that these environments have on electronic systems, addresses design guidelines and system reliability, and stresses the importance of early involvement of radiation specialists in mission planning, system design, and design review (part-by-part verification).

  14. High-Performance, Radiation-Hardened Electronics for Space and Lunar Environments

    NASA Technical Reports Server (NTRS)

    Keys, Andrew S.; Adams, James H.; Cressler, John D.; Darty, Ronald C.; Johnson, Michael A.; Patrick, Marshall C.

    2008-01-01

    The Radiation Hardened Electronics for Space Environments (RHESE) project develops advanced technologies needed for high performance electronic devices that will be capable of operating within the demanding radiation and thermal extremes of the space, lunar, and Martian environment. The technologies developed under this project enhance and enable avionics within multiple mission elements of NASA's Vision for Space Exploration. including the Constellation program's Orion Crew Exploration Vehicle. the Lunar Lander project, Lunar Outpost elements, and Extra Vehicular Activity (EVA) elements. This paper provides an overview of the RHESE project and its multiple task tasks, their technical approaches, and their targeted benefits as applied to NASA missions.

  15. High-Performance, Radiation-Hardened Electronics for Space and Lunar Environments

    NASA Astrophysics Data System (ADS)

    Keys, Andrew S.; Adams, James H.; Cressler, John D.; Darty, Ronald C.; Johnson, Michael A.; Patrick, Marshall C.

    2008-01-01

    The Radiation Hardened Electronics for Space Environments (RHESE) project develops advanced technologies needed for high performance electronic devices that will be capable of operating within the demanding radiation and thermal extremes of the space, lunar, and Martian environment. The technologies developed under this project enhance and enable avionics within multiple mission elements of NASA's Vision for Space Exploration, including the Constellation program's Orion Crew Exploration Vehicle, the Lunar Lander project, Lunar Outpost elements, and Extra Vehicular Activity (EVA) elements. This paper provides an overview of the RHESE project and its multiple task tasks, their technical approaches, and their targeted benefits as applied to NASA missions.

  16. The Space Radiation Environment as it Relates to Electronic System Performance: Or Why Not to Fly Commercial Electronic Components in Space

    NASA Technical Reports Server (NTRS)

    Barth, Janet L.; Xapsos, Michael A.; LaBel, Kenneth A.; Polvey, Christian

    2005-01-01

    This viewgraph presentation offers an overview of the space radiation environment, primarily in near-Earth environments such as Low Earth Orbit (LEO). The presentation describes the Halloween solar event of 2003 as an example of how solar activity can affect spacecraft electronic systems. The lunar radiation environment is also briefly summarized.

  17. Exploration Technology Developments Program's Radiation Hardened Electronics for Space Environments (RHESE) Project Overview

    NASA Technical Reports Server (NTRS)

    Keys, Andrew S.; Adams, James H.; Darty, Ronald C.; Patrick, Marshall C.; Johnson, Michael A.; Cressler, John D.

    2008-01-01

    Primary Objective: 1) A computational tool to accurately predict electronics performance in the presence of space radiation in support of spacecraft design: a) Total dose; b) Single Event Effects; and c) Mean Time Between Failure. (Developed as successor to CR ME96.) Secondary Objectives: 2) To provide a detailed description of the natural radiation environment in support of radiation health and instrument design: a) In deep space; b) Inside the magnetosphere; and c) Behind shielding.

  18. High Performance Processors for Space Environments: A Subproject of the NASA Exploration Missions Systems Directorate "Radiation Hardened Electronics for Space Environments" Technology Development Program

    NASA Technical Reports Server (NTRS)

    Johnson, M.; Label, K.; McCabe, J.; Powell, W.; Bolotin, G.; Kolawa, E.; Ng, T.; Hyde, D.

    2007-01-01

    Implementation of challenging Exploration Systems Missions Directorate objectives and strategies can be constrained by onboard computing capabilities and power efficiencies. The Radiation Hardened Electronics for Space Environments (RHESE) High Performance Processors for Space Environments project will address this challenge by significantly advancing the sustained throughput and processing efficiency of high-per$ormance radiation-hardened processors, targeting delivery of products by the end of FY12.

  19. Transport of Space Environment Electrons: A Simplified Rapid-Analysis Computational Procedure

    NASA Technical Reports Server (NTRS)

    Nealy, John E.; Anderson, Brooke M.; Cucinotta, Francis A.; Wilson, John W.; Katz, Robert; Chang, C. K.

    2002-01-01

    A computational procedure for describing transport of electrons in condensed media has been formulated for application to effects and exposures from spectral distributions typical of electrons trapped in planetary magnetic fields. The procedure is based on earlier parameterizations established from numerous electron beam experiments. New parameterizations have been derived that logically extend the domain of application to low molecular weight (high hydrogen content) materials and higher energies (approximately 50 MeV). The production and transport of high energy photons (bremsstrahlung) generated in the electron transport processes have also been modeled using tabulated values of photon production cross sections. A primary purpose for developing the procedure has been to provide a means for rapidly performing numerous repetitive calculations essential for electron radiation exposure assessments for complex space structures. Several favorable comparisons have been made with previous calculations for typical space environment spectra, which have indicated that accuracy has not been substantially compromised at the expense of computational speed.

  20. Lunar Dust Grain Charging by Electron Impact: Complex Role of Secondary Electron Emissions in Space Environments

    NASA Astrophysics Data System (ADS)

    Abbas, M. M.; Tankosic, D.; Craven, P. D.; LeClair, A. C.; Spann, J. F.

    2010-08-01

    Dust grains in various astrophysical environments are generally charged electrostatically by photoelectric emissions with radiation from nearby sources, or by electron/ion collisions by sticking or secondary electron emissions (SEEs). The high vacuum environment on the lunar surface leads to some unusual physical and dynamical phenomena involving dust grains with high adhesive characteristics, and levitation and transportation over long distances. Knowledge of the dust grain charges and equilibrium potentials is important for understanding a variety of physical and dynamical processes in the interstellar medium, and heliospheric, interplanetary/planetary, and lunar environments. It has been well recognized that the charging properties of individual micron-/submicron-size dust grains are expected to be substantially different from the corresponding values for bulk materials. In this paper, we present experimental results on the charging of individual 0.2-13 μm size dust grains selected from Apollo 11 and 17 dust samples, and spherical silica particles by exposing them to mono-energetic electron beams in the 10-200 eV energy range. The dust charging process by electron impact involving the SEEs discussed is found to be a complex charging phenomenon with strong particle size dependence. The measurements indicate substantial differences between the polarity and magnitude of the dust charging rates of individual small-size dust grains, and the measurements and model properties of corresponding bulk materials. A more comprehensive plan of measurements of the charging properties of individual dust grains for developing a database for realistic models of dust charging in astrophysical and lunar environments is in progress.

  1. LUNAR DUST GRAIN CHARGING BY ELECTRON IMPACT: COMPLEX ROLE OF SECONDARY ELECTRON EMISSIONS IN SPACE ENVIRONMENTS

    SciTech Connect

    Abbas, M. M.; Craven, P. D.; LeClair, A. C.; Spann, J. F.; Tankosic, D.

    2010-08-01

    Dust grains in various astrophysical environments are generally charged electrostatically by photoelectric emissions with radiation from nearby sources, or by electron/ion collisions by sticking or secondary electron emissions (SEEs). The high vacuum environment on the lunar surface leads to some unusual physical and dynamical phenomena involving dust grains with high adhesive characteristics, and levitation and transportation over long distances. Knowledge of the dust grain charges and equilibrium potentials is important for understanding a variety of physical and dynamical processes in the interstellar medium, and heliospheric, interplanetary/planetary, and lunar environments. It has been well recognized that the charging properties of individual micron-/submicron-size dust grains are expected to be substantially different from the corresponding values for bulk materials. In this paper, we present experimental results on the charging of individual 0.2-13 {mu}m size dust grains selected from Apollo 11 and 17 dust samples, and spherical silica particles by exposing them to mono-energetic electron beams in the 10-200 eV energy range. The dust charging process by electron impact involving the SEEs discussed is found to be a complex charging phenomenon with strong particle size dependence. The measurements indicate substantial differences between the polarity and magnitude of the dust charging rates of individual small-size dust grains, and the measurements and model properties of corresponding bulk materials. A more comprehensive plan of measurements of the charging properties of individual dust grains for developing a database for realistic models of dust charging in astrophysical and lunar environments is in progress.

  2. Lunary Dust Grain Charging by Electron Impact: Complex Role of Secondary Electron Emissions in Space Environments

    NASA Technical Reports Server (NTRS)

    Abbas, M. M.; Tankosic, D.; Crave, P. D.; LeClair, A.; Spann, J. F.

    2010-01-01

    Dust grains in various astrophysical environments are generally charged electrostatically by photoelectric emissions with radiation from nearby sources, or by electron/ion collisions by sticking or secondary electron emissions (SEES). The high vacuum environment on the lunar surface leads to some unusual physical and dynamical phenomena involving dust grains with high adhesive characteristics, and levitation and transportation over long distances. Knowledge of the dust grain charges and equilibrium potentials is important for understanding a variety of physical and dynamical processes in the interstellar medium, and heliospheric, interplanetary/ planetary, and lunar environments. It has been well recognized that the charging properties of individual micron-/submicron-size dust grains are expected to be substantially different from the corresponding values for bulk materials. In this paper, we present experimental results on the charging of individual 0.2-13 m size dust grains selected from Apollo 11 and 17 dust samples, and spherical silica particles by exposing them to mono-energetic electron beams in the 10-200 eV energy range. The dust charging process by electron impact involving the SEES discussed is found to be a complex charging phenomenon with strong particle size dependence. The measurements indicate substantial differences between the polarity and magnitude of the dust charging rates of individual small-size dust grains, and the measurements and model properties of corresponding bulk materials. A more comprehensive plan of measurements of the charging properties of individual dust grains for developing a database for realistic models of dust charging in astrophysical and lunar environments is in progress.

  3. Microsystems, Space Qualified Electronics and Mobile Sensor Platforms for Harsh Environment Applications and Planetary Exploration

    NASA Technical Reports Server (NTRS)

    Hunter, Gary W.; Okojie, Robert S.; Krasowski, Michael J.; Beheim, Glenn M.; Fralick, Gustave C.; Wrbanek, John D.; Greenberg, Paul S.; Xu, Jennifer

    2007-01-01

    NASA Glenn Research Center is presently developing and applying a range of sensor and electronic technologies that can enable future planetary missions. These include space qualified instruments and electronics, high temperature sensors for Venus missions, mobile sensor platforms, and Microsystems for detection of a range of chemical species and particulates. A discussion of each technology area and its level of maturity is given. It is concluded that there is a strong need for low power devices which can be mobile and provide substantial characterization of the planetary environment where and when needed. While a given mission will require tailoring of the technology for the application, basic tools which can enable new planetary missions are being developed.

  4. A Review of NASA's Radiation-Hardened Electronics for Space Environments Project

    NASA Technical Reports Server (NTRS)

    Keys, Andrew S.; Adams, James H.; Patrick, Marshall C.; Johnson, Michael A.; Cressler, John D.

    2008-01-01

    NASA's Radiation Hardened Electronics for Space Exploration (RHESE) project develops the advanced technologies required to produce radiation hardened electronics, processors, and devices in support of the requirements of NASA's Constellation program. Over the past year, multiple advancements have been made within each of the RHESE technology development tasks that will facilitate the success of the Constellation program elements. This paper provides a brief review of these advancements, discusses their application to Constellation projects, and addresses the plans for the coming year.

  5. Electronics for Extreme Environments

    NASA Astrophysics Data System (ADS)

    Patel, J. U.; Cressler, J.; Li, Y.; Niu, G.

    2001-01-01

    Most of the NASA missions involve extreme environments comprising radiation and low or high temperatures. Current practice of providing friendly ambient operating environment to electronics costs considerable power and mass (for shielding). Immediate missions such as the Europa orbiter and lander and Mars landers require the electronics to perform reliably in extreme conditions during the most critical part of the mission. Some other missions planned in the future also involve substantial surface activity in terms of measurements, sample collection, penetration through ice and crust and the analysis of samples. Thus it is extremely critical to develop electronics that could reliably operate under extreme space environments. Silicon On Insulator (SOI) technology is an extremely attractive candidate for NASA's future low power and high speed electronic systems because it offers increased transconductance, decreased sub-threshold slope, reduced short channel effects, elimination of kink effect, enhanced low field mobility, and immunity from radiation induced latch-up. A common belief that semiconductor devices function better at low temperatures is generally true for bulk devices but it does not hold true for deep sub-micron SOI CMOS devices with microscopic device features of 0.25 micrometers and smaller. Various temperature sensitive device parameters and device characteristics have recently been reported in the literature. Behavior of state of the art technology devices under such conditions needs to be evaluated in order to determine possible modifications in the device design for better performance and survivability under extreme environments. Here, we present a unique approach of developing electronics for extreme environments to benefit future NASA missions as described above. This will also benefit other long transit/life time missions such as the solar sail and planetary outposts in which electronics is out open in the unshielded space at the ambient space

  6. Lessons Learned Using COTS Electronics for the International Space Station Radiation Environment

    NASA Technical Reports Server (NTRS)

    Blumer, John H.; Roth, A. (Technical Monitor)

    2001-01-01

    The mantra of 'Faster, Better, Cheaper' has to a large degree been interpreted as using Commercial Off-the-Shelf (COTS) components and/or circuit boards. One of the first space applications to actually use COTS in space along with radiation performance requirements was the Expedite the Processing of Experiments to Space Station (EXPRESS) Rack program, for the International Space Station (ISS). In order to meet the performance, cost and schedule targets, military grade Versa Module Eurocard (VME) was selected as the baseline design for the main computer, the Rack Interface Controller (RIC). VME was chosen as the computer backplane because of the large variety of military grade boards available, which were designed to meet the military environmental specifications (thermal, shock, vibration, etc.). These boards also have a paper pedigree in regards to components. Since these boards exceeded most ISS environmental requirements, it was reasoned using COTS mid-grade VME boards, as opposed to designing custom boards could save significant time and money. It was recognized up front the radiation environment of ISS, while benign compared to many space flight applications, would be the main challenge to using COTS. Thus in addition to selecting vendors on how well their boards met the usual performance and environmental specifications, the board's parts lists were reviewed on how well they would perform in the ISS radiation environment. However, issues with verifying that the available radiation test data was applicable to the actual part used, vendor part design changes and the fact most parts did not have valid test data soon complicated board and part selection in regards to radiation.

  7. Lessons learned using COTS electronics for the International Space Station radiation environment

    NASA Astrophysics Data System (ADS)

    Blumer, John H.

    2001-02-01

    The mantra of Faster, Better, Cheaper has to a large degree been interpreted as using Commercial Off The Shelf (COTS) components and/or circuit boards. One of the first space applications to actually use COTS in space along with radiation performance requirements was the EXpedite the PRocessing of Experiments to Space Station (EXPRESS) Rack program, for the International Space Station (ISS). In order to meet the performance, cost and schedule targets, military grade Versa Module Eurocard (VME) was selected as the baseline design for the main computer, the Rack Interface Controller (RIC). VME was chosen as the computer backplane because of the large variety of military grade boards available, which were designed to meet the military environmental specifications (thermal, shock, vibration, etc.). These boards also have a paper pedigree in regards to components. Since these boards exceeded most ISS environmental requirements, it was reasoned using COTS mil-grade VME boards, as opposed to designing custom boards could save significant time and money. It was recognized up front the radiation environment of ISS, while benign compared to many space flight applications, would be the main challenge to using COTS. Thus in addition to selecting vendors on how well their boards met the usual performance and environmental specifications, the board's parts lists were reviewed on how well they would perform in the ISS radiation environment. However, issues with verifying that the available radiation test data was applicable to the actual part used, vendor part design changes and the fact most parts did not have valid test data soon complicated board and part selection in regards to radiation. .

  8. Materials selection for electronic enclosures in space environment considering electromagnetic interference effect

    NASA Astrophysics Data System (ADS)

    Fayazbakhsh, K.; Abedian, A.

    2012-02-01

    Using low power electronic devices for space applications to reduce the mass and energy consumption has lead to electromagnetic interference (EMI) problem. Electronic enclosures are used to shield electronic devices against EMI. In the past, electromagnetic shielding has been mainly the only criteria considered in electronic enclosure design. However, there are several structural and thermal requirements for selection of shielding materials which should also be taken into account. In this research work, three quantitative materials selection methods, i.e. Digital Logic (DL), Modified Digital Logic (MDL), and Z-transformation, are employed to select the best material from among a list of candidate materials. Composite and metallic electronic enclosures are explored and the best material is selected. Z-transformation method is applicable to both of the considered case studies while DL and MDL can only be used for solving one of them. Z-transformation method ranks aluminum as the first choice among various metallic materials. The wide range of Z-transformation application and its practical results confirm the superiority of Z-transformation method over DL and MDL methods.

  9. Space and Atmospheric Environments

    NASA Technical Reports Server (NTRS)

    Barth, Janet L.; Day, John H. (Technical Monitor)

    2002-01-01

    This viewgraph presentation provides information on space environments and the protection of materials and structures from their harsh conditions. Space environments are complex, and the complexity of spacecraft systems is increasing. Design accommodation must be realistic. Environmental problems can be limited at low cost relative to spacecraft cost.

  10. Complex influence of space environment on materials and electronic devices in the conditions of microgravity

    NASA Astrophysics Data System (ADS)

    Musabayev, T.; Zhantayev, Zh.; Grichshenko, V.

    2016-09-01

    The paper presents a new physical model describing the processes in materials and electronic devices under the influence of cosmic rays in microgravity. The model identifies specific features of formation of the area of radiation defects (ARD) in the electronic materials in microgravity. The mechanism of interaction between the ARD and memory modules in microgravity causing malfunction and failure of onboard electronics is considered. The results of failure of memory modules under real conditions are presented.

  11. The Space Radiation Environment

    NASA Technical Reports Server (NTRS)

    Bourdarie, Sebastien; Xapsos, Michael A.

    2008-01-01

    The effects of the space radiation environment on spacecraft systems and instruments are significant design considerations for space missions. Astronaut exposure is a serious concern for manned missions. In order to meet these challenges and have reliable, cost-effective designs, the radiation environment must be understood and accurately modeled. The nature of the environment varies greatly between low earth orbits, higher earth orbits and interplanetary space. There are both short-term and long-term variations with the phase of the solar cycle. In this paper we concentrate mainly on charged particle radiations. Descriptions of the radiation belts and particles of solar and cosmic origin are reviewed. An overview of the traditional models is presented accompanied by their application areas and limitations. This is followed by discussion of some recent model developments.

  12. A New Electron Source for Laboratory Simulation of the Space Environment

    NASA Technical Reports Server (NTRS)

    Krause, Linda Habash; Everding, Daniel; Bonner, Mathew; Swan, Brian

    2012-01-01

    We have developed a new collimated electron source called the Photoelectron Beam Generator (PEBG) for laboratory and spaceflight applications. This technology is needed to replace traditional cathodes because of serious fundamental weaknesses with the present state of the art. Filament cathodes suffer from numerous practical problems, even if expertly designed, including the dependence of electron emission on filament temperature, short lifetimes (approx 100 hours), and relatively high power (approx 10s of W). Other types of cathodes have solved some of these problems, but they are plagued with other difficult problems, such as the Spindt cathode's extreme sensitivity to molecular oxygen. None to date have been able to meet the demand of long lifetime, robust packaging, and precision energy and flux control. This new cathode design avoids many common pitfalls of traditional cathodes. Specifically, there are no fragile parts, no sensitivity to oxygen, no intrinsic emission dependencies on device temperature, and no vacuum requirements for protecting the source from contamination or damage. Recent advances in high-brightness Light Emitting Diodes (LEDs) have provided the key enabling technology for this new electron source. The LEDs are used to photoeject electrons off a target material of a low work-function, and these photoelectrons are subsequently focused into a laminar beam using electrostatic lenses. The PEBG works by illuminating a target material and steering photoelectrons into a laminar beam using electrostatic lenses

  13. Space Electronics: A Challenging World for Designers

    NASA Technical Reports Server (NTRS)

    Poivey, Christian; LaBel, Kenneth A.

    2004-01-01

    This viewgraph presentation provides an overview of: 1) The Space Radiation Environment; 2) The Effects on Electronics; 3) The Environment in Action; 4) Hardening Approaches to Commercial CMOS Electronics (including device vulnerabilities).

  14. Radiation Assurance for the Space Environment

    NASA Technical Reports Server (NTRS)

    Barth, Janet L.; LaBel, Kenneth A.; Poivey, Christian

    2004-01-01

    The space radiation environment can lead to extremely harsh operating conditions for spacecraft electronic systems. A hardness assurance methodology must be followed to assure that the space radiation environment does not compromise the functionality and performance of space-based systems during the mission lifetime. The methodology includes a definition of the radiation environment, assessment of the radiation sensitivity of parts, worst-case analysis of the impact of radiation effects, and part acceptance decisions which are likely to include mitigation measures.

  15. Space Environments Testbed

    NASA Technical Reports Server (NTRS)

    Leucht, David K.; Koslosky, Marie J.; Kobe, David L.; Wu, Jya-Chang C.; Vavra, David A.

    2011-01-01

    The Space Environments Testbed (SET) is a flight controller data system for the Common Carrier Assembly. The SET-1 flight software provides the command, telemetry, and experiment control to ground operators for the SET-1 mission. Modes of operation (see dia gram) include: a) Boot Mode that is initiated at application of power to the processor card, and runs memory diagnostics. It may be entered via ground command or autonomously based upon fault detection. b) Maintenance Mode that allows for limited carrier health monitoring, including power telemetry monitoring on a non-interference basis. c) Safe Mode is a predefined, minimum power safehold configuration with power to experiments removed and carrier functionality minimized. It is used to troubleshoot problems that occur during flight. d) Operations Mode is used for normal experiment carrier operations. It may be entered only via ground command from Safe Mode.

  16. Complex role of secondary electron emissions in dust grain charging in space environments: measurements on Apollo 11 & 17 dust grains

    NASA Astrophysics Data System (ADS)

    Abbas, Mian; Tankosic, Dragana; Spann, James; Leclair, Andre C.

    Dust grains in various astrophysical environments are generally charged electrostatically by photoelectric emissions with radiation from nearby sources, by electron/ion collisions, and sec-ondary electron emissions. Knowledge of the dust grain charges and equilibrium potentials is important for understanding of a variety of physical and dynamical processes in the interstel-lar medium (ISM), and heliospheric, interplanetary, planetary, and lunar environments. The high vacuum environment on the lunar surface leads to some unusual physical and dynam-ical phenomena involving dust grains with high adhesive characteristics, and levitation and transportation over long distances. It has been well recognized that the charging properties of individual micron/submicron size dust grains are expected to be substantially different from the corresponding values for bulk materials and theoretical models. In this paper we present experimental results on charging of individual dust grains selected from Apollo 11 and Apollo 17 dust samples by exposing them to mono-energetic electron beams in the 10-400 eV energy range. The charging rates of positively and negatively charged particles of 0.2 to 13 µm diam-eters are discussed in terms of the secondary electron emission (SEE) process, which is found to be a complex charging process at electron energies as low as 10-25 eV, with strong parti-cle size dependence. The measurements indicate substantial differences between dust charging properties of individual small size dust grains and of bulk materials.

  17. Phase-Space Density Analysis of the AE-8 Traped Electron and the AP-8 Trapped Proton Model Environments

    SciTech Connect

    Thomas E. Cayton

    2005-08-01

    The AE-8 trapped electron and the AP-8 trapped proton models are used to examine the L-shell variation of phase-space densities for sets of transverse (or 1st) invariants, {mu}, and geometrical invariants, K (related to the first two adiabatic invariants). The motivation for this study is twofold: first, to discover the functional dependence of the phase-space density upon the invariants; and, second, to explore the global structure of the radiation belts within this context. Variation due to particle rest mass is considered as well. The overall goal of this work is to provide a framework for analyzing energetic particle data collected by instruments on Global Positioning System (GPS) spacecraft that fly through the most intense region of the radiation belt. For all considered values of {mu} and K, and for 3.5 R{sub E} < L < 6.5 R{sub E}, the AE-8 electron phase-space density increases with increasing L; this trend--the expected one for a population diffusing inward from an external source--continues to L = 7.5 R{sub E} for both small and large values of K but reverses slightly for intermediate values of K. The AP-8 proton phase-space density exhibits {mu}-dependent local minima around L = 5 R{sub E}. Both AE-8 and AP-8 exhibit critical or cutoff values for the invariants beyond which the flux and therefore the phase-space density vanish. For both electrons and protons, these cutoff values vary systematically with magnetic moment and L-shell and are smaller than those estimated for the atmospheric loss cone. For large magnetic moments, for both electrons and protons, the K-dependence of the phase-space density is exponential, with maxima at the magnetic equator (K = 0) and vanishing beyond a cutoff value, K{sub c}. Such features suggest that momentum-dependent trapping boundaries, perhaps drift-type loss cones, serve as boundary conditions for trapped electrons as well as trapped protons.

  18. Phase-Space Density Analyses of the AE-8 Trapped Electron and the AP-8 Trapped Proton Model Environments

    SciTech Connect

    T.E. Cayton

    2005-08-12

    The AE-8 trapped electron and the AP-8 trapped proton models are used to examine the L-shell variation of phase-space densities for sets of transverse (or 1st) invariants, {mu}, and geometrical invariants, K (related to the first two adiabatic invariants). The motivation for this study is twofold: first, to discover the functional dependence of the phase-space density upon the invariants; and, second, to explore the global structure of the radiation belts within this context. Variation due to particle rest mass is considered as well. The overall goal of this work is to provide a framework for analyzing energetic particle data collected by instruments on Global Positioning System (GPS) spacecraft that fly through the most intense region of the radiation belt. For all considered values of {mu} and K, and for 3.5 R{sub E} < L < 6.5 R{sub E}, the AE-8 electron phase-space density increases with increasing L; this trend--the expected one for a population diffusing inward from an external source--continues to L = 7.5 R{sub E} for both small and large values of K but reverses slightly for intermediate values of K. The AP-8 proton phase-space density exhibits {mu}-dependent local minima around L = 5 R{sub E}. Both AE-8 and AP-8 exhibit critical or cutoff values for the invariants beyond which the flux and therefore the phase-space density vanish. For both electrons and protons, these cutoff values vary systematically with magnetic moment and L-shell and are smaller than those estimated for the atmospheric loss cone. For large magnetic moments, for both electrons and protons, the K-dependence of the phase-space density is exponential, with maxima at the magnetic equator (K = 0) and vanishing beyond a cutoff value, K{sub c}. Such features suggest that momentum-dependent trapping boundaries, perhaps drift-type loss cones, serve as boundary conditions for trapped electrons as well as trapped protons.

  19. Space Electronic Test Engineering

    NASA Technical Reports Server (NTRS)

    Chambers, Rodney D.

    2004-01-01

    The Space Power and Propulsion Test Engineering Branch at NASA Glenn Research center has the important duty of controlling electronic test engineering services. These services include test planning and early assessment of Space projects, management and/or technical support required to safely and effectively prepare the article and facility for testing, operation of test facilities, and validation/delivery of data to customer. The Space Electronic Test Engineering Branch is assigned electronic test engineering responsibility for the GRC Space Simulation, Microgravity, Cryogenic, and Combustion Test Facilities. While working with the Space Power and Propulsion Test Engineering Branch I am working on several different assignments. My primary assignment deals with an electrical hardware unit known as Sunny Boy. Sunny Boy is a DC load Bank that is designed for solar arrays in which it is used to convert DC power form the solar arrays into AC power at 60 hertz to pump back into the electricity grid. However, there are some researchers who decided that they would like to use the Sunny Boy unit in a space simulation as a DC load bank for a space shuttle or even the International Space Station hardware. In order to do so I must create a communication link between a computer and the Sunny Boy unit so that I can preset a few of the limits (such power, set & constant voltage levels) that Sunny Boy will need to operate using the applied DC load. Apart from this assignment I am also working on a hi-tech circuit that I need to have built at a researcher s request. This is a high voltage analog to digital circuit that will be used to record data from space ion propulsion rocket booster tests. The problem that makes building this circuit so difficult is that it contains high voltage we must find a way to lower the voltage signal before the data is transferred into the computer to be read. The solution to this problem was to transport the signal using infrared light which will lower

  20. Microbiology & Toxicology: Space Environment

    NASA Video Gallery

    One key aspect in maintaining crew health and performance during spaceflight missions is the provision of a habitable environment with acceptably low concentrations of microbiological and toxicolog...

  1. Advanced cryocooler electronics for space

    NASA Astrophysics Data System (ADS)

    Harvey, D.; Danial, A.; Davis, T.; Godden, J.; Jackson, M.; McCuskey, J.; Valenzuela, P.

    2004-06-01

    Space pulse-tube cryocoolers require electronics to control the cooling temperature and self-induced vibration. Other functions include engineering diagnostics, telemetry and safety protection of the unit against extreme environments and operational anomalies. The electronics must survive the harsh conditions of launch and orbit, and in some cases severe radiation environments for periods exceeding 10 years. A number of our current generation high reliability radiation hardened electronics units have been launched and others are in various stages of assembly or integration on a number of space flight programs. This paper describes the design features and performance of our next generation flight electronics designed for the STSS payloads. The electronics provides temperature control with better than +/-50 mK short-term stability. Self-induced vibration is controlled to low levels on all harmonics up to the 16th. A unique active power filter limits peak-to-peak reflected ripple current on the primary power bus to less than 3% of the average DC current. The 3 kg unit is capable of delivering 180 W continuous to NGST's high-efficiency cryocooler (HEC).

  2. An Assessment of Molten Metal Detachment Hazards for Electron Beam Welding in the Space Environment: Analysis and Test Results

    NASA Technical Reports Server (NTRS)

    Nunes, A. C., Jr.; Russell, C.; Bhat, B.; Fragomeni, J. M.

    1998-01-01

    Conditions under which molten metal detachments might occur in a space welding environment are analyzed. A weld pool detachment parameter specifying conditions for pool detachment by impact is derived and corroborated by experimental evidence. Impact detachment for the pool is unlikely. Impact detachment for a drop of metal on the end of the weld wire may be possible under extreme conditions. Other potential causes of molten metal detachment considered, vaporization pressure forces and wire flickout from the pool, did not appear to present significant detachment threats.

  3. The space radiation environment

    SciTech Connect

    Robbins, D.E.

    1997-04-30

    There are three primary sources of space radiation: galactic cosmic rays (GCR), trapped belt radiation, and solar particle events (SPE). All are composed of ions, the nuclei of atoms. Their energies range from a few MeV u{sup -1} to over a GeV u{sup -1}. These ions can fragment when they interact with spacecraft materials and produce energetic neutrons and ions of lower atomic mass. Absorbed dose rates inside a typical spacecraft (like the Space Shuttle) in a low inclination (28.5 degrees) orbit range between 0.05 and 2 mGy d{sup -1} depending on the altitude and flight inclination (angle of orbit with the equator). The quality factor of radiation in orbit depends on the relative contributions of trapped belt radiation and GCR, and the dose rate varies both with orbital altitude and inclination. The corresponding equivalent dose rate ranges between 0.1 and 4 mSv d{sup -1}. In high inclination orbits, like that of the Mir Space Station and as is planned for the International Space Station, blood-forming organ (BFO) equivalent dose rates as high as 1.5 mSv d{sup -1}. Thus, on a 1 y mission, a crew member could obtain a total dose of 0.55 Sv. Maximum equivalent dose rates measured in high altitude passes through the South Atlantic Anomaly (SAA) were 10 mSv h{sup -1}. For an interplanetary space mission (e.g., to Mars) annual doses from GCR alone range between 150 mSv y{sup -1} at solar maximum and 580 mSv y{sup -1} at solar minimum. Large SPE, like the October 1989 series, are more apt to occur in the years around solar maximum. In free space, such an event could contribute another 300 mSv, assuming that a warning system and safe haven can be effectively used with operational procedures to minimize crew exposures. Thus, the total dose for a 3 y mission to Mars could exceed 2 Sv.

  4. Internal space charge measurement of materials in a space environment

    NASA Astrophysics Data System (ADS)

    Griseri, V.; Fukunaga, K.; Maeno, T.; Payan, D.; Laurent, C.; Levy, L.

    2003-09-01

    The charging/discharging effect produced by space environment on space vehicles are known but not fully identified yet. Experiments performed in laboratory in vacuum chamber that simulates spatial environment and the most realistic charge condition occurring in space have been developed in the last past forty years. A very small Pulse Electro-Acoustic space charge detection unit (mini-PEA) that can be mounted in a vacuum chamber, to measure internal space charges of materials in-situ during the irradiation has been developed. Several materials used in spatial environment such as Teflon®, and Kapton ® films on addition to PMMA films have been studied. The comparison and the good agreement between measured and calculated depth of penetration for electrons of given energy depending on the material nature contribute in the validation of the detection system and encourage us for further studies and development.

  5. Radiation Effects in the Space Telecommunications Environment

    SciTech Connect

    Fleetwood, Daniel M.; Winokur, Peter S.

    1999-05-17

    Trapped protons and electrons in the Earth's radiation belts and cosmic rays present significant challenges for electronics that must operate reliably in the natural space environment. Single event effects (SEE) can lead to sudden device or system failure, and total dose effects can reduce the lifetime of a telecommmiications system with significant space assets. One of the greatest sources of uncertainty in developing radiation requirements for a space system is accounting for the small but finite probability that the system will be exposed to a massive solar particle event. Once specifications are decided, standard laboratory tests are available to predict the total dose response of MOS and bipolar components in space, but SEE testing of components can be more challenging. Prospects are discussed for device modeling and for the use of standard commercial electronics in space.

  6. Space environment model construction technology

    NASA Astrophysics Data System (ADS)

    Nishimoto, Hironobu; Matsumoto, Haruhisa

    1992-08-01

    A space environment model was constructed based on the results of the review on space environment model conducted in Fiscal Year 1986 and 1987. The space environment model was constructed to collect theories and data required for grasping various physical entities such as radiation, plasma, and spacecraft fragments and so forth, and to enable quantitative prediction of their time wise, spacial distribution and their effects such as electrification and material deterioration, and its system structure and functions were shown. The Technical Data Acquisition Equipment (TEDA) installed onboard the Engineering Test Satellite-5 (ETS-5) consist of various satellite environment monitors and component and material deterioration monitors for the purpose of acquiring technical data required for design and evaluation for satellite development. Review was conducted to clarify the correlation between each TEDA data and to apply the result in constructing the satellite environment model. Correlation between each TEDA data was made clear.

  7. Space Environment Information System (SPENVIS)

    NASA Astrophysics Data System (ADS)

    Kruglanski, Michel; de Donder, Erwin; Messios, Neophytos; Hetey, Laszlo; Calders, Stijn; Evans, Hugh; Daly, Eamonn

    SPENVIS is an ESA operational software developed and maintained at BIRA-IASB since 1996. It provides standardized access to most of the recent models of the hazardous space environment, through a user-friendly Web interface (http://www.spenvis.oma.be/). The system allows spacecraft engineers to perform a rapid analysis of environmental problems related to natural radiation belts, solar energetic particles, cosmic rays, plasmas, gases, magnetic fields and micro-particles. Various reporting and graphical utilities and extensive help facilities are included to allow engineers with relatively little familiarity to produce reliable results. SPENVIS also contains an active, integrated version of the ECSS Space Environment Standard and access to in-flight data on the space environment. Although SPENVIS in the first place is designed to help spacecraft designers, it is also used by technical universities in their educational programs. In the framework of the ESA Space Situational Awareness Preparatory Programme, SPENVIS will be part of the initial set of precursor services of the Space Weather segment. SPENVIS includes several engineering models to assess to effects of the space environment on spacecrafts such as surface and internal charging, energy deposition, solar cell damage and SEU rates. The presentation will review how such models could be connected to in situ measurements or forecasting models of the space environment in order to produce post event analysis or in orbit effects alert. The last developments and models implemented in SPENVIS will also be presented.

  8. Space station neutral external environment

    NASA Technical Reports Server (NTRS)

    Ehlers, H.; Leger, L.

    1988-01-01

    Molecular contamination levels arising from the external induced neutral environment of the Space Station (Phase 1 configuration) were calculated using the MOLFLUX model. Predicted molecular column densities and deposition rates generally meet the Space Station contamination requirements. In the doubtful cases of deposition due to materials outgassing, proper material selection, generally excluding organic products exposed to the external environment, must be considered to meet contamination requirements. It is important that the Space Station configuration, once defined, is not significantly modified to avoid introducing new unacceptable contamination sources.

  9. Space Debris Environment Remediation Concepts

    NASA Technical Reports Server (NTRS)

    Johnson, Nicholas L.; Klinkrad, Heiner

    2009-01-01

    Long-term projections of the space debris environment indicate that even drastic measures, such as an immediate, complete halt of launch and release activities, will not result in a stable environment of man-made space objects. Collision events between already existing space hardware will within a few decades start to dominate the debris population, and result in a net increase of the space debris population, also in size regimes which may cause further catastrophic collisions. Such a collisional cascading will ultimately lead to a run-away situation ("Kessler syndrome"), with no further possibility of human intervention. The International Academy of Astronautics (IAA) has been investigating the status and the stability of the space debris environment in several studies by first looking into space traffic management possibilities and then investigating means of mitigating the creation of space debris. In an ongoing activity, an IAA study group looks at ways of active space debris environment remediation. In contrast to the former mitigation study, the current activity concentrates on the active removal of small and large objects, such as defunct spacecraft, orbital stages, and mission-related objects, which serve as a latent mass reservoir that fuels initial catastrophic collisions and later collisional cascading. The paper will outline different mass removal concepts, e.g. based on directed energy, tethers (momentum exchange or electrodynamic), aerodynamic drag augmentation, solar sails, auxiliary propulsion units, retarding surfaces, or on-orbit capture. Apart from physical principles of the proposed concepts, their applicability to different orbital regimes, and their effectiveness concerning mass removal efficiency will be analyzed. The IAA activity on space debris environment remediation is a truly international project which involves more than 23 contributing authors from 9 different nations.

  10. Space Debris Environent Remediation Concepts

    NASA Astrophysics Data System (ADS)

    Klinkrad, H.; Johnson, N. L.

    2009-03-01

    Long-term projections of the space debris environment indicate that even drastic measures, such as an immediate, complete halt of launch and release activities, will not result in a stable environment of man-made space objects. Collision events between already existing space hardware will within a few decades start to dominate the debris population, and result in a net increase of the space debris population, also at sizes which may cause further catastrophic collisions. A collisional cascading may ultimately lead to a run-away situation ("Kessler syndrome"), with no further possibility of human intervention.The International Academy of Astronautics (IAA) has been investigating the status and the stability of the space debris environment in several studies by first looking into space traffic management possibilities, and then investigating means of mitigating the creation of space debris. In an on-going activity, an IAA study group looks into methods of active space debris environment remediation. In contrast to the former mitigation study, the current activity concentrates on the active removal of large objects, such as defunct spacecraft, orbital stages, and mission-related objects, which serve as a latent mass reservoir that fuels initial castastrophic collisions and later collisional cascading. The paper will outline different mass removal concepts, e.g. based on directed energy, tethers (momentum exchange or electro-dynamic), aerodynamic drag augmentation, solar sails, auxiliary propulsion units, retarding surfaces, or on-orbit capture. Apart from physical principles of the proposed concepts, their applicability to different orbital regimes, and their effectiveness concerning mass removal efficiency will be discussed.

  11. Modeling the Space Radiation Environment

    NASA Technical Reports Server (NTRS)

    Xapsos, Michael A.

    2006-01-01

    There has been a renaissance of interest in space radiation environment modeling. This has been fueled by the growing need to replace long time standard AP-9 and AE-8 trapped particle models, the interplanetary exploration initiative, the modern satellite instrumentation that has led to unprecedented measurement accuracy, and the pervasive use of Commercial off the Shelf (COTS) microelectronics that require more accurate predictive capabilities. The objective of this viewgraph presentation was to provide basic understanding of the components of the space radiation environment and their variations, review traditional radiation effects application models, and present recent developments.

  12. Living with a Star Space Environment Testbed

    NASA Technical Reports Server (NTRS)

    Barth, Janet

    2003-01-01

    Summary of activities: (1) FYO1 NRA - Model development and data mining. (2) FY03 NRA - Flight investigations. (3) SET carrier development. (4) Study for accommodation of SET carrier to support advanced detectors. (5) Collaboration with other programs: LWS TR&T to maximize synergy between TR&T space environment research and SET space environment effects research. LWS Data System to optimize dissemination of SET data. NASA Electronic Parts and Packaging Program to leverage ground testing of technologies. Defense Threat Reduction Agency to leverage ground testing and common interests in advanced detectors. and Air Force Research Laboratory to leverage flight opportunities. (6) Education and Public Outreach.

  13. Space Radiation Effects on Electronics: Simple Concepts and New Challenges

    NASA Technical Reports Server (NTRS)

    LaBel, Kenneth A.

    2004-01-01

    This viewgraph presentation covers the following topics: 1) The Space Radiation Environment; 2) The Effects on Electronics; 3) The Environment in Action; 4) NASA Approaches to Commercial Electronics; 5) Final Thoughts.

  14. Space environment measurements by JAXA satellites and ISS/JEM

    NASA Astrophysics Data System (ADS)

    Obara, Takahiro; Matsumoto, Haruhisa; Koga, Kiyokazu

    2012-02-01

    In order to monitor space environment and its temporal variations, JAXA Space Environment Group has been developing space radiation detectors as well as magnetometers and installing them on Low Earth Orbit (LEO) satellites, Geostationary Orbit (GEO) satellites, Geostationary Transfer Orbit (GTO) satellite, Quasi Zenith Orbit (QZO) satellite and Japanese Experimental Module (JEM) of the International Space Station (ISS). We are using these space environment data to know the situation of space environment and to provide warning messages to the satellite operators as well as ISS/JEM manager, when the space environment will be harmful. Based on our observation data, we also have constructed an advanced electron belt model for the use in satellite manufacturing. With space radiation data obtained by JAXA satellites and ISS, some findings related to the space radiation environment have been obtained. We will review our activities related to the space environment research and development in JAXA.

  15. Space environment effects (M0006)

    NASA Technical Reports Server (NTRS)

    Angelo, J. A., Jr.; Madonna, R. G.; Altadonna, L. P.; Dagostino, M. D.; Chang, J. Y.; Alfano, R. R.; Caplan, V. L.

    1984-01-01

    The effects of long term exposure to the near Earth space environment on advanced electrooptical and radiation sensor components were examined. The effect of long duration spaceflight on the germination rate of selected terrestrial plant seeds is observed in exobiological experiments.

  16. RADECS Short Course Session I: The Space Radiation Environment

    NASA Technical Reports Server (NTRS)

    Xapsos, Michael; Bourdarie, Sebastien

    2007-01-01

    The presented slides and accompanying paper focus on radiation in the space environment. Since space exploration has begun it has become evident that the space environment is a highly aggressive medium. Beyond the natural protection provided by the Earth's atmosphere, various types of radiation can be encountered. Their characteristics (energy and nature), origins and distributions in space are extremely variable. This environment degrades electronic systems and on-board equipment in particular and creates radiobiological hazards during manned space flights. Based on several years of space exploration, a detailed analysis of the problems on satellites shows that the part due to the space environment is not negligible. It appears that the malfunctions are due to problems linked to the space environment, electronic problems, design problems, quality problems, other issues, and unexplained reasons. The space environment is largely responsible for about 20% of the anomalies occurring on satellites and a better knowledge of that environment could only increase the average lifetime of space vehicles. This naturally leads to a detailed study of the space environment and of the effects that it induces on space vehicles and astronauts. Sources of radiation in the space environment are discussed here and include the solar activity cycle, galactic cosmic rays, solar particle events, and Earth radiation belts. Future challenges for space radiation environment models are briefly addressed.

  17. Space Environment (Natural and Induced)

    NASA Technical Reports Server (NTRS)

    Kim, Myung-Hee Y.; George, Kerry A.; Cucinotta, Francis A.

    2007-01-01

    Considerable effort and improvement have been made in the study of ionizing radiation exposure occurring in various regions of space. Satellites and spacecrafts equipped with innovative instruments are continually refining particle data and providing more accurate information on the ionizing radiation environment. The major problem in accurate spectral definition of ionizing radiation appears to be the detailed energy spectra, especially at high energies, which is important parameter for accurate radiation risk assessment. Magnitude of risks posed by exposure to radiation in future space missions is subject to the accuracies of predictive forecast of event size of SPE, GCR environment, geomagnetic fields, and atmospheric radiation environment. Although heavy ion fragmentations and interactions are adequately resolved through laboratory study and model development, improvements in fragmentation cross sections for the light nuclei produced from HZE nuclei and their laboratory validation are still required to achieve the principal goal of planetary GCR simulation at a critical exposure site. More accurate prediction procedure for ionizing radiation environment can be made with a better understanding of the solar and space physics, fulfillment of required measurements for nuclear/atomic processes, and their validation and verification with spaceflights and heavy ion accelerators experiments. It is certainly true that the continued advancements in solar and space physics combining with physical measurements will strengthen the confidence of future manned exploration of solar system. Advancements in radiobiology will surely give the meaningful radiation hazard assessments for short and long term effects, by which appropriate and effective mitigation measures can be placed to ensure that humans safely live and work in the space, anywhere, anytime.

  18. Space electronics technology summary

    NASA Technical Reports Server (NTRS)

    1976-01-01

    An overview is given of current electronics R and D activities, potential future thrusts, and related NASA payoffs. Major increases in NASA mission return and significant concurrent reductions in mission cost appear possible through a focused, long range electronics technology program. The overview covers: guidance assessments, navigation and control, and sensing and data acquisition processing, storage, and transfer.

  19. Nuclear and Non-Ionizing Energy-Loss of Electrons with Low and Relativistic Energies in Materials and Space Environment

    NASA Astrophysics Data System (ADS)

    Boschini, M. J.; Consolandi, C.; Gervasi, M.; Giani, S.; Grandi, D.; Ivanchenko, V.; Nieminem, P.; Pensotti, S.; Rancoita, P. G.; Tacconi, M.

    2012-08-01

    The treatment of the electron-nucleus interaction based on the Matt differential cross section was extended to account for effects due to screened Coulomb potentials, finite sizes and finite rest masses of nuclei for electrons above 200keV and up to ultra high energies. This treatment allows one to determine both the total and differential cross sections, thus, subsequently to calculate the resulting nuclear and non-ionizing stopping powers. Above a few hundreds of MeV, neglecting the effect due to finite rest masses of recoil nuclei the stopping power and NIEL result to be largely underestimated. While, above a few tens of MeV, the finite size ofthe nuclear target prevents a further large increase of stopping powers which approach almost constant values.

  20. Near Space Environments: Tethering Systems

    NASA Technical Reports Server (NTRS)

    Lucht, Nolan R.

    2013-01-01

    Near Space Environments, the Rocket University (Rocket U) program dealing with high altitude balloons carrying payloads into the upper earth atmosphere is the field of my project. The tethering from balloon to payload is the specific system I am responsible for. The tethering system includes, the lines that tie the payload to the balloon, as well as, lines that connect payloads together, if they are needed, as well as how to sever the tether to release payloads from the balloon. My objective is to design a tethering system that will carry a payload to any desired altitude and then sever by command at any given point during flight.

  1. Environment of Space Interactions with Space Systems

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The primary product of this research project was a computer program named SAVANT. This program uses the Displacement Damage Dose (DDD) method of calculating radiation damage to solar cells. This calculation method was developed at the Naval Research Laboratory, and uses fundamental physical properties of the solar cell materials to predict radiation damage to the solar cells. This means that fewer experimental measurements are required to characterize the radiation damage to the cells, which results in a substantial cost savings to qualify solar cells for orbital missions. In addition, the DDD method makes it easier to characterize cells that are already being used, but have not been fully tested using the older technique of characterizing radiation damage. The computer program combines an orbit generator with NASA's AP-8 and AE-8 models of trapped protons and electrons. This allows the user to specify an orbit, and the program will calculate how the spacecraft moves during the mission, and the radiation environment that it encounters. With the spectrum of the particles, the program calculates how they would slow down while traversing the coverglass, and provides a slowed-down spectrum.

  2. The natural space environment: Effects on spacecraft

    NASA Technical Reports Server (NTRS)

    James, Bonnie F.; Norton, O. W. (Compiler); Alexander, Margaret B. (Editor)

    1994-01-01

    The effects of the natural space environments on spacecraft design, development, and operation are the topic of a series of NASA Reference Publications currently being developed by the Electromagnetics and Environments Branch, Systems Analysis and Integration Laboratory, Marshall Space Flight Center. This primer provides an overview of the natural space environments and their effect on spacecraft design, development, and operations, and also highlights some of the new developments in science and technology for each space environment. It is hoped that a better understanding of the space environment and its effect on spacecraft will enable program management to more effectively minimize program risks and costs, optimize design quality, and successfully achieve mission objectives.

  3. Space Environment Effects on Silicone Seal Materials

    NASA Technical Reports Server (NTRS)

    deGroh, Henry C., III; Daniels, Christopher C.; Dever, Joyce A.; Miller, Sharon K.; Waters, Deborah L.; Finkbeiner, Joshua R.; Dunlap, Patrick H.; Steinetz, Bruce M.

    2010-01-01

    A docking system is being developed by the NASA to support future space missions. It is expected to use redundant elastomer seals to help contain cabin air during dockings between two spacecraft. The sealing surfaces are exposed to the space environment when vehicles are not docked. In space, the seals will be exposed to temperatures between 125 to -75 C, vacuum, atomic oxygen, particle and ultraviolet radiation, and micrometeoroid and orbital debris (MMOD). Silicone rubber is the only class of space flight-qualified elastomeric seal material that functions across the expected temperature range. NASA Glenn has tested three silicone elastomers for such seal applications: two provided by Parker (S0899-50 and S0383-70) and one from Esterline (ELA-SA-401). The effects of atomic oxygen (AO), UV and electron particle radiation, and vacuum on the properties of these three elastomers were examined. Critical seal properties such as leakage, adhesion, and compression set were measured before and after simulated space exposures. The S0899-50 silicone was determined to be inadequate for extended space seal applications due to high adhesion and intolerance to UV, but both S0383-70 and ELA-SA-401 seals were adequate.

  4. Designing Electronic Collaborative Learning Environments

    ERIC Educational Resources Information Center

    Kirschner, Paul; Strijbos, Jan-Willem; Kreijns, Karel; Beers, Pieter Jelle

    2004-01-01

    Electronic collaborative learning environments for learning and working are in vogue. Designers design them according to their own constructivist interpretations of what collaborative learning is and what it should achieve. Educators employ them with different educational approaches and in diverse situations to achieve different ends. Students use…

  5. Electronics for Low Temperature Space Exploration Missions

    NASA Technical Reports Server (NTRS)

    Patterson, Richard L.; Hammoud, Ahmad; Elbuluk, Malik

    2007-01-01

    Exploration missions to outer planets and deep space require spacecraft, probes, and on-board data and communication systems to operate reliably and efficiently under severe harsh conditions. On-board electronics, in particular those in direct exposures to the space environment without any shielding or protection, will encounter extreme low temperature and thermal cycling in their service cycle in most of NASA s upcoming exploration missions. For example, Venus atmosphere, Jupiter atmosphere, Moon surface, Pluto orbiter, Mars, comets, Titan, Europa, and James Webb Space Telescope all involve low-temperature surroundings. Therefore, electronics for space exploration missions need to be designed for operation under such environmental conditions. There are ongoing efforts at the NASA Glenn Research Center (GRC) to establish a database on the operation and reliability of electronic devices and circuits under extreme temperature operation for space applications. This work is being performed under the Extreme Temperature Electronics Program with collaboration and support of the NASA Electronic Parts and Packaging (NEPP) Program. The results of these investigations will be used to establish safe operating areas and to identify degradation and failure modes, and the information will be disseminated to mission planners and system designers for use as tools for proper part selection and in risk mitigation. An overview of this program along with experimental data will be presented.

  6. Environment resistant windows for space greenhouses

    NASA Astrophysics Data System (ADS)

    Gan, B. K.; Kondyurin, A.; Bilek, M.; Latella, B. A.

    One of the ways of providing a self-sustainable environment in space is to provide food and life support systems through bio-regenerative power i e a greenhouse It is an essential structure because it provides oxygen and food in a controlled environment The windows and frames of a greenhouse are generally made from glass or polymer panels which allow sunlight to enter Polymers are useful because they are lightweight transparent corrosion resistant and inexpensive However windows which are made from polymeric materials or polymer-based composites suffer from accelerated erosion due to the presence of atomic oxygen in space environment A metal oxide deposited on the surface of the polymer will aid in the resistance of these polymers to chemical attack as well as improving surface hardness and wear resistance characteristics In this study we modified the surfaces of polycarbonate PC by deposition and implantation of thin and transparent aluminium oxide Al 2 O 3 coatings The Al 2 O 3 plasma was produced using a cathodic arc deposition system with a combination of plasma immersion ion implantation PIII The coatings were then tested for resistance to atomic oxygen environment These were carried out by monitoring the mass loss of the deposited samples exposed to an rf oxygen plasma The morphology and optical properties of the coatings before and after exposure to oxygen plasma were then examined using electron microscopy profilometry and ellipsometry Mechanical properties and adhesion characteristics of the coatings

  7. Organic polymer materials in the space environment

    NASA Astrophysics Data System (ADS)

    Chen, Jun; Ding, Nengwen; Li, Zhifeng; Wang, Wei

    2016-05-01

    The space environment is a complex environment full of microgravity, high vacuum, high and low temperature, strong radiation and plasma. Polymers used in the space environment will inevitably experience aging and degradation which result in changes of the material mechanics, physics and chemical properties, until they lose usefulness. To make a material that can be used for a long time and whose performance is not changed in the space environment, its ability to resist environmental factors must be excellent. Therefore, this paper provides an introduction to the harmful conditions in the space environment and their effects on the polymers, also it reviews the aging mechanisms of the adhesives used in the space environment and the effect of thermal cycling, stress, electromagnetic radiation and ionizing particles on the properties of polymers and optical devices, to provide the reference basis for selection, modification and reliability analysis of materials used in the space environment.

  8. Space Environment Testing of Photovoltaic Array Systems

    NASA Technical Reports Server (NTRS)

    Phillips, Brandon; Schneider, Todd A.; Vaughn, Jason A.; Wright, Kenneth H.

    2015-01-01

    To successfully operate a photovoltaic (PV) array system in space requires planning and testing to account for the effects of the space environment. It is critical to understand space environment interactions not only on the PV components, but also the array substrate materials, wiring harnesses, connectors, and protection circuitry.

  9. Magnetic Environment in Geo-space

    NASA Astrophysics Data System (ADS)

    Yumoto, Kiyohumi

    In order to understand the complexity in the Sun-Earth system, the Space Environment Research Center, Kyushu University will conduct global magnetic network observations for space weather studies during the international CAWSES period (2004-2008). In this paper, we will introduce magnetic environment in geo-space and our MAGDAS/CPMN system.

  10. Radiation Hardened Electronics for Extreme Environments

    NASA Technical Reports Server (NTRS)

    Keys, Andrew S.; Watson, Michael D.

    2007-01-01

    The Radiation Hardened Electronics for Space Environments (RHESE) project consists of a series of tasks designed to develop and mature a broad spectrum of radiation hardened and low temperature electronics technologies. Three approaches are being taken to address radiation hardening: improved material hardness, design techniques to improve radiation tolerance, and software methods to improve radiation tolerance. Within these approaches various technology products are being addressed including Field Programmable Gate Arrays (FPGA), Field Programmable Analog Arrays (FPAA), MEMS Serial Processors, Reconfigurable Processors, and Parallel Processors. In addition to radiation hardening, low temperature extremes are addressed with a focus on material and design approaches.

  11. Advances in Space Environment Research - Volume I

    NASA Astrophysics Data System (ADS)

    Chian, A. C.-L.

    2003-10-01

    Advances in Space Environment Research - Volume I contains the proceedings of two international workshops, the World Space Environment Forum (WSEF2002) and the High Performance Computing in Space Environment Research (HPC2002), organized by the World Institute for Space Environment Research (WISER) from 22 July to 2 August 2002 in Adelaide, Australia. The articles in this volume review the state-of-the-art of the theoretical, computational and observational studies of the physical processes of Sun-Earth connections and Space Environment. They cover six topical areas: Sun/Heliosphere, Magnetosphere/Bow Shock, Ionosphere/Atmosphere, Space Weather/Space Climate, Space Plasma Physics/Astrophysics, and Complex/Intelligent Systems. The authors are leading space physicists from 20 countries/regions, representing the WISER international network of research and training centers of excellence dedicated to promote cooperation in cutting-edge space environment research and training of first-rate space scientists, and to link nations for the peaceful use of the space environment. This volume is useful for space physicists, astrophysicists and plasma physicists; and can be adopted as a reference book for advanced undergraduate and postgraduate students. Link: http://www.wkap.nl/prod/b/1-4020-1278-0

  12. Space Shuttle externally induced environment compared with Skylab's natural environment

    NASA Technical Reports Server (NTRS)

    Susko, Michael

    1990-01-01

    Electret measurements obtained of the particulate contamination environment within the Space Shuttle Orbiter's cargo bay are presently compared with ground measurements of the particulates emitted by the Shuttle's SRBs, as well as with the expected natural particulate environment as measured by Skylab. Chemical analysis is shown to reveal the difference between natural and anthropogenic space debris; the most probable primary source of the Space Shuttle's particulate environment is the SRB exhaust.

  13. Harsh environments electronics : downhole applications.

    SciTech Connect

    Vianco, Paul Thomas

    2011-03-01

    The development and operational sustainment of renewable (geothermal) and non-renewable (fossil fuel) energy resources will be accompanied by increasingly higher costs factors: exploration and site preparation, operational maintenance and repair. Increased government oversight in the wake of the Gulf oil spill will only add to the cost burden. It is important to understand that downhole conditions are not just about elevated temperatures. It is often construed that military electronics are exposed to the upper limit in terms of extreme service environments. Probably the harshest of all service conditions for electronics and electrical equipment are those in oil, gas, and geothermal wells. From the technology perspective, advanced materials, sensors, and microelectronics devices are benefificial to the exploration and sustainment of energy resources, especially in terms of lower costs. Besides the need for the science that creates these breakthroughs - there is also a need for sustained engineering development and testing. Downhole oil, gas, and geothermal well applications can have a wide range of environments and reliability requirements: Temperature, Pressure, Vibration, Corrosion, and Service duration. All too frequently, these conditions are not well-defifined because the application is labeled as 'high temperature'. This ambiguity is problematic when the investigation turns to new approaches for electronic packaging solutions. The objective is to develop harsh environment, electronic packaging that meets customer requirements of cost, performance, and reliability. There are a number of challenges: (1) Materials sets - solder alloys, substrate materials; (2) Manufacturing process - low to middle volumes, low defect counts, new equipment technologies; and (3) Reliability testing - requirements documents, test methods and modeling, relevant standards documents. The cost to develop and sustain renewable and non-renewable energy resources will continue to escalate

  14. Electronics for Deep Space Cryogenic Applications

    NASA Technical Reports Server (NTRS)

    Patterson, R. L.; Hammond, A.; Dickman, J. E.; Gerber, S. S.; Elbuluk, M. E.; Overton, E.

    2002-01-01

    Deep space probes and planetary exploration missions require electrical power management and control systems that are capable of efficient and reliable operation in very cold temperature environments. Typically, in deep space probes, heating elements are used to keep the spacecraft electronics near room temperature. The utilization of power electronics designed for and operated at low temperature will contribute to increasing efficiency and improving reliability of space power systems. At NASA Glenn Research Center, commercial-off-the-shelf devices as well as developed components are being investigated for potential use at low temperatures. These devices include semiconductor switching devices, magnetics, and capacitors. Integrated circuits such as digital-to-analog and analog-to-digital converters, DC/DC converters, operational amplifiers, and oscillators are also being evaluated. In this paper, results will be presented for selected analog-to-digital converters, oscillators, DC/DC converters, and pulse width modulation (PWM) controllers.

  15. Analog environments in space human factors

    NASA Technical Reports Server (NTRS)

    Connors, Mary M.

    1992-01-01

    An account is given of what has been learned from space analog environments, which mimic such significant features of space as isolation, confinement, risk, and deprivation; emphasis is placed on the especially successful environments constituted by extended submarine research, undersea habitats, and Antarctic station wintering. Attention is also given to the advantages and limitations of the use of analog environments for space human factors research, and possibilities for such research efforts' management.

  16. Complex Role of Secondary Electron Emissions in Dust Grain Charging in Space Environments: Measurements on Apollo 11 and 17 Dust Grains

    NASA Technical Reports Server (NTRS)

    Abbas, M. M.; Tankosic, D.; Spann, J. F.; LeClair, A. C.

