Model Comparisons For Space Solar Cell End-Of-Life Calculations

NASA Astrophysics Data System (ADS)

Messenger, Scott; Jackson, Eric; Warner, Jeffrey; Walters, Robert; Evans, Hugh; Heynderickx, Daniel

2011-10-01

Space solar cell end-of-life (EOL) calculations are performed over a wide range of space radiation environments for GaAs-based single and multijunction solar cell technologies. Two general semi-empirical approaches will used to generate these EOL calculation results: 1) the JPL equivalent fluence (EQFLUX) and 2) the NRL displacement damage dose (SCREAM). This paper also includes the first results using the Monte Carlo-based version of SCREAM, called MC- SCREAM, which is now freely available online as part of the SPENVIS suite of programs.

New insights on short-term solar irradiance forecast for space weather applications

NASA Astrophysics Data System (ADS)

Vieira, L. A.; Dudok de Wit, T.; Balmaceda, L. A.; Dal Lago, A.; Da Silva, L. A.; Gonzalez, W. D.

2013-12-01

The conditions of the thermosphere, the ionosphere, the neutral atmosphere, and the oceans on time scales from days to millennia are highly dependent on the solar electromagnetic output, the solar irradiance. The development of physics-based solar irradiance models during the last decade improved significantly our understanding of the solar forcing on Earth's climate. These models are based on the assumption that most of the solar irradiance variability is related to the magnetic field structure of the Sun. Recently, these models were extended to allow short-term forecast (1 to 15 days) of the total and spectral solar irradiance. The extension of the irradiance models is based on solar surface magnetic flux models and/or artificial neural network models. Here, we discuss in details the irradiance forecast models based on observations of the solar surface magnetic field realized by the HMI instrument on board of SDO spacecraft. We constrained and validated the models by comparing the output of the models and observations of the solar irradiance made by instruments onboard The SORCE spacecraft. This study received funding from the European Community's Seventh Framework Programme (FP7/2007-2013, FP7-SPACE-2010-1) under the grant agreement nrs. 218816 (SOTERIA project, www.soteria-space.eu) and 261948 (ATMOP,www.atmop.eu), and by the CNPq/Brazil under the grant number 312488/2012-2. We also gratefully thank the instrument teams for making their data available.

Shuttle Engine Designs Revolutionize Solar Power

NASA Technical Reports Server (NTRS)

2014-01-01

The Space Shuttle Main Engine was built under contract to Marshall Space Flight Center by Rocketdyne, now part of Pratt & Whitney Rocketdyne (PWR). PWR applied its NASA experience to solar power technology and licensed the technology to Santa Monica, California-based SolarReserve. The company now develops concentrating solar power projects, including a plant in Nevada that has created 4,300 jobs during construction.

Advance on solar instrumentation in China

NASA Astrophysics Data System (ADS)

Yan, Yihua

2015-08-01

The solar observing facilities in China are introduced with the emphasis on the development in recent years and future plans for both ground and space-based solar instrumentations. The recent solar instruments are as follows: A new generation Chinese Spectral Radioreliograph (CSRH) has been constructed at Mingantu Observing Station in Zhengxiangbaiqi, inner Mongolia of China since 2013 and is in test observations now. CSRH has two arrays with 40 × 4.5 m and 60 × 2 m parabolic antennas covering 0.4-2 GHz and 2-15 GHz frequency range. CSRH is renamed as MUSER (Mingantu Ultrawide Spectral Radiheliograph) after its accomplishment. A new 1 m vacuum solar telescope (NVST) has been installed in 2010 at Fuxian lake, 60 km away from Kunming, Yunana. At present it is the best seeing place in China. A new telescope called ONSET (Optical and NIR Solar Eruption Tracer) has been established at the same site as NVST in 2011. ONSET has been put into operation since 2013. For future ground-based plans, Chinese Giant Solar Telescope (CGST) with spatial resolution equivalent to 8m and effective area of 5m full-aperture telescope has been proposed and was formally listed into the National Plans of Major Science & Technology Infrastructures in China. The pre-study and site survey for CGST have been pursued. A 1-meter mid-infrared telescope for precise measurement of the solar magnetic field has been funded by NSFC in 2014 as a national major scientific instrument development project. This project will develop the first mid-infrared solar magnetic observation instrument in the world aiming at increasing the precision of the transverse magnetic field measurement by one order of magnitude. For future ground-based plans, we promote the Deep-space Solar Observatory (DSO) with 1-m aperture telescope to be formally funded. The ASO-S (an Advanced Space-based Solar Observatory) has been supported in background phase by Space Science Program as a small mission. Other related space solar projects have also been proposed to promote the solar-terrestrial research.

Advanced Energy Conversion Technologies and Architectures for Earth and Beyond

NASA Technical Reports Server (NTRS)

Howell, Joe T.; Fikes, John C.; Phillips, Dane J.; Laycock, Rustin L.; ONeill, Mark; Henley, Mark W.; Fork, Richard L.

2006-01-01

Research, development and studies of novel space-based solar power systems, technologies and architectures for Earth and beyond are needed to reduce the cost of clean electrical power for terrestrial use and to provide a stepping stone for providing an abundance of power in space, i.e., manufacturing facilities, tourist facilities, delivery of power between objects in space, and between space and surface sites. The architectures, technologies and systems needed for space to Earth applications may also be used for in-space applications. Advances in key technologies, i.e., power generation, power management and distribution, power beaming and conversion of beamed power are needed to achieve the objectives of both terrestrial and extraterrestrial applications. There is a need to produce "proof-ofconcept" validation of critical WPT technologies for both the near-term, as well as far-term applications. Investments may be harvested in near-term beam safe demonstrations of commercial WPT applications. Receiving sites (users) include ground-based stations for terrestrial electrical power, orbital sites to provide power for satellites and other platforms, future space elevator systems, space vehicle propulsion, and space surface sites. Space surface receiving sites of particular interest include the areas of permanent shadow near the moon s North and South poles, where WPT technologies could enable access to ice and other useful resources for human exploration. This paper discusses work addressing a promising approach to solar power generation and beamed power conversion. The approach is based on a unique high-power solar concentrator array called Stretched Lens Array (SLA) applied to both solar power generation and beamed power conversion. Since both versions (solar and laser) of SLA use many identical components (only the photovoltaic cells need to be different), economies of manufacturing and scale may be realized by using SLA on both ends of the laser power beaming system in a space solar power application. Near-term uses of this SLA-laser-SLA system may include terrestrial and space exploration in near Earth space. Later uses may include beamed power for bases or vehicles on Mars. Strategies for developing energy infrastructures in space which utilize this technology are presented. This dual use system produces electrical energy efficiently from either coherent light, such as from a highly coherent laser, or from conventional solar illumination. This allows, for example, supplementing solar energy with energy provided by highly coherent laser illumination during periods of low solar illumination or no illumination. This reduces the need for batteries and alternate sources of power. The capability of using laser illumination in a lowest order Gaussian laser mode provides means for transmitting power optically with maximum efficiency and precision over the long distances characteristic of space. A preliminary receiving system similar to that described here, has been produced and tested under solar and laser illumination. A summary of results is given.

Small space station electrical power system design concepts

NASA Technical Reports Server (NTRS)

Jones, G. M.; Mercer, L. N.

1976-01-01

A small manned facility, i.e., a small space station, placed in earth orbit by the Shuttle transportation system would be a viable, cost effective addition to the basic Shuttle system to provide many opportunities for R&D programs, particularly in the area of earth applications. The small space station would have many similarities with Skylab. This paper presents design concepts for an electrical power system (EPS) for the small space station based on Skylab experience, in-house work at Marshall Space Flight Center, SEPS (Solar Electric Propulsion Stage) solar array development studies, and other studies sponsored by MSFC. The proposed EPS would be a solar array/secondary battery system. Design concepts expressed are based on maximizing system efficiency and five year operational reliability. Cost, weight, volume, and complexity considerations are inherent in the concepts presented. A small space station EPS based on these concepts would be highly efficient, reliable, and relatively inexpensive.

A generalized analysis of solar space heating in the United States

NASA Astrophysics Data System (ADS)

Clark, J. A.

A life-cycle model is developed for solar space heating within the United States that is based on the solar design data from the Los Alamos Scientific Laboratory. The model consists of an analytical relationship among five dimensionless parameters that include all pertinent technical, climatological, solar, operating and economic factors that influence the performance of a Solar Space Heating System. An important optimum condition presented is the 'Breakeven' metered cost of conventional fuel at which the cost of the solar system is equal to that of a conventional heating system. The effect of Federal (1980) and State (1979) income tax credits on these costs is determined. A parameter that includes both solar availability and solar system utilization is derived and plotted on a map of the U.S. This parameter shows the most favorable present locations for solar space heating application to be in the Central and Mountain States. The data employed are related to the rehabilitated solar data recently made available by the National Climatic Center (SOLMET).

New Voltage and Current Thresholds Determined for Sustained Space Plasma Arcing

NASA Technical Reports Server (NTRS)

Ferguson, Dale C.; Galofaro, Joel T.; Vayner, Boris V.

2003-01-01

It has been known for many years, based partly on NASA Glenn Research Center testing, that high-voltage solar arrays arc into the space plasma environment. Solar arrays are composed of solar cells in series with each other (a string), and the strings may be connected in parallel to produce the entire solar array power. Arcs on solar arrays can damage or destroy solar cells, and in the extreme case of sustained arcing, entire solar array strings, in a flash. In the case of sustained arcing (discovered at Glenn and applied to the design and construction of solar arrays on Space Systems/Loral (SS/Loral, Palo Alto, CA) satellites, Deep-Space 1, and Terra), an arc on one solar array string can couple to an adjacent string and continue to be powered by the solar array output until a permanent electrical short is produced. In other words, sustained arcs produced by arcs into the plasma (so-called trigger arcs) may turn into disastrous sustained arcs by involving other array strings.

Variability of the solar shape (before space dedicated missions)

NASA Astrophysics Data System (ADS)

Rozelot, J. P.; Damiani, C.; Lefebvre, S.