    2010-01-01

    Dust grains in various astrophysical environments are generally charged electrostatically by photoelectric emissions with radiation from nearby sources, or by electron/ion collisions by sticking or secondary electron emissions. Knowledge of the dust grain charges and equilibrium potentials is important for understanding of a variety of physical and dynamical processes in the interstellar medium (ISM), and heliospheric, interplanetary, planetary, and lunar environments. The high vacuum environment on the lunar surface leads to some unusual physical and dynamical phenomena involving dust grains with high adhesive characteristics, and levitation and transportation over long distances. It has been well recognized that the charging properties of individual micron/submicron size dust grains are expected to be substantially different from the corresponding values for bulk materials and theoretical models. In this paper we present experimental results on charging of individual dust grains selected from Apollo 11 and Apollo 17 dust samples by exposing them to mono-energetic electron beams in the 10- 400 eV energy range. The charging rates of positively and negatively charged particles of approximately 0.2 to 13 microns diameters are discussed in terms of the secondary electron emission (SEE) process, which is found to be a complex charging process at electron energies as low as 10-25 eV, with strong particle size dependence. The measurements indicate substantial differences between dust charging properties of individual small size dust grains and of bulk materials.

  17. Cryogenic Electronics Being Developed for Space Operation

    NASA Technical Reports Server (NTRS)

    Patterson, Richard L.; Hammoud, Ahmad; Gerber, Scott S.

    2002-01-01

    Planetary exploration missions and deep space probes require electrical power management and control systems that can operate efficiently and reliably in very low temperature environments. Presently, spacecraft operating in the cold environment of deep space carry a large number of radioisotope heating units to maintain the surrounding temperature of the onboard electronics at approximately 20 C. Electronics capable of operation at cryogenic temperatures would not only tolerate the hostile environment of deep space but also reduce system size and weight by eliminating or reducing the radioisotope heating units and their associate structures. Thereby, such electronics would reduce system development as well as launch costs. In addition, power electronic circuits designed for operation at low temperatures are expected to result in more efficient systems than those at room temperature. This improvement results because semiconductor and dielectric materials have better behavior and tolerance in their electrical and thermal properties at low temperatures. The Low Temperature Electronics Program at the NASA Glenn Research Center is focusing on the research and development of electrical components, circuits, and systems suitable for applications in the aerospace environment and in deep space exploration missions. Research is being conducted on devices and systems for reliable use down to cryogenic temperatures. Some of the commercial off-the-shelf as well as developed components that are being characterized include semiconductor switching devices, resistors, magnetics, and capacitors. Semiconductor devices and integrated circuits including digital-to-analog and analog-to-digital converters, dc-dc converters, operational amplifiers, and oscillators are also being investigated for potential use in low-temperature applications. For example, the output response of an advanced oscillator at room temperature and at -190 C is shown. Most oscillators can operate at temperatures

  18. Space Environment Effects on Materials : An Overview

    NASA Technical Reports Server (NTRS)

    Garrett, Henry B.

    2006-01-01

    A general overview on the space environment and its effects on materials is presented. The topics include: 1) Impact of Space Effects on Spacecraft Costs; 2) Space Environment Effects on Spacecraft by Source; 3) Primary Source of Space Effects: The Sun; 4) The Earth's Environment; 5) Trapped Radiation Belts; 6) Aurora Are Everywhere; 7) Spacecraft Interactions; 8) Atmospheric Effects; 9) Contaminant Effects on Materials; 10) Meteoroid/Debris Effects on Materials; 11) Spacecraft Surface Charging; 12) Surface Discharge Effects; 13) Internal Electrostatic Discharge--Satellite Killer; 14) Plasma Interactions DS-1 Ion Engines; 15) Radiation Effects on Spacecraft Systems and Materials; 16) Total Ionizing Dose Effects Total Ionizing Dose Effects; 17) Man-Made Sources of Space Effects Man-Made Sources of Space Effects; and 18) Space Environments Versus Interactions.

  19. The AE-8 trapped electron model environment

    NASA Technical Reports Server (NTRS)

    Vette, James I.

    1991-01-01

    The machine sensible version of the AE-8 electron model environment was completed in December 1983. It has been sent to users on the model environment distribution list and is made available to new users by the National Space Science Data Center (NSSDC). AE-8 is the last in a series of terrestrial trapped radiation models that includes eight proton and eight electron versions. With the exception of AE-8, all these models were documented in formal reports as well as being available in a machine sensible form. The purpose of this report is to complete the documentation, finally, for AE-8 so that users can understand its construction and see the comparison of the model with the new data used, as well as with the AE-4 model.

  20. The Space Environment from LEO to Deep Space

    NASA Technical Reports Server (NTRS)

    Barth, Janet L.

    2003-01-01

    This viewgraph presentation reviews several space environments, and the hazards they pose to spacecraft operations. The presentation covers solar activity effects, galactic cosmic rays, near Earth environments including the magnetosphere, thermosphere, ionsophere, and plasmasphere, single event upsets, micrometeoroids, space debris, and an overview of conditions on other planets, especially Jupiter.

  1. Contaminant ions and waves in the space station environment

    NASA Technical Reports Server (NTRS)

    Murphy, G. B.

    1988-01-01

    The probable plasma (ions and electrons) and plasma wave environment that will exist in the vicinity of the Space Station and how this environment may affect the operation of proposed experiments are discussed. Differences between quiescent operational periods and non-operational periods are also addressed. Areas which need further work are identified and a course of action suggested.

  2. The NASA Space Environment Simulation Laboratory

    NASA Technical Reports Server (NTRS)

    Jost, R. J.

    1982-01-01

    The NASA Space Environment Simulation Laboratory (SESL) features a chamber for studying specific space plasma physics phenomena. The test chamber, an upright domed cylinder having a 17 m diam and a 27 m height for an inner working volume, is lined with magnetic field generator coils. The chamber pressure is nominally 1/1,000,000th torr. Equipment positioning is carried out by remote control from outside guided by a closed circuit television system. Plasma is generated in the chamber by means of a 30 cm Kaufman thruster which produces ion densities of 100,000-1,000,000/cu cm. The ion bulk flow energy is in the range of 20-50 eV and a charge exchange with the ambient gas produces a cold isotropic ion component. Langmuir probes provide measurements of the electron temperature and density, and the composition and pressure are monitored by mass spectrometry and ion gages. Experiments have been performed on electron beam-plasma interactions, VLF antenna impedance measurements, and high voltage plasma sheaths which may be encountered by spacecraft.

  3. The Sun and Earth's Space Environment

    NASA Technical Reports Server (NTRS)

    Gopalswamy, N.

    2009-01-01

    Earth's space environment is closely controlled by solar variability over various time scales. Solar variability is characterized by its output in the form of mass and electromagnetic output. Solar mass emission also interacts with mass entering into the heliosphere in the form of cosmic rays and neutral material. This paper provides an overview of how the solar variability affects Earth's space environment.

  4. FPGAs in Space Environment and Design Techniques

    NASA Technical Reports Server (NTRS)

    Katz, Richard B.; Day, John H. (Technical Monitor)

    2001-01-01

    This viewgraph presentation gives an overview of Field Programmable Gate Arrays (FPGA) in the space environment and design techniques. Details are given on the effects of the space radiation environment, total radiation dose, single event upset, single event latchup, single event transient, antifuse technology and gate rupture, proton upsets and sensitivity, and loss of functionality.

  5. Environment and the Space Program

    ERIC Educational Resources Information Center

    Schirra, Walter W., Jr.

    1969-01-01

    Data collected at projected space station will contribute to solution of environmental problems on earth and will enable more efficient use of earth's natural resources. Adapted from commencement address delivered at Newark College of Engineering, June 5, 1969. (WM)

  6. E-Textile Antennas for Space Environments

    NASA Technical Reports Server (NTRS)

    Kennedy, Timothy F.; Fink, Patrick W.; Chu, Andrew W.

    2007-01-01

    The ability to integrate antennas and other radio frequency (RF) devices into wearable systems is increasingly important as wireless voice, video, and data sources become ubiquitous. Consumer applications including mobile computing, communications, and entertainment, as well as military and space applications for integration of biotelemetry, detailed tracking information and status of handheld tools, devices and on-body inventories are driving forces for research into wearable antennas and other e-textile devices. Operational conditions for military and space applications of wireless systems are often such that antennas are a limiting factor in wireless performance. The changing antenna platform, i.e. the dynamic wearer, can detune and alter the radiation characteristics of e-textile antennas, making antenna element selection and design challenging. Antenna designs and systems that offer moderate bandwidth, perform well with flexure, and are electronically reconfigurable are ideally suited to wearable applications. Several antennas, shown in Figure 1, have been created using a NASA-developed process for e-textiles that show promise in being integrated into a robust wireless system for space-based applications. Preliminary characterization of the antennas with flexure indicates that antenna performance can be maintained, and that a combination of antenna design and placement are useful in creating robust designs. Additionally, through utilization of modern smart antenna techniques, even greater flexibility can be achieved since antenna performance can be adjusted in real-time to compensate for the antenna s changing environment.

  7. NASA's Space Environments and Effects (SEE) Program

    NASA Technical Reports Server (NTRS)

    Minor, Jody

    2001-01-01

    The return of the Long Duration Exposure Facility (LDEF) in 1990 brought a wealth of space exposure data on materials, paints, solar cells, adhesives and other data on the many space environments. The effects of the harsh space environments can provide damaging or even disabling effects on a spacecraft, its sub-systems, materials and instruments. In partnership with industry, academia, and other US and international government agencies, the National Aeronautics & Space Administration's (NASA's) Space Environments & Effects (SEE) Program defines the space environments and provides technology development to accommodate or mitigate these harmful environments on the spacecraft. This program (agency-wide in scope but managed at the Marshall Space Flight Center) provides a very comprehensive and focused approach to understanding the space environment. It does this by defining the best techniques for both flight- and groundbased experimentation, updating models which predict both the environments and the environmental effects on spacecraft and ensuring that this information is properly maintained and inserted into spacecraft design programs. This paper will describe the current SEE Program and discuss several current technology development activities associated with the spacecraft charging phenomenon.

  8. ONERA's contribution to space environment standardization

    NASA Astrophysics Data System (ADS)

    Maget, Vincent; Ecoffet, Robert; Roussel, Jean-Francois

    Ever since its creation in 1967, the Space Environment Department (DESP) at ONERA's objective has been to evaluate the environmental conditions of space missions and prevent the damage they may cause. The DESP studies and models the different components of the space mission environment (mainly charged particles) and evaluates the associated risks with on-board experiments and simulations on the ground. As the reference expert in space environment for both the French Space Agency and European space industries, the DESP has been named as the French representative in the ISO TC20 / SC14 / WG4 working group. In parallel to this contribution, the DESP is also involved in WG1 (Design engineering and production) and WG6 (Materials and Processes),as well as in the European Cooperation for Space Standardization (ECSS) committee dedicated to Space Environment standards (ECSS-10.04C). The purpose of this presentation is, first, to detail the ONERA’s contributions to space environment standardizations (its role as well as the standards developed at ONERA). In a second step, I shall also present some on-going works such as data assimilation and specifications model for other planets (Jupiter and Saturn) conducted at ONERA, in order to prepare the next generation standards and anticipate Space community needs.

  9. Physics of the Space Environment

    NASA Astrophysics Data System (ADS)

    Vasyliünas, Vytenis M.

    This book, one in the Cambridge Atmospheric and Space Science Series, joins a growing list of advanced-level textbooks in a field of study and research known under a variety of names: space plasma physics, solar-terrestrial or solar-planetary relations, space weather, or (the official name of the relevant AGU section) space physics and aeronomy. On the basis of graduate courses taught by the author in various departments at the University of Michigan, complete with problems and with appendices of physical constants and mathematical identities, this is indeed a textbook, systematic and severe in its approach. The book is divided into three parts, in length ratios of roughly 6:4:5. Part I, “Theoretical Description of Gases and Plasmas,” starts by writing down Maxwell's equations and the Lorentz transformation (no nonsense about any introductory material of a descriptive or historical nature) and proceeds through particle orbit theory, kinetics, and plasma physics with fluid and MHD approximations to waves, shocks, and energetic particle transport. Part II, “The Upper Atmosphere,” features chapters on the terrestrial upper atmosphere, airglow and aurora, and the ionosphere. Part III, “Sun-Earth Connection,” deals with the Sun, the solar wind, cosmic rays, and the terrestrial magnetosphere. The book thus covers, with two exceptions, just about all the topics of interest to Space Physics and Aeronomy scientists, and then some (the chapter on the Sun, for instance, briefly discusses also topics of the solar interior: thermonuclear energy generation, equilibrium structure, energy transfer, with a page or two on each). One exception reflects a strong geocentric bias: there is not one word in the main text on magnetospheres and ionospheres of other planets and their interaction with the solar wind (they are mentioned in a few problems). The other exception: the chapter on the terrestrial magnetosphere lacks a systematic exposition of the theory of

  10. The ESA Space Environment Information System (SPENVIS)

    NASA Astrophysics Data System (ADS)

    Heynderickx, D.; Quaghebeur, B.; Evans, H. D. R.

    2002-01-01

    The ESA SPace ENVironment Information System (SPENVIS) provides standardized access to models of the hazardous space environment through a user-friendly WWW interface. The interface includes parameter input with extensive defaulting, definition of user environments, streamlined production of results (both in graphical and textual form), background information, and on-line help. It is available on-line at http://www.spenvis.oma.be/spenvis/. SPENVIS Is designed to help spacecraft engineers perform rapid analyses of environmental problems and, with extensive documentation and tutorial information, allows engineers with relatively little familiarity with the models to produce reliable results. It has been developed in response to the increasing pressure for rapid-response tools for system engineering, especially in low-cost commercial and educational programmes. It is very useful in conjunction with radiation effects and electrostatic charging testing in the context of hardness assurance. SPENVIS is based on internationally recognized standard models and methods in many domains. It uses an ESA-developed orbit generator to produce orbital point files necessary for many different types of problem. It has various reporting and graphical utilities, and extensive help facilities. The SPENVIS radiation module features models of the proton and electron radiation belts, as well as solar energetic particle and cosmic ray models. The particle spectra serve as input to models of ionising dose (SHIELDOSE), Non-Ionising Energy Loss (NIEL), and Single Event Upsets (CREME). Material shielding is taken into account for all these models, either as a set of user-defined shielding thicknesses, or in combination with a sectoring analysis that produces a shielding distribution from a geometric description of the satellite system. A sequence of models, from orbit generator to folding dose curves with a shielding distribution, can be run as one process, which minimizes user interaction and

  11. Space shuttle natural environment analysis

    NASA Technical Reports Server (NTRS)

    Batts, Wade

    1988-01-01

    Five major tasks are briefly outlined: development of detailed wind profile measurements for Kennedy Space Center (KSC) and Vandenberg Air Force Base (VAFB): development of software to construct meteorological data tapes for use in the STS Post Ascent Analysis; development of storage, access, and utilization codes for Global Cloud Cover data; development of software and meteorological data bases to establish launch delay risks at KSC and VAFB; and development of the meteorological tower 301 climatological data base at VAFB.

  12. Space Environment and Effects System (SEES)

    NASA Astrophysics Data System (ADS)

    Higashio, Nana; Obara, Takahiro; Matsumoto, Haruhisa; Koga, Kiyokazu; Koshiishi, Hideki

    Space environment group in JAXA has installed insturments to measure space environment on eleven satellites. In the last year, the biggest instrument called SEDA-AP (Space Environment Data Acquision equipment -Attached Paylod) was atteched to the palette of JEM (ISS). On the other hand, we have a web site, "Space Environment and Effects System(SEES)". This system consisits of four parts. First part is to provide data that were obtained from these insturments. There are 18 kinds of mesurments, for example, radiation, magnetic field and so on. In 1994, Anik E-1 and Anik E-2 were broken by solar storm and we could catch the abnormal data from our instrument. Second part is a warning system. Many Japanese satellites are working around the earth and they are always exposed to radioactivity in space. So we predict the the radiation data in two days and if the expected value is over the threshold of safety, we inform a warning massage to users who want to keep their satellites safe. And we also provide the warning massage for Japanese astronauts who stay at ISS. Third part is the tool of the space environment /satellite environment models. There are 12 kinds of environment models which are constructed from 90 space environment models, for example, radiation model, solar activity model and so on. If you register your infomation in the SEES web site, you can simulate space environment by using them. Fourth part is providing the 2D and 3D infomations of satellite's orvits. This show the satelllite's position on the world map at a paticular time. If you want to use this system, please visit our SEES page at (http://seesproxy.tksc.jaxa.jp/fw/dfw/SEES/index.html ).

  13. Space environment robot vision system

    NASA Technical Reports Server (NTRS)

    Wood, H. John; Eichhorn, William L.

    1990-01-01

    A prototype twin-camera stereo vision system for autonomous robots has been developed at Goddard Space Flight Center. Standard charge coupled device (CCD) imagers are interfaced with commercial frame buffers and direct memory access to a computer. The overlapping portions of the images are analyzed using photogrammetric techniques to obtain information about the position and orientation of objects in the scene. The camera head consists of two 510 x 492 x 8-bit CCD cameras mounted on individually adjustable mounts. The 16 mm efl lenses are designed for minimum geometric distortion. The cameras can be rotated in the pitch, roll, and yaw (pan angle) directions with respect to their optical axes. Calibration routines have been developed which automatically determine the lens focal lengths and pan angle between the two cameras. The calibration utilizes observations of a calibration structure with known geometry. Test results show the precision attainable is plus or minus 0.8 mm in range at 2 m distance using a camera separation of 171 mm. To demonstrate a task needed on Space Station Freedom, a target structure with a movable I beam was built. The camera head can autonomously direct actuators to dock the I-beam to another one so that they could be bolted together.

  14. Natural Hazards of the Space Environment

    NASA Technical Reports Server (NTRS)

    Evans, Steven W.; Kross, Dennis A. (Technical Monitor)

    2000-01-01

    Spacecraft in Low Earth Orbit (LEO) are subject to numerous environmental hazards. Here I'll briefly discuss three environment factors that pose acute threats to the survival of spacecraft systems and crew: atmospheric drag, impacts by meteoroids and orbital debris, and ionizing radiation. Atmospheric drag continuously opposes the orbital motion of a satellite, causing the orbit to decay. This decay will lead to reentry if not countered by reboost maneuvers. Orbital debris is a by-product of man's activities in space, and consists of objects ranging in size from miniscule paint chips to spent rocket stages and dead satellites. Ionizing radiation experienced in LEO has several components: geomagnetically trapped protons and electrons (Van Allen belts); energetic solar particles; galactic cosmic rays; and albedo neutrons. These particles can have several types of prompt harmful effects on equipment and crew, from single-event upsets, latchup, and burnout of electronics, to lethal doses to crew.All three types of prompt threat show some dependence on the solar activity cycle. Atmospheric drag mitigation and large debris avoidance require propulsive maneuvers. M/OD and ionizing radiation require some form of shielding for crew and sensitive equipment. Limiting exposure time is a mitigation technique for ionizing radiation and meteor streams.

  15. Space Environments and Spacecraft Effects Organization Concept

    NASA Technical Reports Server (NTRS)

    Edwards, David L.; Burns, Howard D.; Miller, Sharon K.; Porter, Ron; Schneider, Todd A.; Spann, James F.; Xapsos, Michael

    2012-01-01

    The National Aeronautics and Space Administration (NASA) is embarking on a course to expand human presence beyond Low Earth Orbit (LEO) while also expanding its mission to explore the solar system. Destinations such as Near Earth Asteroids (NEA), Mars and its moons, and the outer planets are but a few of the mission targets. Each new destination presents an opportunity to increase our knowledge of the solar system and the unique environments for each mission target. NASA has multiple technical and science discipline areas specializing in specific space environments disciplines that will help serve to enable these missions. To complement these existing discipline areas, a concept is presented focusing on the development of a space environments and spacecraft effects (SENSE) organization. This SENSE organization includes disciplines such as space climate, space weather, natural and induced space environments, effects on spacecraft materials and systems and the transition of research information into application. This space environment and spacecraft effects organization will be composed of Technical Working Groups (TWG). These technical working groups will survey customers and users, generate products, and provide knowledge supporting four functional areas: design environments, engineering effects, operational support, and programmatic support. The four functional areas align with phases in the program mission lifecycle and are briefly described below. Design environments are used primarily in the mission concept and design phases of a program. Engineering effects focuses on the material, component, sub-system and system-level selection and the testing to verify design and operational performance. Operational support provides products based on real time or near real time space weather to mission operators to aid in real time and near-term decision-making. The programmatic support function maintains an interface with the numerous programs within NASA, other federal

  16. The Near-Earth Space Radiation Environment

    NASA Technical Reports Server (NTRS)

    Xapsos, Michael

    2008-01-01

    This viewgraph presentation reviews the effects of the Near-Earth space radiation environment on NASA missions. Included in this presentation is a review of The Earth s Trapped Radiation Environment, Solar Particle Events, Galactic Cosmic Rays and Comparison to Accelerator Facilities.

  17. Space environments and their effects on space automation and robotics

    NASA Technical Reports Server (NTRS)

    Garrett, Henry B.

    1990-01-01

    Automated and robotic systems will be exposed to a variety of environmental anomalies as a result of adverse interactions with the space environment. As an example, the coupling of electrical transients into control systems, due to EMI from plasma interactions and solar array arcing, may cause spurious commands that could be difficult to detect and correct in time to prevent damage during critical operations. Spacecraft glow and space debris could introduce false imaging information into optical sensor systems. The presentation provides a brief overview of the primary environments (plasma, neutral atmosphere, magnetic and electric fields, and solid particulates) that cause such adverse interactions. The descriptions, while brief, are intended to provide a basis for the other papers presented at this conference which detail the key interactions with automated and robotic systems. Given the growing complexity and sensitivity of automated and robotic space systems, an understanding of adverse space environments will be crucial to mitigating their effects.

  18. Space, Atmospheric, and Terrestrial Radiation Environments

    NASA Technical Reports Server (NTRS)

    Barth, Janet L.; Dyer, C. S.; Stassinopoulos, E. G.

    2003-01-01

    The progress on developing models of the radiation environment since the 1960s is reviewed with emphasis on models that can be applied to predicting the performance of microelectronics used in spacecraft and instruments. Space, atmospheric, and ground environments are included. It is shown that models must be adapted continually to account for increased understanding of the dynamics of the radiation environment and the changes in microelectronics technology. The IEEE Nuclear and Space Radiation Effects Conference is a vital forum to report model progress to the radiation effects research community.

  19. Space Ethics and Protection of the Space Environment

    NASA Astrophysics Data System (ADS)

    Williamson, Mark

    2002-01-01

    The construction of the International Space Station in low Earth orbit and the formulation of plans to search for life on Mars - one day by means of manned missions - indicate that mankind is intent on making the space environment part of its domain. Publicity surrounding space tourism, in-space `burials' and the sale of lunar `real estate' suggests that, some time in the 21st century, the space environment will become an extraterrestrial extension of our current business and domestic environment. This prompts the question of our collective attitude towards the space environment and the degree to which we should regulate its use and protect it for future generations. What, indeed, are the ethical considerations of space exploration and development? Ethics can be defined as "the philosophical study of the moral value of human conduct, and of the rules or principles that ought to govern it". More practically, it represents "an approved code of behaviour" adopted, for example, by a group or profession. If a set of ethics is to be developed for space, it is important that what we refer to as the `space community', or `space profession', is intimately involved. Indeed, if it is not, the profession risks having the job done for it, for example by politicians and members of the general public, who for their own reasons may wish to place restrictions on space development, or ban it altogether. The terrestrial nuclear power industry, for example, has already suffered this fate, while widespread ignorance of the subject has led to a moratorium on the use of RTGs in spacecraft. However, there is a danger in the discussion of ethics that consideration is confined to the philosophical aspects, thus excusing those involved from providing practical solutions to the problems that emerge. The fact that mankind has already affected, and arguably damaged, the space environment transports the discussion beyond the philosophical realm. This paper offers a pragmatic analysis of one

  20. Secondary Electron Emission and the Exploration of Space

    NASA Technical Reports Server (NTRS)

    Minow, Joseph I.

    2006-01-01

    The emission of secondary electrons from surfaces exposed to the space plasma and radiation environment is a process of great importance to space system engineering design and operations. A spacecraft will collect charge until it reaches an equilibrium potential gov,erned by the balance of incoming electron and ion currents from the space environment with outgoing secondary, backscattered, and photoelectron currents. Laboratory measurements of secondary electron yields are an important parameter for use in spacecraft charging analyses because the magnitude and sign of the equilibrium potential depends on both the energy spectrum of electrons and ions in the space environment and the electrical properties of the surface materials (including the energy dependent secondary electron yields). Typical benign equilibrium potentials range &om a few tens of volts positive in interplanetary space to a few volts negative in low Earth orbit. However, spacecraft are known to charge to negative potentials exceeding one to ten kilovolts in some environments and anomalies or system failures due to electrostatic discharges originating from highly charged surfaces becomes a serious concern. This presentation will provide a review of the spacecraft charging process with special emphasis on the role of secondary electrons in controlling the current balance process. Charging examples will include spacecraft in Earth orbit and interplanetary space as well as dust charging on the lunar surface, a phenomenon of importance to future lunar surface operations.

  1. Interpreting the International Space Station Microgravity Environment

    NASA Technical Reports Server (NTRS)

    DeLombard, Richard; Hrovat, Kenneth; Kelly, Eric M.; Humphreys, Brad

    2005-01-01

    The International Space Station (ISS) serves as a platform for microgravity research for the foreseeable future. A microgravity environment is one in which the effects of gravity are drastically reduced which then allows physical experiments to be conducted without the overpowering effects of gravity. A physical environment with very low-levels of acceleration and vibration has been accomplished by both the free fall associated with orbital flight and the design of the International Space Station. The International Space Station design has been driven by a long-standing, high-level requirement for a microgravity mode of operation. The Space Acceleration Measurement System has been in operation for nearly four years on the ISS measuring the microgravity environment in support of principal investigators and to characterize the ISS microgravity environment. The Principal Investigator Microgravity Services project functions as a detective to ascertain the source of disturbances seen in the ISS microgravity environment to allow correlation between that environment and experimental data. Payload developers need to predict the microgravity environment that will be imposed upon an experiment and ensure that the science and engineering requirements will be met. The Principal Investigator Microgravity Services project is developing n interactive tool to predict the microgravity environment at science payloads based on user defined operational scenarios. These operations (predictions and post-analyses) allow a researcher to examine the microgravity acceleration levels expected to exist when their experiment is operated and then receive an analysis of the environment which existed during their experiment operations. Presented in this paper will be descriptions of the environment predictive tool and an investigation into a previously unknown disturbance in the ISS microgravity environment.

  2. Microgravity Environment on the International Space Station

    NASA Technical Reports Server (NTRS)

    DeLombard, Richard; Hrovat, Kenneth; Kelly, Eric; McPherson, Kevin

    2004-01-01

    A primary feature of the International Space Station will be its microgravity environment--an environment in which the effects of gravity are drastically reduced. The International Space Station design has been driven by a long-standing, high-level requirement for a microgravity mode of operation. Various types of data are gathered when science experiments are conducted. The acceleration levels experienced during experiment operation should be factored into the analysis of the results of most microgravity experiments. To this end, the Space Acceleration Measurement System records the acceleration levels to support microgravity researchers for nearly three years of International Space Station operations. The Principal Investigator Microgravity Services project assists the experiments principal investigators with their analysis of the acceleration (microgravity) environment. The Principal Investigator Microgravity Services project provides cataloged data, periodic analysis summary reports, specialized reports for experiment teams, and real-time data in a variety of user-defined formats. Characterization of the various microgravity carriers (e.g., Shuttle and International Space Station) is also accomplished for the experiment teams. Presented in this paper will be a short description of how microgravity disturbances may affect some experiment classes, a snapshot of the microgravity environment, and a view into how well the space station is expected to meet the user requirements.

  3. Phase-space foundations of electron holography

    NASA Astrophysics Data System (ADS)

    Lubk, A.; Röder, F.

    2015-09-01

    We present a unified formalism for describing various forms of electron holography in quantum mechanical phase space including their extensions to quantum-state reconstructions. The phase-space perspective allows for taking into account partial coherence as well as the quantum mechanical detection process typically hampering the unique reconstruction of a wave function. We elaborate on the limitations imposed by the electron optical elements of the transmission electron microscope as well as the scattering at the target. The results provide the basis for vastly extending the scope of electron holographic techniques towards analyzing partially coherent signals such as inelastically scattered electrons or electron pulses used in ultrafast transmission electron microscopy.

  4. International Space Station External Contamination Environment for Space Science Utilization

    NASA Technical Reports Server (NTRS)

    Soares, Carlos E.; Mikatarian, Ronald R.; Steagall, Courtney A.; Huang, Alvin Y.; Koontz, Steven; Worthy, Erica

    2014-01-01

    The International Space Station (ISS) is the largest and most complex on-orbit platform for space science utilization in low Earth orbit. Multiple sites for external payloads, with exposure to the associated natural and induced environments, are available to support a variety of space science utilization objectives. Contamination is one of the induced environments that can impact performance, mission success and science utilization on the vehicle. The ISS has been designed, built and integrated with strict contamination requirements to provide low levels of induced contamination on external payload assets. This paper addresses the ISS induced contamination environment at attached payload sites, both at the requirements level as well as measurements made on returned hardware, and contamination forecasting maps being generated to support external payload topology studies and science utilization.

  5. Stress proteins are induced by space environment

    NASA Astrophysics Data System (ADS)

    Takahashi, Akihisa; Ohnishi, Takeo

    The space environment contains two major biologically significant influences such as space radiations and microgravity. Almost all organisms possess essential recognition and response systems for environmental changes. The famous one of cellular stress responses is the gene induction of heat shock protein (HSP). HSP expression is increased under elevated temperatures, and also increased by other sources of cellular stress, including ionizing radiation, oxidative injury, osmotic stress and the unfolded protein response. HSPs assist in the folding and maintenance of newly translated proteins, the refolding of denatured proteins and the further unfolding of misfolded or destabilized proteins to protect the cell from crisis. Based on our space experiment, we report the results and discussion from the viewpoint of HSP expression after exposure to space environment.

  6. Space Station - The base for tomorrow's electronic industry

    NASA Technical Reports Server (NTRS)

    Naumann, Robert J.

    1985-01-01

    The potential value of space material processing on the Space Station for the electronics industry is examined. The primary advantages of the space environment for producing high-purity semiconductors and electrooptical materials are identified as the virtual absence of gravity (suppressing buoyancy-driven convection in melts and density segregation of alloys) and the availabilty of high vacuum (with high pumping speed and heat rejection). The recent history of material development and processing technology in the electronics industry is reviewed, and the principal features of early space experiments are outlined.

  7. Space Station Freedom natural environment design models

    NASA Technical Reports Server (NTRS)

    Suggs, Robert M.

    1993-01-01

    The Space Station Freedom program has established a series of natural environment models and databases for utilization in design and operations planning activities. The suite of models and databases that have either been selected from among internationally recognized standards or developed specifically for spacecraft design applications are presented. The models have been integrated with an orbit propagator and employed to compute environmental conditions for planned operations altitudes of Space Station Freedom.

  8. Space Weather Operational Products in the NOAA Space Environment Center

    NASA Astrophysics Data System (ADS)

    Murtagh, W. J.; Onsager, T. G.

    2006-12-01

    The NOAA Space Environment Center (SEC) is the Nation's official source of space weather alerts and warnings, and provides real-time monitoring and forecasting of solar and geophysical events. The SEC, a 24- hour/day operations center, provides space weather products to the scientific and user communities in the United States and around the world. This presentation will provide a brief overview of the SEC current suite of space weather products, with an emphasis on models and products recently introduced into the Operations Center. Customer uses of products will be discussed, which will highlight the diverse customer base for space weather services. Also, models in SEC's testbed will be introduced. SEC's testbed facility is dedicated to moving space environment models from a research-development mode to an operational mode. The status of efforts to replace NASA's aging real-time monitor (ACE) in the solar wind ahead of Earth, an "upstream data buoy", will also be described. Numerous existing and planned space weather products and models rely on near real-time solar wind data.

  9. Acceleration Environment of the International Space Station

    NASA Technical Reports Server (NTRS)

    McPherson, Kevin; Kelly, Eric; Keller, Jennifer

    2009-01-01

    Measurement of the microgravity acceleration environment on the International Space Station has been accomplished by two accelerometer systems since 2001. The Microgravity Acceleration Measurement System records the quasi-steady microgravity environment, including the influences of aerodynamic drag, vehicle rotation, and venting effects. Measurement of the vibratory/transient regime, comprised of vehicle, crew, and equipment disturbances, has been accomplished by the Space Acceleration Measurement System-II. Until the arrival of the Columbus Orbital Facility and the Japanese Experiment Module, the location of these sensors, and therefore, the measurement of the microgravity acceleration environment, has been limited to within the United States Laboratory. Japanese Aerospace Exploration Agency has developed a vibratory acceleration measurement system called the Microgravity Measurement Apparatus which will be deployed within the Japanese Experiment Module to make distributed measurements of the Japanese Experiment Module's vibratory acceleration environment. Two Space Acceleration Measurement System sensors from the United States Laboratory will be re-deployed to support vibratory acceleration data measurement within the Columbus Orbital Facility. The additional measurement opportunities resulting from the arrival of these new laboratories allows Principal Investigators with facilities located in these International Space Station research laboratories to obtain microgravity acceleration data in support of their sensitive experiments. The Principal Investigator Microgravity Services project, at NASA Glenn Research Center, in Cleveland, Ohio, has supported acceleration measurement systems and the microgravity scientific community through the processing, characterization, distribution, and archival of the microgravity acceleration data obtained from the International Space Station acceleration measurement systems. This paper summarizes the PIMS capabilities available

  10. Book Review: Physics of the Space Environment

    NASA Technical Reports Server (NTRS)

    Holman, Gordon D.

    1998-01-01

    Space physics, narrowly defined as the study of Earth's plasma environment, has had an identity crisis throughout its relatively brief existence as a discipline. - The limited and often serendipitous nature of the data requires the research style of an astrophysicist. However, the in situ observations and instrumentation that are central to the field are quite different from the remote observations and instrumentation of astronomy. Compared to neutral gases, the wealth of additional phenomena and the complexity associated with magnetized plasmas and their interaction leaves little in common with the atmospheric scientist. Although the phenomena studied in space physics are ultimately important to astrophysics, the intimate measurements of plasma properties provide a greater commonality with the plasma physicist. Space physics has experienced something of a renaissance in the past few years. The interdisciplinary umbrella "Solar-Terrestrial Physics" or "Sun-Earth Connection" has stimulated an increasing interaction of space physicists, solar physicists and atmospheric scientists. Spectacular images of the Sun from Yohkoh and SOHO and solar-activity-related damage to communications satellites have increased the public's awareness of and interest in "space weather". The dangers of energetic particles and currents in space to technological systems and to future space exploration have elevated space physics observations from interesting scientific measurements that can be included on a space probe to critically important measurements that must be made.

  11. Learning Spaces in Mobile Learning Environments

    ERIC Educational Resources Information Center

    Solvberg, Astrid M.; Rismark, Marit

    2012-01-01

    Mobile learning (m-learning) environments open a wide range of new and exciting learning opportunities, and envision students who are continually on the move, learn across space and time, and move from topic to topic and in and out of interaction with technology. In this article we present findings from a study of how students manoeuvre and study…

  12. Predictions of the Space Environment Services Center

    NASA Technical Reports Server (NTRS)

    Heckman, G. R.

    1979-01-01

    The types of users of the Space Environment Services Center are identified. All the data collected by the Center are listed and a short description of each primary index or activity summary is given. Each type of regularly produced forecast is described, along with the methods used to produce each prediction.

  13. Space weather at different planetary environments

    NASA Astrophysics Data System (ADS)

    Plainaki, Christina; Milillo, Anna; Andriopoulou, Maria; Dandouras, Iannis; Radioti, Aikaterini; Lilensten, Jean; Coustenis, Athena; Nordheim, Tom; Orsini, Stefano; Mura, Alessandro; Mangano, Valeria

    2015-04-01

    Different aspects of the conditions in the Sun, solar wind and magnetospheric plasmas, at various planetary systems of our Solar System, can influence the performance and reliability of space-borne technological systems. The science study of the so-called Planetary Space Weather considers different cross-disciplinary issues, including: - the interaction of solar wind/magnetospheric plasmas with planetary/satellite surfaces, ionospheres and thick (e.g. at Jupiter, Saturn, Uranus, Mars, Venus, Titan) or tenuous (e.g. Ganymede, Europa, Mercury, our Moon) atmospheres, including the generation of auroras - the satellite interactions with their neutral environments and dust - the variability of the magnetospheric regions under different solar wind conditions - radiation belts, and their interactions with atmospheres/satellites/rings, in different planetary environments - the inter-comparisons of space weather conditions in different planetary environments In this paper, a brief review of theoretical and data analysis studies regarding planetary space weather in different bodies of our Solar System is presented. The importance of such studies for the in-situ data interpretations as well as for the preparation of future space missions is outlined.

  14. Space Environment's Effects on Seal Materials

    NASA Technical Reports Server (NTRS)

    deGroh, Henry C., III; Daniels, Christopher C.; Dunlap, Patrick; Miller, Sharon; Dever, Joyce; Waters, Deborah; Steinetz, Bruce M.

    2007-01-01

    A Low Impact Docking System (LIDS) is being developed by the NASA Johnson Space Center to support future missions of the Crew Exploration Vehicle (CEV). The LIDS is androgynous, such that each system half is identical, thus any two vehicles or modules with LIDS can be coupled. Since each system half is a replica, the main interface seals must seal against each other instead of a conventional flat metal surface. These sealing surfaces are also expected to be exposed to the space environment when vehicles are not docked. The NASA Glenn Research Center (NASA GRC) is supporting this project by developing the main interface seals for the LIDS and determining the durability of candidate seal materials in the space environment. In space, the seals will be exposed to temperatures of between 50 to 50 C, vacuum, atomic oxygen, particle and ultraviolet radiation, and micrometeoroid and orbital debris (MMOD). NASA GRC is presently engaged in determining the effects of these environments on our candidate elastomers. Since silicone rubber is the only class of seal elastomer that functions across the expected temperature range, NASA GRC is focusing on three silicone elastomers: two provided by Parker Hannifin (S0-899-50 and S0-383-70) and one from Esterline Kirkhill (ELA-SA-401). Our results from compression set, elastomer to elastomer adhesion, and seal leakage tests before and after various simulated space exposures will be presented.

  15. Momentum-space properties from coordinate-space electron density

    SciTech Connect

    Harbola, Manoj K.; Zope, Rajendra R.; Kshirsagar, Anjali; Pathak, Rajeev K.

    2005-05-22

    Electron density and electron momentum density, while independently tractable experimentally, bear no direct connection without going through the many-electron wave function. However, invoking a variant of the constrained-search formulation of density-functional theory, we develop a general scheme (valid for arbitrary external potentials) yielding decent momentum-space properties, starting exclusively from the coordinate-space electron density. A numerical illustration of the scheme is provided for the closed-shell atomic systems He, Be, and Ne in their ground state and for 1s{sup 1} 2s{sup 1} singlet electronic excited state for helium by calculating the Compton profiles and the expectation values derived from given coordinate-space electron densities.

  16. Deep Space Design Environments for Human Exploration

    NASA Technical Reports Server (NTRS)

    Wilson, J. W.; Clowdsley, M. S.; Cucinotta, F. A.; Tripathi, R. K.; Nealy, J. E.; DeAngelis, G.

    2002-01-01

    Mission scenarios outside the Earth's protective magnetic shield are being studied. Included are high usage assets in the near-Earth environment for casual trips, for research, and for commercial/operational platforms, in which career exposures will be multi-mission determined over the astronaut's lifetime. The operational platforms will serve as launching points for deep space exploration missions, characterized by a single long-duration mission during the astronaut's career. The exploration beyond these operational platforms will include missions to planets, asteroids, and planetary satellites. The interplanetary environment is evaluated using convective diffusion theory. Local environments for each celestial body are modeled by using results from the most recent targeted spacecraft, and integrated into the design environments. Design scenarios are then evaluated for these missions. The underlying assumptions in arriving at the model environments and their impact on mission exposures within various shield materials will be discussed.

  17. Deep space environments for human exploration

    NASA Technical Reports Server (NTRS)

    Wilson, J. W.; Clowdsley, M. S.; Cucinotta, F. A.; Tripathi, R. K.; Nealy, J. E.; De Angelis, G.

    2004-01-01

    Mission scenarios outside the Earth's protective magnetic shield are being studied. Included are high usage assets in the near-Earth environment for casual trips, for research, and for commercial/operational platforms, in which career exposures will be multi-mission determined over the astronaut's lifetime. The operational platforms will serve as launching points for deep space exploration missions, characterized by a single long-duration mission during the astronaut's career. The exploration beyond these operational platforms will include missions to planets, asteroids, and planetary satellites. The interplanetary environment is evaluated using convective diffusion theory. Local environments for each celestial body are modeled by using results from the most recent targeted spacecraft, and integrated into the design environments. Design scenarios are then evaluated for these missions. The underlying assumptions in arriving at the model environments and their impact on mission exposures within various shield materials will be discussed. Published by Elsevier Ltd on behalf of COSPAR.

  18. Deep space environments for human exploration.

    PubMed

    Wilson, J W; Clowdsley, M S; Cucinotta, F A; Tripathi, R K; Nealy, J E; De Angelis, G

    2004-01-01

    Mission scenarios outside the Earth's protective magnetic shield are being studied. Included are high usage assets in the near-Earth environment for casual trips, for research, and for commercial/operational platforms, in which career exposures will be multi-mission determined over the astronaut's lifetime. The operational platforms will serve as launching points for deep space exploration missions, characterized by a single long-duration mission during the astronaut's career. The exploration beyond these operational platforms will include missions to planets, asteroids, and planetary satellites. The interplanetary environment is evaluated using convective diffusion theory. Local environments for each celestial body are modeled by using results from the most recent targeted spacecraft, and integrated into the design environments. Design scenarios are then evaluated for these missions. The underlying assumptions in arriving at the model environments and their impact on mission exposures within various shield materials will be discussed. PMID:15880915

  19. Space Weathering in the Mercurian Environment

    NASA Technical Reports Server (NTRS)

    Noble, S. K.; Pieters, C. M.

    2001-01-01

    Space weathering processes are known to be important on the Moon. These processes both create the lunar regolith and alter its optical properties. Like the Moon, Mercury has no atmosphere to protect it from the harsh space environment and therefore it is expected that it will also incur the effects of space weathering. However, there are many important differences between the environments of Mercury and the Moon. These environmental differences will almost certainly affect the weathering processes and the products of those processes. It should be possible to observe the effects of these differences in Vis (visible)/NIR (near infrared) spectra of the type expected to be returned by MESSENGER. More importantly, understanding these weathering processes and their consequences is essential for evaluating the spectral data returned from MESSENGER and other missions in order to determine the mineralogy and the Fe content of the Mercurian surface. Additional information is contained in the original extended abstract.

  20. Lead-Free Experiment in a Space Environment

    NASA Technical Reports Server (NTRS)

    Blanche, J. F.; Strickland, S. M.

    2012-01-01

    This Technical Memorandum addresses the Lead-Free Technology Experiment in Space Environment that flew as part of the seventh Materials International Space Station Experiment outside the International Space Station for approximately 18 months. Its intent was to provide data on the performance of lead-free electronics in an actual space environment. Its postflight condition is compared to the preflight condition as well as to the condition of an identical package operating in parallel in the laboratory. Some tin whisker growth was seen on a flight board but the whiskers were few and short. There were no solder joint failures, no tin pest formation, and no significant intermetallic compound formation or growth on either the flight or ground units.

  1. Reliability of Electronics for Cryogenic Space Applications Being Assessed

    NASA Technical Reports Server (NTRS)

    Patterson, Richard L.; Hammoud, Ahmad

    2005-01-01

    Many future NASA missions will require electronic parts and circuits that can operate reliably and efficiently in extreme temperature environments below typical device specification temperatures. These missions include the Mars Exploration Laboratory, the James Webb Space Telescope, the Europa Orbiter, surface rovers, and deep-space probes. In addition to NASA, the aerospace and commercial sectors require cryogenic electronics in applications that include advanced satellites, military hardware, medical instrumentation, magnetic levitation, superconducting energy management and distribution, particle confinement and acceleration, and arctic missions. Besides surviving hostile space environments, electronics capable of low-temperature operation would enhance circuit performance, improve system reliability, extend lifetime, and reduce development and launch costs. In addition, cryogenic electronics are expected to result in more efficient systems than those at room temperature.

  2. Space environment's effect on MODIS calibration

    NASA Astrophysics Data System (ADS)

    Dodd, J. L.; Wenny, B. N.; Chiang, K.; Xiong, X.

    2010-09-01

    The MODerate resolution Imaging Spectroradiometer flies on board the Earth Observing System (EOS) satellites Terra and Aqua in a sun-synchronous orbit that crosses the equator at 10:30 AM and 2:30 PM, respectively, at a low earth orbit (LEO) altitude of 705 km. Terra was launched on December 18,1999 and Aqua was launched on May 4, 2002. As the MODIS instruments on board these satellites continue to operate beyond the design lifetime of six years, the cumulative effect of the space environment on MODIS and its calibration is of increasing importance. There are several aspects of the space environment that impact both the top of atmosphere (TOA) calibration and, therefore, the final science products of MODIS. The south Atlantic anomaly (SAA), spacecraft drag, extreme radiative and thermal environment, and the presence of orbital debris have the potential to significantly impact both MODIS and the spacecraft, either directly or indirectly, possibly resulting in data loss. Efforts from the Terra and Aqua Flight Operations Teams (FOT), the MODIS Instrument Operations Team (IOT), and the MODIS Characterization Support Team (MCST) prevent or minimize external impact on the TOA calibrated data. This paper discusses specific effects of the space environment on MODIS and how they are minimized.

  3. Space Vehicle Terrestrial Environment Design Requirements Guidelines

    NASA Technical Reports Server (NTRS)

    Johnson, Dale L.; Keller, Vernon W.; Vaughan, William W.

    2006-01-01

    The terrestrial environment is an important driver of space vehicle structural, control, and thermal system design. NASA is currently in the process of producing an update to an earlier Terrestrial Environment Guidelines for Aerospace Vehicle Design and Development Handbook. This paper addresses the contents of this updated handbook, with special emphasis on new material being included in the areas of atmospheric thermodynamic models, wind dynamics, atmospheric composition, atmospheric electricity, cloud phenomena, atmospheric extremes, and sea state. In addition, the respective engineering design elements are discussed relative to terrestrial environment inputs that require consideration. Specific lessons learned that have contributed to the advancements made in the application and awareness of terrestrial environment inputs for aerospace engineering applications are presented.

  4. NASA's Space Environments and Effects (SEE) Program: The Pursuit of Tomorrow's Space Technology

    NASA Technical Reports Server (NTRS)

    Pearson, Steven D.; Hardage, Donna M.

    1998-01-01

    A hazard to all spacecraft orbiting the earth and exploring the unknown in deep space is the existence of a harsh and ever changing environment with its subsequent effects. Some of these environmental hazards, such as plasma, extreme thermal excursions, meteoroids, and ionizing radiation result from natural sources, whereas others, such as orbital debris and neutral contamination are induced by the presence of spacecraft themselves. The subsequent effects can provide damaging or even disabling effects on spacecraft, its materials, and its instruments. In partnership with industry, academia, and other government agencies, National Aeronautics & Space Administration's (NASA's) Space Environments & Effects (SEE) Program defines the space environments and advocates technology development to accommodate or mitigate these harmful environments on the spacecraft. This program provides a very comprehensive and focused approach to understanding the space environment, to define the best techniques for both flight and ground-based experimentation, to update the models which predict both the environments and the environmental effects on spacecraft, and finally to ensure that this information is properly maintained and inserted into spacecraft design programs. This paper will provide an overview of the Program's purpose, goals, database management and technical activities. In particular, the SEE Program has been very active in developing improved ionizing radiation models and developing related flight experiments which should aid in determining the effect of the radiation environment on modern electronics.

  5. Natural environment design requirements for the Space Telescope (revision A)

    NASA Technical Reports Server (NTRS)

    West, G. S.; Wright, J. J.

    1976-01-01

    The natural environment design requirements for the Space Telescope are presented. Because the Space Telescope is to be carried as cargo to orbital altitudes in the space shuttle bay, orbital environment impacts are the main concern.

  6. Natural environment design requirements for the space telescope

    NASA Technical Reports Server (NTRS)

    West, G. S.; Wright, J. J.

    1976-01-01

    The natural environment design requirements for the Large Space Telescope are presented. Because the Large Space Telescope is to be carried as cargo to orbital altitudes in the space shuttle bay, orbital environment impacts are emphasized.

  7. Droplet Charging Effects in the Space Environment

    SciTech Connect

    Joslyn, Thomas B.; Ketsdever, Andrew D.

    2011-05-20

    Several applications exist for transiting liquid droplets through the near-Earth space environment. Numerical results are presented for the charging of liquid droplets of trimethyl pentaphenyl siloxane (DC705) in three different plasma environments: ionosphere, auroral, and geosynchronous Earth orbit (GEO). Nominal and high geomagnetic activity cases are investigated. In general, high levels of droplet charging (>100 V) exist only in GEO during periods of high geomagnetic or solar activity. An experiment was conducted to assess the charging of silicon-oil droplets due to photoemission. The photoemission yield in the 120-200 nm wavelength range was found to be approximately 0.06.

  8. Electronic structure calculations in arbitrary electrostatic environments

    NASA Astrophysics Data System (ADS)

    Watson, Mark A.; Rappoport, Dmitrij; Lee, Elizabeth M. Y.; Olivares-Amaya, Roberto; Aspuru-Guzik, Alán

    2012-01-01

    Modeling of electronic structure of molecules in electrostatic environments is of considerable relevance for surface-enhanced spectroscopy and molecular electronics. We have developed and implemented a novel approach to the molecular electronic structure in arbitrary electrostatic environments that is compatible with standard quantum chemical methods and can be applied to medium-sized and large molecules. The scheme denoted CheESE (chemistry in electrostatic environments) is based on the description of molecular electronic structure subject to a boundary condition on the system/environment interface. Thus, it is particularly suited to study molecules on metallic surfaces. The proposed model is capable of describing both electrostatic effects near nanostructured metallic surfaces and image-charge effects. We present an implementation of the CheESE model as a library module and show example applications to neutral and negatively charged molecules.

  9. Space Analogue Environments: Are the Populations Comparable?

    NASA Astrophysics Data System (ADS)

    Sandal, G. M.

    Background: Much of our present understanding about psychology in space is based on studies of groups operating in so-called analogue environments where personnel are exposed to many of the same stressors as those experienced by astronauts in space. One possible problem with extrapolating results is that personnel operating in various hazardous and confined environments might differ in characteristics influencing coping, interaction, and performance. The object of this study was to compare the psychological similarity of these populations in order to get a better understanding of whether this extrapolation is justifiable. The samples investigated include polar crossings (N= 22), personnel on Antarctic research stations (N= 183), several military occupations (N= 187), and participants in space simulation studies (N=20). Methods: Personnel in each of these environments were assessed using the Personality Characteristic Inventory (PCI) and Utrecht Coping List (UCL). The PCI is a multidimensional trait assessment battery that measures various aspects of achievement orientation and social competence. The UCL is a questionnaire designed to assess habitual coping strategies when encountering stressful or demanding situations. Results: Only minor differences in use of habitual coping strategies were evident across the different samples. In relation to personality scores, the military subjects and participants in space simulation studies indicated higher competitiveness and negative instrumentality compared to both the personnel on Antarctic research stations and participants in polar expedition. Among the personnel on Antarctic research stations, significant gender differences were found with women scoring lower on competitiveness, negative instrumentality and impatience/irritability. Compared to the other samples, the participants in polar expeditions were found to be more homogeneous in personality and no significant gender differences were evident on the traits that

  10. Monitoring tropical environments with Space Shuttle photography

    NASA Technical Reports Server (NTRS)

    Helfert, Michael R.; Lulla, Kamlesh P.

    1989-01-01

    Orbital photography from the Space Shuttle missions (1981-88) and earlier manned spaceflight programs (1962-1975) allows remote sensing time series to be constructed for observations of environmental change in selected portions of the global tropics. Particular topics and regions include deforestation, soil erosion, supersedimentation in streams, lacustrine, and estuarine environments, and desertification in the greater Amazon, tropical Africa and Madagascar, South and Southeast Asia, and the Indo-Pacific archipelagoes.

  11. Potentially improved glasses from space environment

    NASA Technical Reports Server (NTRS)

    Nichols, R.

    1977-01-01

    The benefits of processing glasses in a low-gravity space environment are examined. Containerless processing, the absence of gravity driven convection, and lack of sedimentation are seen as potential advantages. Potential applications include the formation of glass-ceramics with a high content of active elements for ferromagnetic devices, the production of ultrapure chalcogenide glasses for laser windows and IR fiber optics, and improved glass products for use in optical systems and laser fusion targets.

  12. Microbial survival in deep space environment.

    NASA Technical Reports Server (NTRS)

    Silverman, G. J.

    1971-01-01

    Review of the knowledge available on the extent to which microorganisms (mainly microbial spores, vegetative cells, and fungi) are capable of surviving the environment of deep space, based on recent simulation experiments of deep space. A description of the experimental procedures used is followed by a discussion of deep space ecology, the behavior of microorganisms in ultrahigh vacuum, and factors influencing microbial survival. It is concluded that, so far, simulation experiments have proved far less lethal to microorganisms than to other forms of life. There are, however, wide gaps in the knowledge available, and no accurate predictions can as yet be made on the degree of lethality that might be incurred by a microbial population on a given mission. Therefore, sterilization of spacecraft surfaces is deemed necessary if induced panspermia (i.e., interplanetary life propagation) is to be avoided.

  13. Electronic Verification at the Kennedy Space Center

    NASA Technical Reports Server (NTRS)

    Johnson, T. W.

    1995-01-01

    This document reviews some current applications of Electronic Verification and the benefits such applications are providing the Kennedy Space Center (KSC). It also previews some new technologies, including statistics regarding performance and possible utilization of the technology.

  14. Particulate electron beam weld emission hazards in space

    NASA Technical Reports Server (NTRS)

    Bunton, Patrick H.

    1996-01-01

    The electron-beam welding process is well adapted to function in the environment of space. The Soviets were the first to demonstrate welding in space in the mid-1980's. Under the auspices of the International Space Welding Experiment (ISWE), an on-orbit test of a Ukrainian designed electron-beam welder (the Universal Hand Tool or 'UHT') is scheduled for October of 1997. The potential for sustained presence in space with the development of the international space station raises the possibility of the need for construction and repair in space. While welding is not scheduled to be used in the assembly of the space station, repair of damage from orbiting debris or meteorites is a potential need. Furthermore, safe and successful welding in the space environment may open new avenues for design and construction. The safety issue has been raised with regard to hot particle emissions (spatter) sometimes observed from the weld during operations. On earth the hot particles pose no particular hazard, but in space there exists the possibility for burn-through of the space suit which could be potentially lethal. Contamination of the payload bay by emitted particles could also be a problem.

  15. Space processing of electronic materials

    NASA Technical Reports Server (NTRS)

    Holland, L. R.

    1982-01-01

    The bulk growth of solid solution alloys of mercury telluride and cadmium telluride is discussed. These alloys are usually described by the formula Hg1-xCdxTe, and are useful for the construction of infrared detectors. The electronic energy band gap can be controlled between zero and 1.6 electron volts by adjusting the composition x. The most useful materials are at x approximately 20%, suitable for detection wavelengths of about 10 micrometers. The problems of growing large crystals are rooted in the wide phase diagram of the HgTe-CdTe pseudobinary system which leads to exaggerate segregation in freezing, constitutional supercooling, and other difficulties, and in the high vapor pressure of mercury at the growth temperatures, which leads to loss of stoichiometry and to the necessity of working in strong, pressure resistant sealed containers.

  16. Space weather circulation model of plasma clouds as background radiation medium of space environment.

    NASA Astrophysics Data System (ADS)

    Kalu, A. E.

    A model for Space Weather (SW) Circulation with Plasma Clouds as background radiation medium of Space Environment has been proposed and discussed. Major characteristics of the model are outlined and the model assumes a baroclinic Space Environment in view of observed pronounced horizontal electron temperature gradient with prevailing weak vertical temperature gradient. The primary objective of the study is to be able to monitor and realistically predict on real- or near real-time SW and Space Storms (SWS) affecting human economic systems on Earth as well as the safety and Physiologic comfort of human payload in Space Environment in relation to planned increase in human space flights especially with reference to the ISS Space Shuttle Taxi (ISST) Programme and other prolonged deep Space Missions. Although considerable discussions are now available in the literature on SW issues, routine Meteorological operational applications of SW forecast data and information for Space Environment are still yet to receive adequate attention. The paper attempts to fill this gap in the literature of SW. The paper examines the sensitivity and variability in 3-D continuum of Plasmas in response to solar radiation inputs into the magnetosphere under disturbed Sun condition. Specifically, the presence of plasma clouds in the form of Coronal Mass Ejections (CMEs) is stressed as a major source of danger to Space crews, spacecraft instrumentation and architecture charging problems as well as impacts on numerous radiation - sensitive human economic systems on Earth. Finally, the paper considers the application of model results in the form of effective monitoring of each of the two major phases of manned Spaceflights - take-off and re-entry phases where all-time assessment of spacecraft transient ambient micro-incabin and outside Space Environment is vital for all manned Spaceflights as recently evidenced by the loss of vital information during take-off of the February 1, 2003 US Columbia

  17. Infrared monitoring of the Space Station environment

    NASA Technical Reports Server (NTRS)

    Kostiuk, Theodor; Jennings, Donald E.; Mumma, Michael J.

    1988-01-01

    The measurement and monitoring of infrared emission in the environment of the Space Station has a twofold importance - for the study of the phenomena itself and as an aid in planning and interpreting Station based infrared experiments. Spectral measurements of the infrared component of the spacecraft glow will, along with measurements in other spectral regions, provide data necessary to fully understand and model the physical and chemical processes producing these emissions. The monitoring of the intensity of these emissions will provide background limits for Space Station based infrared experiments and permit the determination of optimum instrument placement and pointing direction. Continuous monitoring of temporal changes in the background radiation (glow) will also permit better interpretation of Station-based infrared earth sensing and astronomical observations. The primary processes producing infrared emissions in the Space Station environment are: (1) Gas phase excitations of Station generated molecules ( e.g., CO2, H2O, organics...) by collisions with the ambient flux of mainly O and N2. Molecular excitations and generation of new species by collisions of ambient molecules with Station surfaces. They provide a list of resulting species, transition energies, excitation cross sections and relevant time constants. The modeled spectrum of the excited species occurs primarily at wavelengths shorter than 8 micrometer. Emissions at longer wavelengths may become important during rocket firing or in the presence of dust.

  18. The Space Environment Sensor Suite for NPOESS

    NASA Astrophysics Data System (ADS)

    Rodriguez, J. V.; Eastman, K. W.; Eraker, J. H.; Belue, J.; Citrone, P.; Bloom, J. D.; Christensen, T. E.; Talmadge, S.; Ubhayakar, S. K.; Denig, W. F.

    2005-12-01

    The Space Environment Sensor Suite (SESS) is a set of instruments of the National Polar-orbiting Operational Environmental Satellite System (NPOESS) that takes measurements to produce space environment data products. The SESS includes a complement of instruments that provide in-situ data on particles, fields, aurora, and the ionosphere. The SESS team consists of the NPOESS Integrated Program Office (IPO), Northrop Grumman Space Technology (NGST) -- the prime contractor for NPOESS, Ball Aerospace & Technologies Corp. (BATC) -- lead systems integrator for SESS, key instrument/algorithm suppliers, and the science community advisors who represent the future users of SESS data products. This team has developed a baseline design and constellation that address the NPOESS requirements for the SESS-specific in-situ Environmental Data Records (EDRs). These EDRs are allocated to a Thermal Plasma Sensor (TPS), a Low Energy Particle Sensor (LEPS), a Medium Energy Particle Sensor (MEPS), and a High Energy Particle Sensor (HEPS) that are distributed on the multi-orbit NPOESS system architecture to satisfy the user community's performance and coverage needs. This paper will present details on the SESS sensors, the architecture and its expected performance.

  19. Space Environment Testing of Photovoltaic Array Systems at NASA's Marshall Space Flight Center

    NASA Technical Reports Server (NTRS)

    Schneider, Todd A.; Vaughn, Jason A.; Wright, Kenneth H., Jr.; Phillips, Brandon S.