2009-12-01

Shrinking or expansion of the solar shape and irradiance variations are ultimately related to solar activity. We give here a review on existing ground-based or space solar radius measurements, extending the concept to shape changes. We show how helioseismology results allow us to look at the variations below the surface, where changes are not uniform, putting in evidence a new shallow layer, the leptocline, which is the seat of solar asphericities, radius variations with the 11-yr cycle and the cradle of complex physical processes: partial ionization of the light elements, opacities changes, superadiabaticity, strong gradient of rotation and pressure. Based on such physical grounds, we show why it is important to get accurate measurements from scheduled dedicated space missions: PICARD, SDO, DynaMICCS, ASTROMETRIA, SPHERIS. Such measurements will provide us a unique opportunity to study in detail the relationship between global solar properties and changes in the Sun's interior.

A theory of the n-i-p silicon solar cell

NASA Technical Reports Server (NTRS)

Goradia, C.; Weinberg, I.; Baraona, C.

1981-01-01

A computer model has been developed, based on an analytical theory of the high base resistivity BSF n(+)(pi)p(+) or p(+)(nu)n(+) silicon solar cell. The model makes very few assumptions and accounts for nonuniform optical generation, generation and recombination in the junction space charge region, and bandgap narrowing in the heavily doped regions. The paper presents calculated results based on this model and compares them to available experimental data. Also discussed is radiation damage in high base resistivity n(+)(pi)p(+) space solar cells.

An Early Prediction of Sunspot Cycle 25

NASA Astrophysics Data System (ADS)

Nandy, D.; Bhowmik, P.

2017-12-01

The Sun's magnetic activity governs our space environment, creates space weather and impacts our technologies and climate. With increasing reliance on space- and ground-based technologies that are subject to space weather, the need to be able to forecast the future activity of the Sun has assumed increasing importance. However, such long-range, decadal-scale space weather prediction has remained a great challenge as evident in the diverging forecasts for solar cycle 24. Based on recently acquired understanding of the physics of solar cycle predictability, we have devised a scheme to extend the forecasting window of solar cycles. Utilizing this we present an early forecast for sunspot cycle 25 which would be of use for space mission planning, satellite life-time estimates, and assessment of the long-term impacts of space weather on technological assets and planetary atmospheres.

Scattering Effects of Solar Panels on Space Station Antenna Performance

NASA Technical Reports Server (NTRS)

Panneton, Robert J.; Ngo, John C.; Hwu, Shian U.; Johnson, Larry A.; Elmore, James D.; Lu, Ba P.; Kelley, James S.

1994-01-01

Characterizing the scattering properties of the solar array panels is important in predicting Space Station antenna performance. A series of far-field, near-field, and radar cross section (RCS) scattering measurements were performed at S-Band and Ku-Band microwave frequencies on Space Station solar array panels. Based on investigation of the measured scattering patterns, the solar array panels exhibit similar scattering properties to that of the same size aluminum or copper panel mockup. As a first order approximation, and for worse case interference simulation, the solar array panels may be modeled using perfect reflecting plates. Numerical results obtained using the Geometrical Theory of Diffraction (GTD) modeling technique are presented for Space Station antenna pattern degradation due to solar panel interference. The computational and experimental techniques presented in this paper are applicable for antennas mounted on other platforms such as ship, aircraft, satellite, and space or land vehicle.

Our Explosive Sun

ERIC Educational Resources Information Center

Brown, D. S.

2009-01-01

The Sun's atmosphere is a highly structured but dynamic place, dominated by the solar magnetic field. Hot charged gas (plasma) is trapped on lines of magnetic force that can snap like an elastic band, propelling giant clouds of material out into space. A range of ground-based and space-based solar telescopes observe these eruptions, particularly…

An IBM PC-based math model for space station solar array simulation

NASA Technical Reports Server (NTRS)

Emanuel, E. M.

1986-01-01

This report discusses and documents the design, development, and verification of a microcomputer-based solar cell math model for simulating the Space Station's solar array Initial Operational Capability (IOC) reference configuration. The array model is developed utilizing a linear solar cell dc math model requiring only five input parameters: short circuit current, open circuit voltage, maximum power voltage, maximum power current, and orbit inclination. The accuracy of this model is investigated using actual solar array on orbit electrical data derived from the Solar Array Flight Experiment/Dynamic Augmentation Experiment (SAFE/DAE), conducted during the STS-41D mission. This simulator provides real-time simulated performance data during the steady state portion of the Space Station orbit (i.e., array fully exposed to sunlight). Eclipse to sunlight transients and shadowing effects are not included in the analysis, but are discussed briefly. Integrating the Solar Array Simulator (SAS) into the Power Management and Distribution (PMAD) subsystem is also discussed.

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 also handled with the modules in the Lund Space Weather Model. Interesting Links: Lund Space Weather and AI Center

Solar Pumped Solid State Lasers for Space Solar Power: Experimental Path

NASA Technical Reports Server (NTRS)

Fork, Richard L.; Carrington, Connie K.; Walker, Wesley W.; Cole, Spencer T.; Green, Jason J. A.; Laycock, Rustin L.

2003-01-01

We outline an experimentally based strategy designed to lead to solar pumped solid state laser oscillators useful for space solar power. Our method involves solar pumping a novel solid state gain element specifically designed to provide efficient conversion of sunlight in space to coherent laser light. Kilowatt and higher average power is sought from each gain element. Multiple such modular gain elements can be used to accumulate total average power of interest for power beaming in space, e.g., 100 kilowatts and more. Where desirable the high average power can also be produced as a train of pulses having high peak power (e.g., greater than 10(exp 10 watts). The modular nature of the basic gain element supports an experimental strategy in which the core technology can be validated by experiments on a single gain element. We propose to do this experimental validation both in terrestrial locations and also on a smaller scale in space. We describe a terrestrial experiment that includes diagnostics and the option of locating the laser beam path in vacuum environment. We describe a space based experiment designed to be compatible with the Japanese Experimental Module (JEM) on the International Space Station (ISS). We anticipate the gain elements will be based on low temperature (approx. 100 degrees Kelvin) operation of high thermal conductivity (k approx. 100 W/cm-K) diamond and sapphire (k approx. 4 W/cm-K). The basic gain element will be formed by sequences of thin alternating layers of diamond and Ti:sapphire with special attention given to the material interfaces. We anticipate this strategy will lead to a particularly simple, robust, and easily maintained low mass modelocked multi-element laser oscillator useful for space solar power.

Space station systems analysis study. Part 3: Documentation. Volume 7: SCB alternate EPS evaluation, task 10

NASA Technical Reports Server (NTRS)

1977-01-01

Power levels up to 100 kWe average were baselined for the electrical power system of the space construction base, a long-duration manned facility capable of supporting manufacturing and large scale construction projects in space. Alternatives to the solar array battery systems discussed include: (1) solar concentrator/brayton; (2) solar concentrator/thermionic; (3) isotope/brayton; (4) nuclear/brayton; (5) nuclear thermoelectric; and (6) nuclear thermionic.

Space solar power - An energy alternative

NASA Technical Reports Server (NTRS)

Johnson, R. W.

1978-01-01

The space solar power concept is concerned with the use of a Space Power Satellite (SPS) which orbits the earth at geostationary altitude. Two large symmetrical solar collectors convert solar energy directly to electricity using photovoltaic cells woven into blankets. The dc electricity is directed to microwave generators incorporated in a transmitting antenna located between the solar collectors. The antenna directs the microwave beam to a receiving antenna on earth where the microwave energy is efficiently converted back to dc electricity. The SPS design promises 30-year and beyond lifetimes. The SPS is relatively pollution free as it promises earth-equivalence of 80-85% efficient ground-based thermal power plant.

The LASP Interactive Solar IRradiance Datacenter (LISIRD)

NASA Astrophysics Data System (ADS)

Pankratz, C. K.; Lindholm, D. M.; Snow, M.; Knapp, B.; Woodraska, D.; Templeman, B.; Woods, T. N.; Eparvier, F. G.; Fontenla, J.; Harder, J.; McClintock, W. E.

2007-12-01

The Laboratory for Atmospheric and Space Physics (LASP) has been making space-based measurements of solar irradiance for many decades, and thus has established an extensive catalog of past and ongoing space- based solar irradiance measurements. In order to maximize the accessibility and usability of solar irradiance data and information from multiple missions, LASP is developing the LASP Interactive Solar IRradiance Datacenter (LISIRD) to better serve the needs of researchers, educators, and the general public. This data center is providing interactive and direct access to a comprehensive set of solar spectral irradiance measurements from the soft X-ray (XUV) at 0.1 nm up to the near infrared (NIR) at 2400 nm, as well as state-of-the-art measurements of Total Solar Irradiance (TSI). LASP researchers are also responsible for an extensive set of solar irradiance models and historical solar irradiance reconstructions, which will also be accessible via this data center over time. LISIRD currently provides access to solar irradiance data sets from the SORCE, TIMED-SEE, UARS-SOLSTICE, and SME instruments, spanning 1981 to the present, as well as a Lyman Alpha composite that is available from 1947 to the present. LISIRD also provides data products of interest to the space weather community, whose needs demand high time cadence and near real-time data delivery. This poster provides an overview of the LISIRD system, summarizes the data sets currently available, describes future plans and capabilities, and provides details on how to access solar irradiance data through LISIRD's various interfaces.

Evaluation of solar cells for potential space satellite power applications

NASA Technical Reports Server (NTRS)

1977-01-01

The evaluation focused on the following subjects: (1) the relative merits of alternative solar cell materials, based on performance and availability, (2) the best manufacturing methods for various solar cell options and the effects of extremely large production volumes on their ultimate costs and operational characteristics, (3) the areas of uncertainty in achieving large solar cell production volumes, (4) the effects of concentration ratios on solar array mass and system performance, (5) the factors influencing solar cell life in the radiation environment during transport to and in geosynchronous orbit, and (6) the merits of conducting solar cell manufacturing operations in space.

Space Weather and the Ground-Level Solar Proton Events of the 23rd Solar Cycle

NASA Astrophysics Data System (ADS)

Shea, M. A.; Smart, D. F.