    2015-01-01

    CubeSats, Communication Satellites, and Outer Planet Science Satellites all share one thing in common: Mission success depends on maintaining power in the harsh space environment. For a vast majority of satellites, spacecraft power is sourced by a photovoltaic (PV) array system. Built around PV cells, the array systems also include wiring, substrates, connectors, and protection diodes. Each of these components must function properly throughout the mission in order for power production to remain at nominal levels. Failure of even one component can lead to a crippling loss of power. To help ensure PV array systems do not suffer failures on-orbit due to the space environment, NASA's Marshall Space Flight Center (MSFC) has developed a wide ranging test and evaluation capability. Key elements of this capability include: Testing: a. Ultraviolet (UV) Exposure b. Charged Particle Radiation (Electron and Proton) c. Thermal Cycling d. Plasma and Beam Environments Evaluation: a. Electrostatic Discharge (ESD) Screening b. Optical Inspection and easurement c. PV Power Output including Large Area Pulsed Solar Simulator (LAPSS) measurements This paper will describe the elements of the space environment which particularly impact PV array systems. MSFC test capabilities will be described to show how the relevant space environments can be applied to PV array systems in the laboratory. A discussion of MSFC evaluation capabilities will also be provided. The sample evaluation capabilities offer test engineers a means to quantify the effects of the space environment on their PV array system or component. Finally, examples will be shown of the effects of the space environment on actual PV array materials tested at MSFC.

  20. Spacecraft System Failures and Anomalies Attributed to the Natural Space Environment

    NASA Technical Reports Server (NTRS)

    Bedingfield, Keith, L.; Leach, Richard D.; Alexander, Margaret B. (Editor)

    1996-01-01

    The natural space environment is characterized by many complex and subtle phenomena hostile to spacecraft. The effects of these phenomena impact spacecraft design, development, and operations. Space systems become increasingly susceptible to the space environment as use of composite materials and smaller, faster electronics increases. This trend makes an understanding of the natural space environment essential to accomplish overall mission objectives, especially in the current climate of better/cheaper/faster. This primer provides a brief overview of the natural space environment - definition, related programmatic issues, and effects on various spacecraft subsystems. The primary focus, however, is to catalog, through representative case histories, spacecraft failures and anomalies attributed to the natural space environment. This primer is one in a series of NASA Reference Publications currently being developed by the Electromagnetics and Aerospace Environments Branch, Systems Analysis and Integration Laboratory, Marshall Space Flight Center (MSFC), National Aeronautics and Space Administration (NASA).

  1. Microbial response to space environment, part B

    NASA Technical Reports Server (NTRS)

    Taylor, G. R.; Chassay, C. E.; Ellis, W. L.; Foster, B. G.; Volz, P. A.; Spizizen, J.; Buecker, H.; Wrenn, R. T.; Simmonds, R. C.; Long, R. A.

    1972-01-01

    The performance of the microbial response to space environment experiment is considered excellent by all investigators. For most microbial systems, only preliminary survival data are available at this time. None of the available data indicate space flight-mediated changes in cell viability or recovery. One quite important observation has been made at this early date, however. The eggs produced after mice had been infected with N. dubius larvae demonstrated a significant decrease in hatchability when compared to identical ground controls. Except for the fact that the Apollo 16 flight larvae had been on board the command module, treatment of the flown larvae and ground control larvae was the same; neither had been exposed to UV irradiation. The significance and implications of this finding are currently being studied.

  2. Relating space radiation environments to risk estimates

    NASA Technical Reports Server (NTRS)

    Curtis, Stanley B.

    1993-01-01

    A number of considerations must go into the process of determining the risk of deleterious effects of space radiation to travelers. Among them are (1) determination of the components of the radiation environment (particle species, fluxes and energy spectra) which will encounter, (2) determination of the effects of shielding provided by the spacecraft and the bodies of the travelers which modify the incident particle spectra and mix of particles, and (3) determination of relevant biological effects of the radiation in the organs of interest. The latter can then lead to an estimation of risk from a given space scenario. Clearly, the process spans many scientific disciplines from solar and cosmic ray physics to radiation transport theeory to the multistage problem of the induction by radiation of initial lesions in living material and their evolution via physical, chemical, and biological processes at the molecular, cellular, and tissue levels to produce the end point of importance.

  3. Relating space radiation environments to risk estimates

    SciTech Connect

    Curtis, S.B. ||

    1993-12-31

    A number of considerations must go into the process of determining the risk of deleterious effects of space radiation to travelers. Among them are (1) determination of the components of the radiation environment (particle species, fluxes and energy spectra) which will encounter, (2) determination of the effects of shielding provided by the spacecraft and the bodies of the travelers which modify the incident particle spectra and mix of particles, and (3) determination of relevant biological effects of the radiation in the organs of interest. The latter can then lead to an estimation of risk from a given space scenario. Clearly, the process spans many scientific disciplines from solar and cosmic ray physics to radiation transport theeory to the multistage problem of the induction by radiation of initial lesions in living material and their evolution via physical, chemical, and biological processes at the molecular, cellular, and tissue levels to produce the end point of importance.

  4. Space environment and lunar surface processes, 2

    NASA Technical Reports Server (NTRS)

    Comstock, G. M.

    1982-01-01

    The top few millimeters of a surface exposed to space represents a physically and chemically active zone with properties different from those of a surface in the environment of a planetary atmosphere. To meet the need or a quantitative synthesis of the various processes contributing to the evolution of surfaces of the Moon, Mercury, the asteroids, and similar bodies, (exposure to solar wind, solar flare particles, galactic cosmic rays, heating from solar radiation, and meteoroid bombardment), the MESS 2 computer program was developed. This program differs from earlier work in that the surface processes are broken down as a function of size scale and treated in three dimensions with good resolution on each scale. The results obtained apply to the development of soil near the surface and is based on lunar conditions. Parameters can be adjusted to describe asteroid regoliths and other space-related bodies.

  5. Space Environments and Effects: Trapped Proton Model

    NASA Technical Reports Server (NTRS)

    Huston, S. L.; Kauffman, W. (Technical Monitor)

    2002-01-01

    An improved model of the Earth's trapped proton environment has been developed. This model, designated Trapped Proton Model version 1 (TPM-1), determines the omnidirectional flux of protons with energy between 1 and 100 MeV throughout near-Earth space. The model also incorporates a true solar cycle dependence. The model consists of several data files and computer software to read them. There are three versions of the mo'del: a FORTRAN-Callable library, a stand-alone model, and a Web-based model.

  6. Technology Validation of Optical Fiber Cables for Space Flight Environments

    NASA Technical Reports Server (NTRS)

    Ott, Melanie N.; Friedberg, Patricia; Day, John H. (Technical Monitor)

    2000-01-01

    Periodically, commercially available (COTS) optical fiber cable assemblies are characterized for space flight usage under the NASA Electronic Parts and Packaging Program (NEPP). The purpose of this is to provide a family of optical fiber cable options to a variety of different harsh environments typical to space flight missions. The optical fiber cables under test are evaluated to bring out known failure mechanisms that are expected to occur during a typical mission. The tests used to characterize COTS cables include: (1) vacuum exposure, (2) thermal cycling, and (3) radiation exposure. Presented here are the results of the testing conducted at NASA Goddard Space Flight Center on COTS optical fiber cables over this past year. Several optical fiber cables were characterized for their thermal stability both during and after thermal cycling. The results show how much preconditioning is necessary for a variety of available cables to remain thermally stable in a space flight environment. Several optical fibers of dimensions 100/140/172 microns were characterized for their radiation effects at -125 C using the dose rate requirements of International Space Station. One optical fiber cable in particular was tested for outgassing to verify whether an acrylate coated fiber could be used in a space flight optical cable configuration.

  7. Electron environment specification models for Galileo

    NASA Astrophysics Data System (ADS)

    Lazaro, Didier; Bourdarie, Sebastien; Hands, Alex; Ryden, Keith; Nieminen, Petteri

    The MEO radiation hazard is becoming an increasingly important consideration with an ever rising number of satellites missions spending most of their time in this environment. This region lies in the heart of the highly dynamic electron radiation belt, where very large radiation doses can be encountered unless proper shielding to critical systems and components is applied. Significant internal charging hazards also arise in the MEO regime. For electron environment specification at Galileo altitude, new models have been developed and implemented: long term effects model for dose evaluation, statistical model for internal charging analysis and latitudinal model for ELDRS analysis. Models outputs, tools and validation with observations (Giove-A data) and existing models (such as FLUMIC) are presented . "Energetic Electron Environment Models for MEO" Co 21403/08/NL/JD in consortium with ONERA, QinetiQ, SSTL and CNES .

  8. Space Environment Testing of Photovoltaic Array Systems at NASA's Marshall Space Flight Center

    NASA Technical Reports Server (NTRS)

    Phillips, Brandon S.; Schneider, Todd A.; Vaughn, Jason A.; Wright, Kenneth H., Jr.

    2015-01-01

    To successfully operate a photovoltaic (PV) array system in space requires planning and testing to account for the effects of the space environment. It is critical to understand space environment interactions not only on the PV components, but also the array substrate materials, wiring harnesses, connectors, and protection circuitry (e.g. blocking diodes). Key elements of the space environment which must be accounted for in a PV system design include: Solar Photon Radiation, Charged Particle Radiation, Plasma, and Thermal Cycling. While solar photon radiation is central to generating power in PV systems, the complete spectrum includes short wavelength ultraviolet components, which photo-ionize materials, as well as long wavelength infrared which heat materials. High energy electron radiation has been demonstrated to significantly reduce the output power of III-V type PV cells; and proton radiation damages material surfaces - often impacting coverglasses and antireflective coatings. Plasma environments influence electrostatic charging of PV array materials, and must be understood to ensure that long duration arcs do not form and potentially destroy PV cells. Thermal cycling impacts all components on a PV array by inducing stresses due to thermal expansion and contraction. Given such demanding environments, and the complexity of structures and materials that form a PV array system, mission success can only be ensured through realistic testing in the laboratory. NASA's Marshall Space Flight Center has developed a broad space environment test capability to allow PV array designers and manufacturers to verify their system's integrity and avoid costly on-orbit failures. The Marshall Space Flight Center test capabilities are available to government, commercial, and university customers. Test solutions are tailored to meet the customer's needs, and can include performance assessments, such as flash testing in the case of PV cells.

  9. Electronic materials processing and the microgravity environment

    NASA Technical Reports Server (NTRS)

    Witt, A. F.

    1988-01-01

    The nature and origin of deficiencies in bulk electronic materials for device fabrication are analyzed. It is found that gravity generated perturbations during their formation account largely for the introduction of critical chemical and crystalline defects and, moreover, are responsible for the still existing gap between theory and experiment and thus for excessive reliance on proprietary empiricism in processing technology. Exploration of the potential of reduced gravity environment for electronic materials processing is found to be not only desirable but mandatory.

  10. Coatings in space environment. [for satellite thermal control

    NASA Technical Reports Server (NTRS)

    Triolo, J. J.; Heaney, J. B.; Hass, G.

    1978-01-01

    The behavior in space environment of evaporated Al uncoated and coated with reactively deposited silicon oxide (SiOx), electron beam evaporated SiO2 and Al2O3, and Al and Ag coated with double layers of Al2O3 + SiOx is compared with metallized Teflon and Kapton, anodized Al (Alzak), and white paints. Flight data from three calorimetric experiments and one reflectometer flown in different orbital environments are compared with laboratory test data. The results demonstrate that evaporated thin films are extremely versatile and stable coatings for space applications. Through the use of control samples studied in different laboratory tests and monitored for up to 12,000 hours of solar exposure in different orbits, a classification of orbital severity and an estimate of laboratory simulation accuracy is obtained.

  11. Control of Space-Based Electron Beam Free Form Fabrication

    NASA Technical Reports Server (NTRS)

    Seifzer. W. J.; Taminger, K. M.

    2007-01-01

    Engineering a closed-loop control system for an electron beam welder for space-based additive manufacturing is challenging. For earth and space based applications, components must work in a vacuum and optical components become occluded with metal vapor deposition. For extraterrestrial applications added components increase launch weight, increase complexity, and increase space flight certification efforts. Here we present a software tool that closely couples path planning and E-beam parameter controls into the build process to increase flexibility. In an environment where data collection hinders real-time control, another approach is considered that will still yield a high quality build.

  12. Electronic Components and Circuits for Extreme Temperature Environments

    NASA Technical Reports Server (NTRS)

    Patterson, Richard L.; Hammoud, Ahmad; Dickman, John E.; Gerber, Scott

    2003-01-01

    Planetary exploration missions and deep space probes require electrical power management and control systems that are capable of efficient and reliable operation in very low temperature environments. Presently, spacecraft operating in the cold environment of deep space carry a large number of radioisotope heating units in order to maintain the surrounding temperature of the on-board electronics at approximately 20 C. Electronics capable of operation at cryogenic temperatures will not only tolerate the hostile environment of deep space but also reduce system size and weight by eliminating or reducing the radioisotope heating units and their associate structures; thereby reducing system development as well as launch costs. In addition, power electronic circuits designed for operation at low temperatures are expected to result in more efficient systems than those at room temperature. This improvement results from better behavior and tolerance in the electrical and thermal properties of semiconductor and dielectric materials at low temperatures. The Low Temperature Electronics Program at the NASA Glenn Research Center focuses on research and development of electrical components, circuits, and systems suitable for applications in the aerospace environment and deep space exploration missions. Research is being conducted on devices and systems for reliable use down to cryogenic temperatures. Some of the commercial-off-the-shelf as well as developed components that are being characterized include switching devices, resistors, magnetics, and capacitors. Semiconductor devices and integrated circuits including digital-to-analog and analog-to-digital converters, DC/DC converters, operational amplifiers, and oscillators are also being investigated for potential use in low temperature applications. An overview of the NASA Glenn Research Center Low Temperature Electronic Program will be presented in this paper. A description of the low temperature test facilities along with

  13. Space environment simulation at radiation test of nonmetallic materials

    NASA Astrophysics Data System (ADS)

    Briskman, B. A.; Klinshpont, E. R.; Tupikov, V. I.

    1999-05-01

    Russia [1] (B.A. Briskman, V.I. Toupikov, E.N. Lesnovsky, Proceedings of the Seventh International Symposium on Materials in Space Environment, Toulouse, France, 16-20 June 1997, ESA, SP-399, p. 537) has proposed new international standard for the testing of materials to simulated space radiation. The proposal was submitted to ISO (The International Organization for Standards) Technical Committee 20 (Aircraft and Space Vehicles), Subcommittee 14 (Space Systems and Operations) and was approved as Working Draft 15856 at the Los-Angeles meeting (1997). The second version of the draft was approved at the Beijing meeting (1998). The standard extends to space ionizing radiation: protons, electrons, solar ultraviolet, soft X-radiation, bremsstrahlung, that effect the polymeric materials of space engineering. The special feature of interaction of the space ionizing radiation with materials is the localization of the main part of absorbed energy in thin near-surface layers. Numerous problems appear in simulating the ionizing radiation impact, which require a solution for correct conduction of the on-ground tests.

  14. Natural environment design requirements for the space tug

    NASA Technical Reports Server (NTRS)

    West, G. S., Jr.

    1973-01-01

    The natural environment design requirements for the space tug are presented. Since the Space Tug is carried as cargo to orbital altitudes in the space shuttle bay, orbital environmental impacts and short-period atmospheric density variations are the main concerns. The subjects discussed are: (1) natural environment, (2) neutral environment, (3) charged particles, (4) radiation, and (5) meteoroid hazards.

  15. Electronic ceramics in high temperature environments

    SciTech Connect

    Searcy, A.W.; Meschi, D.J.

    1980-11-01

    Simple thermodynamic means are described for understanding and predicting the influence of temperature changes in various environments on electronic properties of ceramics. Thermal gradients, thermal cycling and vacuum annealing are discussed, as well as the variations of activities and solubilities with temperature.

  16. Predicting Material Performance in the Space Environment from Laboratory Test Data, Static Design Environments, and Space Weather Models

    NASA Technical Reports Server (NTRS)

    Minow, Josep I.; Edwards, David L.

    2008-01-01

    Qualifying materials for use in the space environment is typically accomplished with laboratory exposures to simulated UV/EUV, atomic oxygen, and charged particle radiation environments with in-situ or subsequent measurements of material properties of interest to the particular application. Choice of environment exposure levels are derived from static design environments intended to represent either mean or extreme conditions that are anticipated to be encountered during a mission. The real space environment however is quite variable. Predictions of the on orbit performance of a material qualified to laboratory environments can be done using information on 'space weather' variations in the real environment. This presentation will first review the variability of space environments of concern for material degradation and then demonstrate techniques for using test data to predict material performance in a variety of space environments from low Earth orbit to interplanetary space using historical measurements and space weather models.

  17. Test and Analysis Capabilities of the Space Environment Effects Team at Marshall Space Flight Center

    NASA Technical Reports Server (NTRS)

    Finckenor, M. M.; Edwards, D. L.; Vaughn, J. A.; Schneider, T. A.; Hovater, M. A.; Hoppe, D. T.

    2002-01-01

    Marshall Space Flight Center has developed world-class space environmental effects testing facilities to simulate the space environment. The combined environmental effects test system exposes temperature-controlled samples to simultaneous protons, high- and low-energy electrons, vacuum ultraviolet (VUV) radiation, and near-ultraviolet (NUV) radiation. Separate chambers for studying the effects of NUV and VUV at elevated temperatures are also available. The Atomic Oxygen Beam Facility exposes samples to atomic oxygen of 5 eV energy to simulate low-Earth orbit (LEO). The LEO space plasma simulators are used to study current collection to biased spacecraft surfaces, arcing from insulators and electrical conductivity of materials. Plasma propulsion techniques are analyzed using the Marshall magnetic mirror system. The micro light gas gun simulates micrometeoroid and space debris impacts. Candidate materials and hardware for spacecraft can be evaluated for durability in the space environment with a variety of analytical techniques. Mass, solar absorptance, infrared emittance, transmission, reflectance, bidirectional reflectance distribution function, and surface morphology characterization can be performed. The data from the space environmental effects testing facilities, combined with analytical results from flight experiments, enable the Environmental Effects Group to determine optimum materials for use on spacecraft.

  18. Development of Electronics for Low Temperature Space Missions

    NASA Technical Reports Server (NTRS)

    Patterson, Richard L.; Hammoud, Ahmad; Dickman, John E.; Gerber, Scott; Overton, Eric

    2000-01-01

    The operation of electronic systems at cryogenic temperatures is anticipated for many future NASA space missions such as deep space probes and planetary surface exploration. For example, an unheated interplanetary probe launched to explore the rings of Saturn would reach an average temperature near Saturn of about -183 C. In addition to surviving the deep space harsh environment, electronics capable of low temperature operation would contribute to improving circuit performance, increasing system efficiency, and reducing payload development and launch costs. Terrestrial applications where components and systems must operate in low temperature environments include cryogenic instrumentation, superconducting magnetic energy storage, magnetic levitation transportation system, and arctic exploration. An on-going research and development program on low temperature electronics at the NASA Glenn Research Center focuses on the development of efficient power systems capable of surviving and exploiting the advantages of low temperature environments. Inhouse efforts include the design, fabrication, and characterization of low temperature power systems and the development of supporting technologies for low temperature operations, such as dielectric and insulating materials, semiconductor devices, passive power components, opto-electronic devices, as well as packaging and integration of the developed components into prototype flight hardware.

  19. Electronic components and systems for cryogenic space applications

    NASA Astrophysics Data System (ADS)

    Patterson, R. L.; Hammoud, A.; Dickman, J. E.; Gerber, S.; Elbuluk, M. E.; Overton, E.

    2002-05-01

    Electronic components and systems capable of operation at cryogenic temperatures are anticipated in many future NASA space missions such as deep space probes and planetary surface exploration. For example, an unheated interplanetary probe launched to explore the rings of Saturn would reach an average temperature near Saturn of about -183 °C. In addition to surviving the deep space harsh environment, electronics capable of low temperature operation would contribute to improving circuit performance, increasing system efficiency, and reducing payload development and launch costs. Terrestrial applications where components and systems must operate in low temperature environments include cryogenic instrumentation, superconducting magnetic energy storage, magnetic levitation transportation systems, and arctic exploration. An on-going R&D program at the NASA Glenn Research Center focuses on the development of reliable electronic devices and efficient power systems capable of surviving and operating in low temperature environments. An overview of the program will be presented in this paper. A description of the low temperature test facilities along with selected data obtained from in-house electronic component and small system testing will also be discussed. .

  20. Space environment: A new dimension in the preparation of unique solids

    NASA Technical Reports Server (NTRS)

    Gatos, H. C.

    1972-01-01

    The preparation of solids, particularly electronic solids in space is discussed. Particular attention is given to the effect of non-gravational environments on the development of homogeneous materials that cannot be manufactured on earth.

  1. Space Environments and Effects Program (SEE)

    NASA Technical Reports Server (NTRS)

    Yhisreal-Rivas, David M.

    2013-01-01

    The need to preserve works and NASA documented articles is done via the collection of various Space Environments and Effects (SEE) related articles. (SEE) contains and lists the various projects that are ongoing, or have been conducted with the help of NASA. The goal of the (SEE) program is to make publicly available the environment technologies that are required to design, manufacture and operate reliable, cost-effective spacecraft for the government and commercial sectors. Of the many projects contained within the (SEE) program the Lunar-E Library and Spacecraft Materials Selector (SMS) have been selected for a more user friendly means to make the tools easily available to the public. This information which is still available required a person or entity to request access from a point of contact at NASA and wait for the requested bundled software DVD via postal service. Redesigning the material presentation and availability has been mapped to a single step process with faster turnaround time via Materials and Processes Technical Information System (MAPTIS) database. This process requires users to register and be verified in order to gain access to the information contained within. Aiding in the progression of making the software tools/documents available required a combination of specialized in-house data gathering software tools and software archeology.

  2. JPL Space Telecommunications Radio System Operating Environment

    NASA Technical Reports Server (NTRS)

    Lux, James P.; Lang, Minh; Peters, Kenneth J.; Taylor, Gregory H.; Duncan, Courtney B.; Orozco, David S.; Stern, Ryan A.; Ahten, Earl R.; Girard, Mike

    2013-01-01

    A flight-qualified implementation of a Software Defined Radio (SDR) Operating Environment for the JPL-SDR built for the CoNNeCT Project has been developed. It is compliant with the NASA Space Telecommunications Radio System (STRS) Architecture Standard, and provides the software infrastructure for STRS compliant waveform applications. This software provides a standards-compliant abstracted view of the JPL-SDR hardware platform. It uses industry standard POSIX interfaces for most functions, as well as exposing the STRS API (Application Programming In terface) required by the standard. This software includes a standardized interface for IP components instantiated within a Xilinx FPGA (Field Programmable Gate Array). The software provides a standardized abstracted interface to platform resources such as data converters, file system, etc., which can be used by STRS standards conformant waveform applications. It provides a generic SDR operating environment with a much smaller resource footprint than similar products such as SCA (Software Communications Architecture) compliant implementations, or the DoD Joint Tactical Radio Systems (JTRS).

  3. Effects of space environment on structural materials

    NASA Technical Reports Server (NTRS)

    Miglionico, C.; Stein, C.; Roybal, R.; Robertson, R.; Murr, L. E.; Quinones, S.; Rivas, J.; Marquez, B.; Advani, A. H.; Fisher, W. W.

    1992-01-01

    A preliminary study of materials exposed in space in a low Earth orbit for nearly six years has revealed a wide range of micrometeorite or microparticle impact craters ranging in size from 1 to 1000 micron in diameter, debris particles from adjacent and distant materials systems, reaction products, and other growth features on the specimen surfaces, and related phenomena. The exposed surface features included fine grained and nearly amorphous materials as well as a large array of single crystal particles. A replication type, lift off technique was developed to remove reaction products and debris from the specimen surfaces in order to isolate them from the background substrate without creating microchemical or microstructural artifacts or alterations. This resulted in surface features resting on a carbon support film which was virtually invisible to observation by electron microscopy and nondispersive x ray analysis. Some evidence for blisters on leading edge aluminum alloy surfaces and a high surface region concentration of oxygen determined by Auger electron spectrometry suggests oxygen effects where fluences exceed 10(exp 21) atoms/sq cm.

  4. A Coordinated Effort to Address Space Weather and Environment Needs

    NASA Technical Reports Server (NTRS)

    Minow, Joe; Spann, James F.; Edward, David L.; Burns, Howard D.; Gallagher, Dennis; Xapos, Mike; DeGroh, Kim

    2010-01-01

    The growing need for coordination of the many aspects of space environments is directly related to our increasing dependence on space assets. An obvious result is that there is a need for a coordinated effort to organize and make accessible the increasing number of space environment products that include space environment models and observations, material testing, and forecasting tools. This paper outlines a concept to establish a NASA-level Applied Spaceflight Environments (ASE) office that will provide coordination and funding for sustained multi-program support in three technical areas; (1) natural environments characterization and modeling, (2) environmental effects on materials and systems, (3) and operational and forecasting space environments modeling. Additionally the ASE office will serve as an entry point of contact for external users who wish to take advantage of data and assets associated with space environments, including space weather.

  5. Logistics, electronic commerce, and the environment

    NASA Astrophysics Data System (ADS)

    Sarkis, Joseph; Meade, Laura; Talluri, Srinivas

    2002-02-01

    Organizations realize that a strong supporting logistics or electronic logistics (e-logistics) function is important from both commercial and consumer perspectives. The implications of e-logistics models and practices cover the forward and reverse logistics functions of organizations. They also have direct and profound impact on the natural environment. This paper will focus on a discussion of forward and reverse e-logistics and their relationship to the natural environment. After discussion of the many pertinent issues in these areas, directions of practice and implications for study and research are then described.

  6. Electronic Components and Systems for Cryogenic Space Applications

    NASA Technical Reports Server (NTRS)

    Patterson, R. L.; Hammoud, A.; Dickman, J. E.; Gerber, S.; Elbuluk, M. E.; Overton, E.

    2001-01-01

    Electronic components and systems capable of operation at cryogenic temperatures are anticipated in many future NASA space missions such as deep space probes and planetary surface exploration. For example, an unheated interplanetary probe launched to explore the rings of Saturn would reach an average temperature near Saturn of about - 183 C. In addition to surviving the deep space harsh environment, electronics capable of low temperature operation would contribute to improving circuit performance, increasing system efficiency, and reducing payload development and launch costs. Terrestrial applications where components and systems must operate in low temperature environments include cryogenic instrumentation, superconducting magnetic energy storage, magnetic levitation transportation system, and arctic exploration. An on-going research and development program at the NASA Glenn Research Center focuses on the development of reliable electronic devices and efficient power systems capable of surviving in low temperature environments. An overview of the program will be presented in this paper. A description of the low temperature test facilities along with selected data obtained from in-house component testing will also be discussed. Ongoing research activities that are being performed in collaboration with various organizations will also be presented.

  7. Development of Electronics for Low-Temperature Space Missions

    NASA Technical Reports Server (NTRS)

    Patterson, Richard L.; Hammoud, Ahmad; Dickman, John E.; Gerber, Scott S.; Overton, Eric

    2001-01-01

    Electronic systems that are capable of operating at cryogenic temperatures will be needed for many future NASA space missions, including deep space probes and spacecraft for planetary surface exploration. In addition to being able to survive the harsh deep space environment, low-temperature electronics would help improve circuit performance, increase system efficiency, and reduce payload development and launch costs. Terrestrial applications where components and systems must operate in low-temperature environments include cryogenic instrumentation, superconducting magnetic energy storage, magnetic levitation transportation systems, and arctic exploration. An ongoing research and development project for the design, fabrication, and characterization of low-temperature electronics and supporting technologies at NASA Glenn Research Center focuses on efficient power systems capable of surviving in and exploiting the advantages of low-temperature environments. Supporting technologies include dielectric and insulating materials, semiconductor devices, passive power components, optoelectronic devices, and packaging and integration of the developed components into prototype flight hardware. An overview of the project is presented, including a description of the test facilities, a discussion of selected data from component testing, and a presentation of ongoing research activities being performed in collaboration with various organizations.

  8. BUSEFL: The Boston University Space Environment Forecast Laboratory

    SciTech Connect

    Contos, A.R.; Sanchez, L.A.; Jorgensen, A.M.

    1996-07-01

    BUSEFL (Boston University Space Environment Forecast Laboratory) is a comprehensive, integrated project to address the issues and implications of space weather forecasting. An important goal of the BUSEFL mission is to serve as a testing ground for space weather algorithms and operational procedures. One such algorithm is the Magnetospheric Specification and Forecast Model (MSFM), which may be implemented in possible future space weather prediction centers. Boston University Student-satellite for Applications and Training (BUSAT), the satellite component of BUSEFL, will incorporate four experiments designed to measure (1) the earth{close_quote}s magnetic field, (2) distribution of energetic electrons trapped in the earth{close_quote}s radiation belts, (3) the mass and charge composition of the ion fluxes along the magnetic field lines and (4) the auroral forms at the foot of the field line in the auroral zones. Data from these experiments will be integrated into a ground system to evaluate space weather prediction codes. Data from the BUSEFL mission will be available to the scientific community and the public through media such as the World Wide Web (WWW). {copyright} {ital 1996 American Institute of Physics.}

  9. Radiation Belt Environment Model: Application to Space Weather and Beyond

    NASA Technical Reports Server (NTRS)

    Fok, Mei-Ching H.

    2011-01-01

    Understanding the dynamics and variability of the radiation belts are of great scientific and space weather significance. A physics-based Radiation Belt Environment (RBE) model has been developed to simulate and predict the radiation particle intensities. The RBE model considers the influences from the solar wind, ring current and plasmasphere. It takes into account the particle drift in realistic, time-varying magnetic and electric field, and includes diffusive effects of wave-particle interactions with various wave modes in the magnetosphere. The RBE model has been used to perform event studies and real-time prediction of energetic electron fluxes. In this talk, we will describe the RBE model equation, inputs and capabilities. Recent advancement in space weather application and artificial radiation belt study will be discussed as well.

  10. Development of a Temperature Sensor for Jet Engine and Space Missions Environments

    NASA Technical Reports Server (NTRS)

    Patterson, Richard L.; Hammoud, Ahmad; Culley, Dennis E.; Elbuluk, Malik

    2008-01-01

    Electronic systems in aerospace and in space exploration missions are expected to encounter extreme temperatures and wide thermal swings. To address the needs for extreme temperature electronics, research efforts exist at the NASA Glenn Research Center (GRC) to develop and evaluate electronics for extreme temperature operations, and to establish their reliability under extreme temperature operation and thermal cycling; conditions that are typical of both the aerospace and space environments. These efforts are supported by the NASA Fundamental Aeronautics/Subsonic Fixed Wing Program and by the NASA Electronic Parts and Packaging (NEPP) Program. This work reports on the results obtained on the development of a temperature sensor geared for use in harsh environments.

  11. Creating flowing space plasma environments with VASIMR

    NASA Astrophysics Data System (ADS)

    Bering, Edgar, III; Longmier, Benjamin; Glover, Tim; Chang-Diaz, Franklin; Squire, Jared; Brukardt, Michael

    2008-11-01

    Recent results from the operation of a 125 cubic meter space simulation chamber are presented. The primary role of the vacuum chamber is to support the operation of the Variable Specific Impulse Magnetoplasma Rocket (VASIMR), a high power magnetoplasma rocket, capable of Isp/thrust modulation at constant power. However, magnetospheric and heliospheric plasma environments can be produced with the VASIMR plasma source with a power range of 0.5 to 200 kW, producing a H, D, Ne, or Ar flowing plasma with flow velocities in excess of 20,000 km/s. The plasma is produced by a helicon discharge. The bulk of the energy is added by ion cyclotron resonance heating (ICRH.) Axial momentum is obtained by adiabatic expansion of the plasma in a magnetic nozzle. Particle flux and particle energy can be adjusted independently of each other, which is primarily achieved by the partitioning of the RF power to the helicon and ICRH systems, with the proper adjustment of the propellant flow. Ion dynamics in the flowing plasma is studied using probes, gridded energy analyzers (RPA's), microwave interferometry and optical techniques.

  12. Degradation of thermal shield materials in the space radiation environment

    NASA Astrophysics Data System (ADS)

    Shimoji, S.; Kimura, H.; Koitabashi, M.; Imamura, T.; Kasai, R.; Matsushita, M.

    1983-12-01

    Changes in temperature distribution data of Experimental Technology Satellite 4 after its 3 months mission term are discussed. Analysis of the data suggested that the thermal shields loose their function in the space radiation environment. The effect of energetic particles on the shield materials was investigated. Electron beams of 500 keV and proton beams of 900 keV were irradiated on silver-Teflon and aluminized Kapton films. The fluences were changed between 10 to the 14th and 10 to the 16th power sqcm. Temperature varied between -100 and 100C. Solar absorptance, infrared emittance, tensile strength and elongation rate were measured. Thermogravimetry, infrared spectroscopy and X-ray diffraction were performed. Electron fluxes have remarkable effects on the mechanical properties, proton fluxes on the thermophysical properties of silver-Teflon film. Kapton films do not change much.

  13. Power Electronics Being Developed for Deep Space Cryogenic Applications

    NASA Technical Reports Server (NTRS)

    Patterson, Richard L.; Hammoud, Ahmad

    2003-01-01

    Electronic circuits and systems designed for deep space missions need to operate reliably and efficiently in harsh environments that include very low temperatures. Spacecraft that operate in such cold environments carry a large number of heaters so that the ambient temperature for the onboard electronics remains near 20 C. Electronics that can operate at cryogenic temperatures will simplify system design and reduce system size and weight by eliminating the heaters and their associated structures. As a result, system development and launch cost will be reduced. At the NASA Glenn Research Center, an ongoing program is focusing on the development of power electronics geared for deep space low-temperature environments. The research and development efforts include electrical components design, circuit design and construction, and system integration and demonstration at cryogenic temperatures. Investigations are being carried out on circuits and systems that are targeted for use in NASA missions where low temperatures will be encountered: devices such as ceramic and tantalum capacitors, metal film resistors, semiconductor switches, magnetics, and integrated circuits including dc/dc converters, operational amplifiers, voltage references, and motor controllers. Test activities cover a wide range of device and circuit performance under simple as well as complex test conditions, such as multistress and thermal cycling. The effect of low-temperature conditions on the switching characteristics of an advanced silicon-on-insulator field effect transistor is shown. For gate voltages (VGS) below 2.6 V, drain currents at -190 C are lower than drain currents at room temperature (20 C).

  14. 12 CFR 7.5010 - Shared electronic space.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 1 2010-01-01 2010-01-01 false Shared electronic space. 7.5010 Section 7.5010 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY BANK ACTIVITIES AND OPERATIONS Electronic Activities § 7.5010 Shared electronic space. National banks that share electronic space,...

  15. 12 CFR 7.5010 - Shared electronic space.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 1 2014-01-01 2014-01-01 false Shared electronic space. 7.5010 Section 7.5010 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY BANK ACTIVITIES AND OPERATIONS Electronic Activities § 7.5010 Shared electronic space. National banks that share electronic space,...

  16. 12 CFR 7.5010 - Shared electronic space.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 1 2012-01-01 2012-01-01 false Shared electronic space. 7.5010 Section 7.5010 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY BANK ACTIVITIES AND OPERATIONS Electronic Activities § 7.5010 Shared electronic space. National banks that share electronic space,...

  17. 12 CFR 7.5010 - Shared electronic space.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 1 2013-01-01 2013-01-01 false Shared electronic space. 7.5010 Section 7.5010 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY BANK ACTIVITIES AND OPERATIONS Electronic Activities § 7.5010 Shared electronic space. National banks that share electronic space,...

  18. 12 CFR 7.5010 - Shared electronic space.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 1 2011-01-01 2011-01-01 false Shared electronic space. 7.5010 Section 7.5010 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY BANK ACTIVITIES AND OPERATIONS Electronic Activities § 7.5010 Shared electronic space. National banks that share electronic space,...

  19. Extreme Environment Technologies for Space and Terrestrial Applications

    NASA Technical Reports Server (NTRS)

    Balint, Tibor S.; Cutts, James A.; Kolawa, Elizabeth A.; Peterson, Craig E.

    2008-01-01

    Over the next decades, NASA's planned solar system exploration missions are targeting planets, moons and small bodies, where spacecraft would be expected to encounter diverse extreme environmental (EE) conditions throughout their mission phases. These EE conditions are often coupled. For instance, near the surface of Venus and in the deep atmospheres of giant planets, probes would experience high temperatures and pressures. In the Jovian system low temperatures are coupled with high radiation. Other environments include thermal cycling, and corrosion. Mission operations could also introduce extreme conditions, due to atmospheric entry heat flux and deceleration. Some of these EE conditions are not unique to space missions; they can be encountered by terrestrial assets from the fields of defense,oil and gas, aerospace, and automotive industries. In this paper we outline the findings of NASA's Extreme Environments Study Team, including discussions on state of the art and emerging capabilities related to environmental protection, tolerance and operations in EEs. We will also highlight cross cutting EE mitigation technologies, for example, between high g-load tolerant impactors for Europa and instrumented projectiles on Earth; high temperature electronics sensors on Jupiter deep probes and sensors inside jet engines; and pressure vessel technologies for Venus probes and sea bottom monitors. We will argue that synergistic development programs between these fields could be highly beneficial and cost effective for the various agencies and industries. Some of these environments, however, are specific to space and thus the related technology developments should be spear headed by NASA with collaboration from industry and academia.

  20. Extreme environment technologies for space and terrestrial applications

    NASA Astrophysics Data System (ADS)

    Balint, Tibor S.; Cutts, James A.; Kolawa, Elizabeth A.; Peterson, Craig E.

    2008-04-01

    Over the next decades, NASA's planned solar system exploration missions are targeting planets, moons and small bodies, where spacecraft would be expected to encounter diverse extreme environmental (EE) conditions throughout their mission phases. These EE conditions are often coupled. For instance, near the surface of Venus and in the deep atmospheres of giant planets, probes would experience high temperatures and pressures. In the Jovian system low temperatures are coupled with high radiation. Other environments include thermal cycling, and corrosion. Mission operations could also introduce extreme conditions, due to atmospheric entry heat flux and deceleration. Some of these EE conditions are not unique to space missions; they can be encountered by terrestrial assets from the fields of defense, oil and gas, aerospace, and automotive industries. In this paper we outline the findings of NASA's Extreme Environments Study Team, including discussions on state of the art and emerging capabilities related to environmental protection, tolerance and operations in EEs. We will also highlight cross cutting EE mitigation technologies, for example, between high g-load tolerant impactors for Europa and instrumented projectiles on Earth; high temperature electronics sensors on Jupiter deep probes and sensors inside jet engines; and pressure vessel technologies for Venus probes and sea bottom monitors. We will argue that synergistic development programs between these fields could be highly beneficial and cost effective for the various agencies and industries. Some of these environments, however, are specific to space and thus the related technology developments should be spearheaded by NASA with collaboration from industry and academia.

  1. Targeted and comprehensive space-environment sensors: description and recommendations

    SciTech Connect

    Reeves, Geoffrey; O'Brien, Paul; Mazur, Joe; Ginet, Gregory

    2009-01-01

    We discuss the roles of the two classes of space-environment sensors on operational space systems: (1) Targeted sensors capable of measuring the environment and effects at a level sufficient for providing situational awareness for the host spacecraft and (2) Comprehensive sensors capable of providing detailed environment measurements that can be mapped to a broad region of near-Earth space, providing global situational awareness and quantitative characterization of the environment. Our purpose is to show the usefulness of a heterogeneous architecture with both classes of sensors for the near-term and long-term needs of National Security Space

  2. The ionizing radiation environment in space and its effects

    SciTech Connect

    Adams, Jim; Falconer, David; Fry, Dan

    2012-11-20

    The ionizing radiation environment in space poses a hazard for spacecraft and space crews. The hazardous components of this environment are reviewed and those which contribute to radiation hazards and effects identified. Avoiding the adverse effects of space radiation requires design, planning, monitoring and management. Radiation effects on spacecraft are avoided largely though spacecraft design. Managing radiation exposures of space crews involves not only protective spacecraft design and careful mission planning. Exposures must be managed in real time. The now-casting and forecasting needed to effectively manage crew exposures is presented. The techniques used and the space environment modeling needed to implement these techniques are discussed.

  3. Electron distribution functions in electric field environments

    NASA Technical Reports Server (NTRS)

    Rudolph, Terence H.

    1991-01-01

    The amount of current carried by an electric discharge in its early stages of growth is strongly dependent on its geometrical shape. Discharges with a large number of branches, each funnelling current to a common stem, tend to carry more current than those with fewer branches. The fractal character of typical discharges was simulated using stochastic models based on solutions of the Laplace equation. Extension of these models requires the use of electron distribution functions to describe the behavior of electrons in the undisturbed medium ahead of the discharge. These electrons, interacting with the electric field, determine the propagation of branches in the discharge and the way in which further branching occurs. The first phase in the extension of the referenced models , the calculation of simple electron distribution functions in an air/electric field medium, is discussed. Two techniques are investigated: (1) the solution of the Boltzmann equation in homogeneous, steady state environments, and (2) the use of Monte Carlo simulations. Distribution functions calculated from both techniques are illustrated. Advantages and disadvantages of each technique are discussed.

  4. Lithium electronic environments in rechargeable battery electrodes

    NASA Astrophysics Data System (ADS)

    Hightower, Adrian

    This work investigates the electronic environments of lithium in the electrodes of rechargeable batteries. The use of electron energy-loss spectroscopy (EELS) in conjunction with transmission electron microscopy (TEM) is a novel approach, which when coupled with conventional electrochemical experiments, yield a thorough picture of the electrode interior. Relatively few EELS experiments have been preformed on lithium compounds owing to their reactivity. Experimental techniques were established to minimize sample contamination and control electron beam damage to studied compounds. Lithium hydroxide was found to be the most common product of beam damaged lithium alloys. Under an intense electron beam, halogen atoms desorbed by radiolysis in lithium halides. EELS spectra from a number of standard lithium compounds were obtained in order to identify the variety of spectra encountered in lithium rechargeable battery electrodes. Lithium alloys all displayed characteristically broad Li K-edge spectra, consistent with transitions to continuum states. Transitions to bound states were observed in the Li K and oxygen K-edge spectra of lithium oxides. Lithium halides were distinguished by their systematic chemical shift proportional to the anion electronegativity. Good agreement was found with measured lithium halide spectra and electron structure calculations using a self-consistant multiscattering code. The specific electrode environments of LiC6, LiCoO2, and Li-SnO were investigated. Contrary to published XPS predictions, lithium in intercalated graphite was determined to be in more metallic than ionic. We present the first experimental evidence of charge compensation by oxygen ions in deintercalated LiCoO2. Mossbauer studies on cycled Li-SnO reveal severely defective structures on an atomic scale. Metal hydride systems are presented in the appendices of this thesis. The mechanical alloying of immiscible Fe and Mg powders resulted in single-phase bcc alloys of less than 20

  5. Electronic nose for space program applications

    NASA Technical Reports Server (NTRS)

    Young, Rebecca C.; Buttner, William J.; Linnell, Bruce R.; Ramesham, Rajeshuni

    2003-01-01

    The ability to monitor air contaminants in the shuttle and the International Space Station is important to ensure the health and safety of astronauts, and equipment integrity. Three specific space applications have been identified that would benefit from a chemical monitor: (a) organic contaminants in space cabin air; (b) hypergolic propellant contaminants in the shuttle airlock; (c) pre-combustion signature vapors from electrical fires. NASA at Kennedy Space Center (KSC) is assessing several commercial and developing electronic noses (E-noses) for these applications. A short series of tests identified those E-noses that exhibited sufficient sensitivity to the vapors of interest. Only two E-noses exhibited sufficient sensitivity for hypergolic fuels at the required levels, while several commercial E-noses showed sufficient sensitivity of common organic vapors. These E-noses were subjected to further tests to assess their ability to identify vapors. Development and testing of E-nose models using vendor supplied software packages correctly identified vapors with an accuracy of 70-90%. In-house software improvements increased the identification rates between 90 and 100%. Further software enhancements are under development. Details on the experimental setup, test protocols, and results on E-nose performance are presented in this paper along with special emphasis on specific software enhancements. c2003 Elsevier Science B.V. All rights reserved.

  6. Electronic nose for space program applications.

    PubMed

    Young, Rebecca C; Buttner, William J; Linnell, Bruce R; Ramesham, Rajeshuni

    2003-08-01

    The ability to monitor air contaminants in the shuttle and the International Space Station is important to ensure the health and safety of astronauts, and equipment integrity. Three specific space applications have been identified that would benefit from a chemical monitor: (a) organic contaminants in space cabin air; (b) hypergolic propellant contaminants in the shuttle airlock; (c) pre-combustion signature vapors from electrical fires. NASA at Kennedy Space Center (KSC) is assessing several commercial and developing electronic noses (E-noses) for these applications. A short series of tests identified those E-noses that exhibited sufficient sensitivity to the vapors of interest. Only two E-noses exhibited sufficient sensitivity for hypergolic fuels at the required levels, while several commercial E-noses showed sufficient sensitivity of common organic vapors. These E-noses were subjected to further tests to assess their ability to identify vapors. Development and testing of E-nose models using vendor supplied software packages correctly identified vapors with an accuracy of 70-90%. In-house software improvements increased the identification rates between 90 and 100%. Further software enhancements are under development. Details on the experimental setup, test protocols, and results on E-nose performance are presented in this paper along with special emphasis on specific software enhancements. PMID:14584511

  7. Space-time separation of electronic correlations

    NASA Astrophysics Data System (ADS)

    Tomczak, Jan M.; Schäfer, Thomas; Klebel, Benjamin; Toschi, Alessandro

    While second-order phase transitions always cause strong nonlocal fluctuations, their effect on spectral properties crucially depends on the dimensionality. First, we show that for the important case of three dimensions the electron self-energy is well separable into a local dynamical part and static nonlocal contributions. In particular, using the dynamical vertex approximation for the doped 3D Hubbard model, we demonstrate that the quasiparticle weight remains essentially momentum independent, despite overall large nonlocal corrections to the self-energy when approaching the spin-ordered state. This generalizes earlier empirical findings of this property in the iron pnictides and transition metal oxides based on Hedin's GW approximation. With this insight, we here propose a ''space-time-separated'' scheme for many-body perturbation theory that is up to ten times more efficient than current implementations. Finally, we discuss limits of the space-time separation of correlation effects by studying the crossover from three to two dimensions.

  8. Relativistic electron precipitation at International Space Station: Space weather monitoring by Calorimetric Electron Telescope

    NASA Astrophysics Data System (ADS)

    Kataoka, Ryuho; Asaoka, Yoichi; Torii, Shoji; Terasawa, Toshio; Ozawa, Shunsuke; Tamura, Tadahisa; Shimizu, Yuki; Akaike, Yosui; Mori, Masaki

    2016-05-01

    The charge detector (CHD) of the Calorimetric Electron Telescope (CALET) on board the International Space Station (ISS) has a huge geometric factor for detecting MeV electrons and is sensitive to relativistic electron precipitation (REP) events. During the first 4 months, CALET CHD observed REP events mainly at the dusk to midnight sector near the plasmapause, where the trapped radiation belt electrons can be efficiently scattered by electromagnetic ion cyclotron (EMIC) waves. Here we show that interesting 5-20 s periodicity regularly exists during the REP events at ISS, which is useful to diagnose the wave-particle interactions associated with the nonlinear wave growth of EMIC-triggered emissions.

  9. Electronic Cigarette Topography in the Natural Environment

    PubMed Central

    Morabito, P. N.; Roundtree, K. A.

    2015-01-01

    This paper presents the results of a clinical, observational, descriptive study to quantify the use patterns of electronic cigarette users in their natural environment. Previously published work regarding puff topography has been widely indirect in nature, and qualitative rather than quantitative, with the exception of three studies conducted in a laboratory environment for limited amounts of time. The current study quantifies the variation in puffing behaviors among users as well as the variation for a given user throughout the course of a day. Puff topography characteristics computed for each puffing session by each subject include the number of subject puffs per puffing session, the mean puff duration per session, the mean puff flow rate per session, the mean puff volume per session, and the cumulative puff volume per session. The same puff topography characteristics are computed across all puffing sessions by each single subject and across all subjects in the study cohort. Results indicate significant inter-subject variability with regard to puffing topography, suggesting that a range of representative puffing topography patterns should be used to drive machine-puffed electronic cigarette aerosol evaluation systems. PMID:26053075

  10. [Progress on space oral medicine research under microgravity environment].

    PubMed

    Jing, Chen; Xingqun, Cheng; Xin, Xu; Xuedong, Zhou; Yuqing, Li

    2016-02-01

    As an interdisciplinary of stomatology and space medicine, space oral medicine focuses mainly on oral diseases happened under space environment. With the manned space technology stepping into the new era, space oral medicine has been put under the spotlight. This article will review the historical events on this subject, summarize the newly progress especially on craniomaxillofacial bone, tooth-derived stem cell and oral microbiology researches and still put forward future prospect. PMID:27266206

  11. Reanalysis of relativistic electron phase space density

    NASA Astrophysics Data System (ADS)

    Shprits, Yuri; Chen, Yue; Kondrashov, Dmitri

    In this study we perform a reanalysis of the sparse relativistic electron data using a relatively simple one-dimensional radial diffusion model and a Kalman filtering approach. The results of the reanalysis clearly show pronounced peaks in the electron phase space density (PSD), which can not be explained by the variations in the outer boundary, and can only be produced by a local acceleration processes. The location of the innovation vector shows that local acceleration is most efficient at L* = 5.5. To verify that our results are not affected by the limitations of the satellite orbit and coverage, we performed an "identical twin" experiments with synthetic data specified only at the locations for which CRRES observations are available. Our results indicate that the model with data assimilation can accurately reproduce the underlying structure of the PSD even when data is sparse.

  12. Electro-Mechanical Systems for Extreme Space Environments

    NASA Technical Reports Server (NTRS)

    Mojarradi, Mohammad M.; Tyler, Tony R.; Abel, Phillip B.; Levanas, Greg

    2011-01-01

    Exploration beyond low earth orbit presents challenges for hardware that must operate in extreme environments. The current state of the art is to isolate and provide heating for sensitive hardware in order to survive. However, this protection results in penalties of weight and power for the spacecraft. This is particularly true for electro-mechanical based technology such as electronics, actuators and sensors. Especially when considering distributed electronics, many electro-mechanical systems need to be located in appendage type locations, making it much harder to protect from the extreme environments. The purpose of this paper to describe the advances made in the area of developing electro-mechanical technology to survive these environments with minimal protection. The Jet Propulsion Lab (JPL), the Glenn Research Center (GRC), the Langley Research Center (LaRC), and Aeroflex, Inc. over the last few years have worked to develop and test electro-mechanical hardware that will meet the stringent environmental demands of the moon, and which can also be leveraged for other challenging space exploration missions. Prototype actuators and electronics have been built and tested. Brushless DC actuators designed by Aeroflex, Inc have been tested with interface temperatures as low as 14 degrees Kelvin. Testing of the Aeroflex design has shown that a brushless DC motor with a single stage planetary gearbox can operate in low temperature environments for at least 120 million cycles (measured at motor) if long life is considered as part of the design. A motor control distributed electronics concept developed by JPL was built and operated at temperatures as low as -160 C, with many components still operational down to -245 C. Testing identified the components not capable of meeting the low temperature goal of -230 C. This distributed controller is universal in design with the ability to control different types of motors and read many different types of sensors. The controller

  13. Electrostatic behaviour of materials in a charging space environment

    NASA Astrophysics Data System (ADS)

    Catani, Jean-Pierre; Payan, Denis

    2003-09-01

    Electrostatics is one of major concerns of spacecraft technology. Space is filled with hot and low-density plasma building up high differential voltages resulting in electrostatic discharges, sometimes causing an anomalous behavior of spacecraft electronics. The interaction of the satellite with its environment induces a static charge of the various materials which it is made of. The flow and the evacuation of the charges would require a conductive satellite. Unfortunately, the reality is different and satellites are covered with dielectric materials highly resistant for thermo-optic specific purpose. It is resulting in a absolute charge value of the structure of the satellite and in a differential charge built-up between its components that can be at the origin of electrostatic discharges which consequences can end up in the loss of the satellite itself. Typical anomalies will be reviewed, it will be shown how they can be recognized as consequences of environmental induced discharges. The distribution of charges over different parts of the spacecraft is depending of ambient conditions: plasma temperature and density and sun illumination. Surface and internal charging are possible; they result in dielectric or metal arcing discharges. Understanding of charging phenomena allows us to define mitigation techniques by controlling charging, electromagnetic interference. At last, we will end with the presentation of what it is done in France and in Europe though activities in the domain of space environment in order to take into account problems in a more general context.

  14. Measurements of the thermal plasma environment of the space shuttle

    NASA Astrophysics Data System (ADS)

    Raitt, W. J.; Siskind, D. E.; Banks, P. M.; Williamson, P. R.

    1984-04-01

    The paper presents some initial results on measurements of the thermal plasma environment obtained by a spherical retarding potential analyzer and a Langmuir probe flown on the third space shuttle flight ( STS-3) as part of the NASA Office of Space Science-1 (OSS-1) payload in March 1982. One of the major effects observed is a higher degree of turbulence in the ambient plasma compared to what is observed from similar instruments flown on unmanned satellites. In addition we see the temperature of the thermal electrons elevated to values of 4000-5000 K. Associated with elevated electron temperatures are regions of enhanced plasma density resulting from the appearance of high densities of molecular ions. The thermal plasma data also show clear effects of an induced V × B · L potential at the location of the probes which matches that produced by an L vector linking the probes to the engine nozzles; thereby establishing the prime return current location on the Orbiter. The final observations discussed are the pronounced and complex wake effects resulting both from the main structure of the Orbiter and from the complex shapes of appendages attached to the Orbiter.

  15. MISSE-X: Affordable Space Environment Testing

    NASA Video Gallery

    MISSE–X is a robotically serviceable ISS external facility providing government, industry and academia experimenters with affordable access to space for materials durability testing of potential ...

  16. Space and Atmospheric Environments: From Low Earth Orbits to Deep Space

    NASA Technical Reports Server (NTRS)

    Barth, Janet L.

    2003-01-01

    Natural space and atmospheric environments pose a difficult challenge for designers of technological systems in space. The deleterious effects of environment interactions with the systems include degradation of materials, thermal changes, contamination, excitation, spacecraft glow, charging, radiation damage, and induced background interference. Design accommodations must be realistic with minimum impact on performance while maintaining a balance between cost and risk. The goal of applied research in space environments and effects is to limit environmental impacts at low cost relative to spacecraft cost and to infuse enabling and commercial off-the-shelf technologies into space programs. The need to perform applied research to understand the space environment in a practical sense and to develop methods to mitigate these environment effects is frequently underestimated by space agencies and industry. Applied science research in this area is critical because the complexity of spacecraft systems is increasing, and they are exposed simultaneously to a multitude of space environments.

  17. Review of radiation hardening techniques for EDFAs in space environment

    NASA Astrophysics Data System (ADS)

    Wang, Qian; Tian, CuiPing; Wang, YingYing; Wang, Pu

    2015-03-01

    The damage mechanism and test technology of space radiation environment to space equipment was classified and the radiation protection demand of active fiber for space application was analyzed. The radiation hardening techniques of Ce doping, hydrogen loading and pre-radiation exposure and thermal annealing for Er:Yb co-doped fiber was surveyed.

  18. Current models of the intensely ionizing particle environment in space

    NASA Technical Reports Server (NTRS)

    Adams, James H., Jr.

    1988-01-01

    The Cosmic Ray Effects on MicroElectronics (CREME) model that is currently in use to estimate single event effect rates in spacecraft is described. The CREME model provides a description of the radiation environment in interplanetary space near the orbit of the earth that contains no major deficiencies. The accuracy of the galactic cosmic ray model is limited by the uncertainties in solar modulation. The model for solar energetic particles could be improved by making use of all the data that has been collected on solar energetic particle events. There remain major uncertainties about the environment within the earth's magnetosphere, because of the uncertainties over the charge states of the heavy ions in the anomalous component and solar flares, and because of trapped heavy ions. The present CREME model is valid only at 1 AU, but it could be extended to other parts of the heliosphere. There is considerable data on the radiation environment from 0.2 to 35 AU in the ecliptic plane. This data could be used to extend the CREME model.

  19. Electronics for Low-Temperature Space Operation Being Evaluated

    NASA Technical Reports Server (NTRS)

    Patterson, Richard L.; Hammoud, Ahmad

    2001-01-01

    Electronic components and systems capable of low-temperature operation are needed for many future NASA missions where it is desirable to have smaller, lighter, and cheaper (unheated) spacecraft. These missions include Mars (-20 to -120 C) orbiters, landers, and rovers; Europa (-150 C) oceanic exploratory probes and instrumentation; Saturn (-183 C) and Pluto (-229 C) interplanetary probes. At the present, most electronic equipment can operate down to only -55 C. It would be very desirable to have electronic components that expand the operating temperature range down to -233 C. The successful development of these low-temperature components will eventually allow space probes and onboard electronics to operate in very cold environments (out as far as the planet Pluto). As a result, radioisotope heating units, which are used presently to keep space electronics near room temperature, will be reduced in number or eliminated. The new cold electronics will make spacecraft design and operation simpler, more flexible, more reliable, lighter, and cheaper. Researchers at the NASA Glenn Research Center are evaluating potential commercial off-the- shelf devices and are developing new electronic components that will tolerate operation at low temperatures down to -233 C. This work is being carried out mainly inhouse and also through university grants and commercial contracts. The components include analog-to-digital converters, semiconductor switches, capacitors, dielectric and packaging material, and batteries. For example, the effect of low temperature on the capacitance of three different types of capacitors is shown in the graph. Using these advanced components, system products will be developed, including dc/dc converters, battery charge/discharge management systems, digital control electronics, transducers, and sensor instrumentation.

  20. Spacecraft Materials in the Space Flight Environment: International Space Station - May 2002 to May 2007

    NASA Technical Reports Server (NTRS)

    Golden, John; Lorenz, Mary J.; Alred, John; Koontz, Steven L.; Pedley, Michael

    2008-01-01

    The performance of ISS spacecraft materials and systems on prolonged exposure to the low-Earth orbit (LEO) space flight is reported in this paper. In-flight data, flight crew observations, and the results of ground-based test and analysis directly supporting programmatic and operational decision-making are presented. The space flight environments definitions (both natural and induced) used for ISS design, material selection, and verification testing are shown, in most cases, to be more severe than the actual flight environment accounting for the outstanding performance of ISS as a long mission duration spacecraft. No significant ISS material or system failures have been attributed to spacecraft-environments interactions. Nonetheless, ISS materials and systems performance data is contributing to our understanding of spacecraft material interactions in the spaceflight environment so as to reduce cost and risk for future spaceflight projects and programs. Orbital inclination (51.6o) and altitude (nominally near 360 km) determine the set of natural environment factors affecting the functional life of materials and systems on ISS. ISS operates in an electrically conducting environment (the F2 region of Earth s ionosphere) with well-defined fluxes of atomic oxygen, other charged and neutral ionospheric plasma species, solar UV, VUV, and x-ray radiation as well as galactic cosmic rays, trapped radiation, and solar cosmic rays (1-4). The LEO micrometeoroid and orbital debris environment is an especially important determinant of spacecraft design and operations (5, 6). The magnitude of several environmental factors varies dramatically with latitude and longitude as ISS orbits the Earth (1-4). The high latitude orbital environment also exposes ISS to higher fluences of trapped energetic electrons, auroral electrons, solar cosmic rays, and galactic cosmic rays (1-4) than would be the case in lower inclination orbits, largely as a result of the overall shape and magnitude of

  1. Space environment and lunar surface processes

    NASA Technical Reports Server (NTRS)

    Comstock, G. M.

    1979-01-01

    The development of a general rock/soil model capable of simulating in a self consistent manner the mechanical and exposure history of an assemblage of solid and loose material from submicron to planetary size scales, applicable to lunar and other space exposed planetary surfaces is discussed. The model was incorporated into a computer code called MESS.2 (model for the evolution of space exposed surfaces). MESS.2, which represents a considerable increase in sophistication and scope over previous soil and rock surface models, is described. The capabilities of previous models for near surface soil and rock surfaces are compared with the rock/soil model, MESS.2.

  2. Women's Health Issues in the Space Environment

    NASA Technical Reports Server (NTRS)

    Jennings, Richard T.

    1999-01-01

    Women have been an integral part of US space crews since Sally Ride's mission in 1983, and a total of 40 women have been selected as US astronauts. The first Russian female cosmonaut flew in 1963. This presentation examines the health care and reproductive aspects of flying women in space. In addition, the reproductive implications of delaying one's childbearing for an astronaut career and the impact of new technology such as assisted reproductive techniques are examined. The reproductive outcomes of the US female astronauts who have become pregnant following space flight exposure are also presented. Since women have gained considerable operational experience on the Shuttle, Mir and during EVA, the unique operational considerations for preflight certification, menstruation control and hygiene, contraception, and urination are discussed. Medical and surgical implications for women on long-duration missions to remote locations are still evolving, and enabling technologies for health care delivery are being developed. There has been considerable progress in the development of microgravity surgical techniques, including laparoscopy, thoracoscopy, and laparotomy. The concepts of prevention of illness, conversion of surgical conditions to medically treatable conditions and surgical intervention for women on long duration space flights are considered.