2012-10-01

Solar proton events can adversely affect space and ground-based systems. Ground-level events are a subset of solar proton events that have a harder spectrum than average solar proton events and are detectable on Earth's surface by cosmic radiation ionization chambers, muon detectors, and neutron monitors. This paper summarizes the space weather effects associated with ground-level solar proton events during the 23rd solar cycle. These effects include communication and navigation systems, spacecraft electronics and operations, space power systems, manned space missions, and commercial aircraft operations. The major effect of ground-level events that affect manned spacecraft operations is increased radiation exposure. The primary effect on commercial aircraft operations is the loss of high frequency communication and, at extreme polar latitudes, an increase in the radiation exposure above that experienced from the background galactic cosmic radiation. Calculations of the maximum potential aircraft polar route exposure for each ground-level event of the 23rd solar cycle are presented. The space weather effects in October and November 2003 are highlighted together with on-going efforts to utilize cosmic ray neutron monitors to predict high energy solar proton events, thus providing an alert so that system operators can possibly make adjustments to vulnerable spacecraft operations and polar aircraft routes.

Solar astronomy

NASA Technical Reports Server (NTRS)

Rosner, Robert; Noyes, Robert; Antiochos, Spiro K.; Canfield, Richard C.; Chupp, Edward L.; Deming, Drake; Doschek, George A.; Dulk, George A.; Foukal, Peter V.; Gilliland, Ronald L.

1991-01-01

An overview is given of modern solar physics. Topics covered include the solar interior, the solar surface, the solar atmosphere, the Large Earth-based Solar Telescope (LEST), the Orbiting Solar Laboratory, the High Energy Solar Physics mission, the Space Exploration Initiative, solar-terrestrial physics, and adaptive optics. Policy and related programmatic recommendations are given for university research and education, facilitating solar research, and integrated support for solar research.

High temperature solar photon engines. [heat engines for terrestrial and space-based solar power plants

NASA Technical Reports Server (NTRS)

Hertzberg, A.; Decher, R.; Mattick, A. T.; Lau, C. V.

1978-01-01

High temperature heat engines designed to make maximum use of the thermodynamic potential of concentrated solar radiation are described. Plasmas between 2000 K and 4000 K can be achieved by volumetric absorption of radiation in alkali metal vapors, leading to thermal efficiencies up to 75% for terrestrial solar power plants and up to 50% for space power plants. Two machines capable of expanding hot plasmas using practical technology are discussed. A binary Rankine cycle uses fluid mechanical energy transfer in a device known as the 'Comprex' or 'energy exchanger.' The second machine utilizes magnetohydrodynamics in a Brayton cycle for space applications. Absorption of solar energy and plasma radiation losses are investigated for a solar superheater using potassium vapor.

NASA Marshall Space Flight Center solar observatory report, January - June 1991

NASA Technical Reports Server (NTRS)

Smith, James E.

1991-01-01

Given here is a summary of the solar vector magnetic field, H-alpha, and white-light observations made at the NASA/Marshall Space Flight Center (MSFC) Solar Observatory during its daily periods of operation. The MSFC Solar Observatory facilities consist of the Solar Magnetograph, an f/13, 30-cm Cassegrain system with a 3.5-cm image of the Sun, housed on top of a 12.8-meter tower; a 12.5-cm Razdow H-alpha telescope housed at the base of the tower; an 18-cm Questar telescope with a full aperture white-light filter mounted at the base of the tower; a 30-cm Cassegrain telescope located in a second metal dome; and a 16.5-cm H-alpha telescope mounted on side of the Solar Vector Magnetograph. A concrete block building provides office space, a darkroom for developing film and performing optical testing, a workshop, video displays, and a computer facility for data reduction.

NASA Marshall Space Flight Center Solar Observatory report, July - December 1991

NASA Technical Reports Server (NTRS)

Smith, James E.

1992-01-01

A summary is given of the solar vector magnetic field, H-alpha, and white light observations made at the NASA/Marshall Space Flight Center (MSFC) Solar Observatory during its daily periods of observation. The MSFC Solar Observatory facilities consist of the Solar Magnetograph, an f-13, 30 cm Cassegrain system with a 3.5 cm image of the Sun housed on top of a 12.8 meter tower, a 12.5 cm Razdow H-alpha telescope housed at the base of the tower, an 18 cm Questar telescope with a full aperture white-light filter mounted at the base of the tower, a 30 cm Cassegrain telescope located in a second metal dome, and a 16.5 cm H-alpha telescope mounted on the side of the Solar Vector Magnetograph. A concrete block building provides office space, a darkroom for developing film and performing optical testing, a workshop, video displays, and a computer facility for data reduction.

Monolithic-Structured Single-Layered Textile-Based Dye-Sensitized Solar Cells.

PubMed

Yun, Min Ju; Cha, Seung I; Kim, Han Seong; Seo, Seon Hee; Lee, Dong Y

2016-10-06

Textile-structured solar cells are frequently discussed in the literature due to their prospective applications in wearable devices and in building integrated solar cells that utilize their flexibility, mechanical robustness, and aesthetic appearance, but the current approaches for textile-based solar cells-including the preparation of fibre-type solar cells woven into textiles-face several difficulties from high friction and tension during the weaving process. This study proposes a new structural concept and fabrication process for monolithic-structured textile-based dye-sensitized solar cells that are fabricated by a process similar to the cloth-making process, including the preparation of wires and yarns that are woven for use in textiles, printed, dyed, and packaged. The fabricated single-layered textile-based dye-sensitized solar cells successfully act as solar cells in our study, even under bending conditions. By controlling the inter-weft spacing and the number of Ti wires for the photoelectrode conductor, we have found that the performance of this type of dye-sensitized solar cell was notably affected by the spacing between photoelectrodes and counter-electrodes, the exposed areas of Ti wires to photoelectrodes, and photoelectrodes' surface morphology. We believe that this study provides a process and concept for improved textile-based solar cells that can form the basis for further research.

Preliminary Design of the Brazilian's National Institute for Space Research Broadband Radiometer for Solar Observations

NASA Astrophysics Data System (ADS)

Berni, L. A.; Vieira, L. E. A.; Savonov, G. S.; Dal Lago, A.; Mendes, O.; Silva, M. R.; Guarnieri, F.; Sampaio, M.; Barbosa, M. J.; Vilas Boas, J. V.; Branco, R. H. F.; Nishimori, M.; Silva, L. A.; Carlesso, F.; Rodríguez Gómez, J. M.; Alves, L. R.; Vaz Castilho, B.; Santos, J.; Silva Paula, A.; Cardoso, F.

2017-10-01

The Total Solar Irradiance (TSI), which is the total radiation arriving at Earth's atmosphere from the Sun, is one of the most important forcing of the Earths climate. Measurements of the TSI have been made employing instruments on board several space-based platforms during the last four solar cycles. However, combining these measurements is still challenging due to the degradation of the sensor elements and the long-term stability of the electronics. Here we describe the preliminary efforts to design an absolute radiometer based on the principle of electrical substitution that is under development at Brazilian's National Institute for Space Research (INPE).

Space-Based Solar Power Conversion and Delivery Systems Study. Volume 1: Executive Summary

NASA Technical Reports Server (NTRS)

1977-01-01

The research concerning space-based solar power conversion and delivery systems is summarized. The potential concepts for a photovoltaic satellite solar power system was studied with emphasis on ground output power levels of 5,000 MW and 10,000 MW. A power relay satellite, and certain aspects of the economics of these systems were also studied. A second study phase examined in greater depth the technical and economic aspects of satellite solar power systems. Throughout this study, the focus was on the economics of satellite solar power. The results indicate technical feasibility of the concept, and provide a preliminary economic justification for the first phase of a substantial development program. A development program containing test satellites is recommended. Also, development of alternative solar cell materials (other than silicon) is recommended.

Failure Analysis in Space: International Space Station (ISS) Starboard Solar Alpha Rotary Joint (SARJ) Debris Analysis

NASA Technical Reports Server (NTRS)

Long, V. S.; Wright, M. C.; McDanels, S. J.; Lubas, D.; Tucker, B.; Marciniak, P. J.

2010-01-01

This slide presentation reviews the debris analysis of the Starboard Solar Alpha Rotary Joint (SARJ), a mechanism that is designed to keep the solar arrays facing the sun. The goal of this was to identify the failure mechanism based on surface morphology and to determine the source of debris through elemental and particle analysis.

Solar Technologies

ERIC Educational Resources Information Center

von Hippel, Frank; Williams, Robert H.

1975-01-01

As fossil fuels decrease in availability and environmental concerns increase, soalr energy is becoming a potential major energy source. Already solar energy is used for space heating in homes. Proposals for solar-electric generating systems include land-based or ocean-based collectors and harnessing wind and wave power. Photosynthesis can also…

The HESP (High Energy Solar Physics) project

NASA Technical Reports Server (NTRS)

Kai, K.

1986-01-01

A project for space observations of solar flares for the coming solar maximum phase is briefly described. The main objective is to make a comprehensive study of high energy phenomena of flares through simultaneous imagings in both hard and soft X-rays. The project will be performed with collaboration from US scientists. The HESP (High Energy Solar Physics) WG of ISAS (Institute of Space and Astronautical Sciences) has extensively discussed future aspects of space observations of high energy phenomena of solar flares based on successful results of the Hinotori mission, and proposed a comprehensive research program for the next solar maximum, called the HESP (SOLAR-A) project. The objective of the HESP project is to make a comprehensive study of both high energy phenomena of flares and quiet structures including pre-flare states, which have been left uncovered by SMM and Hinotori. For such a study simultaneous imagings with better resolutions in space and time in a wide range of energy will be extremely important.

Advantages of thin silicon solar cells for use in space

NASA Technical Reports Server (NTRS)

Denman, O. S.

1978-01-01

A system definition study on the Solar Power Satellite System showed that a thin, 50 micrometers, silicon solar cell has significant advantages. The advantages include a significantly lower performance degradation in a radiation environment and high power-to-mass ratios. The advantages of such cells for an employment in space is further investigated. Basic questions concerning the operation of solar cells are considered along with aspects of radiation induced performance degradation. The question arose in this connection how thin a silicon solar cell had to be to achieve resistance to radiation degradation and still have good initial performance. It was found that single-crystal silicon solar cells could be as thin as 50 micrometers and still develop high conversion efficiencies. It is concluded that the use of 50 micrometer silicon solar cells in space-based photovoltaic power systems would be advantageous.