  3. Power electronic applications for Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Pickrell, Roy L.; Lazbin, Igor

    1990-01-01

    NASA plans to orbit a permanently manned space station in the late 1990s, which requires development and assembly of a photovoltaic (PV) power source system to supply up to 75 kW of electrical power average during the orbital period. The electrical power requirements are to be met by a combination of PV source, storage, and control elements for the sun and eclipse periods. The authors discuss the application of power electronics and controls to manage the generation, storage, and distribution of power to meet the station loads, as well as the computer models used for analysis and simulation of the PV power system. The requirements for power source integrated controls to adjust storage charge power during the insolation period current limiting, breaker interrupt current values, and the electrical fault protection approach are defined. Based on these requirements, operating concepts have been defined which then become drivers for specific system and element design.

  4. Overview of fiber optics in the natural space environment

    NASA Technical Reports Server (NTRS)

    Barnes, C.; Dorsky, L.; Johnston, A.; Bergman, L.; Stassinopoulos, E.

    1991-01-01

    The potential applications of fiber-optic (FO) systems in spacecraft which will be exposed to the space radiation environment are discussed in view of tests conducted aboard the Long-Duration Exposure Facility and the Comet Rendezvous and Asteroid Flyby spacecraft. Attention is given to anticipated trends in the use of FO in spacecraft communications systems. The natural space radiation environment is noted to be far more benign than the military space environment, which encompasses displacement-damage effects due to significant neutron influences.

  5. The Living With a Star Space Environment Testbed Program

    NASA Technical Reports Server (NTRS)

    Barth, Janet; LaBel, Kenneth; Day, John H. (Technical Monitor)

    2001-01-01

    NASA has initiated the Living with a Star (LWS) Program to develop the scientific understanding to address the aspects of the Connected Sun-Earth system that affects life and society. The Program Architecture includes science missions, theory and modeling and Space Environment Testbeds (SET). This current paper discusses the Space Environment Testbeds. The goal of the SET program is to improve the engineering approach to accomodate and/or mitigate the effects of solar variability on spacecraft design and operations. The SET Program will infuse new technologies into the space programs through collection of data in space and subsequent design and validation of technologies. Examples of these technologies are cited and discussed.

  6. Software Process Assurance for Complex Electronics (SPACE)

    NASA Technical Reports Server (NTRS)

    Plastow, Richard A.

    2007-01-01

    Complex Electronics (CE) are now programmed to perform tasks that were previously handled in software, such as communication protocols. Many of the methods used to develop software bare a close resemblance to CE development. For instance, Field Programmable Gate Arrays (FPGAs) can have over a million logic gates while system-on-chip (SOC) devices can combine a microprocessor, input and output channels, and sometimes an FPGA for programmability. With this increased intricacy, the possibility of software-like bugs such as incorrect design, logic, and unexpected interactions within the logic is great. Since CE devices are obscuring the hardware/software boundary, we propose that mature software methodologies may be utilized with slight modifications in the development of these devices. Software Process Assurance for Complex Electronics (SPACE) is a research project that looks at using standardized S/W Assurance/Engineering practices to provide an assurance framework for development activities. Tools such as checklists, best practices and techniques can be used to detect missing requirements and bugs earlier in the development cycle creating a development process for CE that will be more easily maintained, consistent and configurable based on the device used.

  7. Manned testing in a simulated space environment

    NASA Astrophysics Data System (ADS)

    Fender, Donna L.

    1992-11-01

    A view of the facility and operational requirements involved in performing a manned thermal vacuum test is presented. The requirements fall into two major categories. The first category deals with placing the suited crewmen in a hazardous environment and assuring their safety. The second category deals with the constraints and special requirements involved with a suited crewman operating flight hardware in a 1-G environment. Design areas that deal with man rating a chamber, including fire suppression, emergency repress, emergency power, backups, reliable instrumentation and data systems, communications, television monitoring, biomedical monitoring, material compatibilities, and equipment supporting the Extravehicular Mobility Unit (EMU) are discussed. The operational issues that are peculiar to manned testing such as test rules, test procedures, test protocol, emergency drills, availability of hyperbaric facilities, test team training and certification engineering concerns for a safe mechanical and instrumentation buildup, hazard analysis, and Failure Modes and Effects Analysis are discussed. The constraints and special requirements involved with a suited crewman operating flight hardware in a 1-G environment are addressed.

  8. Microorganisms and biomolecules in space hard environment

    NASA Technical Reports Server (NTRS)

    Horneck, G.

    1981-01-01

    Microorganisms and biomolecules exposed to space vacuum and to different intensities of selected wavelengths of solar ultraviolet radiation is studied. The influence of these factors, applied singly or simultaneously, on the integrity of microbial systems and biomolecules is measured. Specifically, this experiment will study in Bacillus subtilis spores (1) disturbances in subsequent germination, outgrowth, and colony formation; (2) photochemical reactions of the DNA and protein in vivo and in vitro and their role in biological injury; and (3) the efficiency of repair processes in these events.

  9. Relating space radiation environments to risk estimates

    SciTech Connect

    Curtis, S.B.

    1991-10-01

    This lecture will provide a bridge from the physical energy or LET spectra as might be calculated in an organ to the risk of carcinogenesis, a particular concern for extended missions to the moon or beyond to Mars. Topics covered will include (1) LET spectra expected from galactic cosmic rays, (2) probabilities that individual cell nuclei in the body will be hit by heavy galactic cosmic ray particles, (3) the conventional methods of calculating risks from a mixed environment of high and low LET radiation, (4) an alternate method which provides certain advantages using fluence-related risk coefficients (risk cross sections), and (5) directions for future research and development of these ideas.

  10. System Engineering Issues for Avionics Survival in the Space Environment

    NASA Technical Reports Server (NTRS)

    Pavelitz, Steven

    1999-01-01

    This paper examines how the system engineering process influences the design of a spacecraft's avionics by considering the space environment. Avionics are susceptible to the thermal, radiation, plasma, and meteoroids/orbital debris environments. The environment definitions for various spacecraft mission orbits (LEO/low inclination, LEO/Polar, MEO, HEO, GTO, GEO and High ApogeeElliptical) are discussed. NASA models and commercial software used for environment analysis are reviewed. Applicability of technical references, such as NASA TM-4527 "Natural Orbital Environment Guidelines for Use in Aerospace Vehicle Development" is discussed. System engineering references, such as the MSFC System Engineering Handbook, are reviewed to determine how the environments are accounted for in the system engineering process. Tools and databases to assist the system engineer and avionics designer in addressing space environment effects on avionics are described and usefulness assessed.

  11. Kapton pyrolysis, the space environment and wiring requirements

    NASA Technical Reports Server (NTRS)

    Ferguson, Dale C.

    1994-01-01

    New Low Earth Orbit (LEO) requirements of space environment wiring are compared with traditional requirements. The pyrolysis of Kapton is reviewed for the LeRc vacuum chamber and the 1989 SSF. SEEB modeling of Kapton pyrolysis is also presented.

  12. Space Weather Monitoring for ISS Space Environments Engineering and Crew Auroral Observations

    NASA Technical Reports Server (NTRS)

    Minow, Joseph; Pettit, Donald R.; Hartman, William A.

    2012-01-01

    Today s presentation describes how real time space weather data is used by the International Space Station (ISS) space environments team to obtain data on auroral charging of the ISS vehicle and support ISS crew efforts to obtain auroral images from orbit. Topics covered include: Floating Potential Measurement Unit (FPMU), . Auroral charging of ISS, . Real ]time space weather monitoring resources, . Examples of ISS auroral charging captured from space weather events, . ISS crew observations of aurora.

  13. Protection of the Space Environment: The First Small Steps

    NASA Astrophysics Data System (ADS)

    Williamson, M.

    The exploration of the space environment - by robotic and manned missions - is a natural extension of mankind's desire to explore his own planet. Likewise, the development of the space environment - for industry, commerce and tourism - is a natural extension of our current business and domestic environment. Unfortunately, it appears that our ability to pollute, degrade and even destroy aspects of the space environment is also an extension of an ability we have developed and practised here on Earth. This paper reviews the evidence of mankind's pollution of the space environment - which includes the planetary bodies - in the first 45 years of the Space Age, and extrapolates the potential for further degradation into its second half-century. It considers the future development of both scientific exploration and commercial exploitation - in orbit and on the surface of the planetary bodies - and the possible detrimental effects. In presenting the case for protection of the space environment, the paper makes recommendations concerning the first steps towards a solution to the problem. Among other things, it calls for the formation of an international consultative body, to consider the issues relevant to `Protection of the Space Environment' and to raise awareness of the subject among the growing body of space professionals and practitioners. It also recommends consideration of a `set of guidelines' or `code of practice' as a precursor to more formal policies or legislation. In doing so, however, it is careful to recognise the need to strike a balance between unbridled exploration and development, and a stifling regime of rules and regulations. The discussion of this subject requires a good deal more collective knowledge, understanding and maturity than has been evident in similar discussions regarding the Earth's environment. At present, that knowledge resides largely within the professional space community. Thus there is also a need for promulgation, both within and

  14. Natural environment support guidelines for Space Shuttle tests and operations

    NASA Technical Reports Server (NTRS)

    Carter, E. A.; Brown, S. C.

    1974-01-01

    The present work outlines the general concept as to how natural environment guidelines will be developed for Space Shuttle activities. The following six categories that might need natural environment support are single out: development tests; preliminary operations and prelaunch; launch to orbit; orbital mission and operations; deorbit, entry, and landing; ferry flights. An example of detailed event requirements for decisions to launch is given. Some artist's conceptions of proposed launch complexes at Kennedy Space Center and Vandenberg AFB are shown.

  15. The Living With a Star Space Environment Testbeds

    NASA Astrophysics Data System (ADS)

    Brewer, D.; Barth, J.; Label, K.

    The Living With a Star (LWS) Space Environment Testbeds (SET) are a series of projects that contain investigations that collect data in space and use it to provide products that improve the engineering approach to accommodate and/or mitigate the effects of solar variability on spacecraft design and operations. The improvements reduce requirements for design and operations margins to account for the uncertainties in the space environment and its effects. Reducing the requirements will increase the payload fraction, permit the use of a smaller launch vehicle (thereby reducing mission cost), and/or enable routine operations in new segments of the environment (such as middle Earth orbit, the region from 2000 km to 10,000 km) at costs similar to those for operations below 2000 km. A new SET project starts about very two years when investigations are selected. Five categories of investigations included in SET projects are: (1) Characterization of the space environment in the presence of a spacecraft; (2) Definition of the mechanisms for materials' degradation and the performance characterization of materials designed for shielding from ionizing radiation; (3) Accommodation and/or mitigation of space environment effects for detectors/sensors; (4) Performance improvement methodology for microelectronics used in space; and, (5) Accommodation and/or mitigation of charging/discharging effects on spacecraft and spacecraft components. All SET projects use secondary access to space and partnering to leverage resources. An overview of the SET segment of the LWS program will be presented.

  16. Neuronal plasticity: adaptation and readaptation to the environment of space

    NASA Technical Reports Server (NTRS)

    Correia, M. J.

    1998-01-01

    While there have been few documented permanent neurological changes resulting from space travel, there is a growing literature which suggests that neural plasticity sometimes occurs within peripheral and central vestibular pathways during and following spaceflight. This plasticity probably has adaptive value within the context of the space environment, but it can be maladaptive upon return to the terrestrial environment. Fortunately, the maladaptive responses resulting from neuronal plasticity diminish following return to earth. However, the literature suggests that the longer the space travel, the more difficult the readaptation. With the possibility of extended space voyages and extended stays on board the international space station, it seems worthwhile to review examples of plastic vestibular responses and changes in the underlying neural substrates. Studies and facilities needed for space station investigation of plastic changes in the neural substrates are suggested. Copyright 1998 Elsevier Science B.V.

  17. RESCU: A real space electronic structure method

    NASA Astrophysics Data System (ADS)

    Michaud-Rioux, Vincent; Zhang, Lei; Guo, Hong

    2016-02-01

    In this work we present RESCU, a powerful MATLAB-based Kohn-Sham density functional theory (KS-DFT) solver. We demonstrate that RESCU can compute the electronic structure properties of systems comprising many thousands of atoms using modest computer resources, e.g. 16 to 256 cores. Its computational efficiency is achieved from exploiting four routes. First, we use numerical atomic orbital (NAO) techniques to efficiently generate a good quality initial subspace which is crucially required by Chebyshev filtering methods. Second, we exploit the fact that only a subspace spanning the occupied Kohn-Sham states is required, and solving accurately the KS equation using eigensolvers can generally be avoided. Third, by judiciously analyzing and optimizing various parts of the procedure in RESCU, we delay the O (N3) scaling to large N, and our tests show that RESCU scales consistently as O (N2.3) from a few hundred atoms to more than 5000 atoms when using a real space grid discretization. The scaling is better or comparable in a NAO basis up to the 14,000 atoms level. Fourth, we exploit various numerical algorithms and, in particular, we introduce a partial Rayleigh-Ritz algorithm to achieve efficiency gains for systems comprising more than 10,000 electrons. We demonstrate the power of RESCU in solving KS-DFT problems using many examples running on 16, 64 and/or 256 cores: a 5832 Si atoms supercell; a 8788 Al atoms supercell; a 5324 Cu atoms supercell and a small DNA molecule submerged in 1713 water molecules for a total 5399 atoms. The KS-DFT is entirely converged in a few hours in all cases. Our results suggest that the RESCU method has reached a milestone of solving thousands of atoms by KS-DFT on a modest computer cluster.

  18. Gravity Sensor Plasticity in the Space Environment

    NASA Technical Reports Server (NTRS)

    Ross, Muriel D.

    1996-01-01

    The ability of the brain to learn from experience and to adapt to new environments is recognized to be profound. This ability, called 'neural plasticity,' depends directly on properties of neurons (nerve cells) that permit them to change in dimension, sprout new parts called spines, change the shape and/or size of existing parts, and to generate, alter, or delete synapses. (Synapses are communication sites between neurons.) These neuronal properties are most evident during development, when evolution guides the laying down of a general plan of the nervous system. However, once a nervous system is established, experience interacts with cellular and genetic mechanisms and the internal milieu to produce unique neuronal substrates that define each individual. The capacity for experience-related neuronal growth in the brain, as measured by the potential for synaptogenesis, is speculated to be in the trillions of synapses, but the range of increment possible for any one part of the nervous system is unknown. The question has been whether more primitive endorgans such as gravity sensors of the inner ear have a capacity for adaptive change, since this is a form of learning from experience.

  19. Effects of space radiation on electronic microcircuits

    NASA Technical Reports Server (NTRS)

    Kolasinski, W. A.

    1989-01-01

    The single event effects or phenomena (SEP), which so far have been observed as events falling on one or another of the SE classes: Single Event Upset (SEU), Single Event Latchup (SEL) and Single Event Burnout (SEB), are examined. Single event upset is defined as a lasting, reversible change in the state of a multistable (usually bistable) electronic circuit such as a flip-flop or latch. In a computer memory, SEUs manifest themselves as unexplained bit flips. Since latchup is in general caused by a single event of short duration, the single event part of the SEL term is superfluous. Nevertheless, it is used customarily to differentiate latchup due to a single heavy charged particle striking a sensitive cell from more ordinary kinds of latchup. Single event burnout (SEB) refers usually to total instantaneous failure of a power FET when struck by a single particle, with the device shorting out the power supply. An unforeseen failure of these kinds can be catastrophic to a space mission, and the possibilities are discussed.

  20. Space Weather Monitoring for ISS Space Environments Engineering and Crew Auroral Observations

    NASA Technical Reports Server (NTRS)

    Minow, Joseph I.; Pettit, Donald R.; Hartman, William A.

    2012-01-01

    The awareness of potentially significant impacts of space weather on spaceand ground ]based technological systems has generated a strong desire in many sectors of government and industry to effectively transform knowledge and understanding of the variable space environment into useful tools and applications for use by those entities responsible for systems that may be vulnerable to space weather impacts. Essentially, effectively transitioning science knowledge to useful applications relevant to space weather has become important. This talk will present proven methodologies that have been demonstrated to be effective, and how in the current environment those can be applied to space weather transition efforts.

  1. Space Photovoltaic Research and Technology 1985: High Efficiency, Space Environment, and Array Technology

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The seventh NASA Conference on Space Photovoltaic Research and Technology was held at NASA Lewis Research Center, Cleveland, Ohio, from 30 April until 2 May 1985. Its purpose was to assess the progress made, the problems remaining, and future strategy for space photovoltaic research. Particular emphasis was placed on high efficiency, space environment, and array technology.

  2. The Living With a Star Space Environment Testbed Experiments

    NASA Technical Reports Server (NTRS)

    Xapsos, Michael A.

    2014-01-01

    The focus of the Living With a Star (LWS) Space Environment Testbed (SET) program is to improve the performance of hardware in the space radiation environment. The program has developed a payload for the Air Force Research Laboratory (AFRL) Demonstration and Science Experiments (DSX) spacecraft that is scheduled for launch in August 2015 on the SpaceX Falcon Heavy rocket. The primary structure of DSX is an Evolved Expendable Launch Vehicle (EELV) Secondary Payload Adapter (ESPA) ring. DSX will be in a Medium Earth Orbit (MEO). This oral presentation will describe the SET payload.

  3. The Living With a Star Program Space Environment Testbed

    NASA Technical Reports Server (NTRS)

    Barth, Janet; Day, John H. (Technical Monitor)

    2001-01-01

    This viewgraph presentation describes the objective, approach, and scope of the Living With a Star (LWS) program at the Marshall Space Flight Center. Scientists involved in the project seek to refine the understanding of space weather and the role of solar variability in terrestrial climate change. Research and the development of improved analytic methods have led to increased predictive capabilities and the improvement of environment specification models. Specifically, the Space Environment Testbed (SET) project of LWS is responsible for the implementation of improved engineering approaches to observing solar effects on climate change. This responsibility includes technology development, ground test protocol development, and the development of a technology application model/engineering tool.

  4. Physical phenomena related to crystal growth in the space environment

    NASA Technical Reports Server (NTRS)

    Chu, T. L.

    1973-01-01

    The mechanism of crystal growth which may be affected by the space environment was studied. Conclusions as to the relative technical and scientific advantages of crystal growth in space over earth bound growth, without regard to economic advantage, were deduced. It was concluded that the crucibleless technique will most directly demonstrate the unique effects of the greatly reduced gravity in the space environment. Several experiments, including crucibleless crystal growth using solar energy and determination of diffusion coefficients of common dopants in liquid silicon were recommended.

  5. ISS External Contamination Environment for Space Science Utilization

    NASA Technical Reports Server (NTRS)

    Soares, Carlos; Mikatarian, Ron; Steagall, Courtney; Huang, Alvin; Koontz, Steven; Worthy, Erica

    2014-01-01

    (1) The International Space Station is the largest and most complex on-orbit platform for space science utilization in low Earth orbit, (2) Multiple sites for external payloads, with exposure to the associated natural and induced environments, are available to support a variety of space science utilization objectives, (3) Contamination is one of the induced environments that can impact performance, mission success and science utilization on the vehicle, and (4)The ISS has been designed, built and integrated with strict contamination requirements to provide low levels of induced contamination on external payload assets.

  6. Microgravity Acceleration Environment of the International Space Station (panel)

    NASA Technical Reports Server (NTRS)

    DeLombard, Richard; Hrovat, Kenneth; Kelly, Eric; McPherson, Kevin; Foster, William M.; Schafer, Craig P.

    2001-01-01

    This paper examines the microgravity environment provided to the early science experiments by the International Space Station vehicle which is under construction. The microgravity environment will be compared with predicted levels for this stage of assembly. Included are initial analyses of the environment and preliminary identification of some sources of accelerations. Features of the operations of the accelerometer instruments, the data processing system, and data dissemination to users are also described.

  7. Teamwork in high-risk environments analogous to space

    NASA Technical Reports Server (NTRS)

    Kanki, Barbara G.

    1990-01-01

    Mountaineering expeditions combine a number of factors which make them potentially good analogs to the planetary exploration facet of long-duration space missions. A study of mountain climbing teams was conducted in order to evaluate the usefulness of the environment as a space analog and to specifically identify the factors and issues surrounding teamwork and 'successful' team performance in two mountaineering environments. This paper focuses on social/organizational factors, including team size and structure, leadership styles and authority structure which were found in the sample of 22 climb teams (122 individuals). The second major issue discussed is the construction of a valid performance measure in this high-risk environment.

  8. Space and planetary environment criteria guidelines for use in space vehicle development, 1971 revision

    NASA Technical Reports Server (NTRS)

    Smith, R. E. (Editor)

    1971-01-01

    A consolidation of natural environment data is presented for use as design criteria guidelines in space and planetary exploration vehicle development programs. In addition to information in the disciplinary areas of aeronomy, radiation, geomagnetism, astrodynamic constants, and meteoroids for the earth's environment above 90 kilometers, interplanetary space, and the planetary environments, the upper atmosphere model currently recommended for use at MSFC is discussed in detail.

  9. The Space Electronics Division: Research for Today and Tomorrow

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This video gives an overview of work being done by the different branches of the Space Electronics Division at LeRC. The video highlights electron beam, solid state, high speed circuit design, and high frequency communication research.

  10. Protection of the space environment: the first small steps

    NASA Astrophysics Data System (ADS)

    Williamson, Mark

    2004-01-01

    The development of the space environment - for industry, commerce and tourism - is a natural extension of our current business and domestic agenda. Unfortunately, this brings with it the ability to pollute, degrade and even destroy aspects of the space environment. This paper briefly reviews the evidence of mankind's pollution of the space environment in the first 45 years of the Space Age, and extrapolates the potential for further degradation into its second half-century. It also makes recommendations concerning the first steps towards a solution to the problem, including the formation of an international consultative body and consideration of a `set of guidelines' or `code of practice' as a precursor to more formal policies or legislation.

  11. An HLA based design of space system simulation environment

    NASA Astrophysics Data System (ADS)

    Li, Yinghua; Li, Yong; Liu, Jie

    2007-06-01

    Space system simulation is involved in many application fields, such as space remote sensing and space communication, etc. A simulation environment which can be shared by different space system simulation is needed. Two rules, called object template towing and hierarchical reusability, are proposed. Based on these two rules, the architecture, the network structure and the function structure of the simulation environment are designed. Then, the mechanism of utilizing data resources, inheriting object models and running simulation systems are also constructed. These mechanisms make the simulation objects defined in advance be easily inherited by different HLA federates, the fundamental simulation models be shared by different simulation systems. Therefore, the simulation environment is highly universal and reusable.

  12. Modeling Ionosphere Environments: Creating an ISS Electron Density Tool

    NASA Technical Reports Server (NTRS)

    Gurgew, Danielle N.; Minow, Joseph I.

    2011-01-01

    The International Space Station (ISS) maintains an altitude typically between 300 km and 400 km in low Earth orbit (LEO) which itself is situated in the Earth's ionosphere. The ionosphere is a region of partially ionized gas (plasma) formed by the photoionization of neutral atoms and molecules in the upper atmosphere of Earth. It is important to understand what electron density the spacecraft is/will be operating in because the ionized gas along the ISS orbit interacts with the electrical power system resulting in charging of the vehicle. One instrument that is already operational onboard the ISS with a goal of monitoring electron density, electron temperature, and ISS floating potential is the Floating Potential Measurement Unit (FPMU). Although this tool is a valuable addition to the ISS, there are limitations concerning the data collection periods. The FPMU uses the Ku band communication frequency to transmit data from orbit. Use of this band for FPMU data runs is often terminated due to necessary observation of higher priority Extravehicular Activities (EVAs) and other operations on ISS. Thus, large gaps are present in FPMU data. The purpose of this study is to solve the issue of missing environmental data by implementing a secondary electron density data source, derived from the COSMIC satellite constellation, to create a model of ISS orbital environments. Extrapolating data specific to ISS orbital altitudes, we model the ionospheric electron density along the ISS orbit track to supply a set of data when the FPMU is unavailable. This computer model also provides an additional new source of electron density data that is used to confirm FPMU is operating correctly and supplements the original environmental data taken by FPMU.

  13. Modeling of space environment impact on nanostructured materials. General principles

    NASA Astrophysics Data System (ADS)

    Voronina, Ekaterina; Novikov, Lev

    2016-07-01

    In accordance with the resolution of ISO TC20/SC14 WG4/WG6 joint meeting, Technical Specification (TS) 'Modeling of space environment impact on nanostructured materials. General principles' which describes computer simulation methods of space environment impact on nanostructured materials is being prepared. Nanomaterials surpass traditional materials for space applications in many aspects due to their unique properties associated with nanoscale size of their constituents. This superiority in mechanical, thermal, electrical and optical properties will evidently inspire a wide range of applications in the next generation spacecraft intended for the long-term (~15-20 years) operation in near-Earth orbits and the automatic and manned interplanetary missions. Currently, ISO activity on developing standards concerning different issues of nanomaterials manufacturing and applications is high enough. Most such standards are related to production and characterization of nanostructures, however there is no ISO documents concerning nanomaterials behavior in different environmental conditions, including the space environment. The given TS deals with the peculiarities of the space environment impact on nanostructured materials (i.e. materials with structured objects which size in at least one dimension lies within 1-100 nm). The basic purpose of the document is the general description of the methodology of applying computer simulation methods which relate to different space and time scale to modeling processes occurring in nanostructured materials under the space environment impact. This document will emphasize the necessity of applying multiscale simulation approach and present the recommendations for the choice of the most appropriate methods (or a group of methods) for computer modeling of various processes that can occur in nanostructured materials under the influence of different space environment components. In addition, TS includes the description of possible

  14. Capabilities of the Natural Environments Branch at NASA's Marshall Space Flight Center, Revised 2009

    NASA Technical Reports Server (NTRS)

    Edwards, David L.; Suggs, Rob; Roberts, Barry C.; Cooke, William J.

    2009-01-01

    The Natural Environment Branch at NASA's Marshall Space Flight Center (MSFC) has the responsibility to provide natural environments engineering support to programs and projects. The Natural Environments Branch is responsible for natural environments definitions, modeling, database development, and analytical assessments of effects. Natural Environments Branch personnel develop requirements for flight projects and provide operational support for space and launch vehicle systems. To accomplish these responsibilities, models and analytical tools have been developed in the areas of planetary atmospheres, meteoroids, ionizing radiation, plasmas and ionospheres, magnetic and gravitational fields, spacecraft charging modeling, and radiation effects on electronic parts. This paper will build on a previous paper published in 2006 and provide updated descriptions of the capabilities within the Natural Environments Branch1. Updates describing improvements and new releases of several analytical tools and models will be presented. Separate sections will specifically describe modifications in the Meteoroid Engineering Model (MEM), and the Marshall Solar Activity Future Estimation (MSAFE) capabilities.

  15. Recent Results of NASA's Space Environments and Effects Program

    NASA Technical Reports Server (NTRS)

    Minor, Jody L.; Brewer, Dana S.

    1998-01-01

    The Space Environments and Effects (SEE) Program is a multi-center multi-agency program managed by the NASA Marshall Space Flight Center. The program evolved from the Long Duration Exposure Facility (LDEF), analysis of LDEF data, and recognition of the importance of the environments and environmental effects on future space missions. It is a very comprehensive and focused approach to understanding the space environments, to define the best techniques for both flight and ground-based experimentation, to update the models which predict both the environments and the environmental effects on spacecraft, and finally to ensure that this information is properly maintained and inserted into spacecraft design programs. Formal funding of the SEE Program began initially in FY95. A NASA Research Announcement (NRA) solicited research proposals in the following categories: 1) Engineering environment definitions; 2) Environments and effects design guidelines; 3) Environments and effects assessment models and databases; and, 4) Flight/ground simulation/technology assessment data. This solicitation resulted in funding for eighteen technology development activities (TDA's). This paper will present and describe technical results rom the first set of TDA's of the SEE Program. It will also describe the second set of technology development activities which are expected to begin in January 1998. These new technology development activities will enable the SEE Program to start numerous new development activities in support of mission customer needs.

  16. Development and testing of coatings for orbital space radiation environments.

    PubMed

    Pellicori, Samuel F; Martinez, Carol L; Hausgen, Paul; Wilt, David

    2014-02-01

    Specific coating processes and materials were investigated in the quest to develop multilayer coatings with greater tolerance to space radiation exposure. Ultraviolet reflection (UVR) and wide-band antireflection (AR) multilayer coatings were deposited on solar cell covers and test substrates and subsequently exposed to simulated space environments and also flown on the Materials International Space Station Experiment-7 (MISSE-7) to determine their space environment stability. Functional solar cells integrated with these coatings underwent simulated UV and MISSE-7 low earth orbit flight exposure. The effects of UV, proton, and atomic oxygen exposure on coatings and on assembled solar cells as related to the implemented deposition processes and material compositions were small. The UVR/AR coatings protected flexible polymer substrate materials that are intended for future flexible multijunction cell arrays to be deployed from rolls. Progress was made toward developing stable and protective coatings for extended space-mission applications. Test results are presented. PMID:24514237

  17. Workshop on Mercury: Space Environment, Surface, and Interior

    NASA Technical Reports Server (NTRS)

    2001-01-01

    This volume contains abstracts that have been accepted for presentation at the Workshop on Mercury: Space Environment, Surface, and Interior, October 4-5, 2001. The Scientific Organizing Committee consisted of Mark Robinson (Northwestern University), Marty Slade (Jet Propulsion Laboratory), Jim Slavin (NASA Goddard Space Flight Center), Sean Solomon (Carnegie Institution), Ann Sprague (University of Arizona), Paul Spudis (Lunar and Planetary Institute), G. Jeffrey Taylor (University of Hawai'i), Faith Vilas (NASA Johnson Space Center), Meenakshi Wadhwa (The Field Museum), and Thomas Watters (National Air and Space Museum). Logistics, administrative, and publications support were provided by the Publications and Program Services Departments of the Lunar and Planetary Institute.

  18. Providing controlled environments for plant growth in space.

    PubMed

    Bula, R J; Ignatius, R W

    1996-12-01

    Providing a controlled environment for growth of plants in a space environment involves development of unique technologies for the various subsystems of the plant growing facility. These subsystems must be capable of providing the desired environmental control within the operational constraints of currently available space vehicles, primarily the US Space Shuttle or the Russian Space Station, MIR. These constraints include available electrical power, limited total payload mass, and limited volume of the payload. In addition, the space hardware must meet safety requirements for a man-rated space vehicle. The ASTROCULTURE (TM) space-based plant growth unit provides control of temperature, humidity, and carbon dioxide concentration of the plant chamber air. A light emitting diode (LED) unit provides red and blue photons with a total intensity adjustable from 0 to 500 micromoles m-2 s-1. Ethylene released by the plant material is removed with a non-consumable ethylene removable unit. A porous tube and rooting matrix subsystem is used to supply water and nutrients to the plants. The ASTROCULTURE(TM) flight unit is sized to be accommodated in a single middeck locker of the US Space Shuttle, the SPACEHAB module, and with slight modification in the SPACELAB module. The environmental control capabilities of the subsystems used in the ASTROCULTURE(TM) flight unit have been validated in a microgravity environment during five US Space Shuttle missions, including two with plants. The unique environmental control technologies developed for the space-based plant growth facility can be used to enhance the environmental control capabilities of terrestrial controlled environment plant chambers. PMID:11541567

  19. Space and planetary environment criteria guidelines for use in space vehicle development. Volume 1: 1982 revision

    NASA Technical Reports Server (NTRS)

    Smith, R. E. (Compiler); West, G. S. (Compiler)

    1983-01-01

    Guidelines on space and planetary environment criteria for use in space vehicle development are provided. Information is incorporated in the disciplinary areas of atmospheric and ionospheric properties, radiation, geomagnetic field, astrodynamic constants, and meteoroids for the Earth's atmosphere above 90 km, interplanetary space, and the atmosphere and surfaces (when available) of the Moon and the planets (other than Earth) of this solar system. The Sun, Terrestrial Space, the Moon, Mercury, Venus, and Mars are covered.

  20. Underestimated role of the secondary electron emission in the space

    NASA Astrophysics Data System (ADS)

    Nemecek, Zdenek; Richterova, Ivana; Safrankova, Jana; Pavlu, Jiri; Vaverka, Jakub; Nouzak, Libor

    2016-07-01

    Secondary electron emission (SEE) is one of many processes that charges surfaces of bodies immersed into a plasma. Until present, a majority of considerations in theories and experiments is based on the sixty year old description of an interaction of planar metallic surfaces with electrons, thus the effects of a surface curvature, roughness, presence of clusters as well as an influence of the material conductance on different aspects of this interaction are neglected. Dust grains or their clusters can be frequently found in many space environments - interstellar clouds, atmospheres of planets, tails of comets or planetary rings are only typical examples. The grains are exposed to electrons of different energies and they can acquire positive or negative charge during this interaction. We review the progress in experimental investigations and computer simulations of the SEE from samples relevant to space that was achieved in course of the last decade. We present a systematic study of well-defined systems that starts from spherical grains of various diameters and materials, and it continues with clusters consisting of different numbers of small spherical grains that can be considered as examples of real irregularly shaped space grains. The charges acquired by investigated objects as well as their secondary emission yields are calculated using the SEE model. We show that (1) the charge and surface potential of clusters exposed to the electron beam are influenced by the number of grains and by their geometry within a particular cluster, (2) the model results are in an excellent agreement with the experiment, and (3) there is a large difference between charging of a cluster levitating in the free space and that attached to a planar surface. The calculation provides a reduction of the secondary electron emission yield of the surface covered by dust clusters by a factor up to 1.5 with respect to the yield of a smooth surface. (4) These results are applied on charging of

  1. Space Environment Data Acquisition Equipment -Attached Payload (SEDA-AP) on the ISS -"Kibo" Exposed Facility

    NASA Astrophysics Data System (ADS)

    Koga, Kiyokazu; Matsumoto, Haruhisa; Kimoto, Yugo; Obara, Takahiro; Goka, Tateo

    To support future space activities, it is very important to acquire space environmental data related to space radiation degradation of space parts and materials and spacecraft anomalies. Such data are useful for spacecraft design and manned space activity. On several satellite of the Japan Aerospace Exploration Agency (JAXA) since the Engineering Test Satellite-V (ETS-V), Technical Data Acquisition Equipment (TEDA) and Space Environment Data Acquisition Equipment (SEDA) have been installed for obtaining the data described above. SEDA-Attached Payload (AP) was mounted on Japanese experimental module, "Kibo" , at International Space Station (ISS) to take continuous measurements of the 400 kilometres altitude space station's tra-jectory for a period of around 3 years. SEDA-AP comprises common bus equipment supporting launch, RMS handling, the power/communication interface with JEM-EF, an extendible mast that extends the neutron monitor sensor 1 m separate from the bus structure, and equipment that measures space environment data. SEDA-AP has been fitted with 8 kinds of instruments. It will continuously and simultaneously measure neutrons, heavy ions, plasma, high-energy electrons and protons, atomic oxygen, space debris and dusts, etc. Furthermore, by exposing electronic devices and materials directory to the space environment, it will examine how they are affected by the environment. SEDA-AP was lanced on July 16 in 2009, and attached to EF of "Kibo" on July 25 using the robot arm of "Kibo". Initial checkout was started on Au-gust 4 and successfully ended on September 17. This paper will report the mission objectives, instrumentation, and current status of SEDA-AP.

  2. NASA's Space Environments and Effects Program: Technology for the New Millennium

    NASA Technical Reports Server (NTRS)

    Hardage, Donna M.; Pearson, Steven D.

    2000-01-01

    Current trends in spacecraft development include the use of advanced technologies while maintaining the "faster, better, cheaper" philosophy. Spacecraft designers are continually designing with smaller and faster electronics as well as lighter and thinner materials providing better performance, lower weight, and ultimately lower costs. Given this technology trend, spacecraft will become increasingly susceptible to the harsh space environments, causing damaging or even disabling effects on space systems. NASA's Space Environments and Effects (SEE) Program defines the space environments and provides advanced technology development to support the design, development, and operation of spacecraft systems that will accommodate or mitigate effects due to the harsh space environments. This Program provides a comprehensive and focused approach to understanding the space environment, to define the best techniques for both flight and ground-based experimentation, to update the models which predict both the environments and the environmental effects on spacecraft, and finally to ensure that this multitudinous information is properly maintained and inserted into spacecraft design programs. A description of the SEE Program, its accomplishments, and future activities is provided.

  3. The Space Debris Environment for the ISS Orbit

    NASA Technical Reports Server (NTRS)

    Theall, Jeff; Liou, Jer-Chyi; Matney, Mark; Kessler, Don

    2001-01-01

    With thirty-five planned missions over the next five years, the International Space Station (ISS) will be the focus for manned space activity. At least 6 different vehicles will transport crew and supplies to and from the nominally 400 km, 51.6 degree orbit. When completed, the ISS will be the largest space structure ever assembled and hence the largest target for space debris. Recent work at the Johnson Space Center has focused on updating the existing space debris models. The Orbital Debris Engineering Model, has been restructured to take advantage of state of the art desktop computing capability and revised with recent measurements from Haystack and Goldstone radars, additional analysis of LDEF and STS impacts, and the most recent SSN catalog. The new model also contains the capability to extrapolate the current environment in time to the year 2030. A revised meteoroid model based on the work of Divine has also been developed, and is called the JSC Meteoroid Model. The new model defines flux on the target per unit angle per unit speed, and for Earth orbit, includes the meteor showers. This paper quantifies the space debris environment for the ISS orbit from natural and anthropogenic sources. Particle flux and velocity distributions as functions of size and angle are be given for particles 10 microns and larger for altitudes from 350 to 450 km. The environment is projected forward in time until 2030.

  4. Electrodynamic Dust Shields on the International Space Station: Exposure to the Space Environment

    NASA Technical Reports Server (NTRS)

    Calle, C. I.; Hogue, M. D.; Johansen, M. R.; Yim, H.; Delaune, P. B.; Clements, J. S.

    2012-01-01

    Electrodynamic Dust Shields (EDS) have been in development at NASA as a dust mitigation method for lunar and Martian missions. An active dust mitigation strategy. such as that provided by the EDS, that can remove dust from surfaces, is of crucial importance to the planetary exploration program. We report on the development of a night experiment to fully ex pose four EDS panels to the space environment. This flight experiment is part of the Materials International Space Station experiment X(MISSE-X). an external platform on the International Space Station that will expose materials to the space environment.

  5. Center for Space Power and Advanced Electronics, Auburn University

    NASA Technical Reports Server (NTRS)

    Deis, Dan W.; Hopkins, Richard H.

    1991-01-01

    The union of Auburn University's Center for Space Power and Advanced Electronics and the Westinghouse Science and Technology Center to form a Center for the Commercial Development of Space (CCDS) is discussed. An area of focus for the CCDS will be the development of silicon carbide electronics technology, in terms of semiconductors and crystal growth. The discussion is presented in viewgraph form.

  6. Qualification of quantum cascade lasers for space environments

    SciTech Connect

    Myers, Tanya L.; Cannon, Bret D.; Brauer, Carolyn S.; Crowther, Blake; Hansen, Stewart

    2014-06-11

    Laser-based instruments are enabling a new generation of scientific instruments for space environments such as those used in the exploration of Mars. The lasers must be robust and able to withstand the harsh environment of space, including radiation exposure. Quantum cascade lasers (QCLs), which are semiconductor lasers that emit in the infrared spectral region, offer the potential for the development of novel laser-based instruments for space applications. The performance of QCLs after radiation exposure, however, has not been reported. We report on work to quantify the performance of QCLs after exposure to two different radiation sources, 64 MeV protons and Cobalt-60 gamma rays, at radiation levels likely to be encountered during a typical space flight mission. No significant degradation in threshold current or slope efficiency is observed for any of the seven Fabry-Perot QCLs that are tested.

  7. Degradation of Spacecraft Materials in the Space Environment

    NASA Technical Reports Server (NTRS)

    Miller, Sharon K. R.; Banks, Bruce A.

    2010-01-01

    When we think of space, we typically think of a vacuum containing very little matter that lies between the Earth and other planetary and stellar bodies. However, the space above Earth's breathable atmosphere and beyond contains many things that make designing durable spacecraft a challenge. Depending on where the spacecraft is flyng, it may encounter atomic oxygen, ultraviolet and other forms of radiation, charged particles, micrormeteoroids and debris, and temperature extremes. These environments on their own and in combination can cause degradation and failure of polymers, composites, paints and other materials used on the exterior of spacecraft for thermal control, structure, and power generation. This article briefly discusses and gives examples of some of the degradation experienced on spacecraft and night experiments as a result of the space environment and the use of ground and space data to predict durability.

  8. Large electron screening effect in different environments

    SciTech Connect

    Cvetinović, Aleksandra Lipoglavšek, Matej; Markelj, Sabina; Vesić, Jelena

    2015-10-15

    Electron screening effect was studied in the {sup 1}H({sup 7}Li,α){sup 4}He, {sup 1}H({sup 11}B,α){sup 4}He and {sup 1}H({sup 19}F,αγ){sup 16}O reactions in inverse kinematics on different hydrogen implanted targets. Results show large electron screening potentials strongly dependent on the proton number Z of the projectile.

  9. Optical modeling in Testbed Environment for Space Situational Awareness (TESSA).

    PubMed

    Nikolaev, Sergei

    2011-08-01

    We describe optical systems modeling in the Testbed Environment for Space Situational Awareness (TESSA) simulator. We begin by presenting a brief outline of the overall TESSA architecture and focus on components for modeling optical sensors. Both image generation and image processing stages are described in detail, highlighting the differences in modeling ground- and space-based sensors. We conclude by outlining the applicability domains for the TESSA simulator, including potential real-life scenarios. PMID:21833092

  10. Space Environment Studies from CRRES, APEX, and DMSP Satellite Data

    NASA Astrophysics Data System (ADS)

    Delorey, Dennis E.; Madden, Daniel; Holeman, Ernest; Parsons, Carolyn M.; Pruneau, Paul N.; Palys, John; Martin, Kevin R.

    1996-01-01

    The Institute for Scientific Research (ISR) of Boston College was contracted by the Space Physics Division (GPS) of the Phillips Laboratory (PL) Geophysics Directorate to perform research in the area of Space Particle Modeling and Effects. A number of computer models and simulations were developed by use of the data from various spacecraft including the Combined Release and Radiation Effects Satellite (CRRES), Defense Meteorological Satellite Program (DMSP), and Advanced Photovoltaic and Electronics Experiment (APEX).

  11. Advanced Engineering Environments for Space Transportation System Development

    NASA Technical Reports Server (NTRS)

    Thomas, L. Dale; Smith, Charles A.; Beveridge, James

    2000-01-01

    There are significant challenges facing today's launch vehicle industry. Global competition, more complex products, geographically-distributed design teams, demands for lower cost, higher reliability and safer vehicles, and the need to incorporate the latest technologies quicker, all face the developer of a space transportation system. Within NASA, multiple technology development and demonstration projects are underway toward the objectives of safe, reliable, and affordable access to space. New information technologies offer promising opportunities to develop advanced engineering environments to meet these challenges. Significant advances in the state-of-the-art of aerospace engineering practice are envisioned in the areas of engineering design and analytical tools, cost and risk tools, collaborative engineering, and high-fidelity simulations early in the development cycle. At the Marshall Space Flight Center, work has begun on development of an advanced engineering environment specifically to support the design, modeling, and analysis of space transportation systems. This paper will give an overview of the challenges of developing space transportation systems in today's environment and subsequently discuss the advanced engineering environment and its anticipated benefits.

  12. A study of dynamical behavior of space environment

    NASA Technical Reports Server (NTRS)

    Wu, S. T.

    1974-01-01

    Studies have covered a wide range of problems in the space environment, such as the problems of the dynamical behavior of the thermosphere, hydromagnetic wave propagation in the ionosphere, and interplanetary space environment. The theories used to analyze these problems range from a continuum theory of magnetohydrodynamics to the kinetic theory of free molecular flow. This is because the problems encountered covered the entire range of the Knudsen number (i.e., the ratio of mean free path to the characteristic length). Significant results are summarized.

  13. Protection of celestial environments and the law of outer space

    NASA Astrophysics Data System (ADS)

    Tennen, Leslie; Race, Margaret

    The law of outer space expressly addresses the matter of preservation and protection of natural celestial environments from harmful contamination and disruption by mankind in the explo-ration and use of outer space, including the moon and other celestial bodies. The Outer Space Treaty, however, does not prohibit all human impact to an extraterrestrial environment, but rather permits a wide range of activities that could have significant environmental ramifications. This legal regime may be in conflict with the interests of preserving celestial environments for scientific research, especially when considered in relation to activities conducted for commercial purposes. Nevertheless, the Moon Agreement provides a mechanism by which special protective measures can be implemented to protect particular areas of the moon and other celestial bodies for scientific investigation. This paper examines the current status of the law of outer space vis-a-vis the protection and preservation of natural celestial environments. Particular emphasis is placed on the policies on which the legal obligations are based, together with consideration of the non-appropriation principle, and the commercial use of lunar and other celestial resources and areas. In addition, the concepts of international scientific preserves, special regions, keep out zones, and planetary parks are compared and evaluated as potential means to limit the disturbance to celestial environments caused by the activities of mankind.

  14. Special requirements for electronics to be used in robots in space

    SciTech Connect

    Sias, F.R.

    1994-12-31

    Robots have been developed for use in hazardous environments and space certainly falls in the category of a hazardous environment. Microcomputers and electronics used to control robotic systems to be employed in space face greater threats than earth-bound robots used around radioactive materials. It is well known that nuclear radiation damages semiconductor devices by causing charges to build up in silicon dioxide insulating layers when the devices are exposed to ionizing radiation. Electronics suffer from doses of radiation when used around radioactive materials; however, additional sources of damage are present when the robots are used in space. This paper is a review of the problems that must be considered when developing electronics for robots to be used in space and some of the available solutions.

  15. International Space Station Increment-2 Microgravity Environment Summary Report

    NASA Technical Reports Server (NTRS)

    Jules, Kenol; Hrovat, Kenneth; Kelly, Eric; McPherson, Kevin; Reckart, Timothy

    2002-01-01

    This summary report presents the results of some of the processed acceleration data, collected aboard the International Space Station during the period of May to August 2001, the Increment-2 phase of the station. Two accelerometer systems were used to measure the acceleration levels during activities that took place during the Increment-2 segment. However, not all of the activities were analyzed for this report due to time constraints, lack of precise information regarding some payload operations and other station activities. The National Aeronautics and Space Administration sponsors the Microgravity Acceleration Measurement System and the Space Acceleration Microgravity System to support microgravity science experiments, which require microgravity acceleration measurements. On April 19, 2001, both the Microgravity Acceleration Measurement System and the Space Acceleration Measurement System units were launched on STS-100 from the Kennedy Space Center for installation on the International Space Station. The Microgravity Acceleration Measurement System unit was flown to the station in support of science experiments requiring quasi-steady acceleration measurements, while the Space Acceleration Measurement System unit was flown to support experiments requiring vibratory acceleration measurement. Both acceleration systems are also used in support of vehicle microgravity requirements verification. The International Space Station Increment-2 reduced gravity environment analysis presented in this report uses acceleration data collected by both sets of accelerometer systems: 1) The Microgravity Acceleration Measurement System, which consists of two sensors: the Orbital Acceleration Research Experiment Sensor Subsystem, a low frequency range sensor (up to 1 Hz), is used to characterize the quasi-steady environment for payloads and the vehicle, and the High Resolution Accelerometer Package, which is used to characterize the vibratory environment up to 100 Hz. 2) The Space

  16. International Space Station Increment-3 Microgravity Environment Summary Report

    NASA Technical Reports Server (NTRS)

    Jules, Kenol; Hrovat, Kenneth; Kelly, Eric; McPherson, Kevin; Reckart, Timothy; Grodsinksy, Carlos

    2002-01-01

    This summary report presents the results of some of the processed acceleration data measured aboard the International Space Station during the period of August to December 2001. Two accelerometer systems were used to measure the acceleration levels for the activities that took place during Increment-3. However, not all of the activities were analyzed for this report due to time constraint and lack of precise timeline information regarding some payload operations and station activities. The National Aeronautics and Space Administration sponsors the Microgravity Acceleration Measurement System and the Space Acceleration Microgravity System to support microgravity science experiments which require microgravity acceleration measurements. On April 19, 2001, both the Microgravity Acceleration Measurement System and the Space Acceleration Measurement System units were launched on STS-100 from the Kennedy Space Center for installation on the International Space Station. The Microgravity Acceleration Measurement System unit was flown to the station in support of science experiments requiring quasi-steady acceleration measurements, while the Space Acceleration Measurement System unit was flown to support experiments requiring vibratory acceleration measurement. Both acceleration systems are also used in support of the vehicle microgravity requirements verification. The International Space Station Increment-3 reduced gravity environment analysis presented in this report uses acceleration data collected by both sets of accelerometer systems: (1) The Microgravity Acceleration Measurement System, which consists of two sensors: the Orbital Acceleration Research Experiment Sensor Subsystem, a low frequency range sensor (up to 1 Hz), is used to characterize the quasi-steady environment for payloads and vehicle, and the High Resolution Accelerometer Package, which is used to characterize the vibratory environment up to 100 Hz. (2) The Space Acceleration Measurement System, which is

  17. Space industrialization. [space flight and environment for commercial/utilitarian purposes

    NASA Technical Reports Server (NTRS)

    Disher, J. H.

    1977-01-01

    Space industrialization is defined as the use of space flight and the space environment for commercial or utilitarian purposes in contrast to other uses such as gains in basic scientific knowledge, national defense, or exploration. Some unique attributes of space that make it amenable to industrial use include overview of the earth, the 'zero gravity' effect, potential for near perfect vacuum, unlimited reservoir for disposal of waste products, availability of essentially uninterrupted flow of solar energy, and the 'perpetual motion' characteristic of orbital mechanics. The role of human participation in assembling and maintaining the large sophisticated systems that will be required for future space industrialization needs is considered.

  18. Solar Cycle Variation and Application to the Space Radiation Environment

    NASA Technical Reports Server (NTRS)

    Wilson, John W.; Kim, Myung-Hee Y.; Shinn, Judy L.; Tai, Hsiang; Cucinotta, Francis A.; Badhwar, Gautam D.; Badavi, Francis F.; Atwell, William

    1999-01-01

    The interplanetary plasma and fields are affected by the degree of disturbance that is related to the number and types of sunspots in the solar surface. Sunspot observations were improved with the introduction of the telescope in the seventeenth century, allowing observations which cover many centuries. A single quantity (sunspot number) was defined by Wolf in 1848 that is now known to be well correlated with many space observable quantities and is used herein to represent variations caused in the space radiation environment. The resultant environmental models are intended for future aircraft and space-travel-related exposure estimates.

  19. Space - A unique environment for process modeling R&D

    NASA Technical Reports Server (NTRS)

    Overfelt, Tony

    1991-01-01

    Process modeling, the application of advanced computational techniques to simulate real processes as they occur in regular use, e.g., welding, casting and semiconductor crystal growth, is discussed. Using the low-gravity environment of space will accelerate the technical validation of the procedures and enable extremely accurate determinations of the many necessary thermophysical properties. Attention is given to NASA's centers for the commercial development of space; joint ventures of universities, industries, and goverment agencies to study the unique attributes of space that offer potential for applied R&D and eventual commercial exploitation.

  20. Power Converters Secure Electronics in Harsh Environments

    NASA Technical Reports Server (NTRS)

    2013-01-01

    In order to harden power converters for the rigors of space, NASA awarded multiple SBIR contracts to Blacksburg, Virginia-based VPT Inc. The resulting hybrid DC-DC converters have proven valuable in aerospace applications, and as a result the company has generated millions in revenue from the product line and created four high-tech jobs to handle production.

  1. Reproduction in the space environment: Part I. Animal reproductive studies

    NASA Technical Reports Server (NTRS)

    Santy, P. A.; Jennings, R. T.; Craigie, D.

    1990-01-01

    Mankind's exploration and colonization of the frontier of space will ultimately depend on men's and women's ability to live, work, and reproduce in the space environment. This paper reviews animal studies, from microorganisms to mammals, done in space or under space-simulated conditions, which identify some of the key areas which might interfere with human reproductive physiology and/or embryonic development. Those space environmental factors which impacted almost all species included: microgravity, artificial gravity, radiation, and closed life support systems. These factors may act independently and in combination to produce their effects. To date, there have been no studies which have looked at the entire process of reproduction in any animal species. This type of investigation will be critical in understanding and preventing the problems which will affect human reproduction. Part II will discuss these problems directly as they relate to human physiology.

  2. NASA's Controlled Environment Agriculture Testing for Space Habitats

    NASA Technical Reports Server (NTRS)

    Wheeler, Raymond M.

    2014-01-01

    NASA and other space agencies have an interest in using plants for human life support in space. The plants could provide food and O2 for the humans, while removing CO2 and helping purify wastewater. Studies to date have shown that a wide range of crops can be grown in controlled environment conditions envisioned for space. Light is a critical factor both for crop productivity and system power costs, and recent improvements in LEDs make them a preferred lighting option for space. Because space systems would be tightly closed, issues such as ethylene build-up and management must be considered. Ultimately, the costs and reliability of biological life support options must be compared with more conventional life support approaches. Findings to date suggest that about 20-25 sq. meters of crops could supply the O2 for one human, while about 50 sq. meters would be required for food (dietary calories).

  3. The Revised Space Environment Models in CREME-MC: A Replacement for CREME96

    NASA Technical Reports Server (NTRS)

    Adams, James H., Jr.; Barghouty, Abdulnasser F.; Mendenhall, Marcus H.; Reed, Robert A.; Sierawski, Brian; Watts, John W.; Weller, Robert A.

    2010-01-01

    The CREME96 model has been available on the WWW for more than 10 years now. While principally for the estimation of radiation effects on spacecraft electronics, it contains space radiation environment models that have been used for instrument design calculations, estimation of instrumental background, estimation of radiation hazards and many other purposes. Because of the evolution of electronic part design we have found it necessary to revise CREME96, creating CREME-MC. As part of this revision, we are revising and extending the environmental models in CREME96. This talk will describe the revised radiation environment models that are being made available in CREME-MC

  4. The use of perfluoroether lubricants in unprotected space environments

    NASA Technical Reports Server (NTRS)

    Baxter, B. H.; Hall, B. P.

    1985-01-01

    A series of ball bearing tests in simulated space environment are described which determine durability of perfluoroether lubricants. The results of the examination of the test bearings for each stage are described and experimental techniques designed to overcome lubricant degradation are outlined.

  5. Radiation environment and hazards for a geosynchronous space station

    NASA Technical Reports Server (NTRS)

    Wright, J. J.; Fishman, G. J.

    1976-01-01

    An evaluation was made of the potential radiation hazards to the crew and equipment of a geosynchronous space station. Tissue dose rates for electron, bremsstrahlung, galactic cosmic rays, and solar proton events are included for parking longitudes of 110 and 290 degrees at orbit inclinations of 0, 30, and 45 degrees.

  6. An Environment Monitoring Package for the International Space Station

    NASA Technical Reports Server (NTRS)

    Carruth, M. Ralph; Clifton, Kenneth S.

    1998-01-01

    The first elements of the International Space Station (ISS) will soon be launched into space and over the next few years ISS will be assembled on orbit into its final configuration. Experiments will be performed on a continuous basis both inside and outside the station. External experiments will be mounted on attached payload locations specifically designed to accommodate experiments, provide data and supply power from ISS. From the beginning of the space station program it has been recognized that experiments will require knowledge of the external local environment which can affect the science being performed and may impact lifetime and operations of the experiment hardware. Recently an effort was initiated to design and develop an Environment Monitoring Package (EMP). This paper describes the derivation of the requirements for the EMP package, the type of measurements that the EMP will make and types of instruments which will be employed to make these measurements.

  7. Combustion modeling for experimentation in a space environment

    NASA Technical Reports Server (NTRS)

    Berlad, A. L.

    1974-01-01

    The merits of combustion experimentation in a space environment are assessed, and the impact of such experimentation on current theoretical models is considered. It is noted that combustion theory and experimentation for less than normal gravitational conditions are incomplete, inadequate, or nonexistent. Extensive and systematic experimentation in a space environment is viewed as essential for more adequate and complete theoretical models of such processes as premixed flame propagation and extinction limits, premixed flame propagation in droplet and particle clouds, ignition and autoignition in premixed combustible media, and gas jet combustion of unpremixed reactants. Current theories and models in these areas are described, and some combustion studies that can be undertaken in the Space Shuttle Program are proposed, including crossed molecular beam, turbulence, and upper pressure limit (of gases) studies.

  8. EnviroNET: An interactive space-environment information resource

    NASA Technical Reports Server (NTRS)

    Vampola, Alfred L.; Hall, William N.; Lauriente, Michael

    1988-01-01

    EnviroNET is an interactive menu-driven system set up as an information resource for experimenters, program managers, and design and test engineers involved in space missions. Its basic use is as a fundamental single source of data for the environment encountered by Shuttle and Space Station payloads, but it also has wider applicability in that it includes information on environments encountered by other satellites in both low altitude and high altitude (including geosynchronous) orbits. It incorporates both a text-retrieval mode and an interactive modeling code mode. The system is maintained on the ENVET MicroVAX computer at NASA/Goddard Space Flight Center. Its services are available at no cost to any user who has access to a terminal and modem. It is a tail-node on SPAN, and so it is accessible either directly or through BITNET, ARPANET, and GTE/TELENET via NPSS.

  9. EnviroNET - An interactive space-environment information resource

    NASA Technical Reports Server (NTRS)

    Vampola, A. L.; Hall, William N.; Lauriente, Michael

    1989-01-01

    EnviroNET is an interactive menu-driven system set up as an information resource for experimenters, program managers, and design and test engineers involved in space missions. Its basic use is as a fundamental single source of data for the environment encountered by Shuttle and Space Station payloads, but is also has wider applicability in that it includes information on environments encountered by other satellites in both low altitude and high altitude (including geosynchronous) orbits. It incorporates both a text-retrieval mode and an interactive modeling code mode. The system is maintained on the ENVET MicroVAX computer at NASA/Goddard Space Flight Center. Its services are available at no cost to any user who has access to a terminal and modem. It is a tail-node on SPAN, and so it is accessible either directly or through BITNET, ARPANET, and GTE/TELENET via NPSS.

  10. The Next Generation of Space Cells for Diverse Environments

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.; Bailey, Sheila; Raffaelle, Ryne; Lyons, Valerie J. (Technical Monitor)

    2002-01-01

    Future science, military and commercial space missions are incredibly diverse. Military and commercial missions range from large arrays of hundreds of kilowatt to small arrays of ten watts in various Earth orbits. While science missions also have small to very large power needs there are additional unique requirements to provide power for near-sun missions and planetary exploration including orbiters, landers and rovers both to the inner planets and the outer planets with a major emphasis in the near term on Mars. These mission requirements demand cells for low intensity, low temperature applications, high intensity, high temperature applications, dusty environments and often high radiation environments. This paper discusses mission requirements, the current state of the art of space solar cells, and a variety of both evolving thin-film cells as well as new technologies that may impact the future choice of space solar cells for a specific mission application.

  11. Human response to vibroacoustic environments of space vehicles

    NASA Astrophysics Data System (ADS)

    Willshire, K. F.

    1984-10-01

    To insure efficient utilization of the system, space station design and operations will require special habitability considerations for the occupants and crew because of the relatively long duration missions. Of particular concern is the environment in which the personnel will live and work, and how it affects both the performance and comfort of the occupants. Current criteria do not consider possible effects of reduced gravity, long duration, and confinement. Preliminary to developing space station vibroacoustic habitability criteria, the adequacy of criteria for other space vehicles has been reviewed. In this paper, responses to the noise and vibration environments of both Skylab and Shuttle are discussed. Some astronauts have reported sleep interference, communication interference, distraction, and general annoyance as noise related complaints. In addition, information from the Russian Salyut missions, as well as similar based situtations (e.g., submarines), is reviewed.

  12. Human response to vibroacoustic environments of space vehicles

    NASA Technical Reports Server (NTRS)

    Willshire, K. F.

    1984-01-01

    To insure efficient utilization of the system, space station design and operations will require special habitability considerations for the occupants and crew because of the relatively long duration missions. Of particular concern is the environment in which the personnel will live and work, and how it affects both the performance and comfort of the occupants. Current criteria do not consider possible effects of reduced gravity, long duration, and confinement. Preliminary to developing space station vibroacoustic habitability criteria, the adequacy of criteria for other space vehicles has been reviewed. In this paper, responses to the noise and vibration environments of both Skylab and Shuttle are discussed. Some astronauts have reported sleep interference, communication interference, distraction, and general annoyance as noise related complaints. In addition, information from the Russian Salyut missions, as well as similar based situtations (e.g., submarines), is reviewed.

  13. Space applications of superconductivity - Digital electronics

    NASA Technical Reports Server (NTRS)

    Harris, R. E.

    1980-01-01

    Superconducting electronics offers a variety of remarkable properties including high speed and low dissipation. The paper discusses fundamental considerations which appear to suggest that superconducting (cryogenic) technology will offer significant advantages for future digital devices. It shows how the active element in superconducting electronics, the Josephson junction, works and discusses the technology for fabricating the devices. The characteristics of published circuits are briefly reviewed, and the capabilities of future superconducting computers and instruments are projected.

  14. A model environment for outer zone electrons

    NASA Technical Reports Server (NTRS)

    Singley, G. W.; Vette, J. I.

    1972-01-01

    A brief morphology of outer zone electrons is given to illustrate the nature of the phenomena that we are attempting to model. This is followed by a discussion of the data processing that was done with the various data received from the experimenters before incorporating it into the data base from which this model was ultimately derived. The details of the derivation are given, and several comparisons of the final model with the various experimental measurements are presented.

  15. Plant growth chamber based on space proven controlled environment technology

    SciTech Connect

    Ignatius, R.W.; Ignatius, M.H.; Imberti, H.J.

    1997-01-01

    Quantum Devices, Inc., in conjunction with Percival Scientific, Inc., and the Wisconsin Center for Space Automation and Robotics (WCSAR) have developed a controlled environment plant growth chamber for terrestrial agricultural and scientific applications. This chamber incorporates controlled environment technology used in the WCSAR ASTROCULTURE{trademark} flight unit for conducting plant research on the Space Shuttle. The new chamber, termed CERES 2010, features air humidity, temperature, and carbon dioxide control, an atmospheric contaminant removal unit, an LED lighting system, and a water and nutrient delivery system. The advanced environment control technology used in this chamber will increase the reliability and repeatability of environmental physiology data derived from plant experiments conducted in this chamber. {copyright} {ital 1997 American Institute of Physics.}

  16. Development, validation and application of numerical space environment models

    NASA Astrophysics Data System (ADS)

    Honkonen, Ilja

    2013-10-01

    Currently the majority of space-based assets are located inside the Earth's magnetosphere where they must endure the effects of the near-Earth space environment, i.e. space weather, which is driven by the supersonic flow of plasma from the Sun. Space weather refers to the day-to-day changes in the temperature, magnetic field and other parameters of the near-Earth space, similarly to ordinary weather which refers to changes in the atmosphere above ground level. Space weather can also cause adverse effects on the ground, for example, by inducing large direct currents in power transmission systems. The performance of computers has been growing exponentially for many decades and as a result the importance of numerical modeling in science has also increased rapidly. Numerical modeling is especially important in space plasma physics because there are no in-situ observations of space plasmas outside of the heliosphere and it is not feasible to study all aspects of space plasmas in a terrestrial laboratory. With the increasing number of computational cores in supercomputers, the parallel performance of numerical models on distributed memory hardware is also becoming crucial. This thesis consists of an introduction, four peer reviewed articles and describes the process of developing numerical space environment/weather models and the use of such models to study the near-Earth space. A complete model development chain is presented starting from initial planning and design to distributed memory parallelization and optimization, and finally testing, verification and validation of numerical models. A grid library that provides good parallel scalability on distributed memory hardware and several novel features, the distributed cartesian cell-refinable grid (DCCRG), is designed and developed. DCCRG is presently used in two numerical space weather models being developed at the Finnish Meteorological Institute. The first global magnetospheric test particle simulation based on the

  17. Developments in Radiation-Hardened Electronics Applicable to the Vision for Space Exploration

    NASA Technical Reports Server (NTRS)

    Keys, Andrew S.; Frazier, Donald O.; Patrick , Marshall C.; Watson, Michael D.; Johnson, Michael A.; Cressler, John D.; Kolawa, Elizabeth A.

    2007-01-01

    The Radiation Hardened Electronics for Space Exploration (RHESE) project develops the advanced technologies required to produce radiation hardened electronics, processors, and devices in support of the anticipated requirements of NASA's Constellation program. Methods of protecting and hardening electronics against the encountered space environment are discussed. Critical stages of a spaceflight mission that are vulnerable to radiation-induced interruptions or failures are identified. Solutions to mitigating the risk of radiation events are proposed through the infusion of RHESE technology products and deliverables into the Constellation program's spacecraft designs.

  18. Logic Design Pathology and Space Flight Electronics

    NASA Technical Reports Server (NTRS)

    Katz, Richard B.; Barto, Rod L.; Erickson, Ken

    1999-01-01

    This paper presents a look at logic design from early in the US Space Program and examines faults in recent logic designs. Most examples are based on flight hardware failures and analysis of new tools and techniques. The paper is presented in viewgraph form.

  19. Space Weather Monitoring for ISS Space Environments Engineering and Crew Auroral Observations

    NASA Astrophysics Data System (ADS)

    Minow, J. I.; Pettit, D. R.; Hartman, W. A.

    2012-12-01

    The International Space Station (ISS) space environments community utilizes near real time space weather data in support of a variety of ISS engineering and operations activities. The team has operated the Floating Potential Measurement Unit (FPMU) suite of plasma instruments (two Langmuir probes, a floating potential probe, and a plasma impedance probe) on ISS from 2006 to the present time to obtain in-situ measurements of plasma density and temperature along the ISS orbit and variations in ISS frame potential due to the combined effects of electrostatic current collection processes from the plasma environment and inductive (vxB) effects due to the motion of the vehicle across the Earth's magnetic field. An ongoing effort to use FPMU for measuring the ionospheric response to geomagnetic storms at ISS altitudes and document ISS frame charging as the vehicle passes through regions of precipitating auroral electrons is challenged by restrictions on the available FPMU operation time. The instruments can only be operated during campaign periods limited to about a third of a year in accumulated operation time and FPMU data is down linked through the ISS Ku band telemetry system, a shared resource. As a result, FPMU campaign periods of a few days to weeks have typically been scheduled for periods of a week or two in advance. Capturing geomagnetic storm data under these conditions depended on the fortuitous event of a storm starting during a previously planned FPMU campaign period, an unlikely event at a time when Solar Cycle 24 was ending and a protracted solar minimum gave little in the way of geoeffective solar disturbances. However, with the start of Solar Cycle 24 the number of solar disturbances and associated geomagnetic storms started to increase and we modified our strategy to improve the chances of capturing geomagnetic storm data. We now monitor near real time space weather data from NASA, NOAA, and ESA sources to determine solar wind disturbance arrival times

  20. The microgravity environment for experiments on the International Space Station

    NASA Technical Reports Server (NTRS)

    Nelson, Emily S.; Jules, Kenol

    2004-01-01

    Experiments are sent to space laboratories in order to take advantage of the low-gravity environment. However, it is crucial to appreciate the distinction between the real microgravity environment and "weightlessness" or "simulated microgravity". The microgravity in space laboratories may be of much smaller magnitude than the gravitational acceleration on earth. However, it is not zero, nor even one microg (defined as 1e-6 earth gravity). Moreover, the orientation is not uniaxial, as on earth. The net acceleration that acts on a space experiment arises from, e.g., orbital mechanics, atmospheric drag, and thruster firings, and it can act on the experiments in gravity-like ways. In essence, a well-defined, stable 1 g acceleration on the earth's surface is substituted for a complex array of dynamically changing accelerations with ever-changing frequency content, magnitude and direction. This paper will show measured accelerations on the Shuttle from launch to orbit, as well as the latest measurements on the International Space Station (ISS). The ISS data presented here represent over 34,790 hours of data obtained from June 2002 to April 2003 during Increments 5 and 6 of the ISS construction cycle. The quasisteady acceleration level on the ISS has been measured to be on the order of a few microg during time allotted to microgravity mode. The vibratory acceleration environment spans a rich spectrum from 0.01-300 Hz.

  1. Lead-Free Electronics: Impact for Space Electronics

    NASA Technical Reports Server (NTRS)

    Sampson, Michael J.

    2010-01-01

    Pb is used as a constituent in solder alloys used to connect and attach electronic parts to printed wiring boards (PWBs). Similar Pbbearing alloys are electroplated or hot dipped onto the terminations of electronic parts to protect the terminations and make them solderable. Changing to Pb-free solders and termination finishes has introduced significant technical challenges into the supply chain. Tin/lead (Sn/Pb) alloys have been the solders of choice for electronics for more than 50 years. Pb-free solder alloys are available but there is not a plug-in replacement for 60/40 or 63/37 (Sn/Pb) alloys, which have been the industry workhorses.

  2. High temperature electronics applications in space exploration

    NASA Technical Reports Server (NTRS)

    Jurgens, R. F.

    1981-01-01

    The extension of the range of operating temperatures of electronic components and systems for planetary exploration is examined. In particular, missions which utilize balloon-borne instruments to study the Venusian and Jovian atmospheres are discussed. Semiconductor development and devices including power sources, ultrastable oscillators, transmitters, antennas, electromechanical devices, and deployment systems are addressed.

  3. Extreme Space Weather Events and Charging Hazard Assessments in Lunar Environments

    NASA Technical Reports Server (NTRS)

    Minow, Joseph I.; Parker, Linda N.; Blackwell, William C., Jr.

    2008-01-01

    The sunlit lunar surface charges to positive potentials with mean values of a few tens of volts where photoelectron currents dominate the charging process. In contrast, surfaces in darkness may charge to negative potentials on the order of a few hundred volts when the charging process is dominated by hot electron populations in the absence of solar photons. Recently, observations of electron beams measured by instruments on spacecraft in low lunar orbit have been interpreted as evidence for extreme lunar surface potentials exceeding a few kilovolts suggesting that lunar orbital and surface plasma environments may contain charging risks similar to geostationary orbit during extreme space weather conditions. Space system design for successful operation in a wide range of lunar environments will therefore require evaluation of charging hazards during extreme space weather conditions. We present results from a study of space weather environments conducted to obtained credible extreme charging environments for use in charging hazard assessments for lunar missions including extreme conditions encountered when the Moon is in the solar wind, the magnetosheath, and the Earth's magnetotail.

  4. Initial Assesment of Space Launch System Transonic Unsteady Pressure Environment

    NASA Technical Reports Server (NTRS)

    Sekula, Martin K.; Piatak, David J.; Rausch, Russ D.; Florance, James R.; Ramey, James M.

    2015-01-01

    A series of wind tunnel tests were conducted at the NASA Langley Research Center Transonic Dynamics Tunnel to assess the transonic buffet environment for the Space Launch System (SLS) launch vehicle. An initial test, conducted in 2012, indicated an elevated buffet environment prompting a second test to provide further insight into the buffet phenomena and assess potential solutions to reduce the response levels of these environments. During the course of the test program, eight variants of the SLS-10000 configuration were examined. The effect of these configuration variants on the coefficient of the root-mean-square fluctuation of pressure about the mean as a function of test condition indicates that the maximum fluctuating pressure levels are extremely sensitive to the geometry of the forward attachment of the solid rocket boosters (SRBs) to the SLS Core. The addition of flow fences or changes to the SRB nose cone geometry can alleviate the unsteady pressure environment.

  5. Assessing Built Environment Walkability using Activity-Space Summary Measures

    PubMed Central

    Tribby, Calvin P.; Miller, Harvey J.; Brown, Barbara B.; Werner, Carol M.; Smith, Ken R.

    2015-01-01

    There is increasing emphasis on active transportation, such as walking, in transportation planning as a sustainable form of mobility and in public health as a means of achieving recommended physical activity and better health outcomes. A research focus is the influence of the built environment on walking, with the ultimate goal of identifying environmental modifications that invite more walking. However, assessments of the built environment for walkability are typically at a spatially disaggregate level (such as street blocks) or at a spatially aggregate level (such as census block groups). A key issue is determining the spatial units for walkability measures so that they reflect potential walking behavior. This paper develops methods for assessing walkability within individual activity spaces: the geographic region accessible to an individual during a given walking trip. We first estimate street network-based activity spaces using the shortest path between known trip starting/ending points and a travel time budget that reflects potential alternative paths. Based on objective walkability measures of the street blocks, we use three summary measures for walkability within activity spaces: i) the average walkability score across block segments (representing the general level of walkability in the activity space); ii) the standard deviation (representing the walkability variation), and; iii) the network autocorrelation (representing the spatial coherence of the walkability pattern). We assess the method using data from an empirical study of built environment walkability and walking behavior in Salt Lake City, Utah, USA. We visualize and map these activity space summary measures to compare walkability among individuals’ trips within their neighborhoods. We also compare summary measures for activity spaces versus census block groups, with the result that they agree less than half of the time. PMID:27213027

  6. Development of fire resistant electronic configurations for use in oxygen enriched environments

    NASA Technical Reports Server (NTRS)

    Smith, F. J.

    1975-01-01

    Design concepts for electronic black boxes and modules were tested in oxygen enriched atmospheres, and it was found that various types of sealed configurations would generally eliminate any flammability hazard. The type of configuration and its construction was found to be of more importance in the elimination of flammability hazards in electronic configurations than the types of materials utilized in them. The design concepts developed for fire hazard free electronic configurations for use in manned space programs are applicable for the design of electronic hardware for any use or environment.

  7. Studies of space-charge effects in ultrashort electron bunches

    SciTech Connect

    Fubiani, Gwenael; Leemans, Wim; Esarey, Eric

    2000-06-01

    Laser-driven plasma-based accelerators are capable of producing ultrashort electron bunches in which the longitudinal size is much smaller than the transverse size. We present theoretical studies of the transport of such electron bunches in vacuum. Space charge forces acting on the bunch are calculated using an ellipsoidal bunch shape model. The effects of space charge forces and energy spread on longitudinal and transverse bunch properties are evaluated for various bunch lengths energies and amount of charge.

  8. Contamination of the space station environment by vented chemicals

    NASA Technical Reports Server (NTRS)

    Bernhardt, Paul A.

    1988-01-01

    Gaseous materials vented from materials and life science experiments on the Space Station may have noticeable effects on the optical or plasma environment. The magnitude of the effects depends on: (1) rarefied gas dynamics; (2) photochemical reactions; and (3) airglow excitation mechanisms. In general, the effects from atomic species can be mitigated, but the disturbances resulting from venting of molecules like SF6, CO2 and C2H2 can be significant. The interaction of molecules with ambient plasma at orbital velocities should be studied with laboratory or space experiments.

  9. Space Shuttle Orbiter logistics - Managing in a dynamic environment

    NASA Technical Reports Server (NTRS)

    Renfroe, Michael B.; Bradshaw, Kimberly

    1990-01-01

    The importance and methods of monitoring logistics vital signs, logistics data sources and acquisition, and converting data into useful management information are presented. With the launch and landing site for the Shuttle Orbiter project at the Kennedy Space Center now totally responsible for its own supportability posture, it is imperative that logistics resource requirements and management be continually monitored and reassessed. Detailed graphs and data concerning various aspects of logistics activities including objectives, inventory operating levels, customer environment, and data sources are provided. Finally, some lessons learned from the Shuttle Orbiter project and logistics options which should be considered by other space programs are discussed.

  10. Wheat production in the controlled environments of space.

    PubMed

    Bugbee, B; Salisbury, F B

    1985-01-01

    Space agricultural research at the Utah State University includes studies of wheat growth in a controlled environment life support system. Wheat was chosen as a candidate for research in bioregenerative systems because it can be processed into a variety of foods, it is an efficient producer, it is a major world food crop, much is known about wheat genetics and breeding, it grows well in continuous light, and converts energy into a high grain yield. Studies examine quantum yield and short-term photosynthesis, growth rates, yield and harvest index, plant density and light intensity, carbon dioxide concentrations, and breeding wheat for space agriculture. PMID:11540895

  11. Modelling the near-Earth space environment using LDEF data

    NASA Technical Reports Server (NTRS)

    Atkinson, Dale R.; Coombs, Cassandra R.; Crowell, Lawrence B.; Watts, Alan J.

    1992-01-01

    Near-Earth space is a dynamic environment, that is currently not well understood. In an effort to better characterize the near-Earth space environment, this study compares the results of actual impact crater measurement data and the Space Environment (SPENV) Program developed in-house at POD, to theoretical models established by Kessler (NASA TM-100471, 1987) and Cour-Palais (NASA SP-8013, 1969). With the continuing escalation of debris there will exist a definite hazard to unmanned satellites as well as manned operations. Since the smaller non-trackable debris has the highest impact rate, it is clearly necessary to establish the true debris environment for all particle sizes. Proper comprehension of the near-Earth space environment and its origin will permit improvement in spacecraft design and mission planning, thereby reducing potential disasters and extreme costs. Results of this study directly relate to the survivability of future spacecraft and satellites that are to travel through and/or reside in low Earth orbit (LEO). More specifically, these data are being used to: (1) characterize the effects of the LEO micrometeoroid an debris environment on satellite designs and components; (2) update the current theoretical micrometeoroid and debris models for LEO; (3) help assess the survivability of spacecraft and satellites that must travel through or reside in LEO, and the probability of their collision with already resident debris; and (4) help define and evaluate future debris mitigation and disposal methods. Combined model predictions match relatively well with the LDEF data for impact craters larger than approximately 0.05 cm, diameter; however, for smaller impact craters, the combined predictions diverge and do not reflect the sporadic clouds identified by the Interplanetary Dust Experiment (IDE) aboard LDEF. The divergences cannot currently be explained by the authors or model developers. The mean flux of small craters (approximately 0.05 cm diameter) is

  12. Polymerisation processes in expoy resins under influence of free space environment

    NASA Astrophysics Data System (ADS)

    Kondyurin, A.; Lauke, B.; Kondyurina, I.

    A creation of large size constructions in space or on celestial bodies is possible by the way of chemical reactions of liquid viscous components under space environment conditions [1-2]. In particular, a new technology for large-size space module for electronic components, energy and materials production is developed on the basis of polymerisation technique. The factors of free space environment have a significant influence on the polymerisation processes. The polymerisation processes in active liquid components are sensitive to microgravitation, temperature variations (-150{ldots}+1500C), high vacuum (10-3{ldots}10-7 Pa), atomic oxygen flux (on LEO), UV and VUV irradiations, X-ray and γ -irradiations, high energy electron and ion fluxes. Experiments of polymerisation processes under simulated free space conditions were conducted. The influences of high vacuum, high energy ion beam and rf- and mw-plasma on polymerisation of epoxy resins were observed. The effects of low molecular components evaporations, free radical formations, additional chemical reactions and mixing processes during polymerisation were observed. Our results showed, that the space factors can initiate the polymerisation reaction in epoxy matrix of glass and carbon fibre composites. The result can be used for a technology for large size constructions on Earth orbit, in far space and on space bodies as for deployed antennas, solar sail stringers, solar shield stringers, frame for large-size space station, frame for Moon, Mars, asteroids bases, frame for space plant on Earth orbit and on other celestial bodies. The study was partially supported by Alexander von Humboldt Foundation (A. Kondyurin) and European Space Agency, ESTEC (contract 17083/03/NL/Sfe "Space Environmental Effects on the Polymerisation of Composite Structures"). 1. A.Kondyurin, B.Lauke, Polymerisation processes in simulated free space conditions, Proceedings of the 9th International Symposium on Materials in a Space Environment

  13. A Motor Drive Electronics Assembly for Mars Curiosity Rover: An Example of Assembly Qualification for Extreme Environments

    NASA Technical Reports Server (NTRS)

    Kolawa, Elizabeth; Chen, Yuan; Mojarradi, Mohammad M.; Weber, Carissa Tudryn; Hunter, Don J.

    2013-01-01

    This paper describes the technology development and infusion of a motor drive electronics assembly for Mars Curiosity Rover under space extreme environments. The technology evaluation and qualification as well as space qualification of the assembly are detailed and summarized. Because of the uncertainty of the technologies operating under the extreme space environments and that a high level reliability was required for this assembly application, both component and assembly board level qualifications were performed.

  14. Crew behavior and performance in space analog environments

    NASA Technical Reports Server (NTRS)

    Kanki, Barbara G.

    1992-01-01

    The objectives and the current status of the Crew Factors research program conducted at NASA-Ames Research Center are reviewed. The principal objectives of the program are to determine the effects of a broad class of input variables on crew performance and to provide guidance with respect to the design and management of crews assigned to future space missions. A wide range of research environments are utilized, including controlled experimental settings, high fidelity full mission simulator facilities, and fully operational field environments. Key group processes are identified, and preliminary data are presented on the effect of crew size, type, and structure on team performance.

  15. High temperature power electronics for space

    NASA Technical Reports Server (NTRS)

    Hammoud, Ahmad N.; Baumann, Eric D.; Myers, Ira T.; Overton, Eric

    1991-01-01

    A high temperature electronics program at NASA Lewis Research Center focuses on dielectric and insulating materials research, development and testing of high temperature power components, and integration of the developed components and devices into a demonstrable 200 C power system, such as inverter. An overview of the program and a description of the in-house high temperature facilities along with experimental data obtained on high temperature materials are presented.

  16. The Changing Information Needs of Users in Electronic Information Environments.

    ERIC Educational Resources Information Center

    Kebede, Gashaw

    2002-01-01

    Focuses on the information needs of users that are changing as a results of changes in the availability of information content in electronic form. Highlights the trend and nature of the physical form in which information content is currently being made available for users' access and use in electronic information environments. (Author/LRW)

  17. Environet: An interactive space-environment information resource

    NASA Astrophysics Data System (ADS)

    Vampola, A. L.; Hall, William N.; Lauriente, Michael

    1989-05-01

    EnviroNET is an interactive menu-driven system set up as an information resource for experimenters, program managers, and design and test engineers who are involved in space missions. Its basic use is as a fundamental single-source of data for the environment encountered by Shuttle and Space Station payloads, but is also has wider applicability in that it includes information on environments encountered by other satellites in both low altitude and high altitude (including geosynchronous) orbits. It incorporates both a text-retrieval mode and an interactive modeling code mode. The system is maintained on the ENVNET and MicroVAX computer at NASA/Goddard. It's services are available at no cost to any user who has access to a terminal and a dial-up port. It is a tail-node on SPAN and so it is accessible either directly or through BITNET, ARPANET, and GTE/TELENET via NPSS.

  18. Thermal preparation of foods in space-vehicle environments

    NASA Technical Reports Server (NTRS)

    Bannerot, R. B.; Cox, J. E.; Chen, C. K.; Heidelbaugh, N. D.

    1974-01-01

    Convection is the primary heat transfer mechanism for most foods heated in an earth-based environment. In contrast, in the low-gravity environment of space flight, the primary heat transfer mechanism is conduction (or radiation in the absence of a conducting medium). Conduction heating is significantly slower and less efficient than convection heating. This fact poses a problem for food heating during space flight. A numerical model has been developed to evaluate this problem. This model simulates the food-heating process for Skylab. The model includes the effect of a thermally controlled on/off heat flux. Parametric studies using this model establish how the required heating time is affected by: the thermal diffusivity of the nutrient materials, the power level of the heater, the initial food temperatures, and the food container dimensions.

  19. SEVO (Space Environment Viability of Organics) Preliminary Results from Orbit

    NASA Technical Reports Server (NTRS)

    Cook, A.; Ehrenfreund, P.; Mattioda, A.; Quinn, R.; Ricco, A. J.; Bramall, N.; Chittenden, J.; Bryson, K.; Minelli, G.

    2012-01-01

    SEVO (Space Environment Viability of Organics) is one of two astrobiology experiments onboard the NASA Organism/Organics Exposure to Orbital Stresses (O/OREOS) cubesat, launched in November 2010. The satellite is still operational with nominal performance and records data on a regular basis. In the SEVO experiment, four astrobiologically relevant organic thin films are exposed to radiation in low-earth orbit, including the unfiltered solar spectrum from approximately 120 - 2600 nm. The thin films are contained in each of four separate micro-environments: an atmosphere containing CO2, a low relative humidity (approximately 2%) atmosphere, an inert atmosphere representative of interstellar/interplanetary space, and a SiO2 mineral surface to measure the effects of surface catalysis. The UV/Vis spectrum of each sample is monitored in situ, with a spectrometer onboard the satellite.

  20. Telehealth: important concepts for future nursing practice in space environments.

    PubMed

    Chonin, A

    1998-01-01

    The concept of telehealth has become a vital issue to healthcare providers in this day of instantaneous, varied, and technology-based communications. This article discusses the issues and implications of telehealth to nurses on Earth and in future space environments. Telehealth will be defined as currently implemented and the legal ramifications of practice across state lines, national borders, rural, and in remote and hazardous locations (space environments: orbital, Moon and Mars bases) will be delineated. The age of information is now here, and the age of communication is beginning. Telehealth is and will be an important means of providing communication links and healthcare to clients and providers alike. Healthcare professionals need to be aware of important concepts related to telehealth for their current and future practice. PMID:11871451

  1. Effect of science laboratory centrifuge of space station environment

    NASA Technical Reports Server (NTRS)

    Searby, Nancy

    1990-01-01

    It is argued that it is essential to have a centrifuge operating during manned space station operations. Background information and a rationale for the research centrifuge are given. It is argued that we must provide a controlled acceleration environment for comparison with microgravity studies. The lack of control groups in previous studies throws into question whether the obseved effects were the result of microgravity or not. The centrifuge could be used to provide a 1-g environment to supply specimens free of launch effects for long-term studies. With the centrifuge, the specimens could be immediately transferred to microgravity without undergoing gradual acclimation. Also, the effects of artificial gravity on humans could be investigated. It is also argued that the presence of the centrifuge on the space station will not cause undo vibrations or other disturbing effects.

  2. Current Trends on the Applicability of Ground Aerospace Materials Test Data to Space System Environments

    NASA Technical Reports Server (NTRS)

    Hirsch, David B.

    2010-01-01

    This slide presentation discusses the application of testing aerospace materials to the environment of space for flammability. Test environments include use of drop towers, and the parabolic flight to simulate the low gravity environment of space.

  3. Practical application of HgI2 detectors to a space-flight scanning electron microscope

    NASA Technical Reports Server (NTRS)

    Bradley, J. G.; Conley, J. M.; Albee, A. L.; Iwanczyk, J. S.; Dabrowski, A. J.

    1989-01-01

    Mercuric iodide X-ray detectors have been undergoing tests in a prototype scanning electron microscope system being developed for unmanned space flight. The detector program addresses the issues of geometric configuration in the SEM, compact packaging that includes separate thermoelectric coolers for the detector and FET, X-ray transparent hermetic encapsulation and electrical contacts, and a clean vacuum environment.

  4. CESAR: Cryogenic Electronics for Space Applications

    NASA Astrophysics Data System (ADS)

    Revéret, V.; de la Broïse, X.; Fermon, C.; Pannetier-Lecoeur, M.; Pigot, C.; Rodriguez, L.; Sauvageot, J.-L.; Jin, Y.; Marnieros, S.; Bouchier, D.; Putzeys, J.; Long, Y.; Kiss, C.; Kiraly, S.; Barbera, M.; Lo Cicero, U.; Brown, P.; Carr, C.; Whiteside, B.

    2014-08-01

    Ultra-low temperature sensors provide unprecedented performances in X-ray and far infrared astronomy by taking advantage of physical properties of matter close to absolute zero. CESAR is an FP7 funded project started in December 2010, that gathers six European laboratories around the development of high performances cryogenic electronics. The goal of the project is to provide far-IR, X-ray and magnetic sensors with signal-processing capabilities at the heart of the detectors. We present the major steps that constitute the CESAR work, and the main results achieved so far.

  5. The Electron in Three-Dimensional Momentum Space

    NASA Astrophysics Data System (ADS)

    Mantovani, L.; Bacchetta, A.; Pasquini, B.

    2016-07-01

    We study the electron as a system composed of an electron and a photon and derive the leading-twist transverse-momentum-dependent distribution functions for both the electron and photon in the dressed electron, thereby offering a three-dimensional description of the dressed electron in momentum space. To obtain the distribution functions, we apply both the formalism of light-front wave function overlap representation and the diagrammatic approach; we discuss the comparison of our results between light-cone gauge and Feynman gauge, discussing the role of the Wilson lines to obtain gauge-independent results. We provide examples of plots of the computed distributions.

  6. Space Suit Environment Testing of the Orion Atmosphere Revitalization Technology

    NASA Technical Reports Server (NTRS)

    Button, Amy B.; Sweterlitsch, Jeffrey J.; Cox, Marlon R.

    2010-01-01

    An amine-based carbon dioxide (CO2) and water vapor sorbent in pressure-swing regenerable beds has been developed by Hamilton Sundstrand and baselined for the Orion Atmosphere Revitalization System (ARS). In three previous years at this conference, reports were presented on extensive Johnson Space Center (JSC) testing of this technology. That testing was performed in a sea-level pressure environment with both simulated and real human metabolic loads, and in both open and closed-loop configurations. The Orion ARS is designed to also support space-suited operations in a depressurized cabin, so the next step in developmental testing at JSC was to test the ARS technology in a typical closed space suit-loop environment with low-pressure oxygen inside the process loop and vacuum outside the loop. This was the first instance of low-pressure, high-oxygen, closed-loop testing of the Orion ARS technology, and it was conducted with simulated human metabolic loads in March 2009. The test investigated pressure drops and flow balancing through two different styles of prototype suit umbilical connectors. General swing-bed performance was tested with both umbilical configurations, as well as with a short jumper line installed in place of the umbilicals. Other interesting results include observations on the thermal effects of swing-bed operation in a vacuum environment and a recommendation of cycle time to maintain acceptable suit atmospheric CO2 and moisture levels.

  7. Degradation of optical components in a space environment

    NASA Technical Reports Server (NTRS)

    Dehainaut, Linda L.; Kenemuth, John; Tidler, Cynthia E.; Seegmiller, David W.

    1992-01-01

    The objective of the Phillips Laboratory (PL) Long Duration Exposure Facility (LDEF) experiment is to determine the adverse effects of the natural space environment on laser optical component and coating materials. The LDEF experiment provides a unique opportunity for the study of optical material response to an extended low earth orbit space exposure. The PL samples consist of 10 sets of the six materials each. The materials are uncoated fused silica, magnesium fluoride coated fused silica, uncoated molybdenum, molybdenum coated with chromium, silver and thorium fluoride, diamond turned copper, and diamond turned nickel plated copper. Performance degradation will be correlated to establish trends between sample location, duration of exposure, atomic oxygen exposure and other space environmental conditions. This paper discusses the results of the tests thus far performed on the LDEF samples and the plans for the future.

  8. Atmospheric environment for space shuttle (STS-38) launch

    NASA Technical Reports Server (NTRS)

    Jasper, G. L.; Batts, G. W.

    1991-01-01

    A summary of selected atmospheric conditions observed near space shuttle STS-38 launch time on November 15, 1990, at Kennedy Space Center is presented. STS-38 carried a Department of Defense payload and the flight azimuth in this report will be denoted by a reference flight azimuth, since the actual flight azimuth is not known. Values of ambient pressure, temperature, moisture, ground winds, visual observation (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere-measured vertical wind profiles is presented. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-38 vehicle ascent was constructed. The STS-38 ascent atmospheric data tape was constructed by Marshall Space Flight Center's Earth Science and Applications Division to provide an internally consistent data set for use in postflight performance assessments and represents the best estimate of the launch environment to the 400,000-ft altitude that was traversed by the STS-38 vehicle.

  9. Atmospheric environment for Space Shuttle Atlantis (STS-43) launch

    NASA Technical Reports Server (NTRS)

    Jasper, G. L.; Batts, G. W.

    1992-01-01

    A summary of selected atmospheric conditions observed near Space Shuttle Atlantis (STS-43) launch time on August 2, 1991, at Kennedy Space Center, Florida is presented. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere-measured vertical wind profiles is given. The final atmospheric profile, which consists of wind and thermodynamic parameters versus altitude, for STS-43 vehicle ascent was constructed. The STS-43 ascent atmospheric data profile was constructed by Marshall Space Flight Center's Earth Science and Applications Division to provide an internally consisted data set for use in postflight performance assessments and represents the best estimate of the launch environment to the 400,000-ft altitude that was traversed by the STS-43 vehicle.

  10. Atmospheric environment for space shuttle (STS-35) launch

    NASA Technical Reports Server (NTRS)

    Jasper, G. L.; Batts, G. W.

    1991-01-01

    A summary is given of selected atmospheric conditions observed near space shuttle STS-35 launch time on December 2, 1990, at Kennedy Space Center, Florida. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere-measured vertical wind profiles is given in this report. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-35 vehicle ascent has been constructed. The STS-35 ascent atmospheric data tape has been constructed by Marshall Space Flight Center's Earth Science and Applications Division to provide an internally consistent data set for use in postflight performance assessments and represents the best estimate of the launch environment to the 400,000-ft altitude that was traversed by the STS-35 vehicle.

  11. Atmospheric environment for space shuttle (STS-41) launch

    NASA Technical Reports Server (NTRS)

    Jasper, G. L.; Batts, G. W.

    1990-01-01

    A summary of selected atmospheric conditions observed near space shuttle STS-41 launch time on October 6, 1990, at Kennedy Space Center, Florida are presented. Values of ambient pressure, temperature, moisture, ground winds, visual observations (clouds), and winds aloft are included. The sequence of prelaunch Jimsphere-measured vertical wind profiles is given. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-41 vehicle ascent was constructed. The STS-41 ascent atmospheric data tape was constructed by Marshall Space Flight Center's Earth Science and Applications Division to provide an internally consistent data set for use in postflight performance assessments and represents the best estimate of the launch environment to the 400,000 ft altitude that was traversed by the STS-41 vehicle.

  12. The Study of Simulated Space Radiation Environment Effect on Conductive Properties of ITO Thermal Control Materials

    NASA Astrophysics Data System (ADS)

    Wei-Quan, Feng; Chun-Qing, Zhao; Zi-Cai, Shen; Yi-Gang, Ding; Fan, Zhang; Yu-Ming, Liu; Hui-Qi, Zheng; Xue, Zhao

    In order to prevent detrimental effects of ESD caused by differential surface charging of spacecraft under space environments, an ITO transparent conductive coating is often deposited on the thermal control materials outside spacecraft. Since the ITO coating is exposed in space environment, the environment effects on electrical property of ITO coatings concern designers of spacecraft deeply. This paper introduces ground tests to simulate space radiation environmental effects on conductive property of ITO coating. Samples are made of ITO/OSR, ITO/Kapton/Al and ITO/FEP/Ag thermal control coatings. Simulated space radiation environment conditions are NUV of 500ESH, 40 keV electron of 2 × 1016 е/cm2, 40 keV proton of 2.5 × 1015 p/cm2. Conductive property is surface resistivity measured in-situ in vacuum. Test results proved that the surface resistivity for all ITO coatings have a sudden decrease in the beginning of environment test. The reasons for it may be the oxygen vacancies caused by vacuum and decayed RIC caused by radiation. Degradation in conductive properties caused by irradiation were found. ITO/FEP/Ag exhibits more degradation than other two kinds. The conductive property of ITO/kapton/Al is stable for vacuum irradiation. The analysis of SEM and XPS found more crackers and less Sn and In concentration after irradiation which may be the reason for conductive property degradation.

  13. Space Weather Impacts on Spacecraft Design and Operations in Auroral Charging Environments

    NASA Technical Reports Server (NTRS)

    Minow, Joseph I.; Parker, Linda N.

    2012-01-01

    Spacecraft in low altitude, high inclination (including sun-synchronous) orbits are widely used for remote sensing of the Earth s land surface and oceans, monitoring weather and climate, communications, scientific studies of the upper atmosphere and ionosphere, and a variety of other scientific, commercial, and military applications. These systems are episodically exposed to environments characterized by a high flux of energetic (approx.1 to 10 s kilovolt) electrons in regions of very low background plasma density which is similar in some ways to the space weather conditions in geostationary orbit responsible for spacecraft charging to kilovolt levels. While it is well established that charging conditions in geostationary orbit are responsible for many anomalies and even spacecraft failures, to date there have been relatively few such reports due to charging in auroral environments. This presentation first reviews the physics of the space environment and its interactions with spacecraft materials that control auroral charging rates and the anticipated maximum potentials that should be observed on spacecraft surfaces during disturbed space weather conditions. We then describe how the theoretical values compare to the observational history of extreme charging in auroral environments and discuss how space weather impacts both spacecraft design and operations for vehicles on orbital trajectories that traverse auroral charging environments.

  14. Spacecraft Materials in the Space Flight Environment: International Space Station-May 2002 to May 2008

    NASA Astrophysics Data System (ADS)

    Golden, Johnny L.; Koontz, Steven L.; Christiansen, Eric L.; Graves, Russell F.; Lorenz, Mary J.; Alred, John W.; O'Rourke, Mary Jane E.

    2009-01-01

    The performance of ISS spacecraft materials and systems on prolonged exposure to the low-Earth orbit (LEO) space flight are reported in this paper. In-flight data, flight crew observations, and the results of ground-based test and analysis directly supporting programmatic and operational decision-making are described. The space flight environments definitions (both natural and induced) used for ISS design, material selection, and verification testing are shown, in most cases, to be more severe than the actual flight environment accounting, in part, for the outstanding performance of ISS as a long mission duration spacecraft. No significant ISS material or system failures have been attributed to spacecraft-environments interactions. Nonetheless, ISS materials and systems performance data is contributing to our understanding of spacecraft material interactions with the spaceflight environment so as to reduce cost and risk for future spaceflight projects and programs.

  15. A Review of Infrared Readout Electronics for Space Science Sensors

    NASA Technical Reports Server (NTRS)

    Pain, Bedabrata; Fossum, Eric R.

    1993-01-01

    A review of infrared readout electornics for space science sensors is presented. General requirements for scientific IR FPA readout are discussed. Specific approaches to the unit cell electronics are described with respect to operation, complexity, noise and other operating parameters. Recent achievements in IR FPA readout electronics are reviewed. Implementation technologies for realization of IR FPA readout electronics are discussed. Future directions for addressing NASA and other scientific users' needs are suggested.

  16. Logic Design Pathology and Space Flight Electronics

    NASA Technical Reports Server (NTRS)

    Katz, Richard; Barto, Rod L.; Erickson, K.

    1997-01-01

    Logic design errors have been observed in space flight missions and the final stages of ground test. The technologies used by designers and their design/analysis methodologies will be analyzed. This will give insight to the root causes of the failures. These technologies include discrete integrated circuit based systems, systems based on field and mask programmable logic, and the use computer aided engineering (CAE) systems. State-of-the-art (SOTA) design tools and methodologies will be analyzed with respect to high-reliability spacecraft design and potential pitfalls are discussed. Case studies of faults from large expensive programs to "smaller, faster, cheaper" missions will be used to explore the fundamental reasons for logic design problems.

  17. Space vehicle with artificial gravity and earth-like environment

    NASA Technical Reports Server (NTRS)

    Gray, V. H. (Inventor)

    1973-01-01

    A space vehicle adapted to provide an artificial gravity and earthlike atmospheric environment for occupants is disclosed. The vehicle comprises a cylindrically shaped, hollow pressure-tight body, one end of which is tapered from the largest diameter of the body, the other end is flat and transparent to sunlight. The vehicle is provided with thrust means which rotates the body about its longitudinal axis, generating an artificial gravity effect upon the interior walls of the body due to centrifugal forces. The walls of the tapered end of the body are maintained at a temperature below the dew point of water vapor in the body and lower than the temperature near the transparent end of the body. The controlled environment and sunlight permits an earth like environment to be maintained wherein the CO2/O2 is balanced, and food for the travelers is supplied through a natural system of plant life grown on spacecraft walls where soil is located.

  18. Survival of infectious microorganisms in space cabin environments

    NASA Technical Reports Server (NTRS)

    Vana, S. C.; Ehrlich, R.

    1974-01-01

    Aerosol survival and virulence of S. aureus and P. aeruginosa cultures isolated during exposure to simulated space cabin environment was studied using the microthread captured aerosol technique. The aerosol survival of P. aeruginosa isolates did not differ significantly from that of the original culture from which the isolates were obtained. The mean death rate of the isolates was 1.03%/min and that of the controls 1.10%/min. Similarly exposure to the 5 psi environment did not affect the virulence of P. aeruginosa. Both strains of S. aureus (IITRI and NASA) after exposure to 5 psi environment showed some degree of adaptation to this environmental stress. The aerosol death rates of the isolated organisms were 5 to 10-fold lower than of the original cultures. At the same time the virulence of the isolates was approximately 5-fold higher than that of the original culture.

  19. Artificial intelligence and the space station software support environment

    NASA Technical Reports Server (NTRS)

    Marlowe, Gilbert

    1986-01-01

    In a software system the size of the Space Station Software Support Environment (SSE), no one software development or implementation methodology is presently powerful enough to provide safe, reliable, maintainable, cost effective real time or near real time software. In an environment that must survive one of the most harsh and long life times, software must be produced that will perform as predicted, from the first time it is executed to the last. Many of the software challenges that will be faced will require strategies borrowed from Artificial Intelligence (AI). AI is the only development area mentioned as an example of a legitimate reason for a waiver from the overall requirement to use the Ada programming language for software development. The limits are defined of the applicability of the Ada language Ada Programming Support Environment (of which the SSE is a special case), and software engineering to AI solutions by describing a scenario that involves many facets of AI methodologies.

  20. The Influence of Free Space Environment in the Mission Life Cycle: Material Selection

    NASA Technical Reports Server (NTRS)

    Edwards, David L.; Burns, Howard D.; de Groh, Kim K.

    2014-01-01

    The natural space environment has a great influence on the ability of space systems to perform according to mission design specification. Understanding the natural space environment and its influence on space system performance is critical to the concept formulation, design, development, and operation of space systems. Compatibility with the natural space environment is a primary factor in determining the functional lifetime of the space system. Space systems being designed and developed today are growing in complexity. In many instances, the increased complexity also increases its sensitivity to space environmental effects. Sensitivities to the natural space environment can be tempered through appropriate design measures, material selection, ground processing, mitigation strategies, and/or the acceptance of known risks. The design engineer must understand the effects of the natural space environment on the space system and its components. This paper will discuss the influence of the natural space environment in the mission life cycle with a specific focus on the role of material selection.

  1. The Influence of Free Space Environment in the Mission Life Cycle: Material Selection

    NASA Astrophysics Data System (ADS)

    Edwards, David; Burns, Howard; De Groh, Kim

    Abstract The natural space environment has a great influence on the ability of space systems to perform according to mission design specification. Understanding the natural space environment and its influence on space system performance is critical to the concept formulation, design, development, and operation of space systems. Compatibility with the natural space environment is a primary factor in determining the functional lifetime of the space system. Space systems being designed and developed today are growing in complexity. In many instances, the increased complexity also increases its sensitivity to space environmental effects. Sensitivities to the natural space environment can be tempered through appropriate design measures, material selection, ground processing, mitigation strategies, and/or the acceptance of known risks. The design engineer must understand the effects of the natural space environment on the space system and its components. This paper will discuss the influence of the natural space environment in the mission life cycle with a specific focus on the role of material selection.

  2. Silicon Carbide Sensors and Electronics for Harsh Environment Applications

    NASA Technical Reports Server (NTRS)

    Evans, Laura J.

    2007-01-01

    Silicon carbide (SiC) semiconductor has been studied for electronic and sensing applications in extreme environment (high temperature, extreme vibration, harsh chemical media, and high radiation) that is beyond the capability of conventional semiconductors such as silicon. This is due to its near inert chemistry, superior thermomechanical and electronic properties that include high breakdown voltage and wide bandgap. An overview of SiC sensors and electronics work ongoing at NASA Glenn Research Center (NASA GRC) will be presented. The main focus will be two technologies currently being investigated: 1) harsh environment SiC pressure transducers and 2) high temperature SiC electronics. Work highlighted will include the design, fabrication, and application of SiC sensors and electronics, with recent advancements in state-of-the-art discussed as well. These combined technologies are studied for the goal of developing advanced capabilities for measurement and control of aeropropulsion systems, as well as enhancing tools for exploration systems.

  3. Space Environment Modelling with the Use of Artificial Intelligence Methods

    NASA Astrophysics Data System (ADS)

    Lundstedt, H.; Wintoft, P.; Wu, J.-G.; Gleisner, H.; Dovheden, V.

    1996-12-01

    Space based technological systems are affected by the space weather in many ways. Several severe failures of satellites have been reported at times of space storms. Our society also increasingly depends on satellites for communication, navigation, exploration, and research. Predictions of the conditions in the satellite environment have therefore become very important. We will here present predictions made with the use of artificial intelligence (AI) techniques, such as artificial neural networks (ANN) and hybrids of AT methods. We are developing a space weather model based on intelligence hybrid systems (IHS). The model consists of different forecast modules, each module predicts the space weather on a specific time-scale. The time-scales range from minutes to months with the fundamental time-scale of 1-5 minutes, 1-3 hours, 1-3 days, and 27 days. Solar and solar wind data are used as input data. From solar magnetic field measurements, either made on the ground at Wilcox Solar Observatory (WSO) at Stanford, or made from space by the satellite SOHO, solar wind parameters can be predicted and modelled with ANN and MHD models. Magnetograms from WSO are available on a daily basis. However, from SOHO magnetograms will be available every 90 minutes. SOHO magnetograms as input to ANNs will therefore make it possible to even predict solar transient events. Geomagnetic storm activity can today be predicted with very high accuracy by means of ANN methods using solar wind input data. However, at present real-time solar wind data are only available during part of the day from the satellite WIND. With the launch of ACE in 1997, solar wind data will on the other hand be available during 24 hours per day. The conditions of the satellite environment are not only disturbed at times of geomagnetic storms but also at times of intense solar radiation and highly energetic particles. These events are associated with increased solar activity. Predictions of these events are therefore

  4. High Temperature Electronics for Intelligent Harsh Environment Sensors

    NASA Technical Reports Server (NTRS)

    Evans, Laura J.

    2008-01-01

    The development of intelligent instrumentation systems is of high interest in both public and private sectors. In order to obtain this ideal in extreme environments (i.e., high temperature, extreme vibration, harsh chemical media, and high radiation), both sensors and electronics must be developed concurrently in order that the entire system will survive for extended periods of time. The semiconductor silicon carbide (SiC) has been studied for electronic and sensing applications in extreme environment that is beyond the capability of conventional semiconductors such as silicon. The advantages of SiC over conventional materials include its near inert chemistry, superior thermomechanical properties in harsh environments, and electronic properties that include high breakdown voltage and wide bandgap. An overview of SiC sensors and electronics work ongoing at NASA Glenn Research Center (NASA GRC) will be presented. The main focus will be two technologies currently being investigated: 1) harsh environment SiC pressure transducers and 2) high temperature SiC electronics. Work highlighted will include the design, fabrication, and application of SiC sensors and electronics, with recent advancements in state-of-the-art discussed as well. These combined technologies are studied for the goal of developing advanced capabilities for measurement and control of aeropropulsion systems, as well as enhancing tools for exploration systems.

  5. High versus low crewmember autonomy in space simulation environments

    NASA Astrophysics Data System (ADS)

    Kanas, Nick; Saylor, Stephanie; Harris, Matthew; Neylan, Thomas; Boyd, Jennifer; Weiss, Daniel S.; Baskin, Pamela; Cook, Colleen; Marmar, Charles

    2010-10-01

    Given the long distances involved and the kinds of activities planned, crewmembers participating in long-duration exploratory space missions such as an expedition to Mars will have more autonomy than in previous space missions. In order to study the impact of high versus low crew autonomy on crewmembers and the crew-mission control interaction, we conducted a series of pilot studies involving three space simulation settings: NEEMO missions, the Haughton-Mars Project, and the pilot phase of the Mars 500 Program. As in our previous on-orbit studies on the Mir and International Space Station, crew and mission control subjects working in missions involving these three settings completed a weekly study questionnaire that assessed mood and interpersonal interactions using the Profile of Mood States, the Group Environment Scale, and the Work Environment Scale. The Mars 500 pilot study also directly assessed individual and group autonomy. In these studies, high autonomy periods were those where crewmembers planned much of their work schedule, whereas low autonomy periods were those where mission control personnel developed the schedule, much as happens now during actual space flight conditions. Our results suggested that high work autonomy was well-received by the crews, mission goals were accomplished, and there were no adverse effects. During high autonomy periods, crewmember mood was generally reported as being better and creativity was higher, but mission control personnel reported some confusion about their work role. The crewmember group environment in the Mars 500 pilot study was dependent on the nationality mix. Despite scoring lower in work pressure overall, the four Russian crewmembers reported a greater rise in work pressure from low to high autonomy than the two Europeans. In contrast, the European crewmembers reported a greater rise in dysphoric mood in going from low to high autonomy, whereas the Russians' emotional state remained the same or slightly

  6. Operational environments for electrical power wiring on NASA space systems

    NASA Technical Reports Server (NTRS)

    Stavnes, Mark W.; Hammoud, Ahmad N.; Bercaw, Robert W.

    1994-01-01

    Electrical wiring systems are used extensively on NASA space systems for power management and distribution, control and command, and data transmission. The reliability of these systems when exposed to the harsh environments of space is very critical to mission success and crew safety. Failures have been reported both on the ground and in flight due to arc tracking in the wiring harnesses, made possible by insulation degradation. This report was written as part of a NASA Office of Safety and Mission Assurance (Code Q) program to identify and characterize wiring systems in terms of their potential use in aerospace vehicles. The goal of the program is to provide the information and guidance needed to develop and qualify reliable, safe, lightweight wiring systems, which are resistant to arc tracking and suitable for use in space power applications. This report identifies the environments in which NASA spacecraft will operate, and determines the specific NASA testing requirements. A summary of related test programs is also given in this report. This data will be valuable to spacecraft designers in determining the best wiring constructions for the various NASA applications.

  7. Space Operations Analysis Using the Synergistic Engineering Environment

    NASA Technical Reports Server (NTRS)

    Angster, Scott; Brewer, Laura

    2002-01-01

    The Synergistic Engineering Environment has been under development at the NASA Langley Research Center to aid in the understanding of the operations of spacecraft. This is accomplished through the integration of multiple data sets, analysis tools, spacecraft geometric models, and a visualization environment to create an interactive virtual simulation of the spacecraft. Initially designed to support the needs of the International Space Station, the SEE has broadened the scope to include spacecraft ranging from low-earth orbit to deep space missions. Analysis capabilities within the SEE include rigid body dynamics, kinematics, orbital mechanics, and payload operations. This provides the user the ability to perform real-time interactive engineering analyses in areas including flight attitudes and maneuvers, visiting vehicle docking scenarios, robotic operations, plume impingement, field of view obscuration, and alternative assembly configurations. The SEE has been used to aid in the understanding of several operational procedures related to the International Space Station. This paper will address the capabilities of the first build of the SEE, present several use cases of the SEE, and discuss the next build of the SEE.

  8. Radiation environments and absorbed dose estimations on manned space missions

    NASA Astrophysics Data System (ADS)

    Curtis, S. B.; Atwell, W.; Beever, R.; Hardy, A.

    In order to make an assessment of radiation risk during manned missions in space, it is necessary first to have as accurate an estimation as possible of the radiation environment within the spacecraft to which the astronauts will be exposed. Then, with this knowledge and the inclusion of body self-shielding, estimations can be made of absorbed doses for various body organs (skin, eye, blood-forming organs, etc.). A review is presented of our present knowledge of the radiation environments and absorbed doses expected for several space mission scenarios selected for our development of the new radiation protection guidelines. The scenarios selected are a 90-day mission at an altitude (450 km) and orbital inclinations (28.5°, 57° and 90°) appropriate for NASA's Space Station, a 15-day sortie to geosynchronous orbit and a 90-day lunar mission. All scenarios chosen yielded dose equivalents between five and ten rem to the blood forming organs if no large solar particle event were encountered. Such particle events could add considerable exposure particularly to the skin and eye for all scenarios except the one at 28.5° orbital inclination.

  9. Space Suit Environment Testing of the Orion Atmosphere Revitalization Technology

    NASA Technical Reports Server (NTRS)

    Lin, Amy; Sweterlitsch, Jeffrey; Cox, Marlon

    2009-01-01

    An amine-based carbon dioxide (CO2) and water vapor sorbent in pressure-swing regenerable beds has been developed by Hamilton Sundstrand and baselined for the Orion Atmosphere Revitalization System (ARS). In two previous years at this conference, reports were presented on extensive Johnson Space Center (JSC) testing of this technology in a sea-level pressure environment with simulated human metabolic loads. Another paper at this year s conference discusses similar testing with real human metabolic loads, including some closed-loop testing with emergency breathing masks. The Orion ARS is designed to also support extravehicular activity operations from a depressurized cabin. The next step in developmental testing at JSC was, therefore, to test this ARS technology in a typical closed space suit loop environment with low-pressure pure oxygen inside the process loop and vacuum outside the loop. This was the first instance of low-pressure oxygen loop testing of a new Orion ARS technology, and was conducted with simulated human metabolic loads in December 2008. The test investigated pressure drops through two different styles of prototype suit umbilical connectors and general swing-bed performance with both umbilical configurations as well as with a short jumper line installed in place of the umbilicals. Other interesting results include observations on the thermal effects of swing-bed operation in a vacuum environment and a recommendation of cycle time to maintain acceptable atmospheric CO2 and moisture levels.

  10. The Identification of Scientific Programs to Utilize the Space Environment

    NASA Technical Reports Server (NTRS)

    Kulacki, F. A.; Nerem, R. M.

    1976-01-01

    A program to identify and develop ideas for scientific experimentation on the long duration exposure facility (LDEF) was completed. Four research proposals were developed: (1) Ultra pure germanium gamma ray radiation detectors in the space environment, intended to develop and demonstrate an X-ray and gamma-ray spectroscopy system incorporating a temperature cyclable high-purity germanium detector and diode heat pipe cryogenic system for cooling, (2) growth, morphogenesis and metabolism of plant embryos in the zero-gravity environment, to investigate if the space environment induces mutations in the embryogenic cells so that mutants of commercial significance with desirable attributes may be obtained, (3) effect of zero gravity on the growth and pathogenicity of selected zoopathic fungi. It is possible that new kinds of treatment for candidiasis, and tichophytosis could eventuate from the results of the proposed studies, and (4) importance of gravity to survival strategies of small animals. Gravitational effects may be direct or mediate the selection of genetic variants that are preadapted to weightlessness.

  11. Durability of Solar Selective Coatings in a Simulated Space Environment

    NASA Technical Reports Server (NTRS)

    Jaworske, Donald A.; Lyons, Valerie (Technical Monitor)

    2002-01-01

    Solar selective coatings are being considered for heat engine and thermal switching applications on minisatellites. Such coatings must have the combined properties of high solar absorptance and low infrared emittance. High solar absorptance is needed to collect solar energy as efficiently as possible while low infrared emittance is needed to minimize radiant energy loss at operating temperature. These properties are achieved in sputter deposited thin films through the use of molecular mixtures of metal and dielectric. Solar selective coatings having a solar absorptance to infrared emittance ratio of 9 have been successfully deposited using a mixture of nickel and aluminum oxide. The space environment, however, presents some challenges for the use of materials on the exterior of spacecraft, including durability to atomic oxygen and vacuum ultraviolet radiation. To address these concerns, several candidate solar selective coatings were exposed to atomic oxygen in a plasma asher and to ultraviolet radiation in a vacuum facility equipped with calibrated deuterium lamps. The optical properties of the coatings were monitored as a function of time to evaluate their performance over long term exposure to the simulated space environment. Several coatings were found to be durable to both the atomic oxygen and the vacuum ultraviolet environments.

  12. Proton-Electron Discrimination Detector (PEDD) for space weather monitoring

    NASA Astrophysics Data System (ADS)

    Whitney, Chad M.; Johnson, Erik B.; Chen, Xiao Jie; Stapels, Christopher; Vogel, Sam; Christian, James

    2015-09-01

    Electronics used for space applications (e.g. communication satellites) are susceptible to space weather, primarily consisting of electrons and protons. As more critical equipment is used in space, a comprehensive monitoring network is needed to mitigate risks associated with radiation damage. Compact detectors suited for this requirement have been too complicated or do not provide sufficient information. As the damage from electrons (e.g. total ionizing dose effects) is significantly different compared to protons (e.g. displacement damage effects), monitors that can provide unique measurements of the dose and/or spectral information for electrons and protons separately are necessary for mission assessment to determine strategies for maintaining function. Previously, we demonstrated that the Proton-Electron Discrimination Detector (PEDD) is space-compatible and can discriminate fast electrons from protons using a diphenylanthrecene (DPA) scintillator coupled to a CMOS silicon photomultiplier (SiPM). The SiPM has a temperature dependence, and a circuit has been developed to provide a stable response as a function of temperature. The PEDD detector is scheduled to participate on the RHEME experiment to be flown on the ISS, scheduled for launch in 2016.

  13. Capabilities of the Natural Environments Branch at NASA's Marshall Space Flight Center

    NASA Technical Reports Server (NTRS)

    Edwards, David L.; Suggs, Rob; Roberts, Barry C.

    2006-01-01

    The Natural Environment Branch at NASA s Marshall Space Flight Center (MSFC) has the responsibility to provide engineering support to programs and projects in natural environments. The Natural Environments Branch (EV13) is responsible for natural environments definitions, modelling, database development and effects assessments. EV13 personnel develop requirements for flight projects and provide operational support for space and launch vehicle systems. To accomplish these responsibilities, Branch . personnel have developed modelling and analytical tools which include planetary atmospheres, meteoroids, ionizing radiation, plasmas and ionospheres, magnetic and gravitational fields, spacecraft charging modelling, and radiation effects on electronic parts. NASA s Meteoroid Environment Office is operated within the EV13 and provides meteoroid engineering models and shower forecasts to spacecraft designers and operators. This paper will describe the capabilities within the Natural Environments Effects Branch including; examples of natural environment definitions, radiation transport, output from the Global Reference Atmosphere Models for Earth, Venus, Mars, Titan, and Neptune), recent NASCAP 2K results from solar sail modelling, and meteor stream models

  14. LDEF (Prelaunch), M0004 : Space Environment Effects on Fiber Optics Systems, Tray F08

    NASA Technical Reports Server (NTRS)

    1984-01-01

    LDEF (Prelaunch), M0004 : Space Environment Effects on Fiber Optics Systems, Tray F08 The prelaunch photograph was taken in SAEF II at KSC prior to installation of the Space Environment Effects on Fiber Optic Systems Experiment on the LDEF. The Space Environment Effects on Fiber Optic Systems Experiment occupies a six (6) inch deep LDEF peripheral tray and consist of an aluminum internal support structure, an Electronic Power and Data System (EPDS), three aluminum experiment mounting plates, two aluminum cover plates, four operational digital optical data links (lengths of 48 m, 45 m and two 20 m) exposed to the space environment, three passive cabled fiber optic links (each 10 m long) with electronic components and end connectors, aluminum brackets and non-magnet stainless steel fasteners required to assemble the experiment. Four active cabled optical fiber links (one black, one blue, one yellow and one light tan), each configured in the form of a planar, helix coil, are attached to thermally isolated mounting plates with black anodized aluminum clips cushioned with silicone-rubber spacers. The three mounting plates are coated with a Catalac off-white thermal control paint, the large cover plate is coated with Chemglaze II A-276 white paint and the smaller cover plate is coated with IITRI S13G-LO white paint to meet thermal control requirements. The three passive cabled optical fiber links and all emitters, detectors and associated electronics are located in the interior volume of the tray. All cabled optical fibers terminate in connectors mounted in brackets that are located in the tray bottom or on the backside of the thermally isolated mounting plates.

  15. Comparison of Martian Radiation Environment with International Space Station

    NASA Technical Reports Server (NTRS)

    2003-01-01

    This graphic shows the radiation dose equivalent as measured by Odyssey's Martian radiation environment experiment at Mars and by instruments aboard the International Space Station, for the 11-month period from April 2002 through February 2003. The accumulated total in Mars orbit is about two and a half times larger than that aboard the Space Station. Averaged over this time period, about 10 percent of the dose equivalent at Mars is due to solar particles, although a 30 percent contribution from solar particles was seen in July 2002, when the sun was particularly active.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The radiation experiment was provided by the Johnson Space Center, Houston, Tex. Lockheed Martin Astronautics, Denver, Colo., is the prime contractor for the project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  16. Pharmaceuticals Exposed to the Space Environment: Problems and Prospects

    NASA Technical Reports Server (NTRS)

    Jaworske, Donald A.; Myers, Jerry G.

    2016-01-01

    The NASA Human Research Program (HRP) Health Countermeasures Element maintains ongoing efforts to inform detailed risks, gaps, and further questions associated with the use of pharmaceuticals in space. Most recently, the Pharmacology Risk Report, released in 2010, illustrates the problems associated with maintaining pharmaceutical efficacy. Since the report, one key publication includes evaluation of pharmaceutical products stored on the International Space Station (ISS). This study shows that selected pharmaceuticals on ISS have a shorter shelf-life in space than corresponding terrestrial controls. The HRP Human Research Roadmap for planetary exploration identifies the risk of ineffective or toxic medications due to long-term storage during missions to Mars. The roadmap also identifies the need to understand and predict how pharmaceuticals will behave when exposed to radiation for long durations. Terrestrial studies of returned samples offer a start for predictive modeling. This paper shows that pharmaceuticals returned to Earth for post-flight analyses are amenable to a Weibull distribution analysis in order to support probabilistic risk assessment modeling. The paper also considers the prospect of passive payloads of key pharmaceuticals on sample return missions outside of Earth's magnetic field to gather additional statistics. Ongoing work in radiation chemistry suggests possible mitigation strategies where future work could be done at cryogenic temperatures to explore methods for preserving the strength of pharmaceuticals in the space radiation environment, perhaps one day leading to an architecture where pharmaceuticals are cached on the Martian surface and preserved cryogenically.