Orbital Space Solar Power Option for a Lunar Village

NASA Technical Reports Server (NTRS)

Johnson, Les

2017-01-01

One of the most significant challenges to the implementation of a continuously manned lunar base is power. During the lunar day (14 Earth days), it is conceptually simple to deploy solar arrays to generate the estimated 35 kilowatts of continuous power required. However, generating this level of power during the lunar night (also 14 Earth days) has been an extremely difficult problem to solve. Conventional solutions range from the requirement that the base be located at the lunar south pole so as to take advantage of the continuous sunshine available there to developing a space-qualified nuclear reactor and power plant to generate the needed energy. There is a third option: Use the soon-to-be-available Space Launch System to place a space based solar power station in lunar orbit that would beam the needed energy to the lunar base. Several detailed studies have been performed by NASA, universities and others looking at the lunar south pole for locating the base. The results are encouraging: by taking advantage of the moon's orbital tilt, large solar arrays can be deployed there to track the sun continuously and generate the power needed to sustain the base. The problem with this approach is inherent to its design: it will only work at the lunar south pole. There is no other site on the Moon with geometry favorable to generating continuous solar power. NASA has also considered the development of a compact fission reactor and power plant to generate the needed power, allowing the base to be sited anywhere on the Moon. The problem with this approach is that there are no space fission reactors available, none are being planned and the cost of developing one is prohibitively expensive. Using an orbiting space based solar power station to generate electrical power and beam it to a base sited anywhere on the moon should therefore be considered. The technology to collect sunlight, generate greater than the estimated 35 kilowatts of power, and beam it to the surface using microwaves is available today. The problem with this concept in the past would have been the mass and packaging volume (for launch) required to put such a system in place in lunar orbit. This problem is potentially solved with the advent of the Space Launch System (SLS). The SLS, with its 70 mT launch capacity, it more than capable of placing such a system into lunar orbit in a single launch. This paper will examine the potential use of an SLS-launched, space solar power system in lunar orbit as the primary power source for a first-generation, continuously-occupied lunar base and compare it with the other power generation and storage options previously considered.

Millimeterwave Space Power Grid architecture development 2012

NASA Astrophysics Data System (ADS)

Komerath, Narayanan; Dessanti, Brendan; Shah, Shaan

This is an update of the Space Power Grid architecture for space-based solar power with an improved design of the collector/converter link, the primary heater and the radiator of the active thermal control system. The Space Power Grid offers an evolutionary approach towards TeraWatt-level Space-based solar power. The use of millimeter wave frequencies (around 220GHz) and Low-Mid Earth Orbits shrinks the size of the space and ground infrastructure to manageable levels. In prior work we showed that using Brayton cycle conversion of solar power allows large economies of scale compared to the linear mass-power relationship of photovoltaic conversion. With high-temperature materials permitting 3600 K temperature in the primary heater, over 80 percent cycle efficiency was shown with a closed helium cycle for the 1GW converter satellite which formed the core element of the architecture. Work done since the last IEEE conference has shown that the use of waveguides incorporated into lighter-than-air antenna platforms, can overcome the difficulties in transmitting millimeter wave power through the moist, dense lower atmosphere. A graphene-based radiator design conservatively meets the mass budget for the waste heat rejection system needed for the compressor inlet temperature. Placing the ultralight Mirasol collectors in lower orbits overcomes the solar beam spot size problem of high-orbit collection. The architecture begins by establishing a power exchange with terrestrial renewable energy plants, creating an early revenue generation approach with low investment. The approach allows for technology development and demonstration of high power millimeter wave technology. A multinational experiment using the International Space Station and another power exchange satellite is proposed to gather required data and experience, thus reducing the technical and policy risks. The full-scale architecture deploys pairs of Mirasol sunlight collectors and Girasol 1 GW converter satellites t- ramp up space solar power level to over 5.6 TeraWatts by year 50 from project start. Runway-based launch and landing are required to achieve the launch productivity as well as the cost reductions to enable such a large deployment on schedule. Advancements in the certainty of millimeter wave conversion technology and runway-based space access, are seen to be the outstanding issues in proceeding to full-scale Space Solar Power.

A Study of Defense Applications of Space Solar Power

NASA Astrophysics Data System (ADS)

Jaffe, Paul

2010-01-01

Space solar power (SSP) is generally considered to be the collection in space of energy from the sun and its wireless transmission from space for use on earth. It has been observed that the implementation of such a system could offer energy security, environmental, and technological advantages to those who would undertake its development. A study conducted by the Naval Research Laboratory (NRL) sought to determine if unique, cost effective, and efficient approaches exist for supplying significant power on demand for Navy, Marine Corps, or other Department of Defense applications by employing a space-based solar power system. The study was initiated by and prepared for top NRL management in part as a result of the publication of the National Security Space Office's (NSSO) report "Space-Based Solar Power as an Opportunity for Strategic Security." The NSSO report's recommendations included statements calling for the U.S. Government to conduct analyses, retire technical risk, and become an early demonstrator for SBSP. It should be noted that the principal objective of the NRL study differed significantly from that of the multitude of previous studies performed in reference to SBSP in that it focused on defense rather than utility grid applications.