  17. Interaction-Free Quantum Electron Microscope in Free-Space

    NASA Astrophysics Data System (ADS)

    Yang, Yujia; Kim, Chung-Soo; Hobbs, Richard; Manfrinato, Vitor; Celiker, Orhan; Kruit, Pieter; Berggren, Karl

    2015-03-01

    We propose the design and theoretical analysis of a quantum electron microscope (QEM), which utilizes interaction-free quantum measurement with electrons for nanoscale imaging. The QEM can be used to image electron-irradiation-sensitive materials, such as biological samples, with a high resolution and low radiation damage. Our QEM scheme is an electron interferometer with a storage resonator. The incoming electron beam is asymmetrically split into a strong reference beam and a weak sample beam, both of which are stored in the resonator. Only the weak sample beam transmits through the sample for multiple times. We propose to build the QEM with free-space electron optics. We develop a scattering matrix method to theoretically analyze the contrast mechanism, radiation damage, and measurement accuracy. We propose an electron-mirror-based storage resonator and we have performed electron optics simulation of electron trajectories within the resonator. We also report experimental implementation and characterization of the electron beam-splitter to be used in the QEM. Thin crystals fabricated with focused ion beam and nano-gratings fabricated with electron-beam lithography are two candidate beam-splitters, both of which are characterized by electron diffraction. This work is funded by Gordon and Betty Moore Foundation.

  18. Atmospheric environment for Space Shuttle (STS-37) launch

    NASA Technical Reports Server (NTRS)

    Jasper, G. L.; Batts, G. W.

    1991-01-01

    A summary of selected atmospheric conditions observed near Space Shuttle STS-37 launch time on 5 Apr. 1991 at KSC is presented. Values of ambient pressure, temperature, moisture, ground winds, visual observations (clouds), and winds aloft are included. The sequence of prelaunch Jimsphere-measured vertical wind profiles is given. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-37 vehicle ascent was constructed. The STS-37 ascent atmospheric data tape was constructed by Marshall Space Flight Center's Earth Science and Applications Division to provide an internally consistent data set for use in postflight performance assessments and represents the best estimate of the launch environment to the 400,000 ft. altitude that was traversed by the STS-37 vehicle.

  19. Atmospheric environment for space shuttle (STS-34) launch

    NASA Technical Reports Server (NTRS)

    Jasper, G. L.; Batts, G. W.

    1989-01-01

    A summary of selected atmospheric conditions observed near space shuttle STS-34 launch time on October 18, 1989, at Kennedy Space Center, Florida is presented. Values of ambient pressure, temperature, moisture, ground winds, visual observations (clouds), and winds aloft are included. The sequence of pre-launch Jimsphere-measured vertical wind profiles is given. The final atmospheric tape, which consists of wind and thermodynamic parameters vs. altitude, for STS-34 vehicle ascent was constructed to provide an internally consistent data set for use in post-flight performance assessments. It represents the best estimates of the launch environment to the 400,000 feet altitude that was traversed by the STS-34 vehicle.

  20. Atmospheric environment for space shuttle (STS-36) launch

    NASA Technical Reports Server (NTRS)

    Jasper, G. L.; Batts, G. W.

    1990-01-01

    A summary of selected atmospheric conditions observed near space shuttle STS-36 launch time on February 28, 1990, at Kennedy Space Center, Florida was presented. STS-36 carried a Department of Defense payload and the flight azimuth is not known. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of pre-launch Jimsphere-measured vertical wind profiles is given. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-36 vehicle ascent was constructed. The STS-36 ascent atmospheric data tape was constructed to provide an internally consistent data set for use in postflight performance assessments and represent the best estimate of the launch environment to the 400,000 feet altitude that was traversed by the STS-36 vehicle.

  1. Atmospheric Environment for Space Shuttle (STS-28) Launch

    NASA Technical Reports Server (NTRS)

    Jasper, G. L.; Batts, G. W.

    1990-01-01

    A summary is presented of selected atmospheric conditions observed near Space Shuttle STS-28 launch time on August 8, 1989. STS-28 carried a Department of Defense payload and the flight azimuth is denoted by a reference flight azimuth, since the actual flight azimuth is not known. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere-measured vertical wind profiles is given. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-28 vehicle ascent was constructed and represents the best estimate of the launch environment to 400,000 ft altitude that was traversed by the STS-28 vehicle. The STS-28 ascent atmospheric data tape was constructed by Marshall Space Flight Center's Earth Science and Applications Division to provide an internally consistent data set for use in post-flight performance assessments.

  2. Atmospheric environment for Space Shuttle (STS-31) launch

    NASA Technical Reports Server (NTRS)

    Jasper, G. L.; Batts, G. W.

    1990-01-01

    A summary of selected atmospheric conditions observed near space shuttle STS-31 launch time on April 24, 1990, at Kennedy Space Center, Florida, are presented. Values of ambient pressure, temperature, moisture, ground winds, visual observations (clouds), and winds aloft are included. The sequence of pre-launch Jimsphere-measured vertical wind profiles is also presented. The final atmospheric tape, which consists if wind and thermodynamic parameters versus altitude, for STS-31 vehicle ascent was constructed. The STS-31 ascent atmospheric data tape was constructed to provide an internally consistent data set for use in postflight performance assessments and represent the best estimated of the launch environment to the 400,000 feet altitude that was traversed by the STS-31 vehicle.

  3. Atmospheric environment for Space Shuttle (STS-32) launch

    NASA Technical Reports Server (NTRS)

    Jasper, G. L.; Batts, G. W.

    1990-01-01

    A summary of selected atmospheric conditions observed near space shuttle STS-32 launch time on January 9, 1990, at Kennedy Space Center, Florida, are presented. Values of ambient pressure, temperature, moisture, ground winds, visual observations (clouds), and winds aloft are included. The sequence of pre-launch Jimsphere-measured vertical wind profiles is also presented. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-32 vehicle ascent was constructed. The STS-32 ascent atmospheric data tape was constructed to provide an internally consistent data set for use in postflight performance assessments and represents the best estimate of the launch environment that was traversed by the STS-32 vehicle.

  4. Atmospheric environment for Space Shuttle Atlantis (STS-39) launch

    NASA Technical Reports Server (NTRS)

    Jasper, G. L.; Batts, G. W.

    1992-01-01

    A summary is presented of selected atmospheric conditions observed near space shuttle Atlantis STS-39 launch time on 28 April 1991, at Kennedy Space Center, FL. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere measured vertical wind profiles is given. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-39 vehicle ascent was constructed. The STS-39 ascent atmospheric data tape was constructed by NASA-Marshall to provide an internally consistent data set for use in postflight performance assessments and represents the best estimate of the launch environment to the 400,000 ft altitude that was traversed by the STS-39 vehicle.

  5. Worst-case space radiation environments for geocentric missions

    NASA Technical Reports Server (NTRS)

    Stassinopoulos, E. G.; Seltzer, S. M.

    1976-01-01

    Worst-case possible annual radiation fluences of energetic charged particles in the terrestrial space environment, and the resultant depth-dose distributions in aluminum, were calculated in order to establish absolute upper limits to the radiation exposure of spacecraft in geocentric orbits. The results are a concise set of data intended to aid in the determination of the feasibility of a particular mission. The data may further serve as guidelines in the evaluation of standard spacecraft components. Calculations were performed for each significant particle species populating or visiting the magnetosphere, on the basis of volume occupied by or accessible to the respective species. Thus, magnetospheric space was divided into five distinct regions using the magnetic shell parameter L, which gives the approximate geocentric distance (in earth radii) of a field line's equatorial intersect.

  6. Simulation framework for space environment ground test fidelity

    NASA Astrophysics Data System (ADS)

    Cline, Jason A.; Quenneville, Jason; Taylor, Ramona S.; Deschenes, Timothy; Braunstein, Matthew; Legner, Hartmut; Green, B. D.

    2013-09-01

    We present initial work to develop an extensible model for spacecraft environmental interactions. The starting point for model development is a rarefied gas dynamics model for hyperthermal atomic oxygen. The space envi- ronment produces a number of challenging stimuli, including atomic oxygen, but also charged particles, magnetic fields, spacecraft charging, ultraviolet radiation, micrometeoroids, and cryogenic temperatures. Moreover, the responses of spacecraft to combinations or sequences of these stimuli are different from their responses to single stimuli. New multi-stimulus test facilities such as the Space Threat Assessment Testbed at the USAF Arnold Engi- neering Development Complex make understanding the similarities and differences between terrestrial test and on-orbit conditions increasingly relevant. The extensible model framework under development is intended to host the variety of models needed to describe the multiphysics environment, allowing them to interact to produce a consistent unified picture. The model framework will host modules that can be validated individually or in combination.

  7. Applications and fabrication of flasks for hostile environment electronics

    SciTech Connect

    Randall, R.R.; Craik, G.C.

    1988-02-01

    The use of electronic instrumentation in a high temperature environment such as a wellbore requires a choice between two design techniques. The preferred technique is to design a system with high temperature electronics. When there are obstacles to such a design, a workable second choice is to use a Dewar flask to provide a protected environment. Design options for building a flask and engineering information on how to use flasks is provided. Selected well logging services are made possible by using Dewar flask technology.

  8. Process material management in the Space Station environment

    NASA Technical Reports Server (NTRS)

    Perry, J. L.; Humphries, W. R.

    1988-01-01

    The Space Station will provide a unique facility for conducting material-processing and life-science experiments under microgravity conditions. These conditions place special requirements on the U.S. Laboratory for storing and transporting chemicals and process fluids, reclaiming water from selected experiments, treating and storing experiment wastes, and providing vacuum utilities. To meet these needs and provide a safe laboratory environment, the Process Material Management System (PMMS) is being developed. Preliminary design requirements and concepts related to the PMMS are addressed, and the MSFC PMMS breadboard test facility and a preliminary plan for validating the overall system design are discussed.

  9. Terrestrial Applications of Extreme Environment Stirling Space Power Systems

    NASA Technical Reports Server (NTRS)

    Dyson, Rodger. W.

    2012-01-01

    NASA has been developing power systems capable of long-term operation in extreme environments such as the surface of Venus. This technology can use any external heat source to efficiently provide electrical power and cooling; and it is designed to be extremely efficient and reliable for extended space missions. Terrestrial applications include: use in electric hybrid vehicles; distributed home co-generation/cooling; and quiet recreational vehicle power generation. This technology can reduce environmental emissions, petroleum consumption, and noise while eliminating maintenance and environmental damage from automotive fluids such as oil lubricants and air conditioning coolant. This report will provide an overview of this new technology and its applications.

  10. Telescience Testbed Pilot Project - Evaluation environment for Space Station operations

    NASA Technical Reports Server (NTRS)

    Wiskerchen, Michael J.; Leiner, Barry M.

    1988-01-01

    The objectives of the Telescience Testbed Pilot Program (TTPP) are discussed. The purpose of the TTPP, which involves 15 universities in cooperation with various NASA centers, is to demonstrate the utility of a user-oriented rapid prototyping testbed approach to developing and refining science requirements and validation concepts and approaches for the information systems of the Space Station era and beyond. It is maintained that the TTPP provides an excellent environment, with low programmatic schedule and budget risk, for testing and evaluating new operations concepts and technologies.

  11. Extreme Events in GOES Space Environment Monitor Data 1974 - 2011

    NASA Astrophysics Data System (ADS)

    Wilkinson, D. C.; Sundaravel, A. S.

    2011-12-01

    The GOES satellite mission has monitored the space environment from geostationary orbit since the launch of SMS-1 in 1974. The data archive includes data from the X-ray Sensor, Energetic Particle Sensor and Magnetometer. These instruments remained relatively consistent from satellite to satellite making it possible to compare events separated by many years. In addition to graphical displays of extreme events, daily values will display long term trends in these data. This presentation will incorporate time-averages from 1974 - 1985 which were made available to the public for the first time this Fall.

  12. Electron cloud and space charge effects in the Fermilab Booster

    SciTech Connect

    Ng, K.Y.; /Fermilab

    2007-06-01

    The stable region of the Fermilab Booster beam in the complex coherent-tune-shift plane appears to have been shifted far away from the origin by its intense space charge making Landau damping appear impossible. Simulations reveal a substantial buildup of electron cloud in the whole Booster ramping cycle, both inside the unshielded combined-function magnets and the beam pipes joining the magnets, whenever the secondary-emission yield (SEY) is larger than {approx}1.6. The implication of the electron-cloud effects on the space charge and collective instabilities of the beam is investigated.

  13. Atomically resolved real-space imaging of hot electron dynamics

    PubMed Central

    Lock, D.; Rusimova, K. R.; Pan, T. L.; Palmer, R. E.; Sloan, P. A.

    2015-01-01

    The dynamics of hot electrons are central to understanding the properties of many electronic devices. But their ultra-short lifetime, typically 100 fs or less, and correspondingly short transport length-scale in the nanometre range constrain real-space investigations. Here we report variable temperature and voltage measurements of the nonlocal manipulation of adsorbed molecules on the Si(111)-7 × 7 surface in the scanning tunnelling microscope. The range of the nonlocal effect increases with temperature and, at constant temperature, is invariant over a wide range of electron energies. The measurements probe, in real space, the underlying hot electron dynamics on the 10 nm scale and are well described by a two-dimensional diffusive model with a single decay channel, consistent with 2-photon photo-emission (2PPE) measurements of the real time dynamics. PMID:26387703

  14. Atomically resolved real-space imaging of hot electron dynamics.

    PubMed

    Lock, D; Rusimova, K R; Pan, T L; Palmer, R E; Sloan, P A

    2015-01-01

    The dynamics of hot electrons are central to understanding the properties of many electronic devices. But their ultra-short lifetime, typically 100 fs or less, and correspondingly short transport length-scale in the nanometre range constrain real-space investigations. Here we report variable temperature and voltage measurements of the nonlocal manipulation of adsorbed molecules on the Si(111)-7 × 7 surface in the scanning tunnelling microscope. The range of the nonlocal effect increases with temperature and, at constant temperature, is invariant over a wide range of electron energies. The measurements probe, in real space, the underlying hot electron dynamics on the 10 nm scale and are well described by a two-dimensional diffusive model with a single decay channel, consistent with 2-photon photo-emission (2PPE) measurements of the real time dynamics. PMID:26387703

  15. Atomically resolved real-space imaging of hot electron dynamics

    NASA Astrophysics Data System (ADS)

    Lock, D.; Rusimova, K. R.; Pan, T. L.; Palmer, R. E.; Sloan, P. A.

    2015-09-01

    The dynamics of hot electrons are central to understanding the properties of many electronic devices. But their ultra-short lifetime, typically 100 fs or less, and correspondingly short transport length-scale in the nanometre range constrain real-space investigations. Here we report variable temperature and voltage measurements of the nonlocal manipulation of adsorbed molecules on the Si(111)-7 × 7 surface in the scanning tunnelling microscope. The range of the nonlocal effect increases with temperature and, at constant temperature, is invariant over a wide range of electron energies. The measurements probe, in real space, the underlying hot electron dynamics on the 10 nm scale and are well described by a two-dimensional diffusive model with a single decay channel, consistent with 2-photon photo-emission (2PPE) measurements of the real time dynamics.

  16. Phase-space Dynamics of Runaway Electrons In Tokamaks

    SciTech Connect

    Xiaoyin Guan, Hong Qin, and Nathaniel J. Fisch

    2010-08-31

    The phase-space dynamics of runaway electrons is studied, including the influence of loop voltage, radiation damping, and collisions. A theoretical model and a numerical algorithm for the runaway dynamics in phase space are developed. Instead of standard integrators, such as the Runge-Kutta method, a variational symplectic integrator is applied to simulate the long-term dynamics of a runaway electron. The variational symplectic integrator is able to globally bound the numerical error for arbitrary number of time-steps, and thus accurately track the runaway trajectory in phase space. Simulation results show that the circulating orbits of runaway electrons drift outward toward the wall, which is consistent with experimental observations. The physics of the outward drift is analyzed. It is found that the outward drift is caused by the imbalance between the increase of mechanical angular momentum and the input of toroidal angular momentum due to the parallel acceleration. An analytical expression of the outward drift velocity is derived. The knowledge of trajectory of runaway electrons in configuration space sheds light on how the electrons hit the first wall, and thus provides clues for possible remedies.

  17. Creating the Deep Space Environment for Testing the James Webb Space Telescope at the Johnson Space Center's Chamber A

    NASA Technical Reports Server (NTRS)

    Homan, Jonathan L.; Cerimele, Mary P.; Montz, Michael E.

    2012-01-01

    Chamber A is the largest thermal vacuum chamber at the Johnson Space Center and is one of the largest space environment chambers in the world. The chamber is 19.8 m (65 ft) in diameter and 36.6 m (120 ft) tall and is equipped with cryogenic liquid nitrogen panels (shrouds) and gaseous helium shrouds to create a simulated space environment. It was originally designed and built in the mid 1960's to test the Apollo Command and Service Module and several manned tests were conducted on that spacecraft, contributing to the success of the program. The chamber has been used since that time to test spacecraft active thermal control systems, Shuttle DTO, DOD, and ESA hardware in simulated Low Earth Orbit (LEO) conditions. NASA is now moving from LEO towards exploration of locations with environments approaching those of deep space. Therefore, Chamber A has undergone major modifications to enable it to simulate these deeper space environments. Environmental requirements were driven, and the modifications were funded, by the James Webb Space Telescope program, and this telescope which will orbit Solar/Earth L2, will be the first test article to benefit from the chamber s new capabilities. To accommodate JWST, the Chamber A high vacuum system has been modernized, additional LN2 shrouds have been installed, the liquid nitrogen system has been modified to remove dependency on electrical power and increase its reliability, a new helium shroud/refrigeration system has been installed to create a colder more stable and uniform heat sink and, the controls have been updated to increase the level of automation and improve operator interfaces. Testing of these major modifications was conducted in August 2012 and this initial test was very successful, with all major systems exceeding their performance requirements. This paper will outline the changes in the overall environmental requirements, discuss the technical design data that was used in the decisions leading to the extensive

  18. Creating the Deep Space Environment for Testing the James Webb Space Telescope at NASA Johnson Space Center's Chamber A

    NASA Technical Reports Server (NTRS)

    Homan, Jonathan L.; Cerimele, Mary P.; Montz, Michael E.; Bachtel, Russell; Speed, John; O'Rear, Patrick

    2013-01-01

    Chamber A is the largest thermal vacuum chamber at the Johnson Space Center and is one of the largest space environment chambers in the world. The chamber is 19.8 m (65 ft.) in diameter and 36.6 m (120 ft.) tall and is equipped with cryogenic liquid nitrogen panels (shrouds) and gaseous helium shrouds to create a simulated space environment. It was originally designed and built in the mid 1960 s to test the Apollo Command and Service Module and several manned tests were conducted on that spacecraft, contributing to the success of the program. The chamber has been used since that time to test spacecraft active thermal control systems, Shuttle DTO, DOD, and ESA hardware in simulated Low Earth Orbit (LEO) conditions. NASA is now moving from LEO towards exploration of locations with environments approaching those of deep space. Therefore, Chamber A has undergone major modifications to enable it to simulate these deeper space environments. Environmental requirements were driven, and modifications were funded by the James Webb Space Telescope program, and this telescope, which will orbit Solar/Earth L2, will be the first test article to benefit from the chamber s new capabilities. To accommodate JWST, the Chamber A high vacuum system has been modernized, additional LN2 shrouds have been installed, the liquid nitrogen system has been modified to minimize dependency on electrical power and increase its reliability, a new helium shroud/refrigeration system has been installed to create a colder more stable and uniform heat sink, and the controls have been updated to increase the level of automation and improve operator interfaces. Testing of these major modifications was conducted in August of 2012 and this initial test was very successful, with all major systems exceeding their performance requirements. This paper will outline the changes in overall environmental requirements, discuss the technical design data that was used in the decisions leading to the extensive

  19. Creating the Deep Space Environment for Testing the James Webb Space Telescope (JWST) at NASA Johnson Space Center's Chamber A

    NASA Technical Reports Server (NTRS)

    Homan, Jonathan L.; Cerimele, Mary P.; Montz, Michael E.; Bachtel, Russell; Speed, John; O'Rear, Patrick

    2013-01-01

    Chamber A is the largest thermal vacuum chamber at the Johnson Space Center and is one of the largest space environment chambers in the world. The chamber is 19.8 m (65 ft) in diameter and 36.6 m (120 ft) tall and is equipped with cryogenic liquid nitrogen panels (shrouds) and gaseous helium shrouds to create a simulated space environment. It was originally designed and built in the mid 1960 s to test the Apollo Command and Service Module and several manned tests were conducted on that spacecraft, contributing to the success of the program. The chamber has been used since that time to test spacecraft active thermal control systems, Shuttle DTO, DOD, and ESA hardware in simulated Low Earth Orbit (LEO) conditions. NASA is now moving from LEO towards exploration of locations with environments approaching those of deep space. Therefore, Chamber A has undergone major modifications to enable it to simulate these deeper space environments. Environmental requirements were driven, and modifications were funded by the James Webb Space Telescope program, and this telescope which will orbit Solar/Earth L2, will be the first test article to benefit from the chamber s new capabilities. To accommodate JWST, the Chamber A high vacuum system has been modernized, additional LN2 shrouds have been installed, the liquid nitrogen system has been modified to remove dependency on electrical power and increase its reliability, a new helium shroud/refrigeration system has been installed to create a colder more stable and uniform heat sink, and the controls have been updated to increase the level of automation and improve operator interfaces. Testing of these major modifications was conducted in August of 2012 and this initial test was very successful, with all major systems exceeding their performance requirements. This paper will outline the changes in overall environmental requirements, discuss the technical design data that was used in the decisions leading to the extensive modifications

  20. Optical Analysis of Transparent Polymeric Material Exposed to Simulated Space Environment

    NASA Technical Reports Server (NTRS)

    Edwards, David L.; Finckenor, Miria M.

    1999-01-01

    Transparent polymeric materials are being designed and utilized as solar concentrating lenses for spacecraft power and propulsion systems. These polymeric lenses concentrate solar energy onto energy conversion devices such as solar cells and thermal energy systems. The conversion efficiency is directly related to the transmissivity of the polymeric lens. The Environmental Effects Group of the Marshall Space Flight Center's Materials, Processes, and Manufacturing Department exposed a variety of materials to a simulated space environment and evaluated them for an, change in optical transmission. These materials include Lexan(TM), polyethylene terephthalate (PET). several formulations of Tefzel(TM). and Teflon(TM), and silicone DC 93-500. Samples were exposed to a minimum of 1000 Equivalent Sun Hours (ESH) of near-UV radiation (250 - 400 nm wavelength). Data will be presented on materials exposed to charged particle radiation equivalent to a five-year dose in geosynchronous orbit. These exposures were performed in MSFC's Combined Environmental Effects Test Chamber, a unique facility with the capability to expose materials simultaneously or sequentially to protons, low-energy electrons, high-energy electrons, near UV radiation and vacuum UV radiation.Prolonged exposure to the space environment will decrease the polymer film's transmission and thus reduce the conversion efficiency. A method was developed to normalize the transmission loss and thus rank the materials according to their tolerance to space environmental exposure. Spectral results and the material ranking according to transmission loss are presented.

  1. The simulated space proton environment for radiation effects on Space Telescope Imaging Spectrograph (STIS)

    NASA Technical Reports Server (NTRS)

    Becher, Jacob; Fowler, Walter

    1992-01-01

    The space telescope imaging spectrograph (STIS) is a second generation instrument planned for the Hubble Space Telescope (HST) which is currently in orbit. Candidate glasses and other transmitting materials are being considered for order sorters, in-flight calibration filters, detector windows, and calibration lamps. The glasses for in-flight calibration filters showed significant drop in UV transmission, but can probably still be used on STIS. The addressed topics include the Hubble radiation environment, simulation of orbital exposure at Harvard Cyclotron Laboratory, measurement of spectral transmission, and comments on individual samples.

  2. Analysis of the Thermo-Elastic Response of Space Reflectors to Simulated Space Environment

    NASA Astrophysics Data System (ADS)

    Allegri, G.; Ivagnes, M. M.; Marchetti, M.; Poscente, F.

    2002-01-01

    The evaluation of space environment effects on materials and structures is a key matter to develop a proper design of long duration missions: since a large part of satellites operating in the earth orbital environment are employed for telecommunications, the development of space antennas and reflectors featured by high dimensional stability versus space environment interactions represents a major challenge for designers. The structural layout of state of the art space antennas and reflectors is very complex, since several different sensible elements and materials are employed: particular care must be placed in evaluating the actual geometrical configuration of the reflectors operating in the space environment, since very limited distortions of the designed layout can produce severe effects on the quality of the signal both received and transmitted, especially for antennas operating at high frequencies. The effects of thermal loads due to direct sunlight exposition and to earth and moon albedo can be easily taken into account employing the standard methods of structural analysis: on the other hand the thermal cycling and the exposition to the vacuum environment produce a long term damage accumulation which affects the whole structure. The typical effects of the just mentioned exposition are the outgassing of polymeric materials and the contamination of the exposed surface, which can affect sensibly the thermo-mechanical properties of the materials themselves and, therefore, the structural global response. The main aim of the present paper is to evaluate the synergistic effects of thermal cycling and of the exposition to high vacuum environment on an innovative antenna developed by Alenia Spazio S.p.a.: to this purpose, both an experimental and numerical research activity has been developed. A complete prototype of the antenna has been exposed to the space environment simulated by the SAS facility: this latter is constituted by an high vacuum chamber, equipped by

  3. Mutagenesis of Bacillus subtilis spores exposed to simulated space environment

    NASA Astrophysics Data System (ADS)

    Munakata, N.; Natsume, T.; Takahashi, K.; Hieda, K.; Panitz, C.; Horneck, G.

    Bacterial spores can endure in a variety of extreme earthly environments. However, some conditions encountered during the space flight could be detrimental to DNA in the spore, delimiting the possibility of transpermia. We investigate the genetic consequences of the exposure to space environments in a series of preflight simulation project of EXPOSE. Using Bacillus subtilis spores of repair-proficient HA101 and repair-deficient TKJ6312 strains, the mutations conferring resistance to rifampicin were detected, isolated and sequenced. Most of the mutations were located in a N-terminal region of the rpoB gene encoding RNA polymerase beta-subunit. Among several potentially mutagenic factors, high vacuum, UV radiation, heat, and accelerated heavy ions induced mutations with varying efficiencies. A majority of mutations induced by vacuum exposure carried a tandem double-base change (CA to TT) at a unique sequence context of TCAGC. Results indicate that the vacuum and high temperature may act synergistically for the induction of mutations.

  4. Increasing Importance of Material Electrical Interaction with the Space Environment

    NASA Technical Reports Server (NTRS)

    Carruth, M. R., Jr.; Vaughn, Jason

    2000-01-01

    The electrical properties of materials have always been important for spacecraft in charging environments. However, in recent years consideration of interactions of materials and systems with the plasma environment has become more and more important in spacecraft design. This has primarily been driven by independent factors including increase in power and high voltage power systems, operation of tethered satellites, and science requirements for electrostatic clean spacecraft. Increased need for power has led to increased operating voltages for spacecraft. The Upper Atmospheric Research Satellite (UARS) was one of the first to operate at near 100 V solar array potential and demonstrate that the spacecraft floated nearly the entire voltage negative of the ionospheric plasma. The high voltage, 160 V, of the solar arrays on the International Space Station (ISS) led to the requirement to have a plasma contactor to control structure potential relative to the local plasma. Issues such as sputtering, dielectric breakdown, capacitive energy storage in the structure, space debris impact induced arcs and other arcing mechanisms had to be addressed. Recently commercial satellites, driven to higher voltages for efficiency, have experienced arcing problems which led to severe, permanent power degradation. The first tethered satellite, Tethered Satellite System (TSS), was deployed from the Space Shuttle. A conductive coating was developed which provided a low resistivity and also the required solar absorptivity and emittance. Other tether systems are being designed which will have similar requirements but also long life and "bare tether" designs are also being built for flight experiments. The wire requires an electrically conductive coating with proper thermal control properties, which a bare wire doesn't possess. Increasing sophistication of scientific instruments and measurements which scientists want to make have led to increasing requirements for conducting thermal control

  5. Effects of the space environment on the health and safety of space workers

    NASA Technical Reports Server (NTRS)

    Hull, W. E.

    1980-01-01

    Large numbers of individuals are required to work in space to assemble and operate a Solar Power Satellite. The physiological and behavioral consequences for large groups of men and women who perform complex tasks in the vehicular or extravehicular environments over long periods of orbital stay time were considered. The most disturbing consequences of exposure to the null gravity environment found relate to: (1) a generalized cardiovascular deconditioning along with loss of a significant amount of body fluid volume; (2) loss of bone minerals and muscle mass; and (3) degraded performance of neutral mechanisms which govern equilibrium and spatial orientation.

  6. Effects of the space environment on the health and safety of space workers

    NASA Astrophysics Data System (ADS)

    Hull, W. E.

    1980-07-01

    Large numbers of individuals are required to work in space to assemble and operate a Solar Power Satellite. The physiological and behavioral consequences for large groups of men and women who perform complex tasks in the vehicular or extravehicular environments over long periods of orbital stay time were considered. The most disturbing consequences of exposure to the null gravity environment found relate to: (1) a generalized cardiovascular deconditioning along with loss of a significant amount of body fluid volume; (2) loss of bone minerals and muscle mass; and (3) degraded performance of neutral mechanisms which govern equilibrium and spatial orientation.

  7. Expression and Association Rights of School Employees in Electronic Environments

    ERIC Educational Resources Information Center

    Bathon, Justin M.

    2012-01-01

    Many of the recent legal decisions regarding public employee expression, particularly in electronic environments, run counter to the culture being facilitated by the Internet. This article uses a legal analysis to examine recent decisions and then considers those legal positions within the context of digital expression. (Contains 2 notes.)

  8. Sherlock: A Coached Practice Environment for an Electronics Troubleshooting Job.

    ERIC Educational Resources Information Center

    Lesgold, Alan; And Others

    "Sherlock" is a computer-based, supported practice environment for a complex troubleshooting job in Air Force electronics. The program was developed to raise the level of troubleshooting knowledge of avionics technicians. This describes the training problem for which Sherlock was developed, the principles behind its development, and its…

  9. Volume Resistivity Measurement of Insulating Material in Space Environment Simulated Condition

    NASA Astrophysics Data System (ADS)

    Watanabe, Rikio; Miyake, Hiroaki; Tanaka, Yasuhiro; Nitta, Kumi

    Volume resistivities of polyimide film under simulated space environment are measured with “charge storage decay method.” The test material was irradiated by electron beam in a vacuum chamber to simulate space environment. Volume resistivity is calculated from the surface potential decay time constant after stopping electron irradiation. This is called “charge storage decay method” and is shown to be the preferred method to determine resistivities of highly insulating materials. As a result of experiments, we have found that volume resistivity of polyimide film is in order of 1016 Ωm, which is one order higher than the result from the conventional resistivity measurement method prescribed in JIS or ASTM. Higher resistivity requires much longer field relaxation time after injection of electron to dissipate through the material. Thus, charging analysis of spacecraft needs to consider this higher resistivity. The effect of injection energy of electron is also examined and it is found that the higher the energy is, the faster the charge decay become.

  10. Geant4 Predictions of Energy Spectra in Typical Space Radiation Environment

    NASA Technical Reports Server (NTRS)

    Sabra, M. S.; Barghouty, A. F.

    2014-01-01

    Accurate knowledge of energy spectra inside spacecraft is important for protecting astronauts as well as sensitive electronics from the harmful effects of space radiation. Such knowledge allows one to confidently map the radiation environment inside the vehicle. The purpose of this talk is to present preliminary calculations for energy spectra inside a spherical shell shielding and behind a slab in typical space radiation environment using the 3D Monte-Carlo transport code Geant4. We have simulated proton and iron isotropic sources and beams impinging on Aluminum and Gallium arsenide (GaAs) targets at energies of 0.2, 0.6, 1, and 10 GeV/u. If time permits, other radiation sources and beams (_, C, O) and targets (C, Si, Ge, water) will be presented. The results are compared to ground-based measurements where available.

  11. Implications for space radiation environment models from CREAM & CREDO measurements over half a solar cycle.

    PubMed

    Dyer, C S; Truscott, P R; Peerless, C L; Watson, C J; Evans, H E; Knight, P; Cosby, M; Underwood, C; Cousins, T; Noulty, R; Maag, C

    1999-10-01

    Flight data obtained between 1990 and 1997 from the Cosmic Radiation Environment Monitors CREAM & CREDO carried on UoSAT-3, Space Shuttle, STRV-1a (Space Technology Research Vehicle) and APEX (Advanced Photovoltaic and Electronics Experiment Spacecraft) provide coverage over half a solar cycle. The modulation of cosmic rays and evolution of the South Atlantic Anomaly are observed, the former comprising a factor of three increase at high latitudes and the latter a general increase accompanied by a north-westward drift. Comparison of particle fluxes and linear energy transfer (LET) spectra is made with improved environment & radiation transport calculations which account for shield distributions and secondary particles. While there is an encouraging convergence between predictions and observations, significant improvements are still required, particularly in the treatment of locally produced secondary particles. Solar-particle events during this time period have LET spectra significantly below the October 1989 event which has been proposed as a worst case model. PMID:11542668

  12. Geant4 predictions of energy spectra in typical space radiation environment

    NASA Astrophysics Data System (ADS)

    Sabra, M. S.; Barghouty, A. F.

    2014-03-01

    Accurate knowledge of energy spectra inside spacecraft is important for protecting astronauts as well as sensitive electronics from the harmful effects of space radiation. Such knowledge allows one to confidently map the radiation environment inside the vehicle. The purpose of this talk is to present preliminary calculations for energy spectra inside a spherical shell shielding and behind a slab in typical space radiation environment using the 3D Monte-Carlo transport code Geant4. We have simulated proton and iron isotropic sources and beams impinging on Aluminum and Gallium arsenide (GaAs) targets at energies of 0.2, 0.6, 1, and 10 GeV/u. If time permits, other radiation sources and beams (α, C, O) and targets (C, Si, Ge, water) will be presented. The results are compared to ground-based measurements where available.

  13. Electrochemical Investigation of Corrosion in the Space Shuttle Launch Environment

    NASA Technical Reports Server (NTRS)

    Calle, L. M.

    2004-01-01

    Corrosion studies began at NASA/Kennedy Space Center in 1966 during the Gemini/Apollo Programs with the evaluation of long-term protective coatings for the atmospheric protection of carbon steel. An outdoor exposure facility on the beach near the launch pad was established for this purpose at that time. The site has provided over 35 years of technical information on the evaluation of the long-term corrosion performance of many materials and coatings as well as on maintenance procedures. Results from these evaluations have helped NASA find new materials and processes that increase the safety and reliability of our flight hardware, launch structures, and ground support equipment. The launch environment at the Kennedy Space Center (KSC) is extremely corrosive due to the combination of ocean salt spray, heat, humidity, and sunlight. With the introduction of the Space Shuttle in 1981, the already highly corrosive conditions at the launch pad were rendered even more severe by the acidic exhaust from the solid rocket boosters. It has been estimated that 70 tons of hydrochloric acid (HC1) are produced during a launch. The Corrosion Laboratory at NASA/KSC was established in 1985 to conduct electrochemical studies of corrosion on materials and coatings under conditions similar to those encountered at the launch pads. I will present highlights of some of these investigations.

  14. Farming of Vegetables in Space-Limited Environments

    NASA Astrophysics Data System (ADS)

    He, Jie

    2015-10-01

    Vegetables that contain most of the essential components of human nutrition are perishable and cannot be stocked. To secure vegetable supply in space limited cities such as Singapore, there are different farming methods to produce vegetables. These include low-cost urban community gardening and innovative rooftop and vertical farms integrated with various technologies such as hydroponics, aquaponics and aeroponics. However, for large-scale vegetable production in space-limited Singapore, we need to develop farming systems that not only increase productivity many-fold per unit of land but also produce all types of vegetable, all year-round for today and the future. This could be resolved through integrated vertical aeroponic farming system. Manipulation of root-zone (RZ) environments such as cooling the RZ, modifying mineral nutrients and introducing elevated RZ CO2 using aeroponics can further boost crop productivity beyond what can be achieved from more efficient use of land area. We could also adopt energy saving light emitting diodes (LEDs) for vertical aeroponic farming system to promote uniform growth and to improve the utilisation of limited space via shortening the growth cycle, thus improving vegetable production in a cost-effective manner.

  15. Experimental Studies of NAK in a Simulated Space Environment

    NASA Astrophysics Data System (ADS)

    Gibson, M. A.; Sanzi, J.; Ljubanovic, D.

    Space fission power systems are being developed at the National Aeronautics and Space Administration (NASA) and Department of Energy (DOE) with a short term goal of building a full scale, non-nuclear, Technology Demonstration Unit (TDU) test at NASA's Glenn Research Center. Due to the geometric constraints, mass restrictions, and fairly high tempera- tures associated with space reactors, liquid metals are typically used as the primary coolant. A eutectic mixture of sodium (22 percent) and potassium (78 percent), or NaK, has been chosen as the coolant for the TDU with a total system capacity of approximately 55L. NaK, like all alkali metals, is very reactive, and warrants certain safety considerations. To adequately examine the risk associated with the personnel, facility, and test hardware during a potential NaK leak in the large scale TDU test, a small scale experiment was performed in which NaK was released in a thermal vacuum chamber under controlled conditions. The study focused on detecting NaK leaks in the vacuum environment as well as the molecular flow of the NaK vapor. This paper reflects the work completed during the NaK experiment and provides results and discussion relative to the findings.

  16. Characteristics of Elastomer Seals Exposed to Space Environments

    NASA Technical Reports Server (NTRS)

    Daniels, Christopher C.; deGroh, Henry, III; Dunlap, Patrick H., Jr.; Finkbeiner, Joshua R.; Steinetz, Bruce M.; Bastrzyk, Marta B.; Oswald, Jay J.; Banks, Bruce A.; Dever, Joyce A.; Miller, Sharon K.; Waters, Deborah L.

    2008-01-01

    A universal docking and berthing system is being developed by the National Aeronautics and Space Administration (NASA) to support all future space exploration missions to low-Earth orbit (LEO), to the Moon, and to Mars. The Low Impact Docking System (LIDS) is being designed to operate using a seal-on-seal configuration in numerous space environments, each having unique exposures to temperature, solar radiation, reactive elements, debris, and mission duration. As the LIDS seal is likely to be manufactured from an elastomeric material, performance evaluation of elastomers after exposure to atomic oxygen (AO) and ultraviolet radiation (UV) was conducted, of which the work presented herein was a part. Each of the three candidate silicone elastomer compounds investigated, including Esterline ELA-SA-401, and Parker Hannifin S0383-70 and S0899-50, was characterized as a low outgassing compound, per ASTM E595, having percent total mass loss (TML) less than 1.0 percent and collected volatile condensable materials (CVCM) less than 0.1 percent. Each compound was compatible with the LIDS operating environment of -50 to 50 C. The seal characteristics presented include compression set, elastomer-to-elastomer adhesion, and o-ring leakage rate. The ELA-SA-401 compound had the lowest variation in compression set with temperature. The S0383-70 compound exhibited the lowest compression set after exposure to AO and UV. The adhesion for all of the compounds was significantly reduced after exposure to AO and was further decreased after exposure to AO and UV. The leakage rates of o-ring specimens showed modest increases after exposure to AO. The leakage rates after exposure to AO and UV were increased by factors of up to 600 when compared to specimens in the as-received condition.

  17. Carrier Plus: A Sensor Payload for Living With a Star Space Environment Testbed (LWS/SET)

    NASA Technical Reports Server (NTRS)

    Marshall, Cheryl; Moss, Steven; Howard, Regan; LaBel, Kenneth; Grycewicz, Tom; Barth, Janet; Brewer, Dana

    2003-01-01

    The paper discusses the following: 1. Living with a Star (LWS) program: space environment testbed (SET); natural space environment. 2. Carrier plus: goals and benefits. 3. ON-orbit sensor measurements. 4. Carrier plus architecture. 5. Participation in carrier plus.

  18. The energy spectrum of Jovian electrons in interplanetary space

    NASA Astrophysics Data System (ADS)

    Christon, S. P.; Cummings, A. C.; Stone, E. C.; Webber, W. R.

    1985-08-01

    The energy spectrum of electrons with energies approx 10 to approx 180 MeV measured with the electron telescope on the Voyager 1 and 2 spacecraft in interplanetary space from 1978 to 1983 is studied. The kinetic energy of electrons is determined by double dE/dx measurements from the first two detectors (D1, D2) of a stack of eight solid state detectors and by the range of particle penetration into the remaining six detectors (D3 to D8) which are interleaved with tungsten absorbers. From 1978 to 1983 (radial range approx 2 to approx 12 AU) electrons of Jovian origin were clearly observable for electrons stopping in D3(e or MeV) and in D4 (E or = 8 MeV). . For electrons stopping in D5 (E or = 12 MeV), the jovian flux dominated the galactic electron flux for a period of approximately one year near the encounter with Jupiter. Jovian electrons were also observed in D6(E or = 21 Mev) 1 MeV but not in D7(E 28 MeV). A detailed interpretation of the electron variations in all energy channels depends on an accurate subtraction of background induced by energetic protons of a few 100 MeV. This substraction is facilitated by laboratory calibration results at several energies. Further results on the differential energy spectrum of Jovian electrons and limits on the maximum detected energies will be reported.

  19. The energy spectrum of Jovian electrons in interplanetary space

    NASA Technical Reports Server (NTRS)

    Christon, S. P.; Cummings, A. C.; Stone, E. C.; Webber, W. R.

    1985-01-01

    The energy spectrum of electrons with energies approximately 10 to approximately 180 MeV measured with the electron telescope on the Voyager 1 and 2 spacecraft in interplanetary space from 1978 to 1983 is reported. The kinetic energy of electrons is determined by double dE/dx measurements from the first two detectors (D1,D2) of a stack of eight solid state detectors and by the range of particle penetration into the remaining six detectors (D3 to D8) which are interleaved with tungsten absorbers.

  20. Spectral differences in real-space electronic structure calculations

    NASA Astrophysics Data System (ADS)

    Jordan, D. K.; Mazziotti, D. A.

    2004-01-01

    Real-space grids for electronic structure calculations are efficient because the potential is diagonal while the second derivative in the kinetic energy may be sparsely evaluated with finite differences or finite elements. In applications to vibrational problems in chemical physics a family of methods known as spectral differences has improved finite differences by several orders of magnitude. In this paper the use of spectral differences for electronic structure is studied. Spectral differences are implemented in two electronic structure programs PARSEC and HARES which currently employ finite differences. Applications to silicon clusters and lattices indicate that spectral differences achieve the same accuracy as finite differences with less computational work.

  1. High-performing simulations of the space radiation environment for the International Space Station and Apollo Missions

    NASA Astrophysics Data System (ADS)

    Lund, Matthew Lawrence

    The space radiation environment is a significant challenge to future manned and unmanned space travels. Future missions will rely more on accurate simulations of radiation transport in space through spacecraft to predict astronaut dose and energy deposition within spacecraft electronics. The International Space Station provides long-term measurements of the radiation environment in Low Earth Orbit (LEO); however, only the Apollo missions provided dosimetry data beyond LEO. Thus dosimetry analysis for deep space missions is poorly supported with currently available data, and there is a need to develop dosimetry-predicting models for extended deep space missions. GEANT4, a Monte Carlo Method, provides a powerful toolkit in C++ for simulation of radiation transport in arbitrary media, thus including the spacecraft and space travels. The newest version of GEANT4 supports multithreading and MPI, resulting in faster distributive processing of simulations in high-performance computing clusters. This thesis introduces a new application based on GEANT4 that greatly reduces computational time using Kingspeak and Ember computational clusters at the Center for High Performance Computing (CHPC) to simulate radiation transport through full spacecraft geometry, reducing simulation time to hours instead of weeks without post simulation processing. Additionally, this thesis introduces a new set of detectors besides the historically used International Commission of Radiation Units (ICRU) spheres for calculating dose distribution, including a Thermoluminescent Detector (TLD), Tissue Equivalent Proportional Counter (TEPC), and human phantom combined with a series of new primitive scorers in GEANT4 to calculate dose equivalence based on the International Commission of Radiation Protection (ICRP) standards. The developed models in this thesis predict dose depositions in the International Space Station and during the Apollo missions showing good agreement with experimental measurements

  2. Current understanding and issues on electron beam injection in space

    NASA Technical Reports Server (NTRS)

    Papadopoulos, K.; Szuszczewicz, E. P.

    1988-01-01

    The status of the physics understanding involved in electron beam injection in space is reviewed. The paper examines our understanding of beam plasma interactions and their associated wave and energized particle spectra of the processes involved in the beam plasma discharge, and of the vehicle charge neutralization. 'Strawman' models are presented for comparison with experimental observations.

  3. Space Environment NanoSat Experiment (SENSE) - A New Frontier in Operational Space Environmental Monitoring (Invited)

    NASA Astrophysics Data System (ADS)

    Kalamaroff, K. I.; Thompson, D. C.; Cooke, D. L.; Gentile, L. C.; Bonito, N. A.; La Tour, P.; Sondecker, G.; Bishop, R. L.; Nicholas, A. C.; Doe, R. A.

    2013-12-01

    The Space Environmental NanoSat Experiment (SENSE) program is a rapid development effort of the USAF Space and Missiles Center Development Planning Directorate (SMC/XR) which will demonstrate the capability of NanoSats to perform space missions in an affordable and resilient manner. The three primary objectives for the SENSE mission are: 1) to develop best practices for operational CubeSat/NanoSat procurement, development, test, and operations; 2) to mature CubeSat bus and sensor component technology readiness levels; and 3) to demonstrate the operational utility of CubeSat measurements by flowing validated, low-latency data into operational space weather models. SENSE consists of two 3-U CubeSats built by Boeing Phantom Works. Both satellites are 3-axis stabilized with star cameras for attitude determination and are equipped with a Compact Total Electron Density Sensor (CTECS) to provide radio occultation measurements of total electron content and L-band scintillation. One satellite has a Cubesat Tiny Ionospheric Photometer (CTIP) monitoring 135.6 nm photons produced by the recombination of O+ ions and electrons. The other satellite has a Wind Ion Neutral Composite Suite (WINCS) to acquire simultaneous co-located, in situ measurements of atmospheric and ionospheric density, composition, temperature and winds/drifts. Mission data will be used to improve current and future space weather models and demonstrate the utility of data from CubeSats for operational weather requirements. Launch is scheduled for November 2013, and we will discuss the first 30 days of on-orbit operations.

  4. Prototype software reuse environment at Goddard Space Flight Center

    NASA Technical Reports Server (NTRS)

    Truszkowski, Walt

    1989-01-01

    The Goddard Space Flight Center (GSFC) work is organized into four phases and includes participation by a contractor, CTA, Inc. The first phase was an automation study, which began with a comprehensive survey of software development automation technologies. Eight technical areas were analyzed for goals, current capabilities, and obstacles. The study documented current software development practice in GSFC Mission Operations and Data Systems Directorate, and presented short- and long-term recommendations that included focus on reuse and object-oriented development. The second phase, which has been completed, developed a prototype reuse environment with tools supporting object-oriented requirements analysis and design. This phase addressed the operational concept of software reuse, i.e., it attempted to understand how software can be reused. This environment has two semantic networks: object and keywords, and includes automated search, interactive browsing and a graphical display of database contents. Phase 3 was a domain analysis of Payload Operations Control Center (POCC) software. The goal in this phase was to create an initial repository of reusable components and techniques. Seven existing Operations Control Centers at GSFC were studied, but the domain analysis proved to be very slow. A lesson learned from this was that senior people who understand the environment and the functionality of the area are needed to perform successful domain analyses.

  5. Protection from Induced Space Environments Effects on the International Space Station

    NASA Technical Reports Server (NTRS)

    Soares, Carlos; Mikatarian, Ron; Stegall, Courtney; Schmidl, Danny; Huang, Alvin; Olsen, Randy; Koontz, Steven

    2010-01-01

    The International Space Station (ISS) is one of the largest, most complex multinational scientific projects in history and protection from induced space environments effects is critical to its long duration mission as well as to the health of the vehicle and safety of on-orbit operations. This paper discusses some of the unique challenges that were encountered during the design, assembly and operation of the ISS and how they were resolved. Examples are provided to illustrate the issues and the risk mitigation strategies that were developed to resolve these issues. Of particular importance are issues related with the interaction of multiple spacecraft as in the case of ISS and Visiting Vehicles transporting crew, hardware elements, cargo and scientific payloads. These strategies are applicable to the development of future long duration space systems, not only during design, but also during assembly and operation of these systems.

  6. Stimulated coherent emission from short electron bunches in free space

    SciTech Connect

    Robb, G.R.M.; Phelps, A.D.R.; Ginzburg, N.S.

    1995-12-31

    In previous papers stimulated coherent emission of short electron bunches (superradiance-SR) was considered in the frame of 1-D models. In the present work we study superradiance of an electron bunch which has a finite transverse size in the frame of a 2-D model. This model include effects of optical guiding as well as transverse electromagnetic energy escaping and diffraction. Using a nonstationary parabolic equation we described SR of a sheet shaped electron bunch in free space. It is shown that the radiation is composed of a sequence of e.m. pulses which are diffracted after escaping from the channel formed by the electron beam. This process is accompanied by a progressive increase of the electron efficiency. This enhancement is caused by the phenomenon of permanent self supporting resonance due to the variation of the radiation angle and frequency.

  7. Space charge effects in ultrafast electron diffraction and imaging

    SciTech Connect

    Tao Zhensheng; Zhang He; Duxbury, P. M.; Berz, Martin; Ruan, Chong-Yu

    2012-02-15

    Understanding space charge effects is central for the development of high-brightness ultrafast electron diffraction and microscopy techniques for imaging material transformation with atomic scale detail at the fs to ps timescales. We present methods and results for direct ultrafast photoelectron beam characterization employing a shadow projection imaging technique to investigate the generation of ultrafast, non-uniform, intense photoelectron pulses in a dc photo-gun geometry. Combined with N-particle simulations and an analytical Gaussian model, we elucidate three essential space-charge-led features: the pulse lengthening following a power-law scaling, the broadening of the initial energy distribution, and the virtual cathode threshold. The impacts of these space charge effects on the performance of the next generation high-brightness ultrafast electron diffraction and imaging systems are evaluated.

  8. Hilbert space renormalization for the many-electron problem

    NASA Astrophysics Data System (ADS)

    Li, Zhendong; Chan, Garnet Kin-Lic

    2016-02-01

    Renormalization is a powerful concept in the many-body problem. Inspired by the highly successful density matrix renormalization group (DMRG) algorithm, and the quantum chemical graphical representation of configuration space, we introduce a new theoretical tool: Hilbert space renormalization, to describe many-electron correlations. While in DMRG, the many-body states in nested Fock subspaces are successively renormalized, in Hilbert space renormalization, many-body states in nested Hilbert subspaces undergo renormalization. This provides a new way to classify and combine configurations. The underlying wavefunction Ansatz, namely, the Hilbert space matrix product state (HS-MPS), has a very rich and flexible mathematical structure. It provides low-rank tensor approximations to any configuration interaction (CI) space through restricting either the "physical indices" or the coupling rules in the HS-MPS. Alternatively, simply truncating the "virtual dimension" of the HS-MPS leads to a family of size-extensive wave function Ansätze that can be used efficiently in variational calculations. We make formal and numerical comparisons between the HS-MPS, the traditional Fock-space MPS used in DMRG, and traditional CI approximations. The analysis and results shed light on fundamental aspects of the efficient representation of many-electron wavefunctions through the renormalization of many-body states.

  9. Opportunities for electron microscopy in space radiation biology

    SciTech Connect

    Lett, J.T.

    1986-01-01

    Densely ionizing, particulate radiations in outer space are likely to cause to mammalian tissues biological damage that is particularly amenable to examination by the techniques of electron microscopy. This situation arises primarily from the fact that once the density of ionization along the particle track exceeds a certain value, small discrete lesions involving many adjacent cells may be caused in organized tissues. Tissue damage produced by ionization densities below the critical value also afford opportunities for electron microscopic evaluation, as is shown by the damage produced in optic and proximate tissues of the New Zealand white rabbit in terrestrial experiments. Late radiation sequelae in nondividing, or terminally differentiating, tissues, and in stem cell populations, are of special importance in these regards. It is probable that evaluations of the hazards posed to astronauts by galactic particulate radiations during prolonged missions in outer space will not be complete without adequate electron microscopic evaluation of the damage those radiations cause to organized tissues.

  10. Development of a novel electron source for active space experiments

    NASA Astrophysics Data System (ADS)

    Everding, Daniel

    2013-01-01

    Recent advances in light emitting diode (LED) technology have facilitated a potential remedy to the problems plaguing filament based electron sources. Using spaceworthy LEDs, the photoelectron cathode and its progenitor the ultraviolet cathode (UVC) take advantage of the photoelectric effect to produce electrons for space based experiments. To produce these devices, two species of LED, each producing either ultraviolet or visible radiation, were collected and tested to determine potential photocurrent output. Additionally, materials with requisite photoemission characteristics were collected and tested in vacuum with the LEDs to assess their usefulness as photoelectron sources. Furthermore, circuitry and computer software was compiled, tested, and refined to control the experimental and custodial duties of the UVC and photoelectron cathode while deployed as an electron source in space.

  11. Coherence of k-space electrons: application to TDS electrons by DBI.

    PubMed

    Herring, Rodney A

    2013-06-01

    Methods of controlled electron interference in k-space on the diffraction plane by means of an electron biprism invented during the Tonomura Electron Wavefront Project are briefly reviewed. The results presented show the partial coherence of self-interfered diffusely scattered electrons, elastically scattered and inelastically scattered, found outside and in between the Bragg diffracted beams often referred to as thermal diffuse scattering (TDS) of electrons. The interference fringes formed in the TDS intensity have been used to calculate a mean displacement of the atom of u ≈ 12 pm in Aluminum in the direction perpendicular to the Bragg planes. PMID:23536697

  12. James Webb Space Telescope Mid Infra-Red Instrument Pulse-Tube Cryocooler Electronics

    NASA Technical Reports Server (NTRS)

    Harvey, D.; Flowers, T.; Liu, N.; Moore, K.; Tran, D.; Valenzuela, P.; Franklin, B.; Michaels, D.

    2013-01-01

    The latest generation of long life, space pulse-tube cryocoolers require electronics capable of controlling self-induced vibration down to a fraction of a newton and coldhead temperature with high accuracy down to a few kelvin. Other functions include engineering diagnostics, heater and valve control, telemetry and safety protection of the cryocooler subsystem against extreme environments and operational anomalies. The electronics are designed to survive the thermal, vibration, shock and radiation environment of launch and orbit, while providing a design life in excess of 10 years on-orbit. A number of our current generation high reliability radiation-hardened electronics units are in various stages of integration on several space flight payloads. This paper describes the features and performance of our latest flight electronics designed for the pulse-tube cryocooler that is the pre-cooler for a closed cycle Joule-Thomson cooler providing 6K cooling for the James Webb Space Telescope (JWST) Mid Infra-Red Instrument (MIRI). The electronics is capable of highly accurate temperature control over the temperature range from 4K to 15K. Self-induced vibration is controlled to low levels on all harmonics up to the 16th. A unique active power filter controls peak-to-peak reflected ripple current on the primary power bus to a very low level. The 9 kg unit is capable of delivering 360W continuous power to NGAS's 3-stage pulse-tube High-Capacity Cryocooler (HCC).

  13. Alteration of amino acids and related compounds in space environments

    NASA Astrophysics Data System (ADS)

    Kobayashi, K.; Tsuboi, T.; Kaneko, T.; Takano, Y.; Hashimoto, H.; Haruyama, J.; Yamashita, M.

    Organic compounds have been found in carbonaceous chondrites and in comets, which were possible materials for the first life on the Earth. It is suggested that these organics were originally formed in ice mantles of interstellar dusts (ISD) in molecular cloud. A number of studies were done to simulate reactions in ISD: Formation of amino acid precursors was reported when simulated interstellar media was irradiated with protons [1] or UV [2]. Extraterrestrial amino acids or their precursors in interstellar space, comets or meteorites were exposed to cosmic rays and UV before they were delivered to planets. Here we investigated stability of amino acids and related compounds in interstellar, lunar and planetary environments. Target compounds are (i) free amino acids, (ii) human serum albumin (HSA) and (iii) "possible interstellar complex organics (PICO)", which were formed from a mixture of carbon monoxide, ammonia and water by proton irradiation. Aqueous solutions of the target compounds were irradiated with gamma rays at room temperature, and they were acid-hydrolyzed before amino acid analysis. Recovery ratio of amino acids in HSA and PICO was much more than that of free amino acids. Samples mixed with basalt powder were more stable than those without the regolith. When the targets were irradiated after freeze-dried, their decomposition was not observed up to 30 kGy dosage. The present results show that extraterrestrial amino acids are quite stable if they are present as complex precursors in mineral matrix. Organic compounds in ISD are exposed not only to cosmic rays but also UV photons. It would be of interest to test stability of organic compounds in actual space environments: The exposure facility of International Space Station would be the place where the target molecules can be irradiated with cosmic rays and solar UV (including extreme UV) at the same time. [1] Kobayashi et al., Adv. Space Res., 16, 21 (1995), Kasamatsu et al., Bull. Chem. Soc. Jpn., 70

  14. Diverse Electron-Induced Optical Emissions from Space Observatory Materials at Low Temperatures

    NASA Technical Reports Server (NTRS)

    Dennison, J.R.; Jensen, Amberly Evans; Wilson, Gregory; Dekany, Justin; Bowers, Charles W.; Meloy, Robert

    2013-01-01

    Electron irradiation experiments have investigated the diverse electron-induced optical and electrical signatures observed in ground-based tests of various space observatory materials at low temperature. Three types of light emission were observed: (i); long-duration cathodoluminescence which persisted as long as the electron beam was on (ii) short-duration (<1 s) arcing, resulting from electrostatic discharge; and (iii) intermediate-duration (100 s) glow-termed "flares". We discuss how the electron currents and arcing-as well as light emission absolute intensity and frequency-depend on electron beam energy, power, and flux and the temperature and thickness of different bulk (polyimides, epoxy resins, and silica glasses) and composite dielectric materials (disordered SiO2 thin films, carbon- and fiberglass-epoxy composites, and macroscopically-conductive carbon-loaded polyimides). We conclude that electron-induced optical emissions resulting from interactions between observatory materials and the space environment electron flux can, in specific circumstances, make significant contributions to the stray light background that could possibly adversely affect the performance of space-based observatories.

  15. Dust in Interplanetary Space and in the Local Galactic Environment

    NASA Astrophysics Data System (ADS)

    Grün, E.; Dikarev, V.; Frisch, P. C.; Graps, A.; Kempf, S.; Krüger, H.; Landgraf, M.; Moragas-Klostermeyer, G.; Srama, R.

    2004-05-01

    The solar system is a natural laboratory, accessible by a variety of methods, for studying the astrophysics of dust. Astronomical measurements mostly at visible and infrared wavelengths, yield the large-scale distribution of dust and its average composition. Examining natural surfaces deployed to the space environment, and assessing those surfaces' micro-crater distributions, reveals the size distribution of dust. Meteor observations and their corresponding measurements provide orbital information of dust grains and their genetic interrelation to the larger bodies in our solar system: comets and asteroids. From analyses of meteorites and interplanetary dust particles collected in the stratosphere, we have a comprehensive understanding of the isotopic, elemental, and mineralogical composition of this primordial material. Finally, in situ dust analysis via dust detectors located in interplanetary space, the most versatile method, have been providing data to determine the dust particles' mass, speed, trajectory, and chemical composition. An assortment of dust exhibiting a variety of dynamical processes has been identified in interplanetary space. In Jupiter's proximity, intense streams have been observed of nanometer-sized ash particles, which are emitted from the volcanoes of Jupiter's moon Io. These particles are accelerated by the powerful Jovian magnetic field to speeds of several 100 km/s, and are propelled further into interplanetary and interstellar space by the solar wind magnetic field. In interplanetary space, concentrations of collisional debris in the asteroid belt have been identified by infrared observations. The Poynting-Robertson effect drags these particles in towards the Earth and the Sun, where they sublimate. If the giant planets did not block their inward drift, a similar fate is expected for the dust assortment that is generated by collisions in the Kuiper belt. Another dust population is the mostly sub-micron-sized dust from comets, released

  16. Space shuttle electromagnetic environment experiment. Phase A: Definition study

    NASA Technical Reports Server (NTRS)

    Haber, F.; Showers, R. M.; Kocher, C.; Forrest, L. A., Jr.

    1976-01-01

    Methods for carrying out measurements of earth electromagnetic environment using the space shuttle as a measurement system platform are herein reported. The goal is to provide means for mapping intentional and nonintentional emitters on earth in the frequency range 0.4 to 40 GHz. A survey was made of known emitters using available data from national and international regulatory agencies, and from industry sources. The spatial distribution of sources, power levels, frequencies, degree of frequency re-use, etc., found in the survey, are here presented. A concept is developed for scanning the earth using a directive antenna whose beam is made to rotate at a fixed angle relative to the nadir; the illuminated area swept by the beam is of the form of cycloidal annulus over a sphere. During the beam's sojourn over a point, the receiver sweeps in frequency over ranges in the order of octave width using sweeping filter bandwidths sufficient to give stable readings.

  17. Seals Having Textured Portions for Protection in Space Environments

    NASA Technical Reports Server (NTRS)

    Daniels, Christopher (Inventor); Garafolo, Nicholas (Inventor)

    2016-01-01

    A sealing construct for a space environment includes a seal-bearing object, a seal on the seal-bearing object, and a seal-engaging object. The seal includes a seal body having a sealing surface, and a textured pattern at the sealing surface, the textured pattern defining at least one shaded channel surface. The seal-engaging object is selectively engaged with the seal-bearing object through the seal. The seal-engaging object has a sealing surface, wherein, when the seal-engaging object is selectively engaged with the seal-bearing object, the sealing surface of the seal-engaging object engages the sealing surface of the seal, and the seal is compressed between the seal-bearing object and the seal-engaging object such that at least one shaded channel surface engages the sealing surface of the seal-engaging object.

  18. Space shuttle electromagnetic environment experiment. Phase A: Definition study

    NASA Technical Reports Server (NTRS)

    Haber, F.; Showers, R. M.; Taheri, S. H.; Forrest, L. A., Jr.; Kocher, C.

    1974-01-01

    A program is discussed which develops a concept for measuring the electromagnetic environment on earth with equipment on board an orbiting space shuttle. Earlier work on spaceborne measuring experiments is reviewed, and emissions to be expected are estimated using, in part, previously gathered data. General relations among system parameters are presented, followed by a proposal on spatial and frequency scanning concepts. The methods proposed include a nadir looking measurement with small lateral scan and a circularly scanned measurement looking tangent to the earth's surface at the horizon. Antenna requirements are given, assuming frequency coverage from 400 MHz to 40 GHz. For the low frequency range, 400-1000 MHz, a processed, thinned array is proposed which will be more fully analyzed in the next phase of the program. Preliminary hardware and data processing requirements are presented.

  19. Atmospheric environment for space shuttle (STS-33) launch

    NASA Technical Reports Server (NTRS)

    Jasper, G. L.; Batts, G. W.

    1990-01-01

    A summary is presented of selected atmospheric conditions observed near space shuttle STS-33 at launch time. STS-33 carried a DOD payload and the flight azimuth is denoted by a reference flight azimuth, since the actual flight azimuth is not known. Values of ambient pressure, temperature, moisture, ground winds, visual observations (clouds), and winds aloft are included. The sequence of pre-launch Jimsphere measured vertical wind profiles is given. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-33 vehicle ascent, was constructed. The STS-33 ascent atmospheric data tape was constructed by NASA-Marshall to provide an internally consistent data set for use in postflight performance assessments and represents the best estimates of the launch environment to the 400,000 ft altitude that was traversed by the STS-33 vehicle.

  20. Atmospheric environment for Space Shuttle Columbia (STS-40) launch

    NASA Technical Reports Server (NTRS)

    Jasper, G. L.; Batts, G. W.

    1992-01-01

    A summary of selected atmospheric conditions observed near the Space Shuttle Columbia (STS-40) launch time on 5 Jun. 1991, at KSC is presented. Values of ambient pressure, temperature, moisture, ground winds, visual observation (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere-measured vertical wind profiles is given. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-40 vehicle ascent was constructed. The STS-40 ascent atmospheric data tape was constructed by MSFC's Earth Science and Applications Division to provide an internally consistent data set for use in postflight performance assessments and represents the best estimate of the launch environment to the 400,000-ft altitude that was traversed by the STS-40 vehicle.

  1. Natural environment support guidelines for space shuttle tests and operations

    NASA Technical Reports Server (NTRS)

    Carter, E. A.; Brown, S. C.

    1974-01-01

    All space shuttle events from launch through solid rocket booster recovery and orbiter landing are considered in terms of constraints placed on those operations by the natural environment. Thunderstorm activity is discussed as an example of a possible hazard. The activities most likely to require advanced detection and monitoring techniques are identified as those from deorbit decision to Orbiter landing. The inflexible flight plan will require the transmission of real time wind profile information below 24 km and warnings of thunderstorms or turbulence in the Orbiter flight path. Extensive aerial reconnaissance and communication facilities and procedures to permit immediate transmission of aircraft reports to the mission control authority and to the Orbiter will also be required.

  2. Electrical behaviour of a silicone elastomer under simulated space environment

    NASA Astrophysics Data System (ADS)

    Roggero, A.; Dantras, E.; Paulmier, T.; Tonon, C.; Balcon, N.; Rejsek-Riba, V.; Dagras, S.; Payan, D.

    2015-04-01

    The electrical behavior of a space-used silicone elastomer was characterized using surface potential decay and dynamic dielectric spectroscopy techniques. In both cases, the dielectric manifestation of the glass transition (dipole orientation) and a charge transport phenomenon were observed. An unexpected linear increase of the surface potential with temperature was observed around Tg in thermally-stimulated potential decay experiments, due to molecular mobility limiting dipolar orientation in one hand, and 3D thermal expansion reducing the materials capacitance in the other hand. At higher temperatures, the charge transport process, believed to be thermally activated electron hopping with an activation energy of about 0.4 eV, was studied with and without the silica and iron oxide fillers present in the commercial material. These fillers were found to play a preponderant role in the low-frequency electrical conductivity of this silicone elastomer, probably through a Maxwell-Wagner-Sillars relaxation phenomenon.

  3. Radiation environment at aviation altitudes and in space.

    PubMed

    Sihver, L; Ploc, O; Puchalska, M; Ambrožová, I; Kubančák, J; Kyselová, D; Shurshakov, V

    2015-06-01

    On the Earth, protection from cosmic radiation is provided by the magnetosphere and the atmosphere, but the radiation exposure increases with increasing altitude. Aircrew and especially space crew members are therefore exposed to an increased level of ionising radiation. Dosimetry onboard aircraft and spacecraft is however complicated by the presence of neutrons and high linear energy transfer particles. Film and thermoluminescent dosimeters, routinely used for ground-based personnel, do not reliably cover the range of particle types and energies found in cosmic radiation. Further, the radiation field onboard aircraft and spacecraft is not constant; its intensity and composition change mainly with altitude, geomagnetic position and solar activity (marginally also with the aircraft/spacecraft type, number of people aboard, amount of fuel etc.). The European Union Council directive 96/29/Euroatom of 1996 specifies that aircrews that could receive dose of >1 mSv y(-1) must be evaluated. The dose evaluation is routinely performed by computer programs, e.g. CARI-6, EPCARD, SIEVERT, PCAire, JISCARD and AVIDOS. Such calculations should however be carefully verified and validated. Measurements of the radiation field in aircraft are thus of a great importance. A promising option is the long-term deployment of active detectors, e.g. silicon spectrometer Liulin, TEPC Hawk and pixel detector Timepix. Outside the Earth's protective atmosphere and magnetosphere, the environment is much harsher than at aviation altitudes. In addition to the exposure to high energetic ionising cosmic radiation, there are microgravity, lack of atmosphere, psychological and psychosocial components etc. The milieu is therefore very unfriendly for any living organism. In case of solar flares, exposures of spacecraft crews may even be lethal. In this paper, long-term measurements of the radiation environment onboard Czech aircraft performed with the Liulin since 2001, as well as measurements and

  4. The International Space Station and the Space Debris Environment: 10 Years On

    NASA Technical Reports Server (NTRS)

    Johnson, Nicholas; Klinkrad, Heiner

    2009-01-01

    For just over a decade the International Space Station (ISS), the most heavily protected vehicle in Earth orbit, has weathered the space debris environment well. Numerous hypervelocity impact features on the surface of ISS caused by small orbital debris and meteoroids have been observed. In addition to typical impacts seen on the large solar arrays, craters have been discovered on windows, hand rails, thermal blankets, radiators, and even a visiting logistics module. None of these impacts have resulted in any degradation of the operation or mission of the ISS. Validating the rate of small particle impacts on the ISS as predicted by space debris environment models is extremely complex. First, the ISS has been an evolving structure, from its original 20 metric tons to nearly 300 metric tons (excluding logistics vehicles) ten years later. Hence, the anticipated space debris impact rate has grown with the increasing size of ISS. Secondly, a comprehensive visual or photographic examination of the complete exterior of ISS has never been accomplished. In fact, most impact features have been discovered serendipitously. Further complications include the estimation of the size of an impacting particle without knowing its mass, velocity, and angle of impact and the effect of shadowing by some ISS components. Inadvertently and deliberately, the ISS has also been the source of space debris. The U.S. Space Surveillance Network officially cataloged 65 debris from ISS from November 1998 to November 2008: from lost cameras, sockets, and tool bags to intentionally discarded equipment and an old space suit. Fortunately, the majority of these objects fall back to Earth quickly with an average orbital lifetime of less than two months and a maximum orbital lifetime of a little more than 15 months. The cumulative total number of debris object-years is almost exactly 10, the equivalent of one piece of debris remaining in orbit for 10 years. An unknown number of debris too small to be

  5. Thermal System Upgrade of the Space Environment Simulation Test Chamber

    NASA Technical Reports Server (NTRS)

    Desai, Ashok B.

    1997-01-01

    The paper deals with the refurbishing and upgrade of the thermal system for the existing thermal vacuum test facility, the Space Environment Simulator, at NASA's Goddard Space Flight Center. The chamber is the largest such facility at the center. This upgrade is the third phase of the long range upgrade of the chamber that has been underway for last few years. The first phase dealt with its vacuum system, the second phase involved the GHe subsystem. The paper describes the considerations of design philosophy options for the thermal system; approaches taken and methodology applied, in the evaluation of the remaining "life" in the chamber shrouds and related equipment by conducting special tests and studies; feasibility and extent of automation, using computer interfaces and Programmable Logic Controllers in the control system and finally, matching the old components to the new ones into an integrated, highly reliable and cost effective thermal system for the facility. This is a multi-year project just started and the paper deals mainly with the plans and approaches to implement the project successfully within schedule and costs.

  6. OverView of Space Applications for Environment (SAFE) initiative

    NASA Astrophysics Data System (ADS)

    Hamamoto, Ko; Fukuda, Toru; Tajima, Yoshimitsu; Takeuchi, Wataru; Sobue, Shinichi; Nukui, Tomoyuki

    2014-06-01

    Climate change and human activities have a direc or indirect influence on the acceleration of environmental problems and natural hazards such as forest fires, draughts and floods in the Asia-Pacific countries. Satellite technology has become one of the key information sources in assessment, monitoring and mitigation of these disasters and related phenomenon. However, there are still gaps between science and application of satellite technology in real-world usage. Asia-Pacific Regional Space Agency Forum (APRSAF) recommended to initiate the Space Applications for Environment (SAFE) proposal providing opportunity to potential user agencies in the Asia Pacific region to develop prototype applications of satellite technology for number of key issues including forest resources management, coastal monitoring and management, agriculture and food security, water resource management and development user-friendly tools for application of satellite technology. This paper describes the overview of SAFE initiative and outcomes of two selected prototypes; agricultural drought monitoring in Indonesia and coastal management in Sri Lanka, as well as the current status of on-going prototypes.

  7. Robust free-space optical communication for indoor information environment

    NASA Astrophysics Data System (ADS)

    Nakada, Toyohisa; Itoh, Hideo; Kunifuji, Susumu; Nakashima, Hideyuki

    2003-10-01

    The purpose of our study is to establish a robust communication, while keeping security and privacy, between a handheld communicator and the surrounding information environment. From the viewpoint of low power consumption, we have been developing a reflectivity modulating communication module composed of a liquid crystal light modulator and a corner-reflecting mirror sheet. We installed a corner-reflecting sheet instead of light scattering sheet in a handheld videogame machine with a display screen with a reflection-type liquid crystal. Infrared (IR) LED illuminator attached next to the IR camera of a base station illuminates all the room, and the terminal send their data to the base station by switching ON and OFF of the reflected IR beam. Intensity of reflected light differs with the position and the direction of the terminal, and sometimes the intensity of OFF signal at a certain condition is brighter than that of ON signal at another condition. To improve the communication quality, use of machine learning technique is a possibility of the solution. In this paper, we compare various machine learning techniques for the purpose of free space optical communication, and propose a new algorithm that improves the robustness of the data link. Evaluation using an actual free-space communication system is also described.

  8. Space Suit Radiator Performance in Lunar and Mars Environments

    NASA Technical Reports Server (NTRS)

    Nabity, James; Mason, Georgia; Copeland, Robert; Libberton, Kerry; Stephan, Ryan; Trevino, Luis; Paul, Heather

    2005-01-01

    During an ExtraVehicular Activity (EVA), both the heat generated by the astronaut's metabolism and that produced by the Portable Life Support System (PLSS) must be rejected to space. The heat sources include the heat of adsorption of metabolic CO2, the heat of condensation of water, the heat removed from the body by the liquid cooling garment and the load from the electrical components. Although the sublimator hardware to reject this load weighs only 1.58 kg (3.48 lbm), an additional 3.6 kg (8 lbm) of water are loaded into the unit, most of which is sublimated and lost to thus become the single largest expendable during an eight hour EVA. We can significantly reduce the amount of expendable water consumed in the sublimator by using a radiator to reject heat from the Astronaut during an EVA. Last year we reported on the design and initial operational assessment tests of our novel radiator designated the Radiator And Freeze Tolerant heat eXchanger (RAFT-X). Herein, we report on tests conducted in the NASA Johnson Space Center Chamber E Thermal Vacuum Test Facility. Up to 260 W (900 Btu/h) of heat were rejected in Lunar and Mars environments with temperatures as cold as -170 C (- 275 F). Further, the RAFT-X endured several freeze / thaw cycles and in fact, the heat exchanger was completely frozen three times without any apparent damage to the unit.

  9. Investigation of expert system design approaches for electronic design environments

    NASA Astrophysics Data System (ADS)

    Poppens, Susan A.

    1987-12-01

    Various schemes were investigated that are available for the design effort of electronic systems. The information is to be incorporated into a knowledge base to determine approaches for a particular design. Various design methodologies are to be investigated for their appropriateness and application in the aforesaid design environment. The second phase is to focus on the knowledge base gathered in the design effort for electronic design. This knowledge base is to be incorporated into a rule based expert system which can be utilized by the design engineer in the design/development of functional specifications.

  10. Free electron lasers for transmission of energy in space

    NASA Technical Reports Server (NTRS)

    Segall, S. B.; Hiddleston, H. R.; Catella, G. C.

    1981-01-01

    A one-dimensional resonant-particle model of a free electron laser (FEL) is used to calculate laser gain and conversion efficiency of electron energy to photon energy. The optical beam profile for a resonant optical cavity is included in the model as an axial variation of laser intensity. The electron beam profile is matched to the optical beam profile and modeled as an axial variation of current density. Effective energy spread due to beam emittance is included. Accelerators appropriate for a space-based FEL oscillator are reviewed. Constraints on the concentric optical resonator and on systems required for space operation are described. An example is given of a space-based FEL that would produce 1.7 MW of average output power at 0.5 micrometer wavelength with over 50% conversion efficiency of electrical energy to laser energy. It would utilize a 10 m-long amplifier centered in a 200 m-long optical cavity. A 3-amp, 65 meV electrostatic accelerator would provide the electron beam and recover the beam after it passes through the amplifier. Three to five shuttle flights would be needed to place the laser in orbit.

  11. AF-GEOSpace Version 2.5: Space Environment Software

    NASA Astrophysics Data System (ADS)

    Hilmer, R. V.; Hall, T.; Roth, C.; Ling, A.; Ginet, G. P.; Madden, D.

    2010-12-01

    AF-GEOSpace is a graphics-intensive software program with space environment models and applications developed by the Space Weather Center of Excellence at AFRL. The software addresses a wide range of physical domains, e.g., solar disturbance propagation, geomagnetic field and radiation belt configurations, auroral particle precipitation, and ionospheric scintillation. AF-GEOSpace has become a platform for developing and prototyping space weather visualization products. The new AF-GEOSpace Version 2.5 (release scheduled for 2010) expands on the content of Version 2.1 by including modules addressing the following new topics: (1) energetic proton maps for the South Atlantic Anomaly (from Ginet et al. [2007]), (2) GPS scintillation outage simulation tools, (3) magnetopause location determination (Shue et al. [1998]), (4) a plasmasphere model (Global Core Plasma Model, 2009 version based on Gallagher et al. [2000]), (5) a standard ionospheric model (International Reference Ionosphere 2007), (6) the CAMMICE/MICS model of inner magnetosphere plasma population (based on Roeder et al. [2005]), (7) magnetic field models (e.g., Tsyganenko and Sitnov [2005]), and (8) loading and displaying externally-produced 3D gridded data sets within AF-GEOSpace. Improvements to existing Version 2.1 capabilities include: (1) a 2005 update to the geomagnetic cutoff rigidity model of Smart and Shea [2003], (2) a 2005 update to the ionospheric scintillation Wide-Band Model (WBMOD) of Secan and Bussey [1994], and (3) improved magnetic field flux mapping options for the existing set of AF-GEOSpace radiation belt models. A basic review of these new AF-GEOSpace capabilities will be provided. To obtain a copy of the software, please contact the first author.

  12. Space Environment Effects: Low-Altitude Trapped Radiation Model

    NASA Technical Reports Server (NTRS)

    Huston, S. L.; Pfitzer, K. A.

    1998-01-01

    Accurate models of the Earth's trapped energetic proton environment are required for both piloted and robotic space missions. For piloted missions, the concern is mainly total dose to the astronauts, particularly in long-duration missions and during extravehicular activity (EVA). As astronomical and remote-sensing detectors become more sensitive, the proton flux can induce unwanted backgrounds in these instruments. Due to this unwanted background, the following description details the development of a new model for the low-trapped proton environment. The model is based on nearly 20 years of data from the TIRO/NOAA weather satellites. The model, which has been designated NOAAPRO (for NOAA protons), predicts the integral omnidirectional proton flux in three energy ranges: >16, >36, and >80 MeV. It contains a true solar cycle variation and accounts for the secular variation in the Earth's magnetic field. It also extends to lower values of the magnetic L parameter than does AP8. Thus, the model addresses the major shortcomings of AP8.

  13. Monitoring and Forecasting Space Weather in Geospace Environment

    NASA Technical Reports Server (NTRS)

    Lyatsky, Wladislaw; Khazanov, George V.

    2008-01-01

    For improving the reliability of Space Weather prediction, we developed a new, Polar Magnetic (PM) index of geomagnetic activity, which shows high correlation with both upstream solar wind data and related events in the magnetosphere and ionosphere. Similarly to the existing polar cap PC index, the new PM index was computed from data from two near-pole geomagnetic observatories; however, the method for computing the PM index is different. The high correlation of the PM index with both solar wind data and events in Geospace environment makes possible to improve significantly forecasting geomagnetic disturbances and such important parameters as the cross-polar-cap voltage and global Joule heating, which play an important role in the development of geomagnetic, ionospheric and thermospheric disturbances. We tested the PM index for 10-year period (1995-2004). The correlation between PM index and upstream solar wind data for these years is very high (the average correlation coefficient R approximately equal to 0.86). The PM index also shows the high correlation with the cross-polar-cap voltage and hemispheric Joule heating (the correlation coefficient between the actual and predicted values of these parameters approximately equal to 0.9), which results in significant increasing the prediction reliability of these parameters. Using the PM index of geomagnetic activity provides a significant increase in the forecasting reliability of geomagnetic disturbances and related events in Geospace environment. The PM index may be also used as an important input parameter in modeling ionospheric, magnetospheric, and thermospheric processes.

  14. Piezoelectric PVDF materials performance and operation limits in space environments.

    SciTech Connect

    Dargaville, Tim Richard; Assink, Roger Alan; Clough, Roger Lee; Celina, Mathias Christopher

    2004-11-01

    Piezoelectric polymers based on polyvinylidene fluoride (PVDF) are of interest for large aperture space-based telescopes. Dimensional adjustments of adaptive polymer films are achieved via charge deposition and require a detailed understanding of the piezoelectric material responses which are expected to suffer due to strong vacuum UV, gamma, X-ray, energetic particles and atomic oxygen under low earth orbit exposure conditions. The degradation of PVDF and its copolymers under various stress environments has been investigated. Initial radiation aging studies using gamma- and e-beam irradiation have shown complex material changes with significant crosslinking, lowered melting and Curie points (where observable), effects on crystallinity, but little influence on overall piezoelectric properties. Surprisingly, complex aging processes have also been observed in elevated temperature environments with annealing phenomena and cyclic stresses resulting in thermal depoling of domains. Overall materials performance appears to be governed by a combination of chemical and physical degradation processes. Molecular changes are primarily induced via radiative damage, and physical damage from temperature and AO exposure is evident as depoling and surface erosion. Major differences between individual copolymers have been observed providing feedback on material selection strategies.

  15. Electron density fluctuations in a disturbed ionospheric environment

    NASA Astrophysics Data System (ADS)

    Huba, J. D.; Ganguli, G.

    1988-01-01

    Electron density fluctuations in the earth's ionosphere can adversely affect SDIO systems which involve electromagnetic wave propagation, e.g., laser beams. This is particularly true for severely disturbed ionospheric conditions produced by high-altitude nuclear explosions (HANEs). This paper briefly describes, in general terms, the HANE environment and the various plasma instabilities which could generate small-scale electron density irregularities. As an example, an analysis of a single instability, the lower-hybrid-drift instability, which is likely to be excited in the ionosphere following a high altitude burst. Both the linear and nonlinear behavior of this instability are discussed. It is shown how these results can be applied to potential SDIO laser systems in a HANE environment.

  16. Optimum Electron Distributions for Space Charge Dominated Beams in Photoinjectors

    SciTech Connect

    Limborg-Deprey, C.; Bolton, P.R.; /SLAC

    2006-06-15

    The optimum photo-electron distribution from the cathode of an RF photoinjector producing a space charge dominated beam is a uniform distribution contained in an ellipsoid. For such a bunch distribution, the space charge forces are linear and the emittance growth induced by those forces is totally reversible and consequently can be compensated. With the appropriate tuning of the emittance compensation optics, the emittance, at the end of photoinjector beamline, for an ellipsoidal laser pulse, would only have two contributions, the cathode emittance and the RF emittance. For the peak currents of 50A and 100 A required from the SBand and L-Band RF gun photoinjectors discussed here, the RF emittance contribution is negligible. If such an ellipsoidal photo-electron distribution were available, the emittance at the end of the beamline could be reduced to the cathode emittance. Its value would be reduced by more than 40% from that obtained using cylindrical shape laser pulses. This potentially dramatic improvement warrants review of the challenges associated with the production of ellipsoidal photo-electrons. We assume the photo-electrons emission time to be short enough that the ellipsoidal electron pulse shape will come directly from the laser pulse. We shift the challenge to ellipsoidal laser pulse shaping. To expose limiting technical issues, we consider the generation of ellipsoidal laser pulse shape in terms of three different concepts.

  17. Polymerisation of composite materials in space environment for development of moon base

    NASA Astrophysics Data System (ADS)

    Kondyurina, I.; Kondyurin, A.; Lauke, B.

    The best way for a Moon base creation is a deployment of light construction on Moon surface after landing. The construction has to be light in deployment and hard at exploitation. A number of proposals for solidification of deployed constructions in space were presented, but the best way is a chemical reaction which leads to a formation of hard frame of space construction. A technology of large-size moon module for industrial and scientific applications is developed on the base of polymerisation technique of composite material with liquid polymer matrix. Experiments with chemical reactions of polymerisation in composite materials under high vacuum, ion beam and plasma discharge showed a possibility to use a liquid viscous polymer matrix of composite materials under space conditions without hermetic coating. Epoxy resins with thermal and photo initiation system of polymerisation were studied. The effects of initiation of the polymerisation reaction under simulated space factors were observed. The polymerised frames can be used in energetic, electronic and other industries on Moon surface. The investigations were partially supported by Alexander von Humboldt Foundation and European Space Agency, ESTEC (contract 17083/03/NL/Sfe "Space Environmental Effects on the Polymerisation of Composite Structures"). 1. A.Kondyurin, B.Lauke, Polymerisation processes in simulated free space conditions, Proceedings of the 9th International Symposium on Materials in a Space Environment, Noordwijk, The Netherlands, 16-20 June, 2003, ESA SP-540, September 2003, pp.75-80. 2. V.A.Briskman, T.M.Yudina, K.G.Kostarev, A.V.Kondyurin, V.B.Leontyev, M.G.Levkovich, A.L.Mashinsky, G.S.Nechitailo, Polymerization in microgravity as a new process in space technology, Acta Astronautica, vol.48, N2-3, 2001, pp.169-180.

  18. To Create Space on Earth: The Space Environment Simulation Laboratory and Project Apollo

    NASA Technical Reports Server (NTRS)

    Walters, Lori C.

    2003-01-01

    Few undertakings in the history of humanity can compare to the great technological achievement known as Project Apollo. Among those who witnessed Armstrong#s flickering television image were thousands of people who had directly contributed to this historic moment. Amongst those in this vast anonymous cadre were the personnel of the Space Environment Simulation Laboratory (SESL) at the Manned Spacecraft Center (MSC) in Houston, Texas. SESL houses two large thermal-vacuum chambers with solar simulation capabilities. At a time when NASA engineers had a limited understanding of the effects of extremes of space on hardware and crews, SESL was designed to literally create the conditions of space on Earth. With interior dimensions of 90 feet in height and a 55-foot diameter, Chamber A dwarfed the Apollo command/service module (CSM) it was constructed to test. The chamber#s vacuum pumping capacity of 1 x 10(exp -6) torr can simulate an altitude greater than 130 miles above the Earth. A "lunar plane" capable of rotating a 150,000-pound test vehicle 180 deg replicates the revolution of a craft in space. To reproduce the temperature extremes of space, interior chamber walls cool to -280F as two banks of carbon arc modules simulate the unfiltered solar light/heat of the Sun. With capabilities similar to that of Chamber A, early Chamber B tests included the Gemini modular maneuvering unit, Apollo EVA mobility unit and the lunar module. Since Gemini astronaut Charles Bassett first ventured into the chamber in 1966, Chamber B has assisted astronauts in testing hardware and preparing them for work in the harsh extremes of space.

  19. Space Environment Monitoring System in next generation Geostationary Meteorological Satellite of China

    NASA Astrophysics Data System (ADS)

    Xin, Zhang

    Feng Yun 4(FY-4) is a second-generation Meteorological Remote Sensing earth observation satellite of China. On board FY-4, Space Environment Monitoring System(SEMS) consist of seven payloads, including 3 High Energy Particle Detector(HEPD), 1 Magnetometer(MTM), 1 Charging Potential Probe(CPP) and 1 Radiation Dosimeter(RD). High energy particle , magnetic field and space environment effect compose of main goals of SEMS. The HEPD instrument will detect proton with 3 directions , electron with 9 directions. Magnetometer will monitor magnetic field intensity between -400nT and +400nT. CPP will monitor Relative Surface Voltage from -10KV to +1KV, Absolute Surface Voltage from -20KV to -100V ,+100V to +1KV, Deep Surface Voltage from -2.5KV to 0V. RD will monitor dose from 0 rad to 200,000 rad. The first FY-4 satellite is planned to be launched in Dec 2015,This next-generation system will continue to provide more information about space weather, and SEMS will be playing more important role in space weather.

  20. Space Environment Factors Affecting the Performance of International Space Station Materials: The First Two Years of Flight Operations

    NASA Technical Reports Server (NTRS)

    Koontz, Steven L.; Peldey, Michael; Mayeaux, Brian; Milkatarian, Ronald R.; Golden, John; Boeder, paul; Kern, John; Barsamian, Hagop; Alred, John; Soares, Carlos; Christiansen, Eric; Schneider, Todd; Edwards, Dave

    2003-01-01

    In this paper, the natural and induced space environment factors affecting materials performance on ISS are described in some detail. The emphasis will be on ISS flight experience and the more significant design and development issues of the last two years. The intent is to identify and document the set of space environment factors, affecting materials, that are producing the largest impacts on the ISS flight hardware verification and acceptance process and on ISS flight operations. Orbital inclination (S1.6 ) and altitude (nominal3S0 km to 400 km altitude) determine the set of natural environment factors affecting the functional life of materials and subsystems on ISS. ISS operates in the F2 region of Earth's ionosphere in well-defined fluxes of atomic oxygen, other ionospheric plasma species, and solar UV, VUV, and x-ray radiation, as well as galactic cosmic rays, trapped radiation, and solar cosmic rays (1,2). The high latitude orbital environment also exposes external surfaces to significantly less well-defined or predictable fluxes of higher energy trapped electrons and auroral electrons (3 ,4). The micrometeoroid and orbital debris environment is an important determinant of spacecraft design and operations in any orbital inclination. Environment factors induced by ISS flight operations include ram-wake effects, magnetic induction voltages arising from flight through Earth's magnetic field, hypergolic thruster plume impingement from proximity operations of visiting vehicles, materials outgassing, venting and dumping of fluids, ISS thruster operations, as well as specific electrical power system interactions with the ionospheric plasma (S-7). ISS must fly in a very limited number of approved flight attitudes leading to location specific environmental exposures and extreme local thermal environments (8). ISS is a large vehicle and produces a deep wake structure from which both ionospheric plasma and neutrals (atomic oxygen) are largely excluded (9-11). At high

  1. High Temperature Wireless Communication And Electronics For Harsh Environment Applications

    NASA Technical Reports Server (NTRS)

    Hunter, G. W.; Neudeck, P. G.; Beheim, G. M.; Ponchak, G. E.; Chen, L.-Y

    2007-01-01

    In order for future aerospace propulsion systems to meet the increasing requirements for decreased maintenance, improved capability, and increased safety, the inclusion of intelligence into the propulsion system design and operation becomes necessary. These propulsion systems will have to incorporate technology that will monitor propulsion component conditions, analyze the incoming data, and modify operating parameters to optimize propulsion system operations. This implies the development of sensors, actuators, and electronics, with associated packaging, that will be able to operate under the harsh environments present in an engine. However, given the harsh environments inherent in propulsion systems, the development of engine-compatible electronics and sensors is not straightforward. The ability of a sensor system to operate in a given environment often depends as much on the technologies supporting the sensor element as the element itself. If the supporting technology cannot handle the application, then no matter how good the sensor is itself, the sensor system will fail. An example is high temperature environments where supporting technologies are often not capable of operation in engine conditions. Further, for every sensor going into an engine environment, i.e., for every new piece of hardware that improves the in-situ intelligence of the components, communication wires almost always must follow. The communication wires may be within or between parts, or from the engine to the controller. As more hardware is added, more wires, weight, complexity, and potential for unreliability is also introduced. Thus, wireless communication combined with in-situ processing of data would significantly improve the ability to include sensors into high temperature systems and thus lead toward more intelligent engine systems. NASA Glenn Research Center (GRC) is presently leading the development of electronics, communication systems, and sensors capable of prolonged stable

  2. Optimization of piezo-electric PVDF polymers for adaptive optics in space environments.

    SciTech Connect

    Dargaville, Tim Richard; Martin, Jeffrey W.; Clough, Roger Lee; Celina, Mathias Christopher

    2003-07-01

    Piezoelectric polymers based on PVDF are of interest for use in large aperture space-based telescopes similar to the James Web Space Telescope. Dimensional adjustments of polymer films depend on their piezoelectric properties with wireless (electron beam) shape control methods having been successfully demonstrated in the past. Such electron beam controls require a detailed understanding of the piezoelectric material responses. Similarly, space applications demand consistent, predictable, and reliable performance. While PVDF as a generic polymer type is a suitable piezoelectric material, it is also well known that fluorinated polymers are highly radiation-sensitive. Mechanical and other physical properties will suffer under various types of radiation (strong vacuum UV, {gamma}-, X-ray, e-beam, ion-beam) and atomic oxygen exposure. Likewise, extreme temperature fluctuations in space environments will result in annealing effects and cyclic stresses. While the radiative degradation chemistry of polymers is an established field there is little information available on the performance of piezoelectric features in PVDF with respect to their expected changes in these environments. Therefore, understanding such fundamental issues becomes mandatory for the design and deployment of satellite systems utilizing these materials/technology. We have investigated the degradation of PVDF and copolymers under a range of stress environments, and have studied the implications with regard to piezoelectrical properties necessary for reliable operation of thin films in space environments. Initial aging studies using {gamma}- and e-beam irradiation to explore material sensitivities for comparison with expected UV doses have shown complex material changes with lowered Curie temperatures, crystallinity, melting points and significant crosslinking, but little affect on piezoelectric d{sub 33} constants. Similar complexities of the aging processes have been observed in accelerated temperature

  3. An Evaluation of Electronic Nose for Space Program Applications

    NASA Technical Reports Server (NTRS)

    Young, Rebecca C.; Linnell, Bruce R.; Buttner, William J.; Mersqhelte, Barry

    2003-01-01

    The ability to monitor air contaminants in the Shuttle and the International Space Station is important to ensure the health and safety of astronauts. Three specific space applications have been identified that would benefit from a chemical monitor: organic contaminants in crew cabins, propellant contaminants in the airlock, and pre-combustion fire detection. NASA has assessed several commercial and developing electronic noses (e-noses) for these applications. A preliminary series of tests identified those e-noses that exhibited sufficient sensitivity to the vapors of interest. These e-noses were further tested to assess their ability to identify vapors, and in-house software has been developed to enhance identification. This paper describes the tests, the classification ability of selected e-noses, and the software improvements made to meet the requirements for these space program applications.

  4. Packaging films for electronic and space-related hardware

    NASA Astrophysics Data System (ADS)

    Shon, E. M.; Hamberg, O.

    1985-08-01

    Flexible packaging films are used to bag and/or wrap precision cleaned electronic or space hardware to protect them from environmental degradation during shipping and storage. Selection of packaging films depends on a knowledge of product requirements and packaging film characteristics. The literature presently available on protective packaging films has been updated to include new materials and to amplify space-related applications. Presently available packaging film materials are compared for their various characteristics: electrostatic discharge (ESD) control, flame retardancy, water vapor transmission rate, particulate shedding, molecular contamination, and transparency. The tradeoff between product requirements and the characteristics of the packaging films available are discussed. Selection considerations are given for the application of specific materials of space hardware-related applications. Applications for intimate, environmental, and electrostatic protective packaging are discussed.

  5. Space Suit Radiator Performance in Lunar and Mars Environments

    NASA Technical Reports Server (NTRS)

    Paul, Heather; Trevino, Luis; Nabity, James; Mason, Georgia; Copeland, Robert; Libberton, Kerry; Stephan, Ryan

    2007-01-01

    During an ExtraVehicular Activity (EVA), both the heat generated by the astronaut's metabolism and that produced by the Portable Life Support System (PLSS) must be rejected to space. The heat sources include the heat of adsorption of metabolic CO2, the heat of condensation of water, the heat removed from the body by the liquid cooling garment and the load from the electrical components. Although the sublimator hardware to reject this load weighs only 3.48 lbs, an additional eight pounds of water are loaded into the unit of which about six to eight are sublimated and lost; this is the single largest expendable during an eight-hour EVA. Using a radiator to reject heat from the Astronaut during an EVA, we can significantly reduce the amount of expendable water consumed by the sublimator. Last year we reported on the design and initial operational assessment tests of our novel radiator designated the Radiator And Freeze Tolerant heat eXchanger (RAFT-X). Herein, we report on tests conducted in the NASA Johnson Space Center Chamber E Thermal Vacuum Test Facility. Up to 800 Btu/h of heat were rejected in lunar and Mars environments with temperatures as cold as 150 F. Tilting the radiator did not cause an observable loss in performance. The RAFT-X endured freeze/thaw cycles and in fact, the heat exchanger was completely frozen three times without any apparent damage to the unit. We were also able to operate the heat exchanger in a partially frozen configuration to throttle the heat rejection rate from 530 Btu/h at low water flow rate down to 300 Btu/h. Finally, the deliberate loss of a single loop heat pipe only degraded the heat rejection performance by about 2 to 5%.

  6. Space Suit Radiator Performance in Lunar and Mars Environments

    NASA Technical Reports Server (NTRS)

    Nabity, James; Mason, Georgia; Copeland, Robert; Libberton, Kerry; Trevino, Luis; Stephan, Ryan; Paul, Heather

    2007-01-01

    During an ExtraVehicular Activity (EVA), both the heat generated by the astronaut's metabolism and that produced by the Portable Life Support System (PLSS) must be rejected to space. The heat sources include the heat of adsorption of metabolic CO2, the heat of condensation of water, the heat removed from the body by the liquid cooling garment and the load from the electrical components. Although the sublimator hardware to reject this load weighs only 3.48 lbs, an additional eight pounds of water are loaded into the unit of which about six to eight are sublimated and lost; this is the single largest expendable during an eight-hour EVA. Using a radiator to reject heat from the Astronaut during an EVA, we can significantly reduce the amount of expendable water consumed by the sublimator. Last year we reported on the design and initial operational assessment tests of our novel radiator designated the Radiator And Freeze Tolerant heat eXchanger (RAFT-X). Herein, we report on tests conducted in the NASA Johnson Space Center Chamber E Thermal Vacuum Test Facility. Up to 800 Btu/h of heat were rejected in lunar and Mars environments with temperatures as cold as -150 F. Tilting the radiator did not cause an observable loss in performance. The RAFT-X endured freeze / thaw cycles and in fact, the heat exchanger was completely frozen three times without any apparent damage to the unit. We were also able to operate the heat exchanger in a partially frozen configuration to throttle the heat rejection rate from 530 Btu/h at low water flow rate down to 300 Btu/h. Finally, the deliberate loss of a single loop heat pipe only degraded the heat rejection performance by about 2 to 5%.

  7. The Charging of Composites in the Space Environment

    NASA Technical Reports Server (NTRS)

    Czepiela, Steven A.

    1997-01-01

    Deep dielectric charging and subsequent electrostatic discharge in composite materials used on spacecraft have become greater concerns since composite materials are being used more extensively as main structural components. Deep dielectric charging occurs when high energy particles penetrate and deposit themselves in the insulating material of spacecraft components. These deposited particles induce an electric field in the material, which causes the particles to move and thus changes the electric field. The electric field continues to change until a steady state is reached between the incoming particles from the space environment and the particles moving away due to the electric field. An electrostatic discharge occurs when the electric field is greater than the dielectric strength of the composite material. The goal of the current investigation is to investigate deep dielectric charging in composite materials and ascertain what modifications have to be made to the composite properties to alleviate any breakdown issues. A 1-D model was created. The space environment, which is calculated using the Environmental Workbench software, the composite material properties, and the electric field and voltage boundary conditions are input into the model. The output from the model is the charge density, electric field, and voltage distributions as functions of the depth into the material and time. Analysis using the model show that there should be no deep dielectric charging problem with conductive composites such as carbon fiber/epoxy. With insulating materials such as glass fiber/epoxy, Kevlar, and polymers, there is also no concern of deep dielectric charging problems with average day-to-day particle fluxes. However, problems can arise during geomagnetic substorms and solar particle events where particle flux levels increase by several orders of magnitude, and thus increase the electric field in the material by several orders of magnitude. Therefore, the second part of this

  8. Evaluation of Power Electronic Components and Systems at Cryogenic Temperatures For Space Missions

    NASA Technical Reports Server (NTRS)

    Elbuluk, Malik E.; Gerber, Scott; Hammoud, Ahmad; Patterson, Richard L.

    2005-01-01

    Power electronic circuits and systems designed for deep space applications and outer planetary exploration are required to operate reliably and efficiently under extreme temperature conditions. This requirement is dictated by the fact that the operational environments associated with some of the space missions would encompass temperatures as low as -183 C. The development and utilization of electronics capable of low temperature operation would not only fulfill the advanced technology requirements, but also would contribute to improving circuit performance, increasing system efficiency, and reducing development and launch costs. These benefits are generally achieved by the improved intrinsic properties of some of the electronic materials at low temperature, reduced device losses, and the elimination of heating elements used in conventional systems at low temperatures. Power electronic circuits are widely used in space power systems in the areas of power management, conditioning, and control. In this work, the performance of certain power electronic components and systems was investigated under low temperature. These include inductors, capacitors, pulse-width-modulation (PWM) controllers, and advanced commercial DC/DC converter modules. Different properties were determined as a function of temperature in the range of 20 C to -140 C, at various current and voltages levels. The experimental procedures along with the experimental data obtained are presented and discussed in this paper.

  9. Basic mechanisms of radiation effects in the natural space radiation environment

    SciTech Connect

    Schwank, J.R.

    1994-06-01

    Four general topics are covered in respect to the natural space radiation environment: (1) particles trapped by the earth`s magnetic field, (2) cosmic rays, (3) radiation environment inside a spacecraft, (4) laboratory radiation sources. The interaction of radiation with materials is described by ionization effects and displacement effects. Total-dose effects on MOS devices is discussed with respect to: measurement techniques, electron-hole yield, hole transport, oxide traps, interface traps, border traps, device properties, case studies and special concerns for commercial devices. Other device types considered for total-dose effects are SOI devices and nitrided oxide devices. Lastly, single event phenomena are discussed with respect to charge collection mechanisms and hard errors. (GHH)

  10. Optical Analysis of Transparent Polymeric Material Exposed to Simulated Space Environment

    NASA Technical Reports Server (NTRS)

    Edwards, David L.; Finckenor, Miria M.

    2000-01-01

    Many innovations in spacecraft power and propulsion have been recently tested at NASA, particularly in non-chemical propulsion. One improvement in solar array technology is solar concentration using thin polymer film Fresnel lenses. Weight and cost savings were proven with the Solar Concentrator Arrays with Refractive Linear Element Technology (SCARLET)-II array on NASA's Deep Space I spacecraft. The Fresnel lens concentrates solar energy onto high-efficiency solar cells, decreasing the area of solar cells needed for power. Continued efficiency of this power system relies on the thin film's durability in the space environment and maintaining transmission in the 300 - 1000 nm bandwidth. Various polymeric materials have been tested for use in solar concentrators, including Lexan(TM), polyethylene terephthalate (PET), several formulations of Tefzel(Tm) and Teflon(TM), and DC 93-500, the material selected for SCARLET-II. Also tested were several innovative materials including Langley Research Center's CPI and CP2 polymers and atomic oxygen- resistant polymers developed by Triton Systems, Inc. The Environmental Effects Group of the Marshall Space Flight Center's Materials, Processes, and Manufacturing Department exposed these materials to simulated space environment and evaluated them for any change in optical transmission. Samples were exposed to a minimum of 1000 equivalent Sun hours of near-UV radiation (250 - 400 nm wavelength). Materials that appeared robust after near-UV exposure were then exposed to charged particle radiation equivalent to a five-year dose in geosynchronous orbit. These exposures were performed in MSFC's Combined Environmental Effects Test Chamber, a unique facility with the capability to expose materials simultaneously or sequentially to protons, low-energy electrons, high-energy electrons, near UV radiation and vacuum UV radiation. Reflectance measurements can be made on the samples in vacuum. Prolonged exposure to the space environment will

  11. High-temperature electronics applications in space exploration

    NASA Technical Reports Server (NTRS)

    Jurgens, R. F.

    1982-01-01

    One of the most exciting applications of high-temperature electronics is related to the exploration of the planet Venus. On this planet the atmospheric temperatures range from about 170 K at elevations of 100 km to a searing 730 K near the surface. Mechanisms for exploring the atmosphere might include balloons, airplanes, surface landers, and surface-launched probes. Balloons, for example, could fly in the region from 20 (320 C at 22 bars) to 60 km (-20 C at 0.2 bar). Suitable balloon fabrics presently exclude excursions to lower altitudes; however, adequate electronic systems could survive to 325 C. Small airplanes would require more sophisticated electronics for guidance and control. Long life surface landers would most likely be developed first, as these could be used to measure long-term variations in weather. Ranging transponders would be important for ephemeris development, measurement of spin state, and studies of general relativity. Surface temperatures of 460 C and pressures of 90 bars present a challenge to the developers of such instruments. Other space applications for high-temperature electronics include transponders for the surface of Mercury, near solar drag-free orbiters, and deep atmospheric penetrators for Jupiter and Saturn. Each of these has its own particular problems with respect to instrumentation adequate to meet the desired scientific goals. This paper is primarily concerned with defining possible mission applications, the required electronic systems, and the approaches that are currently being studied for their development.

  12. Surface analyses of composites exposed to the space environment on LDEF

    NASA Technical Reports Server (NTRS)

    Mallon, Joseph J.; Uht, Joseph C.; Hemminger, Carol S.

    1992-01-01

    We have conducted a series of surface analyses on carbon fiber/polyarylacetylene matrix composites that were exposed to the space environment on the LDEF satellite. None of the composites were catastrophically damaged by nearly six years of exposure to the space environment. Composites on the leading edge exhibited about 5 mils of surface erosion, but trailing edge panels exhibited no physical appearance changes due to exposure. Scanning electron microscopy (SEM) was used to show that the erosion morphology on the leading edge samples was dominated by crevasses parallel to the fibers with triangular cross sections 10 to 100 microns in depth. The edges of the crevasses were well defined and penetrated through both matrix and fiber. The data suggest that the carbon fibers are playing a significant role in crevasse initiation and/or enlargement, and in the overall erosion rate of the composite. X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray spectroscopy (EDS) results showed the presence of silicone and hydrocarbon contamination from in-flight sources. The role of contamination in crevasse initiation and enlargement is unknown at this time. These LDEF results demonstrate that the prediction of long term atomic oxygen erosion morphology for composite materials from erosion data obtained on short Space Shuttle missions is difficult. A better understanding of other factors such as thermal cycling and UV exposure which may influence erosion is necessary to improve the accuracy of the predictions.

  13. Direct longitudinal laser acceleration of electrons in free space

    NASA Astrophysics Data System (ADS)

    Carbajo, Sergio; Nanni, Emilio A.; Wong, Liang Jie; Moriena, Gustavo; Keathley, Phillip D.; Laurent, Guillaume; Miller, R. J. Dwayne; Kärtner, Franz X.

    2016-02-01

    Compact laser-driven accelerators are pursued heavily worldwide because they make novel methods and tools invented at national laboratories widely accessible in science, health, security, and technology [V. Malka et al., Principles and applications of compact laser-plasma accelerators, Nat. Phys. 4, 447 (2008)]. Current leading laser-based accelerator technologies [S. P. D. Mangles et al., Monoenergetic beams of relativistic electrons from intense laser-plasma interactions, Nature (London) 431, 535 (2004); T. Toncian et al., Ultrafast laser-driven microlens to focus and energy-select mega-electron volt protons, Science 312, 410 (2006); S. Tokita et al. Single-shot ultrafast electron diffraction with a laser-accelerated sub-MeV electron pulse, Appl. Phys. Lett. 95, 111911 (2009)] rely on a medium to assist the light to particle energy transfer. The medium imposes material limitations or may introduce inhomogeneous fields [J. R. Dwyer et al., Femtosecond electron diffraction: "Making the molecular movie,", Phil. Trans. R. Soc. A 364, 741 (2006)]. The advent of few cycle ultraintense radially polarized lasers [S. Carbajo et al., Efficient generation of ultraintense few-cycle radially polarized laser pulses, Opt. Lett. 39, 2487 (2014)] has ushered in a novel accelerator concept [L. J. Wong and F. X. Kärtner, Direct acceleration of an electron in infinite vacuum by a pulsed radially polarized laser beam, Opt. Express 18, 25035 (2010); F. Pierre-Louis et al. Direct-field electron acceleration with ultrafast radially polarized laser beams: Scaling laws and optimization, J. Phys. B 43, 025401 (2010); Y. I. Salamin, Electron acceleration from rest in vacuum by an axicon Gaussian laser beam, Phys. Rev. A 73, 043402 (2006); C. Varin and M. Piché, Relativistic attosecond electron pulses from a free-space laser-acceleration scheme, Phys. Rev. E 74, 045602 (2006); A. Sell and F. X. Kärtner, Attosecond electron bunches accelerated and compressed by radially polarized laser

  14. Severe shock and vibration environments for electronic components

    SciTech Connect

    Martinez, D.R.

    1990-01-01

    Electronic components used in system applications must be qualified to mechanical shock and vibration environments. Often these environments are severe, requiring the development and use of special test techniques and procedures. Environmental specifications are based upon analytical model predictions and measured test data. Test specifications are determined after careful consideration of simulation techniques, input levels, dynamic behavior of the test fixturing, as well as an assessment of the degree of conservatism imposed by the specification and testing procedures. The process of determining component shock and vibration specifications is discussed, beginning with the initial description of system and subsystem level environments, and concluding with component level test specifications. Included is a discussion of the difference between environmental specifications and test specifications, and the instrumentation/measurement problems associated with obtaining valid field measurements for severe shock data. The role of finite element analysis in predicting the dynamic structural response of components is also explained. Shock data analysis techniques are described including both time-domain and frequency-domain characterizations of the data. The resonant plate shock testing technique for simulating severe shock environments is presented, including difficulties that arise in practical applications. 18 refs., 10 figs.

  15. Current Space Station Experiments Investigating Component Level Electronics Repair

    NASA Technical Reports Server (NTRS)

    Easton, John W.; Struk, Peter M.

    2010-01-01

    The Soldering in a Reduced Gravity Experiment (SoRGE) and Component Repair Experiment (CRE)-1 are tests performed on the International Space Station to determine the techniques, tools, and training necessary to allow future crews to perform manual electronics repairs at the component level. SoRGE provides information on the formation and internal structure of through-hole solder joints, illustrating the challenges and implications of soldering in reduced gravity. SoRGE showed a significant increase in internal void defects for joints formed in low gravity compared to normal gravity. Methods for mitigating these void defects were evaluated using a modified soldering process. CRE-1 demonstrated the removal, cleaning, and replacement of electronics components by manual means on functional circuit boards. The majority of components successful passed a post-repair functional test demonstrating the feasibility of component-level repair within the confines of a spacecraft. Together, these tasks provide information to recommend material and tool improvements, training improvements, and future work to help enable electronics repairs in future space missions.

  16. Radiation from Electron Phase Space Holes as a Possible Source of Jovian S-bursts

    NASA Astrophysics Data System (ADS)

    Goodrich, Katherine; Ergun, Robert; Holmes, Justin

    2016-04-01

    Radio-frequency short burst emissions (10-40 MHz), known as Jovian S-bursts, have been observed from the Jovian aurora for over fifty years. These emissions, associated with Io's motion, have a rapidly declining frequency and an exceptionally narrow bandwidth. While it is widely believed that S-bursts are generated by the electron cyclotron maser instability, the mechanism responsible for the rapidly declining frequency and narrow bandwidth currently is not well established. We explore a hypothesis that electron phase space holes radiate or stimulate radiation in the Jovian aurora plasma environment as a possible source of S-burst emissions. Electron phase-space holes (EHs) are ubiquitous in an auroral environment and travel at the implied speeds (˜20,000 km/s) of the structures creating the Jovian S-bursts. Furthermore, EHs have the proper physical size to create the observed bandwidth, have sufficient energy content, and can create an environment whereby X mode emissions can be excited. If verified, these findings imply that EHs may be an important source of radiation from strongly magnetized or relativistic astrophysical plasmas.

  17. The Cassini Radio & Plasma Wave Science (RPWS) view of the Enceladus Space Environment

    NASA Astrophysics Data System (ADS)

    Wahlund, Jan-Erik; Gurnett, Donald; Kurth, William; Andrews, David; Engelhardt, Ilka; Eriksson, Anders; Farrell, William; Holmberg, Mika; Hospodarsky, George; Morooka, Michiko; Sheng-Yi, Ye; Vigren, Erik

    2014-05-01

    A physical picture of the interaction between Saturn's magnetosphere and the moon Enceladus space environment is presented based on Radio and Plasma Wave Science (RPWS) observations. The space environment around Enceladus consists of several different regions with a diversity of active physical processes. Foremost, the southward exhaust plume reveals a cold, dense, conductive and dusty plasma environment where the magnetic field is piled-up. Plasma acceleration processes are active at the plume edges, and constitute an important part of the electrodynamic MHD dynamo, giving rise to Auroral hiss emissions as well as a magnetic footprint pattern in the high-latitude atmosphere of Saturn. The Enceladus wake is filled with negatively charged dust that depletes the region from electrons by water grain attachment. The grains around Enceladus can be picked-up by the magnetospheric co-rotation electric field. The charged water grains then populate the region in Enceladus orbit around Saturn and create the E-ring. Depending on the size of the grains, different grain evolutions occur and different dynamics of the grains are expected. The Enceladus plume as well as the plasma disc surrounding the E-ring constitutes complex natural laboratories for dust-plasma interaction, which has important implications also for the newly discovered Europa plume and associated plasma disk material around Jupiter to be investigated by the ESA JUICE and the NASA Europa Clipper missions. We present a detailed account of the Cassini RPWS observations around Enceladus with associated physical interpretations.

  18. Thermally Induced Vibrations of the Hubble Space Telescope's Solar Array 3 in a Test Simulated Space Environment

    NASA Technical Reports Server (NTRS)

    Early, Derrick A.; Haile, William B.; Turczyn, Mark T.; Griffin, Thomas J. (Technical Monitor)

    2001-01-01

    NASA Goddard Space Flight Center and the European Space Agency (ESA) conducted a disturbance verification test on a flight Solar Array 3 (SA3) for the Hubble Space Telescope using the ESA Large Space Simulator (LSS) in Noordwijk, the Netherlands. The LSS cyclically illuminated the SA3 to simulate orbital temperature changes in a vacuum environment. Data acquisition systems measured signals from force transducers and accelerometers resulting from thermally induced vibrations of the SAI The LSS with its seismic mass boundary provided an excellent background environment for this test. This paper discusses the analysis performed on the measured transient SA3 responses and provides a summary of the results.

  19. Space Environment Effects on Stability of Medications Flown on Space Shuttles and the International Space Station (ISS)

    NASA Technical Reports Server (NTRS)

    Daniels, Vernie; Du, Jianping; Crady, Camille; Satterfield, Rick; Putcha, Lakshmi

    2007-01-01

    The purpose is to assess physical and chemical degradation of select pharmaceutical formulations from the Shuttle and ISS medical kits. Eleven pharmaceuticals dispensed as different dosage forms were selected based on their physical / chemical characteristics and susceptibility to environmental factors such as, temperature, humidity and light sensitivity. When available, ground-controls of the study medications with matching brand and lot numbers were used for comparison. Samples retrieved from flight were stored along with their matching controls in a temperature and humidity controlled environmental chamber. Temperature, humidity, and radiation data from the Shuttle and ISS were retrieved from onboard HOBO U12 Temp/RH Data Loggers, and from passive dosimeters. Physical and chemical analyses of the pharmaceuticals were conducted using validated United States Pharmacopeia (USP) methods. Results indicated degradation of 6 of the 11 formulations returned from space flights. Four formulations, Amoxicillin / Clavulanate, promethazine, sulfamethoxazole / trimethoprim, and ciprofloxacin tablets depicted discoloration after flight. Chemical content analyses using High or Ultra Performance Liquid Chromatography (HPLC / UPLC) methods revealed that dosage forms of Amoxicillin / Clavulanate, promethazine, sulfamethoxazole / trimethoprim, lidocaine, ciprofloxacin and mupirocin contained less than 95% of manufacturer s labeled claim of active drug compound. Shuttle and ISS environments affect stability and shelf life of certain mediations flown on these missions. Data analysis is in progress to examine the effect of specific space flight environmental factors on pharmaceutical stability. The degradation profiles generated from ground studies in analog environments will be useful in establishing predictive shelf-life profiles for medications intended for use during long-term space exploration missions.

  20. The effects of the space environment on two aramid materials

    NASA Technical Reports Server (NTRS)

    Kiefer, Richard L.

    1990-01-01

    Two aramid fibers having closely related chemical structures were chosen for important roles in the first tether to be used to connect pairs of orbiting vehicles. The protective outer jackets of the tethers will consist of woven fibers of poly(m-phenylene isophthalamide), commercially available from du Pont as Nomex. A cylindrical sheath of woven Kevlar 29, whose principal constituent is poly(p-phenylene terephthalamide), will be the load-bearing component for the tethers. Orbiting tethers will be in a hostile environment in which short wavelength electromagnetic radiation and energetic charged particles degrade exposed organic materials. At lower orbiting altitudes atomic oxygen is an especially serious hazard. Studies on the effects of ultraviolet radiation and atomic oxygen on fibers and films of Kevlar and Nomex are in progress. In an experiment to simulate the effects of atomic oxygen in space, small tows of Kevlar and Nomex were mounted in a commercial ashing device filled with oxygen at low pressure. An RF discharge in the instrument dissociated the molecular oxygen producing a strongly oxidizing atmosphere containing O(3P)(sup 4). Erosion was measured in terms of mass loss. Kevlar films were exposed to UV radiation in an apparatus consisting of a small vacuum chamber, 23 cm in diameter, into which a mass spectrometer and a quartz window were incorporated. Samples were exposed under vacuum with a 1000 watt xenon-arc lamp. Volatile products could be monitored with the mass spectrometer during the exposures. Transmission infrared spectra were taken before and after exposure to monitor chemical changes in the films.

  1. Application of Advanced Materials Protecting from Influence of Free Space Environment

    NASA Astrophysics Data System (ADS)

    Dotsenko, Oleg; Shovkoplyas, Yuriy

    2016-07-01

    High cost and low availability of the components certified for use in the space environment forces satellite designers to using industrial and even commercial items. Risks associated with insufficient knowledge about behavior of these components in radiation environment are parried, mainly, by careful radiating designing of a satellite where application of special protective materials with improved space radiation shielding characteristics is one of the most widely used practices. Another advantage of protective materials application appears when a satellite designer needs using equipment in more severe space environment conditions then it has been provided at the equipment development. In such cases only expensive repeated qualification of the equipment hardness can be alternative to protective materials application. But mostly this way is unacceptable for satellite developers, being within strong financial and temporal restrictions. To apply protective materials effectively, the developer should have possibility to answer the question: "Where inside a satellite shall I place these materials and what shall be their shape to meet the requirements on space radiation hardness with minimal mass and volume expenses?" At that, the minimum set of requirements on space radiation hardness include: ionizing dose, nonionizing dose, single events, and internal charging. The standard calculative models and experimental techniques, now in use for space radiation hardness assurance of a satellite are unsuitable for the problem solving in such formulation. The sector analysis methodology, widely used in satellite radiating designing, is applicable only for aluminium shielding and doesn't allow taking into account advantages of protective materials. The programs simulating transport of space radiations through a substance with the use of Monte-Carlo technique, such as GEANT4, FLUKA, HZETRN and others, are fully applicable in view of their capabilities; but time required for

  2. Design of space-type electronic power transformers

    NASA Technical Reports Server (NTRS)

    Ahearn, J. F.; Lagadinos, J. C.

    1977-01-01

    Both open and encapsulated varieties of high reliability, low weight, and high efficiency moderate and high voltage transformers were investigated to determine the advantages and limitations of their construction in the ranges of power and voltage required for operation in the hard vacuum environment of space. Topics covered include: (1) selection of the core material; (2) preliminary calculation of core dimensions; (3) selection of insulating materials including magnet wire insulation, coil forms, and layer and interwinding insulation; (4) coil design; (5) calculation of copper losses, core losses and efficiency; (6) calculation of temperature rise; and (7) optimization of design with changes in core selection or coil design as required to meet specifications.

  3. Vulnerability assessment of a space based weapon platform electronic system exposed to a thermonuclear weapon detonation

    SciTech Connect

    Perez, C.L.; Johnson, J.O.

    1994-03-01

    Rapidly changing world events, the increased number of nations with inter-continental ballistic missile capability, and the proliferation of nuclear weapon technology will increase the number of nuclear threats facing the world today. Monitoring these nation`s activities and providing an early warning and/or intercept system via reconnaissance and surveillance satellites and space based weapon platforms is a viable deterrent against a surprise nuclear attack. However, the deployment of satellite and weapon platform assets in space will subject the sensitive electronic equipment to a variety of natural and man-made radiation environments. These include Van Allen Belt protons and electrons; galactic and solar flare protons; and, neutrons, gamma rays, and X-rays from intentionally detonated fission and fusion weapons. In this paper, the MASH vl.0 code system is used to estimate the dose to the critical electronics components of an idealized space based weapon platform from neutron and gamma-ray radiation emitted from a thermonuclear weapon detonation in space. Fluence and dose assessments were performed for the platform fully loaded, and in several stages representing limited engagement scenarios. The results indicate vulnerabilities to the Command, Control, and Communication (C) bay instruments from radiation damage for a nuclear weapon detonation for certain source/platform orientations. The distance at which damage occurs will depend on the weapon yield (n,{gamma}/kiloton) and size (kilotons).

  4. MOSES: a modular sensor electronics system for space science and commercial applications

    NASA Astrophysics Data System (ADS)

    Michaelis, Harald; Behnke, Thomas; Tschentscher, Matthias; Mottola, Stefano; Neukum, Gerhard

    1999-10-01

    The camera group of the DLR--Institute of Space Sensor Technology and Planetary Exploration is developing imaging instruments for scientific and space applications. One example is the ROLIS imaging system of the ESA scientific space mission `Rosetta', which consists of a descent/downlooking and a close-up imager. Both are parts of the Rosetta-Lander payload and will operate in the extreme environment of a cometary nucleus. The Rosetta Lander Imaging System (ROLIS) will introduce a new concept for the sensor electronics, which is referred to as MOSES (Modula Sensor Electronics System). MOSES is a 3D miniaturized CCD- sensor-electronics which is based on single modules. Each of the modules has some flexibility and enables a simple adaptation to specific application requirements. MOSES is mainly designed for space applications where high performance and high reliability are required. This concept, however, can also be used in other science or commercial applications. This paper describes the concept of MOSES, its characteristics, performance and applications.

  5. Evaluation of the effects of solar radiation on glass. [space environment simulation

    NASA Technical Reports Server (NTRS)

    Firestone, R. F.; Harada, Y.

    1979-01-01

    The degradation of glass used on space structures due to electromagnetic and particulate radiation in a space environment was evaluated. The space environment was defined and a simulated space exposure apparatus was constructed. Four optical materials were exposed to simulated solar and particulate radiation in a space environment. Sapphire and fused silica experienced little change in transmittance, while optical crown glass and ultra low expansion glass darkened appreciably. Specimen selection and preparation, exposure conditions, and the effect of simulated exposure are discussed. A selective bibliography of the effect of radiation on glass is included.

  6. Radiation from long pulse train electron beams in space plasmas

    NASA Technical Reports Server (NTRS)

    Harker, K. J.; Banks, P. M.

    1985-01-01

    A previous study of electromagnetic radiation from a finite train of electron pulses is extended to an infinite train of such pulses. The electrons are assumed to follow an idealized helical path through a space plasma in such a manner as to retain their respective position within the beam. This leads to radiation by coherent spontaneous emission. The waves of interest in this region are the whistler slow (compressional) and fast (torsional) Alfven waves. Although a general theory is developed, analysis is then restricted to two approximations, the short and long electron beam. Formulas for the radiation per unit solid angle from the short beam are presented as a function of both propagation and ray angles, electron beam pulse width and separation and beam current, voltage, and pitch angle. Similar formulas for the total power radiated from the long beam are derived as a function of frequency, propagation angle, and ray angle. Predictions of the power radiated are presented for representative examples as determined by the long beam theory.

  7. A New Scenario for the Production of Weak Bipolar Fields in Space: "Notch" Instabilities Resulting From Electron Velocity Dispersion*

    NASA Astrophysics Data System (ADS)

    Newman, D. L.; Goldman, M. V.

    2007-05-01

    The bipolar signatures of weak (eφmax/Te ≪ 1) electron phase-space holes have now been observed in numerous near-Earth space-plasma environments such as the polar cusp region1 and the solar wind2 at 1 AU. While families of stationary solutions of the Vlasov-Poisson equations consistent with these observations have been found,3 the question of how shallow phase-space density depressions supporting these bipolar fields form remains an open one. While strong bipolar fields associated with deep phase-space holes in Earth auroral downward-current region are consistent with saturated two-stream instabilities resulting from double-layer electron acceleration,4 the weak bipolar fields observed in other space environments may require an alternative generation mechanism. One such mechanism involves the formation of narrow minima in the electron velocity-space distribution resulting from stretching due to velocity dispersion of phase-space density minima that are initially localized in physical space (e.g., constant-density regions with temperatures greater than their surroundings). These velocity-space minima, which become narrower as they are dispersively stretched, eventually cross the threshold condition for a "notch" instability, which saturates by forming an expanding series of shallow phase-space holes and their associated weak bipolar fields. 1-D Vlasov-Poisson simulations show that this process can be a robust mechanism for generating a large ensemble of shallow holes. Simulations with different background electron distributions show that the properties of the holes that form depend sensitively on the characteristics of the embedding plasma environment. * Research supported by NSF, NASA, and DOE. 1 J. R. Franz, et al., JGR, 110, doi:10.1029/2005JA011095 (2005). 2 A. Mangeney, private communication. 3 M. V. Goldman, et al., this meeting. 4 R. E. Ergun, et al., PRL, 87, 045003 (2001); D. L. Newman, et al. PRL, 87, 255001 (2001).

  8. Electron Emission Properties of Insulator Materials Pertinent to the International Space Station

    NASA Technical Reports Server (NTRS)

    Thomson, C. D.; Zavyalov, V.; Dennison, J. R.; Corbridge, Jodie

    2004-01-01

    We present the results of our measurements of the electron emission properties of selected insulating and conducting materials used on the International Space Station (ISS). Utah State University (USU) has performed measurements of the electron-, ion-, and photon-induced electron emission properties of conductors for a few years, and has recently extended our capabilities to measure electron yields of insulators, allowing us to significantly expand current spacecraft material charging databases. These ISS materials data are used here to illustrate our various insulator measurement techniques that include: i) Studies of electron-induced secondary and backscattered electron yield curves using pulsed, low current electron beams to minimize deleterious affects of insulator charging. ii) Comparison of several methods used to determine the insulator 1st and 2nd crossover energies. These incident electron energies induce unity total yield at the transition between yields greater than and less than one with either negative or positive charging, respectively. The crossover energies are very important in determining both the polarity and magnitude of spacecraft surface potentials. iii) Evolution of electron emission energy spectra as a function of insulator charging used to determine the surface potential of insulators. iv) Surface potential evolution as a function of pulsed-electron fluence to determine how quickly insulators charge, and how this can affect subsequent electron yields. v) Critical incident electron energies resulting in electrical breakdown of insulator materials and the effect of breakdown on subsequent emission, charging and conduction. vi) Charge-neutralization techniques such as low-energy electron flooding and UV light irradiation to dissipate both positive and negative surface potentials during yield measurements. Specific ISS materials being tested at USU include chromic and sulfuric anodized aluminum, RTV-silicone solar array adhesives, solar cell

  9. 32 CFR 2001.23 - Classification marking in the electronic environment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... INFORMATION SECURITY OVERSIGHT OFFICE, NATIONAL ARCHIVES AND RECORDS ADMINISTRATION CLASSIFIED NATIONAL SECURITY INFORMATION Identification and Markings § 2001.23 Classification marking in the electronic environment. (a) General. Classified national security information in the electronic environment shall be:...

  10. Re-Configurable Electronics Characterization under Extreme Thermal Environment

    NASA Technical Reports Server (NTRS)

    Stoica, Adrian; Lacayo, Veronica; Ramesham, Rajeshuni; Keymeulen, Didier; Zebulum, Ricardo; Neff, Joe; Burke, Gary; Daud, Taher

    2005-01-01

    The need for reconfigurable electronics is driven by requirements to survive longer missions and harsher environments. It is possible to compensate for degradations in Extreme Environments (EE). EE has effect on electronics: circuits are designed to exploit device characteristics and when a certain temperature or radiation range is exceeded the circuit function gradually degrades. It is possible to employ Hardening by reconfiguration (HBR) to mitigate drifts, degradation, or damage on electronic devices in EE by using reconfigurable devices and an adaptive self-reconfiguration of circuit topology. In this manner degraded components can be salvaged, and completely damaged components can be bypassed. The challenge of conventional design is replaced with that of designing a recover process that automatically performs the (re) design in place of the designer. The objective of testing a Digital Signal Processor (DSP) under the extreme temperatures was to determine the lowest temperature at which the DAP can operate. The objective of testing a Xilinx VirtexII Pro FPGA board was to initially find our whether the evaluation board and the FPGA would survive and continue at temperature ranges from -180 C, and 120 C. The Virtex II functioned correctly at the temperatures tested. The next test was done on the GM-C filter building block using the same temperature range as the Virtex II. The current lower and upper limits were shown to be reduced as the temperature gets lower. The device function can be recovered by increasing the Vb from .08V to .85V. The negative and positive saturation voltages increases as the temperature gets higher. The function of the device can be recovered by decreasing the Vb from .8V to around .75V. The next test was performed to test the recovery of the GmC low pass filter through Vb in a filter circuit. The test indicate that bias voltage control adjustment is an efficient mechanism for circuit recovery at extreme temperatures.

  11. Study on the effects of the space environment on laser transmission characteristics

    NASA Astrophysics Data System (ADS)

    Fu, Qiang; Liu, Peng; Tong, Shoufen; Zhang, Peng

    2014-11-01

    Laser space communication has obvious advantages in interstellar transmission - but the space environment will have a direct impact on laser communication system. The function of the analysis of space environment identity effectively could reduce and avoid the bug and invalidation produced by the overload to prolong the using span of effective load and increase the credibility of effective load, meanwhile it is also the main principle to design and research .This article summarizes the characteristics of vacuum space environment(Effect of vacuum outlet, Molecular contamination effect, Vacuum Mount, Cold welding effect, Heat radiation effect under vacuum), low temperature environment, background radiation (including space background radiation caused by thermal radiation, space background radiation caused by light noise). Space background radiation for the performance of space laser communication load is two aspects: one is the background of space radiation caused by thermal radiation, it mainly affects the satellite platform and payload of the thermal control design; Background spectrum caused by radiation and space, it will affect the space laser communication of the signal-to-noise ratio of the receiving unit, which affect the acquisition probability, tracking accuracy and error rate of communication, and particle radiation environment (Including total dose effects, single event effect), the plasma environment in five areas from the characteristics of space environment, for the problem of Space channel Influence the laser communication system performance. On this basis ,this article analysis the influence of space environment on the laser communication system with some examples, which will lay the foundation for the application of space laser communication system of our country.

  12. Space radiation shielding studies for astronaut and electronic component risk assessment

    NASA Astrophysics Data System (ADS)

    Fuchs, Jordan; Gersey, Brad; Wilkins, Richard

    The space radiation environment is comprised of a complex and variable mix of high energy charged particles, gamma rays and other exotic species. Elements of this radiation field may also interact with intervening matter (such as a spaceship wall) and create secondary radiation particles such as neutrons. Some of the components of the space radiation environment are highly penetrating and can cause adverse effects in humans and electronic components aboard spacecraft. Developing and testing materials capable of providing effective shielding against the space radiation environment presents special challenges to researchers. Researchers at the Cen-ter for Radiation Engineering and Science for Space Exploration (CRESSE) at Prairie View AM University (PVAMU) perform accelerator based experiments testing the effectiveness of various materials for use as space radiation shields. These experiments take place at the NASA Space Radiation Laboratory at Brookhaven National Laboratory, the proton synchrotron at Loma Linda University Medical Center, and the Los Alamos Neutron Science Center at Los Alamos National Laboratory where charged particles and neutrons are produced at energies similar to those found in the space radiation environment. The work presented in this paper constitutes the beginning phase of an undergraduate research project created to contribute to this ongoing space radiation shielding project. Specifically, this student project entails devel-oping and maintaining a database of information concerning the historical data from shielding experiments along with a systematic categorization and storage system for the actual shielding materials. The shielding materials referred to here range in composition from standard materi-als such as high density polyethylene and aluminum to exotic multifunctional materials such as spectra-fiber infused composites. The categorization process for each material includes deter-mination of the density thickness of individual

  13. Electron-scale measurements of magnetic reconnection in space.

    PubMed

    Burch, J L; Torbert, R B; Phan, T D; Chen, L-J; Moore, T E; Ergun, R E; Eastwood, J P; Gershman, D J; Cassak, P A; Argall, M R; Wang, S; Hesse, M; Pollock, C J; Giles, B L; Nakamura, R; Mauk, B H; Fuselier, S A; Russell, C T; Strangeway, R J; Drake, J F; Shay, M A; Khotyaintsev, Yu V; Lindqvist, P-A; Marklund, G; Wilder, F D; Young, D T; Torkar, K; Goldstein, J; Dorelli, J C; Avanov, L A; Oka, M; Baker, D N; Jaynes, A N; Goodrich, K A; Cohen, I J; Turner, D L; Fennell, J F; Blake, J B; Clemmons, J; Goldman, M; Newman, D; Petrinec, S M; Trattner, K J; Lavraud, B; Reiff, P H; Baumjohann, W; Magnes, W; Steller, M; Lewis, W; Saito, Y; Coffey, V; Chandler, M

    2016-06-01

    Magnetic reconnection is a fundamental physical process in plasmas whereby stored magnetic energy is converted into heat and kinetic energy of charged particles. Reconnection occurs in many astrophysical plasma environments and in laboratory plasmas. Using measurements with very high time resolution, NASA's Magnetospheric Multiscale (MMS) mission has found direct evidence for electron demagnetization and acceleration at sites along the sunward boundary of Earth's magnetosphere where the interplanetary magnetic field reconnects with the terrestrial magnetic field. We have (i) observed the conversion of magnetic energy to particle energy; (ii) measured the electric field and current, which together cause the dissipation of magnetic energy; and (iii) identified the electron population that carries the current as a result of demagnetization and acceleration within the reconnection diffusion/dissipation region. PMID:27174677

  14. Atmospheric environment for space shuttle (STS-13) launch

    NASA Technical Reports Server (NTRS)

    Johnson, D. L.; Hill, C. K.; Jasper, G.; Batts, G. W.

    1984-01-01

    Selected atmospheric conditions observed near Space Shuttle STS-13 launch time on April 6, 1984, at Kennedy Space Center Florida are summarized. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere measured vertical wind profiles is given. The final meteorological tape, which consists of wind and thermodynamic parameters versus altitude, for STS-13 vehicle ascent was constructed by Marshall Space Flight Center in response to shuttle task agreement No. 561-81-22-368 with Johnson Space Center.

  15. Atmospheric environment for Space Shuttle (STS-9) launch

    NASA Technical Reports Server (NTRS)

    Johnson, D. L.; Hill, C. K.; Batts, G. W.

    1984-01-01

    This report presents a summary of selected atmospheric conditions observed near Space Shuttle STS-9 launch time on November 28, 1983, at Kennedy Space Center, Florida. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere measured vertical wind profiles is given in this report. The final meteorological tape, which consists of wind and thermodynamic parameters versus altitude, for STS-9 vehicle ascent has been constructed. The STS-9 ascent meteorological data tape has been constructed by Marshall Space Flight Center in response to Shuttle task agreement No. 561-81-22-368 with Johnson Space Center.

  16. Atmospheric environment for Space Shuttle (STS-4) launch

    NASA Technical Reports Server (NTRS)

    Johnson, D. L.; Hill, C. K.; Batts, G. W.

    1982-01-01

    Selected atmospheric conditions observed near space shuttle STS-4 launch time on June 27, 1982, at Kennedy Space Center, Florida are summarized. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere measured vertical wind profiles is given as well as the wind and thermodynamic parameters measured at the surface and aloft in the SRB descent/impact ocean area. Final meteorological tapes, which consist of wind descent were constructed. The STS-4 ascent meteorological data tape was constructed by Marshall Space Flight Center in response to shuttle task agreement No. 989-13-22-368 with Johnson Space Center.

  17. Recent Studies of Space Radiation Environment in Japan Aerospace Exploration Agency

    NASA Astrophysics Data System (ADS)

    Koshiishi, Hideki

    Japan Aerospace Exploration Agency (JAXA) has measured the space radiation environment and its effects on spacecraft and astronaut since 1987. We had developed and operated charged-particle monitors, neutron monitors, magnetometers, dosimeters, single-event monitors, electric-potential monitors, and atomic-oxygen monitors onboard eight spacecrafts, and at present, have operated some of them onboard three GEO satellites and three LEO satellites. The obtained space radiation environment data has been gathered into the Space Environment and Effects System database (SEES, http://sees.tksc.jaxa.jp/), and utilized for short-term forecasts for safety operation of spacecraft and manned space mission, for understandings and evaluations of spacecraft anomalies and astronaut dose, and for long-term static and dynamic space radiation environment modelings for reliable design of future plannings. In this presentation, recent studies of space radiation environment in JAXA will be reported.

  18. Current Activities and Capabilities of the Terrestrial Environment Group at NASA's Marshall Space Flight Center

    NASA Technical Reports Server (NTRS)

    Roberts, Barry C.; Batts, Wade

    1997-01-01

    The National Aeronautics and Space Administration (NASA) designated Marshall Space Flight Center (MSFC) the center of excellence for space transportation. The Aerospace Environments and Effects (AEE) team of the Electromagnetics and Aerospace Environments Branch (EL23) in the Systems Analysis and Integration Laboratory at MSFC, supports the center of excellence designation by providing near-Earth space, deep space, planetary, and terrestrial environments expertise to projects as required. The Terrestrial Environment (TE) group within the AEE team maintains an extensive TE data base. Statistics and models derived from this data are applied to the design and development of new aerospace vehicles, as well as performance enhancement of operational vehicles such as the Space Shuttle. The TE is defined as the Earth's atmospheric environment extending from the surface to orbital insertion altitudes (approximately 90 km).

  19. Amorphous and polycrystalline water ices in space environments

    NASA Astrophysics Data System (ADS)

    Andrade, Diana; Pilling, Sergio; Da Silveira, Enio; Barros, Ana

    2016-07-01

    Ices are an important reservoir of more complex molecular species in several space environments, containing information about the composition and formation of these regions. Water ice is the dominant constituent of interstellar ices in most lines of sight and is about 70 % of the composition in comets, being a key molecule in astrochemical models. It is believed that one of the reactive species possibly evaporated from the water ices is the hydronium ion, H_{3}O^{+}, which plays an important role in the oxygen chemistry network. This ion has been detected in the lunar surface of Enceladus and Titan, and toward the Sagittarius B2 molecular Clouds, where H_{2}O and OH were also identified. In this work, the ion desorption due to radiolysis in ices constituted by water at three different temperatures (40, 70 and 125 K) is studied, to investigate the different allotropic water ices. A discussion on the rate of H_{3}O^{+} and water delivered to gas phase, as well as the half-life of water ice grains, inside dense molecular clouds considering a constants cosmic ray flux is given. The ions desorbed from water ice have been mass/charge analyzed by a time-of-flight spectrometer. Among the results, it is seen that in the positive ion spectrum of high density amorphous water ice at 40 K the highest desorption yields (ejected ions/impact) correspond to H^{+}, H_{3}O^{+} and clusters formed by (H_{2}O)_{n}R^{+}, where R^{+} is H_{3}O^{+} and 1 ≤ n ≤ 25. At T = 125 K, the ice is in its low density polycrystalline form and new clusters are present, such as (H_{2}O)_{n}R^{+}, where R^{+} is H_{2}^{+} and H_{3}^{+} (for low n), beyond H_{3}O^{+}. Therefore, it is seen that (H_{2}O)_{n}H_{3}O^{+} series (with n between 1 and 25) is dominant in all cases. The H_{3}O^{+} desorption yield at 40 K is about 5times10^{-3} ions/impact. This value is 4-5 times higher than the one obtained at T > 125 K. This behavior is also seen to all series member and consequently to the sum (Yn).

  20. Space applications of the MITS electron-photon Monte Carlo transport code system

    SciTech Connect

    Kensek, R.P.; Lorence, L.J.; Halbleib, J.A.; Morel, J.E.

    1996-07-01

    The MITS multigroup/continuous-energy electron-photon Monte Carlo transport code system has matured to the point that it is capable of addressing more realistic three-dimensional adjoint applications. It is first employed to efficiently predict point doses as a function of source energy for simple three-dimensional experimental geometries exposed to simulated uniform isotropic planar sources of monoenergetic electrons up to 4.0 MeV. Results are in very good agreement with experimental data. It is then used to efficiently simulate dose to a detector in a subsystem of a GPS satellite due to its natural electron environment, employing a relatively complex model of the satellite. The capability for survivability analysis of space systems is demonstrated, and results are obtained with and without variance reduction.

  1. In-Flight Manual Electronics Repair for Deep-Space Missions

    NASA Technical Reports Server (NTRS)

    Pettegrew, Richard; Easton, John; Struk, Peter; Anderson, Eric

    2007-01-01

    Severe limitations on mass and volume available for spares on long-duration spaceflight missions will require electronics repair to be conducted at the component level, rather than at the sub-assembly level (referred to as Orbital Replacement Unit, or 'ORU'), as is currently the case aboard the International Space Station. Performing reliable component-level repairs in a reduced gravity environment by crew members will require careful planning, and some specialty tools and systems. Additionally, spacecraft systems must be designed to enable such repairs. This paper is an overview of a NASA project which examines all of these aspects of component level electronic repair. Results of case studies that detail how NASA, the U.S. Navy, and a commercial company currently approach electronics repair are presented, along with results of a trade study examining commercial technologies and solutions which may be used in future applications. Initial design recommendations resulting from these studies are also presented.

  2. Degradation of thermal control materials under a simulated radiative space environment

    NASA Astrophysics Data System (ADS)

    Sharma, A. K.; Sridhara, N.

    2012-11-01

    A spacecraft with a passive thermal control system utilizes various thermal control materials to maintain temperatures within safe operating limits. Materials used for spacecraft applications are exposed to harsh space environments such as ultraviolet (UV) and particle (electron, proton) irradiation and atomic oxygen (AO), undergo physical damage and thermal degradation, which must be considered for spacecraft thermal design optimization and cost effectiveness. This paper describes the effect of synergistic radiation on some of the important thermal control materials to verify the assumptions of beginning-of-life (BOL) and end-of-life (EOL) properties. Studies on the degradation in the optical properties (solar absorptance and infrared emittance) of some important thermal control materials exposed to simulated radiative geostationary space environment are discussed. The current studies are purely related to the influence of radiation on the degradation of the materials; other environmental aspects (e.g., thermal cycling) are not discussed. The thermal control materials investigated herein include different kind of second-surface mirrors, white anodizing, white paints, black paints, multilayer insulation materials, varnish coated aluminized polyimide, germanium coated polyimide, polyether ether ketone (PEEK) and poly tetra fluoro ethylene (PTFE). For this purpose, a test in the constant vacuum was performed reproducing a three year radiative space environment exposure, including ultraviolet and charged particle effects on North/South panels of a geostationary three-axis stabilized spacecraft. Reflectance spectra were measured in situ in the solar range (250-2500 nm) and the corresponding solar absorptance values were calculated. The test methodology and the degradations of the materials are discussed. The most important degradations among the low solar absorptance materials were found in the white paints whereas the rigid optical solar reflectors remained quite

  3. Maximally spaced projection sequencing in electron paramagnetic resonance imaging

    PubMed Central

    Redler, Gage; Epel, Boris; Halpern, Howard J.

    2015-01-01

    Electron paramagnetic resonance imaging (EPRI) provides 3D images of absolute oxygen concentration (pO2) in vivo with excellent spatial and pO2 resolution. When investigating such physiologic parameters in living animals, the situation is inherently dynamic. Improvements in temporal resolution and experimental versatility are necessary to properly study such a system. Uniformly distributed projections result in efficient use of data for image reconstruction. This has dictated current methods such as equal-solid-angle (ESA) spacing of projections. However, acquisition sequencing must still be optimized to achieve uniformity throughout imaging. An object-independent method for uniform acquisition of projections, using the ESA uniform distribution for the final set of projections, is presented. Each successive projection maximizes the distance in the gradient space between itself and prior projections. This maximally spaced projection sequencing (MSPS) method improves image quality for intermediate images reconstructed from incomplete projection sets, enabling useful real-time reconstruction. This method also provides improved experimental versatility, reduced artifacts, and the ability to adjust temporal resolution post factum to best fit the data and its application. The MSPS method in EPRI provides the improvements necessary to more appropriately study a dynamic system. PMID:26185490

  4. Real-space method for highly parallelizable electronic transport calculations

    NASA Astrophysics Data System (ADS)

    Feldman, Baruch; Seideman, Tamar; Hod, Oded; Kronik, Leeor

    2014-07-01

    We present a real-space method for first-principles nanoscale electronic transport calculations. We use the nonequilibrium Green's function method with density functional theory and implement absorbing boundary conditions (ABCs, also known as complex absorbing potentials, or CAPs) to represent the effects of the semi-infinite leads. In real space, the Kohn-Sham Hamiltonian matrix is highly sparse. As a result, the transport problem parallelizes naturally and can scale favorably with system size, enabling the computation of conductance in relatively large molecular junction models. Our use of ABCs circumvents the demanding task of explicitly calculating the leads' self-energies from surface Green's functions, and is expected to be more accurate than the use of the jellium approximation. In addition, we take advantage of the sparsity in real space to solve efficiently for the Green's function over the entire energy range relevant to low-bias transport. We illustrate the advantages of our method with calculations on several challenging test systems and find good agreement with reference calculation results.

  5. Development of multi-functional composite structures with embedded electronics for space application

    NASA Astrophysics Data System (ADS)

    Seong Jang, Tae; Soo Oh, Dae; Kyu Kim, Jin; In Kang, Kyung; Ho Cha, Won; Woo Rhee, Seung

    2011-01-01

    Conventional spacecraft structural function has been limited to supporting loads and mounting avionics only. In contrast, the technology of 'multi-functional structures' can integrate thermal and electronic functions into the spacecraft's inherent load-bearing capability. In addition, sufficient radiation shielding effectiveness can be provided for the anticipated mission environment. Utilizing this concept, the ratio of electrical functionality to spacecraft volume can be dramatically increased and significant mass savings can be obtained. In this paper, spacecraft electronics are miniaturized using advanced IT applications such as flexible circuitry, miniaturized components, featherweight connectors, and so on, that they can be easily embedded within a structural panel. A sandwich structural panel consists of an aluminum honeycomb core and lightweight CFRP facesheets. Integration of electronics is implemented within the panel by mounting electronics on a multi-layered composite enclosure with multi-materials. This composite enclosure provides a load-bearing, effective thermal conduction, radiation shielding capabilities and an available space for embedding electronics. A series of environmental tests and analyses is carried out to demonstrate that the flight hardware is qualified for the expected mission environments. This approach will be utilized for the advanced small satellite 'STSAT-3' to validate the multi-functional structures concept.

  6. Space charge and quantum effects on electron emission

    NASA Astrophysics Data System (ADS)

    Jensen, Kevin L.; Lebowitz, Joel; Lau, Y. Y.; Luginsland, John

    2012-03-01

    Space charge effects reduce electron emission by altering the surface barrier via two effects: increasing the barrier height (Schottky factor) and width to electron emission by lowering the surface field and changing the magnitude of the dipole associated with electron density variation. A one-dimensional emission model using a transit time argument to account for charge in the anode-cathode (AK) gap and an analytical model of the dipole is used to approximate the effects of each factor on the current density. The transit time model is compared to the experimental data of Longo [J. Appl. Phys. 94, 6966 (2003)] for thermal emission. Changes in the dipole contribution are primarily associated with tunneling and therefore field emission. The transit time plus dipole modification is compared to the experimental data of Barbour et al. [Phys. Rev. 92, 45 (1953)] for field emission. The model's application to thermal-field, and photoemission in general is discussed, with the former corresponding to continuous current limit and the latter to a pulsed current limit of the model.

  7. Effects of the space flight environment on the immune system

    NASA Technical Reports Server (NTRS)

    Sonnenfeld, Gerald; Butel, Janet S.; Shearer, William T.

    2003-01-01

    Space flight conditions have a dramatic effect on a variety of physiologic functions of mammals, including muscle, bone, and neurovestibular function. Among the physiological functions that are affected when humans or animals are exposed to space flight conditions is the immune response. The focus of this review is on the function of the immune system in space flight conditions during actual space flights, as well as in models of space flight conditions on the earth. The experiments were carried out in tissue culture systems, in animal models, and in human subjects. The results indicate that space flight conditions alter cell-mediated immune responses, including lymphocyte proliferation and subset distribution, and cytokine production. The mechanism(s) of space flight-induced alterations in immune system function remain(s) to be established. It is likely, however, that multiple factors, including microgravity, stress, neuroendocrine factors, sleep disruption, and nutritional factors, are involved in altering certain functions of the immune system. Such alterations could lead to compromised defenses against infections and tumors.

  8. Atmospheric environment for space shuttle (STS-51B) launch

    NASA Technical Reports Server (NTRS)

    Jasper, G. L.; Johnson, D. L.; Hill, C. K.; Batts, G. W.

    1985-01-01

    A summary of selected atmospheric conditions observed near space shuttle STS-51B launch time on April 29, 1985, at Kennedy Space Center Florida is presented. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere measured vertical wind profiles is given. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-51B vehicle ascent was constructed. The STS-51B ascent atmospheric data tape was constructed by Marshall Space Flight Center's Atmospheric Sciences Division to provide an internally consistent data set for use in post flight performance assessments.

  9. Atmospheric environment for space shuttle (STS-26) launch

    NASA Technical Reports Server (NTRS)

    Jasper, G. L.; Johnson, D. L.; Batts, G. W.

    1989-01-01

    A summary of selected atmospheric conditions observed near Space Shuttle STS-26 launch time on September 29, 1988, at Kennedy Space Center, Florida is given. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of pre-launch Jimsphere measured vertical wind profiles is given. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-26 vehicle ascent has been constructed. The STS-26 ascent atmospheric data tape has been constructed by Marshall Space Flight Center's Earth Science and Applications Division to provide an internally consistent data set for use in post-flight performance assessments.

  10. Atmospheric environment for Space Shuttle (STS-51D)

    NASA Technical Reports Server (NTRS)

    Jasper, G. L.; Johnson, D. L.; Hill, C. K.; Batts, G. W.

    1985-01-01

    A summary of selected atmospheric conditions observed near the space shuttle STS-51D launch time on April 12, 1985, at Kennedy Space Center Florida is presented. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere measured vertical wind profiles is given in this report. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-51D vehicle ascent is constructed. The STS-51D ascent atmospheric data tape is compiled by Marshall Space Flight Center's Atmospheric Sciences Division to provide an internally consistent data set for use in post-flight performance assessments.

  11. Atmospheric environment for space shuttle (STS-51L) launch

    NASA Technical Reports Server (NTRS)

    Jasper, G. L.; Johnson, D. L.; Alexander, M.; Fichtl, G. H.; Batts, G. W.

    1986-01-01

    A summary is given of selected atmospheric conditions observed near Space Shuttle STS-51L launch time on January 28, 1986, at Kennedy Space Center, Florida. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of pre-launch Jimsphere measured vertical wind profiles is given. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-51L vehicle ascent has been constructed. The STS-51L ascent atmospheric data tape has been constructed by Marshall Space Flight Center's Atmospheric Sciences Division to provide an internally consistent data set for use in post flight performance assessments.

  12. Surface analyses of composites exposed to the space environment on LDEF

    NASA Technical Reports Server (NTRS)

    Mallon, Joseph J.; Uht, Joseph C.; Hemminger, Carol S.

    1993-01-01

    A series of surface analyses on carbon fiber/poly(arylacetylene) (PAA) matrix composites that were exposed to the space environment on the Long Duration Exposure Facility (LDEF) satellite were conducted. These composite panels were arranged in pairs on both the leading edge and trailing edge of LDEF. None of the composites were catastrophically damaged by nearly six years of exposure to the space environment. Composites on the leading edge exhibited from 25 to 125 microns of surface erosion, but trailing edge panels exhibited no physical appearance changes due to exposure. Scanning electron microscopy (SEM) was used to show that the erosion morphology on the leading edge samples was dominated by crevasses parallel to the fibers with triangular cross sections 10 to 100 microns in depth. The edges of the crevasses were well defined and penetrated through both matrix and fiber. The data suggest that the carbon fibers are playing an important role in crevasse initiation and/or enlargement, and in the overall erosion rate of the composite. X-ray photoelectron spectroscopy (XPS) and energy dispersive x-ray spectroscopy (EDS) results showed contamination from in-flight sources of silicone.

  13. NASA's Space Environments and Effects (SEE) Program: Meteoroid and Orbital Debris Lesson Plan.

    ERIC Educational Resources Information Center

    National Aeronautics and Space Administration, Washington, DC.

    The study of the natural space environment and its effects on spacecraft is one of the most important and least understood aspects of spacecraft design. The Space Environments and Effects (SEE) Program prepared the Meteoroids and Orbital Debris Lesson Plan, a SEE-focused high school curriculum to engage students in creative activities that will…

  14. Students, Structures, Spaces: Activities in the Built Environment.

    ERIC Educational Resources Information Center

    Eriksen, Aase; Wintermute, Marjorie

    Built environment education, an innovative concept, is not a new subject in educational curricula, but rather an approach to traditional areas of study that can be integrated into existing curricula. The goals of built environment education as outlined and developed in this teachers guide are to develop an awareness of surroundings, senses,…

  15. Networked Environments that Create Hybrid Spaces for Learning Science

    ERIC Educational Resources Information Center

    Otrel-Cass, Kathrin; Khoo, Elaine; Cowie, Bronwen

    2014-01-01

    Networked learning environments that embed the essence of the Community of Inquiry (CoI) framework utilise pedagogies that encourage dialogic practices. This can be of significance for classroom teaching across all curriculum areas. In science education, networked environments are thought to support student investigations of scientific problems,…

  16. Results of space environment measurement carried out by the Roscosmos monitoring system elements and their correlation with different space weather characteristics

    NASA Astrophysics Data System (ADS)

    Protopopov, Grigory; Anashin, Vasily; Elushov, Ilya; Kozyukova, Olga

    The Monitoring System of space radiation exposure on electronic components is developed by the Institute of Space Device Engineering by order Roscosmos. The key targets of the Monitoring System are space environment measurements, space model correction, space weather characteristics forecast, improvement of radiation hardness technical requirements and etc. The Monitoring System includes two parts: the ground-based and the space-born segments. The ground-based segment includes the forecast station, the analytic complex and the data output system. The space-born segment base elements are TID sensors operating by MNOSFET dosimetry principle. Sensor temperature stabilization is achieved by choosing of operational point according to the minimal change of sensor current-voltage curve. The set of 38 TID sensors is placed on 19 spacecrafts currently. The spacecrafts operate in Medium Earth Orbit (MEO) (approximately 20 000 km with inclination of 65(°) ). The flight data obtained perfectly correlate with total dose flight data registered using MOSFET placed on Van Allen Probe spacecraft functioning in high elliptical orbit (apogee is 37 000 km, perigee is 650 km, inclination is 10(°) ). Also coincidence with the dose data from GIOVE-B spacecraft (circular orbit 23200 km, inclination of 56(°) ) of Galileo system is observed. We have observed several abrupt dose rate increases from April, 2010. The flight data are compared with other monitoring system data and ground measurements. The comparison results show that high energy electrons (> 1 MeV) give general contribution in accumulated dose and anomalous dose rate increases. These results are in agreement with shielding stopping power calculation results. The high electron fluxes rise significantly in MEO as a result of Van Allen belts shifting during geomagnetic storms. The flight data were compared with calculation results obtained using different space models. The comparison shows that for some long-term interval the

  17. Cyber warfare and electronic warfare integration in the operational environment of the future: cyber electronic warfare

    NASA Astrophysics Data System (ADS)

    Askin, Osman; Irmak, Riza; Avsever, Mustafa

    2015-05-01

    For the states with advanced technology, effective use of electronic warfare and cyber warfare will be the main determining factor of winning a war in the future's operational environment. The developed states will be able to finalize the struggles they have entered with a minimum of human casualties and minimum cost thanks to high-tech. Considering the increasing number of world economic problems, the development of human rights and humanitarian law it is easy to understand the importance of minimum cost and minimum loss of human. In this paper, cyber warfare and electronic warfare concepts are examined in conjunction with the historical development and the relationship between them is explained. Finally, assessments were carried out about the use of cyber electronic warfare in the coming years.

  18. Nonlinear Potential Model of Space-Charge Electron Beams

    NASA Astrophysics Data System (ADS)

    Litz, Marc Stuart

    1995-01-01

    This body of work is new and comprises theoretical analysis, numerical simulation and experimental investigations of the vircator, a tunable, compact, simply constructed, high power reflexing electron device that is used as a microwave source. A 1D theoretical model is formulated that is based on a time-varying, nonlinear potential to better understand the sensitivities of individual electron trajectories to macroscopic parameters of the system. Self -consistent 2D (space) and 3D(velocity) numerical PIC simulations are used to find common dynamical behavior that links the individual test-particle trajectories examined in the 1D nonlinear model with the experimental measurements of the final state of the electron trajectories. The experiment designed and built for these studies is unique and contrasts with other virtual cathode electron beam sources because it operates at lower voltage, and longer pulse width than previous forms of the device. The anode-cathode (AK) gap spacing is externally tunable expediting parametric studies. In addition, it is repetitively pulsed, which permits discrimination between single-shot anomalies and repeatable variation that often occurs in pulsed power experimental devices. These attributes distinguish this experimental apparatus from previous experimental platforms. This novel, repetitively pulsed device has particular relevance to the industrial and medical applications of rf. The approach followed in the present studies is (1) to investigate the dynamic behavior of individual test -particles in a simplified 1D, nonlinear, time-varying, potential; (2) utilize a 2D, self-consistent, electromagnetic PIC code to generate single particle trajectories subject to the collective effects of the electron beam; and (3) measure macroscopic quantities of voltage, current, electromagnetic fields, and electron flux in an experimental platform. Results of the 3D experiments are compared to predictions of the 1D and 2D models. Electron flux

  19. Atmospheric environment for Space Shuttle (STS-6) launch

    NASA Technical Reports Server (NTRS)

    Johnson, D. L.; Hill, C. K.; Batts, G. W.

    1983-01-01

    Selected atmospheric conditions observed near Space Shuttle STS-6 launch time on April 4, 1983, at Kennedy Space Center, Florida are summarized. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere measured vertical wind profiles is given. Also presented are the wind and thermodynamic parameters measured at the surface and aloft in the SRB descent/impact ocean area. Final meteorological tapes, which consist of wind and thermodynamic parameters versus altitude, for STS-6 veicle ascent and SRB descent were constructed. The STS-6 ascent meteorological data tape was constructed by Marshall Space Flight Center in response to Shuttle task agreement No. 936-53-22-368 with Johnson Space Center.

  20. Study made of explosive cutting in simulated space environments

    NASA Technical Reports Server (NTRS)

    Coleman, E. R.; Hamilton, L. O.

    1967-01-01

    Study indicates the feasibility of explosive cutting and establishes techniques applicable to in-space cutting operations. Results show no degradation of the explosive and that work hardening of the target material is limited to the cut edge.

  1. Atmospheric environment for Space Shuttle (STS-7) launch

    NASA Technical Reports Server (NTRS)

    Johnson, D. L.; Hill, C. K.; Batts, G. W.

    1983-01-01

    Selected atmospheric conditions observed near Space Shuttle STS-7 launch time on June 18, 1983, at Kennedy Space Center, Florida are summarized. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere measured vertical wind profiles is given in this report. Also presented are wind and thermodynamic parameters representative of surface and aloft conditions in the SRB descent/impact ocean area. Final meteorological tapes, which consist of wind and thermodynamic parameters versus altitude, for STS-7 vehicle ascent and Acoustic/SRB descent have been constructed. The STS-7 ascent meteorological data tape has been constructed by Marshall Space Flight Center in response to Shuttle task agreement No. 936-53-22-368 with Johnson Space Center.

  2. Bulk Charging of Dielectrics in Cryogenic Space Environments

    NASA Technical Reports Server (NTRS)

    Minow, J. I.; Coffey, V. N.; Blackwell, W. C., Jr.; Parker, L. N.; Jun, I.; Garrett, H. B.

    2007-01-01

    We use a 1-D bulk charging model to evaluate dielectric charging at cryogenic temperatures relevant to space systems using passive cooling to <100K or extended operations in permanently dark lunar craters and the lunar night.

  3. Atmospheric environment for Space Shuttle (STS-5) launch

    NASA Technical Reports Server (NTRS)

    Johnson, D. L.; Hill, C. K.; Batts, G. W.

    1983-01-01

    This report presents a summary of selected atmospheric conditions observed near Space Shuttle STS-5 launch time on November 11, 1982, at Kennedy Space Center, Florida. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere measured vertical wind profiles is given in this report. Also presented are the wind and thermodynamic parameters measured at the surface and aloft in he SRB descent/impact ocean area. Final meteorological tapes, which consist of wind and thermodynamic parameters versus altitude, for STS-5 vehicle ascent and SRB descent have been constructed. The STS-5 ascent meteorological data tape has been constructed by Marshall Space Flight Center in response to Shuttle task agreement No. 936-53-22-368 with Johnson Space Center.

  4. Radiation effects control: Eyes, skin. [space environment simulation

    NASA Technical Reports Server (NTRS)

    Hightower, D.; Smathers, J. B.

    1974-01-01

    Adverse effects on the lens of the eye and the skin due to exposure to proton radiation during manned space flight were evaluated. Actual proton irradiation which might be encountered in space was simulated. Irradiation regimes included single acute exposures, daily fractionated exposures, and weekly fractionated exposures. Animals were exposed and then maintained and examined periodically until data sufficient to meet the objective were obtained. No significant skin effects were noted and no serious sight impairment was exhibited.

  5. Reconfiguration of Analog Electronics for Extreme Environments: Problem or Solution?

    NASA Technical Reports Server (NTRS)

    Stoica, Adrian; Zebulum, Ricardo; Keymeulen, Didier; Guo, Xin

    2005-01-01

    This paper argues in favor of adaptive reconfiguration as a technique to expand the operational envelope of analog electronics for extreme environments (EE). In addition to hardening-by-process and hardening-by-design, "hardening-by-reconfiguration", when applicable, could be used to mitigate drifts, degradation, or damage on electronic devices (chips) in EE, by using re-configurable devices and an adaptive self-reconfiguration of their circuit topology. Conventional circuit design exploits device characteristics within a certain temperature/radiation range; when that is exceeded, the circuit function degrades. On a reconfigurable device, although component parameters change in EE, as long as devices still operate, albeit degraded, a new circuit design, suitable for new parameter values, may be mapped into the reconfigurable structure to recover the initial circuit function. Partly degraded resources are still used, while completely damaged resources are bypassed. Designs suitable for various environmental conditions can be determined prior to operation or can be determined in-situ, by adaptive reconfiguration algorithms running on built-in digital controllers. Laboratory demonstrations of this technique were performed by JPL in several independent experiments in which bulk CMOS reconfigurable devices were exposed to, and degraded by, low temperatures (approx. 196 C), high temperatures (approx.300 C) or radiation (300kRad TID), and then recovered by adaptive reconfiguration using evolutionary search algorithms. Taking this technology from Technology Readiness Level (TRL) 3 to TRL 5 is the target of a current NASA project.

  6. Using Space Weather Variability in Evaluating the Radiation Environment Design Specifications for NASA's Constellation Program

    NASA Technical Reports Server (NTRS)

    Coffey, Victoria N.; Blackwell, William C.; Minow, Joseph I.; Bruce, Margaret B.; Howard, James W.

    2007-01-01

    NASA's Constellation program, initiated to fulfill the Vision for Space Exploration, will create a new generation of vehicles for servicing low Earth orbit, the Moon, and beyond. Space radiation specifications for space system hardware are necessarily conservative to assure system robustness for a wide range of space environments. Spectral models of solar particle events and trapped radiation belt environments are used to develop the design requirements for estimating total ionizing radiation dose, displacement damage, and single event effects for Constellation hardware. We first describe the rationale using the spectra chosen to establish the total dose and single event design environmental specifications for Constellation systems. We then compare variability of the space environment to the spectral design models to evaluate their applicability as conservative design environments and potential vulnerabilities to extreme space weather events

  7. Evaluation of reformulated thermal control coatings in a simulated space environment. Part 1: YB-71

    NASA Technical Reports Server (NTRS)

    Cerbus, Clifford A.; Carlin, Patrick S.

    1994-01-01

    The Air Force Space and Missile Systems Center and Wright Laboratory Materials Directorate (WL/ML) have sponsored and effort to effort to reformulate and qualify Illinois Institute of Technology Research Institute (IITRI) spacecraft thermal control coatings. S13G/LO-1, Z93, and YB-71 coatings were reformulated because the potassium silicate binder, Sylvania PS-7, used in the coatings is no longer manufactured. Coatings utilizing the binder's replacement candidate, Kasil 2130, manufactured by The Philadelphia Quartz (PQ) Corporation, Baltimore, Maryland, and undergoing testing at the Materials Directorate's Space Combined Effects Primary Test and Research Equipment (SCEPTRE) Facility operated by the University of Dayton Research Institute (UDRI). The simulated space environment consists of combined ultraviolet (UV) and electron exposure with in site specimen reflectance measurements. A brief description of the effort at IITRI, results and discussion from testing the reformulated YB-71 coating in SCEPTRE, and plans for further testing of reformulated Z93 and S13G/LO-1 are presented.

  8. Enhancement of surface durability of space materials and structures in LEO environment

    NASA Astrophysics Data System (ADS)

    Gudimenko, Y.; Ng, R.; Kleiman, J. I.; Iskanderova, Z. A.; Tennyson, R. C.; Hughes, P. C.; Milligan, D.; Grigorevski, A.; Shuiski, M.; Kiseleva, L.; Edwards, D.; Finckenor, M.

    2003-09-01

    Results of on-going program that involves surface modification treatments of thin polymer films and various organic-based thermal control coatings by an innovative Photosil surface modification technology for space durability improvement are presented, as well as results of ground-based testing in an oxygen plasma asher and in fast atomic oxygen (FAO) beam facility. In addition, independent ground-based FAO + VUV test results from NASA Marshall Space Flight Center (MSFC) are also presented. Recent results are presented to further improve the AO durability of conductive thermal control paints, never previously treated by the Photosil process. The thermal control coatings evaluated in this program represent existing commercially available space-approved materials and experimental coatings, which are still under development. Functional properties and performance characteristics, such as AO stability, thermal optical properties, surface resistivity, and outgassing characteristics of pristine and treated materials were also verified. FAO+VUV exposure tests results revealed that some of the successfully treated materials did not show any mass loss or surface morphology change, thus indicating good protection from the severe oxidative environment. A few complementary surface analysis techniques, such as X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS) have been used to examine the composition and structure of the protective surface-modified layer.

  9. Evaluation of piezoelectric PVDF polymers for use in space environments.

    SciTech Connect

    Dargaville, Tim Richard; Assink, Roger Alan; Celina, Mathias Christopher; Chaplya, Pavel Mikhail

    2003-07-01

    Thin polymer films have been identified as one of the major enabling technologies for future space-based systems. Potential devices include those based on piezoelectric bimorph polymers that deform when a charge is deposited, for example, from an electron gun. The thin-film and lightweight nature of the polymeric devices will allow them to be launched more readily and deployed to operating conditions once in orbit. Until now little work has been done aimed at investigating the performance of piezoelectric properties of PVDF and its copolymers and the prediction of their long-term stability in low Earth orbit (LEO) environmental conditions. In this paper, the piezoelectric properties of PVDF and the copolymers formed from polymerization of vinylidene fluoride and trifluoroethylene (TrFE) or hexafluoropropylene (HFP) have been studied over a broad temperature range simulating that expected in LEO. The temperatures experienced by unprotected polymers on low altitude spacecraft have previously been reported as ranging from approximately -100 C to +130 C as the polymer/spacecraft passes in and out of the Earth's shadow. To examine the effects of temperature on the piezoelectric properties of poled PVDF, P(VDF-TrFE) and P(VDF-HFP) the d{sub 33} piezoelectric coefficients and electric displacement-electric field (D-E) hysteresis loops were measured up to 160 C for the d{sub 33} measurements and from -80 to +110 C for the D-E loops. The room temperature d{sub 33} coefficient of PVDF homopolymer films, annealed for extended periods at 50, 80 and 125 C, dropped rapidly within a few days of heating, then remained unchanged for periods of up to 300 days. In contrast, the TrFE copolymer exhibited greater thermal stability than the homopolymer, with the d{sub 33} remaining almost unchanged from the pre-annealing value after heating at 50, 80 and 125 C. The HFP copolymer exhibited poor retention of d33 at temperatures above 80 C. For all three polymers short term annealing at 160

  10. Results from the Space Shuttle STS-95 Electronic Nose Experiment

    NASA Technical Reports Server (NTRS)

    Ryan, M. A.; Buehler, M. G.; Homer, M. L.; Mannatt, K. S.; Lau, B.; Jackson, S.; Zhou, H.

    2000-01-01

    A miniature electronic nose in which the sensing media are insulating polymers loaded with carbon black as a conductive medium has been designed and built at the Jet Propulsion Laboratory. The ENose has a volume of 1700 cc, weighs 1.4 kg including the operating computer, and uses 1.5 W average power (3 W peak power). This ENose was used in a demonstration experiment aboard STS-95 (October, 1998), in which the ENose was operated continuously for six days and recorded the sensors' response to the air in the middeck. The ENose was designed to detect ten common contaminants in space shuttle crew quarters air. The experiment was controlled by collecting air samples daily and analyzing them using standard analytical techniques after the flight. Changes in humidity were detected and quantified, neither the ENose nor the air samples detected any of the contaminants on the target list. The device is microgravity insensitive.

  11. Nanoscale Engineering of Closely-Spaced Electronic Spins in Diamond.

    PubMed

    Scarabelli, Diego; Trusheim, Matt; Gaathon, Ophir; Englund, Dirk; Wind, Shalom J

    2016-08-10

    Numerous theoretical protocols have been developed for quantum information processing with dipole-coupled solid-state spins. Nitrogen vacancy (NV) centers in diamond have many of the desired properties, but a central challenge has been the positioning of NV centers at the nanometer scale that would allow for efficient and consistent dipolar couplings. Here we demonstrate a method for chip-scale fabrication of arrays of single NV centers with record spatial localization of about 10 nm in all three dimensions and controllable inter-NV spacing as small as 40 nm, which approaches the length scale of strong dipolar coupling. Our approach uses masked implantation of nitrogen through nanoapertures in a thin gold film, patterned via electron-beam lithography and dry etching. We verified the position and spin properties of the resulting NVs through wide-field super-resolution optically detected magnetic resonance imaging. PMID:27428077

  12. Mutations of photosystem II D1 protein that empower efficient phenotypes of Chlamydomonas reinhardtii under extreme environment in space.

    PubMed

    Giardi, Maria Teresa; Rea, Giuseppina; Lambreva, Maya D; Antonacci, Amina; Pastorelli, Sandro; Bertalan, Ivo; Johanningmeier, Udo; Mattoo, Autar K

    2013-01-01

    Space missions have enabled testing how microorganisms, animals and plants respond to extra-terrestrial, complex and hazardous environment in space. Photosynthetic organisms are thought to be relatively more prone to microgravity, weak magnetic field and cosmic radiation because oxygenic photosynthesis is intimately associated with capture and conversion of light energy into chemical energy, a process that has adapted to relatively less complex and contained environment on Earth. To study the direct effect of the space environment on the fundamental process of photosynthesis, we sent into low Earth orbit space engineered and mutated strains of the unicellular green alga, Chlamydomonas reinhardtii, which has been widely used as a model of photosynthetic organisms. The algal mutants contained specific amino acid substitutions in the functionally important regions of the pivotal Photosystem II (PSII) reaction centre D1 protein near the QB binding pocket and in the environment surrounding Tyr-161 (YZ) electron acceptor of the oxygen-evolving complex. Using real-time measurements of PSII photochemistry, here we show that during the space flight while the control strain and two D1 mutants (A250L and V160A) were inefficient in carrying out PSII activity, two other D1 mutants, I163N and A251C, performed efficient photosynthesis, and actively re-grew upon return to Earth. Mimicking the neutron irradiation component of cosmic rays on Earth yielded similar results. Experiments with I163N and A251C D1 mutants performed on ground showed that they are better able to modulate PSII excitation pressure and have higher capacity to reoxidize the QA (-) state of the primary electron acceptor. These results highlight the contribution of D1 conformation in relation to photosynthesis and oxygen production in space. PMID:23691201

  13. Mutations of Photosystem II D1 Protein That Empower Efficient Phenotypes of Chlamydomonas reinhardtii under Extreme Environment in Space

    PubMed Central

    Lambreva, Maya D.; Antonacci, Amina; Pastorelli, Sandro; Bertalan, Ivo; Johanningmeier, Udo; Mattoo, Autar K.

    2013-01-01

    Space missions have enabled testing how microorganisms, animals and plants respond to extra-terrestrial, complex and hazardous environment in space. Photosynthetic organisms are thought to be relatively more prone to microgravity, weak magnetic field and cosmic radiation because oxygenic photosynthesis is intimately associated with capture and conversion of light energy into chemical energy, a process that has adapted to relatively less complex and contained environment on Earth. To study the direct effect of the space environment on the fundamental process of photosynthesis, we sent into low Earth orbit space engineered and mutated strains of the unicellular green alga, Chlamydomonas reinhardtii, which has been widely used as a model of photosynthetic organisms. The algal mutants contained specific amino acid substitutions in the functionally important regions of the pivotal Photosystem II (PSII) reaction centre D1 protein near the QB binding pocket and in the environment surrounding Tyr-161 (YZ) electron acceptor of the oxygen-evolving complex. Using real-time measurements of PSII photochemistry, here we show that during the space flight while the control strain and two D1 mutants (A250L and V160A) were inefficient in carrying out PSII activity, two other D1 mutants, I163N and A251C, performed efficient photosynthesis, and actively re-grew upon return to Earth. Mimicking the neutron irradiation component of cosmic rays on Earth yielded similar results. Experiments with I163N and A251C D1 mutants performed on ground showed that they are better able to modulate PSII excitation pressure and have higher capacity to reoxidize the QA− state of the primary electron acceptor. These results highlight the contribution of D1 conformation in relation to photosynthesis and oxygen production in space. PMID:23691201

  14. RELEC Experiment on board Vernov Satellite: Relativistic Electron Flux Dynamics in Near-Earth Space

    NASA Astrophysics Data System (ADS)

    Svertilov, Sergiey

    2015-04-01

    The main goal of RELEC mission is study of magnetosphere relativistic electron precipitation with it possible acting on the upper atmosphere and ionosphere as well as the monitor observation of radiation and electromagnetic environment in the near-Earth Space. The RELEC set of instruments includes two identical detectors of X- and gamma-rays of high temporal resolution and sensitivity (DRGE-1 & DRGE-2), three axe directed detectors of energetic electrons and protons DRGE-3, UV TLE imager MTEL, UV detector DUV, low-frequency analyser LFA, radio-frequency analyser RFA, module of electronics intended for commands and data collection BE. The small satellite now named Vernov with RELEC instruments was successfully launched July, 8 2014. The mission orbit is solar-synchronous with apogee 830 km, perigee 640 km, inclination 98.4o and orbital period about 100 min. The total data output is about 1.2 Gbyte per day. The fluxes and spectra of electrons in the wide energy range from 0.2 to 15 MeV are measured with the use of three detectors with axe normally directed to each other: to the local zenith, opposite to the satellite velocity vector and along the direction added two previous to the Cartesian system. Due to such detector system it is possible to estimate the electron flux anisotropy. The wide dynamical range from ~1 up to 104 part/cm2s and fine time resolution (~10 mcs) allows observations of trapped, quasi-trapped and precipitated electron flux and spectral variations in different areas in the near-Earth space including low L-shells. Comparative analysis of electron fluxes measured by RELEC with experimental data on electron detection in the experiments on board the spacecraft Electro-L with geostationary orbit, and Meteor-M2 with 800 km altitude circular polar orbit similar to Vernov allows to reconstruct the energetic electron spatial distribution in the near-Earth space. A comparison will be held for periods of moderate geomagnetic disturbances of August 26

  15. Dust environment of an airless object: A phase space study with kinetic models

    NASA Astrophysics Data System (ADS)

    Kallio, E.; Dyadechkin, S.; Fatemi, S.; Holmström, M.; Futaana, Y.; Wurz, P.; Fernandes, V. A.; Álvarez, F.; Heilimo, J.; Jarvinen, R.; Schmidt, W.; Harri, A.-M.; Barabash, S.; Mäkelä, J.; Porjo, N.; Alho, M.

    2016-01-01

    The study of dust above the lunar surface is important for both science and technology. Dust particles are electrically charged due to impact of the solar radiation and the solar wind plasma and, therefore, they affect the plasma above the lunar surface. Dust is also a health hazard for crewed missions because micron and sub-micron sized dust particles can be toxic and harmful to the human body. Dust also causes malfunctions in mechanical devices and is therefore a risk for spacecraft and instruments on the lunar surface. Properties of dust particles above the lunar surface are not fully known. However, it can be stated that their large surface area to volume ratio due to their irregular shape, broken chemical bonds on the surface of each dust particle, together with the reduced lunar environment cause the dust particles to be chemically very reactive. One critical unknown factor is the electric field and the electric potential near the lunar surface. We have developed a modelling suite, Dusty Plasma Environments: near-surface characterisation and Modelling (DPEM), to study globally and locally dust environments of the Moon and other airless bodies. The DPEM model combines three independent kinetic models: (1) a 3D hybrid model, where ions are modelled as particles and electrons are modelled as a charged neutralising fluid, (2) a 2D electrostatic Particle-in-Cell (PIC) model where both ions and electrons are treated as particles, and (3) a 3D Monte Carlo (MC) model where dust particles are modelled as test particles. The three models are linked to each other unidirectionally; the hybrid model provides upstream plasma parameters to be used as boundary conditions for the PIC model which generates the surface potential for the MC model. We have used the DPEM model to study properties of dust particles injected from the surface of airless objects such as the Moon, the Martian moon Phobos and the asteroid RQ36. We have performed a (v0, m/q)-phase space study where the

  16. The Apollo 16 microbial response to space environment experiment

    NASA Technical Reports Server (NTRS)

    Taylor, G. R.

    1975-01-01

    The effect was evaluated of a particular space flight on the survival rate of nine different species. Although a reasonable variety of organisms (viruses, yeasts, filamentous fungi, bacteria, and an invertebrate) were tested under several different conditions, no statistically valid differences could be detected in the survival of flight samples when compared to corresponding ground-based controls. In general, these evaluations were based on multiple observations of from ten to thirty replicates of up to one million cells each. While the results conflict with those of certain other space flight investigations, it is observed that the conditions of a particular space flight cannot be exactly duplicated, and therefore results from different flights are not directly comparable.

  17. Radiation environment study of near space in China area

    NASA Astrophysics Data System (ADS)

    Fan, Dongdong; Chen, Xingfeng; Li, Zhengqiang; Mei, Xiaodong

    2015-10-01

    Aerospace activity becomes research hotspot for worldwide aviation big countries. Solar radiation study is the prerequisite for aerospace activity to carry out, but lack of observation in near space layer becomes the barrier. Based on reanalysis data, input key parameters are determined and simulation experiments are tried separately to simulate downward solar radiation and ultraviolet radiation transfer process of near space in China area. Results show that atmospheric influence on the solar radiation and ultraviolet radiation transfer process has regional characteristic. As key factors such as ozone are affected by atmospheric action both on its density, horizontal and vertical distribution, meteorological data of stratosphere needs to been considered and near space in China area is divided by its activity feature. Simulated results show that solar and ultraviolet radiation is time, latitude and ozone density-variant and has complicated variation characteristics.

  18. Atmospheric environment for space shuttle (STS-30) launch

    NASA Technical Reports Server (NTRS)

    Jasper, G. L.; Batts, G. W.

    1989-01-01

    This report presents a summary of selected atmospheric conditions observed near Space Shuttle STS-30 launch time on May 4, 1989, at Kennedy Space Center, Florida. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of pre-launch Jimsphere-measured vertical wind profiles is given in this report. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-30 vehicle ascent has been constructed. The STS-30 ascent atmospheric data tape has been constructed by Marshall Space Flight Center's Earth Science and Applications Division to provide an internally consistent data set for use in post-flight performance assessments.

  19. Atmospheric environment for Space Shuttle (STS-41G) launch

    NASA Technical Reports Server (NTRS)

    Johnson, D. L.; Hill, C. K.; Jasper, G.; Batts, G. W.

    1984-01-01

    Selected atmospheric conditions that were observed near Space Shuttle STS-41G launch time on October 5, 1984 at Kennedy Space Center in Florida are summarized. Values of ambient pressure, temperature, moisture, ground winds, visual obsrvations (cloud), and winds aloft are included. The sequence of prelaunch Jimsphere-measured vertical wind profiles is given. The final atmospheric tape consisting of wind and thermodynamic parameters versus altitude for STS-41G vehicle ascent was constructed. The STS-41G ascent atmospheric data tape was constructed. The STS-41G ascent atmospheric data tape was constructed by Marshall Space Flight Center's Atmospheric Sciences Division to provide an internally consistent data set for use in post flight performance assessments.

  20. Atmospheric environment for Space Shuttle (STS-27) launch

    NASA Technical Reports Server (NTRS)

    Jasper, G. L.; Johnson, D. L.; Batts, G. W.

    1989-01-01

    Selected articles on atmospheric conditions observed near Space Shuttle STS-27 launch time on December 2, 1988, at Kennedy Space Center, Florida are summarized. STS-27 carried a Department of Defense payload and the flight azimuth in this report will be denoted by reference flight azimuth, since the actual flight azimuth is not known. Values of ambient pressure, temperature, moisture, ground winds, visual observations (cloud), and winds aloft are included. The sequence of pre-launch Jimsphere-measured vertical wind profiles is given. The final atmospheric tape, which consists of wind and thermodynamic parameters versus altitude, for STS-27 vehicle ascent was constructed. The STS-27 ascent atmospheric data tape was constructed by Marshall Space Flight Center's Earth Science and Applications Division to provide an internally consistent data set for use in post-flight performance assessments.