Radiation energy conversion in space; Conference, 3rd, NASA Ames Research Center, Moffett Field, Calif., January 26-28, 1978, Technical Papers

NASA Technical Reports Server (NTRS)

Billman, K. W.

1978-01-01

Concepts for space-based conversion of space radiation energy into useful energy for man's needs are developed and supported by studies of costs, material and size requirements, efficiency, and available technology. Besides the more studied solar power satellite system using microwave transmission, a number of alternative space energy concepts are considered. Topics covered include orbiting mirrors for terrestrial energy supply, energy conversion at a lunar polar site, ultralightweight structures for space power, radiatively sustained cesium plasmas for solar electric conversion, solar pumped CW CO2 laser, superelastic laser energy conversion, laser-enhanced dynamics in molecular rate processes, and electron beams in space for energy storage.

Combined Radio and Space-Based Solar Observations: From Techniques to New Results - Preface

NASA Astrophysics Data System (ADS)

Kontar, Eduard P.; Nindos, Alexander

2018-06-01

The phenomena observed at the Sun have a variety of unique radio signatures that can be used to diagnose the processes in the solar atmosphere. The insights provided by radio observations are further enhanced when they are combined with observations from space-based telescopes. This Topical collection demonstrates the power of combination methodology at work and provides new results on i) type I solar radio bursts and thermal emission to study active regions; ii) type II and IV bursts to better understand the structure of coronal mass ejections; and iii) non-thermal gyro-synchrotron and/or type III bursts to improve the characterisation of particle acceleration in solar flares. The ongoing improvements in time, frequency, and spatial resolutions of ground-based telescopes reveal new levels in the complexity of solar phenomena and pose new questions.

Space-based solar power conversion and delivery systems study. Volume 3: Economic analysis of space-based solar power systems

NASA Technical Reports Server (NTRS)

Hazelrigg, G. A., Jr.

1976-01-01

A variety of economic and programmatic issues are discussed concerning the development and deployment of a fleet of space-based solar power satellites (SSPS). The costs, uncertainties and risks associated with the current photovoltaic SSPS configuration, and with issues affecting the development of an economically viable SSPS development program are analyzed. The desirability of a low earth orbit (LEO) demonstration satellite and a geosynchronous (GEO) pilot satellite is examined and critical technology areas are identified. In addition, a preliminary examination of utility interface issues is reported. The main focus of the effort reported is the development of SSPS unit production, and operation and maintenance cost models suitable for incorporation into a risk assessment (Monte Carlo) model (RAM). It is shown that the key technology area deals with the productivity of man in space, not, as might be expected, with some hardware component technology.

The role of space techniques in the understanding of solar variability

NASA Astrophysics Data System (ADS)

Bonnet, R. M.

1981-12-01

The advantages of using space for solar observations are discussed, and include avoidance of atmospheric effects, continuous observations by satellites, and the possibilities of solar studies from other planets or from above the ecliptic plane. Space-based viewing has allowed energy spectra studies from 310 nm down to gamma ray range, although instrument degradation due to radiation has often resulted in less precise instrument performance. Hands-on calibration on the Shuttle or the Salyut space station is seen as ameliorating the problem. Solar seismology, the design of a solar probe, solar magnetic measurement, and X-ray observations of coronal holes are outlined; the Solar Polar Mission is designed to carry UV, X-ray, and gamma ray measuring equipment. X-ray points (XRP), discovered from magnetic measurements on board Skylab, revealed that XRP varies 180 deg out of phase with respect to the sunspot number. Features and origins of the UV spectra are reviewed, and the necessity for precise measurement of the absolute intensity of the chromosphere is stressed as the means of understanding solar variability.

Feasibility Study of Space Based Solar Power to Tethered Aerostat Systems

NASA Technical Reports Server (NTRS)

Blank, Stephen J.; Leete, Stephen J.; Jaffe, Paul

2013-01-01

The feasibility of two-stage Space-Based Solar Power to Tethered Aerostat to Earth (SSP-TA) system architectures that offer significant advantages over conventional single stage space-to-earth architectures is being studied. There have been many proposals for the transmission of solar power collected in space to the surface of the earth so that solar energy could provide a major part of the electric power requirements on earth. There are, however, serious difficulties in implementing the single stage space-based solar power systems that have been previously studied. These difficulties arise due to: i) the cost of transporting the components needed for the extremely large microwave transmit beaming aperture into space orbit, ii) the even larger collection apertures required on earth, iii) the potential radiation hazard to personnel and equipment on earth, and iv) a lack of flexibility in location of the collection station on the earth. Two candidate system architectures are described here to overcome these difficulties. In both cases a two-stage space to tethered aerostat to earth transmission system (SSP-TA) is proposed. The use of high altitude tethered aerostats (or powered airships) avoids the effects of attenuation of EM energy propagating through the earth s lower atmosphere. This allows the use of beaming frequencies to be chosen from the range of high millimeter (THz) to near-infra-red (NIR) to the visible. This has the potential for: i) greatly reduced transportation costs to space, ii) much smaller receiver collection apertures and ground stations, iii) elimination of the potential radiation hazard to personnel and equipment on earth, and iv) ease in transportation and flexibility in location of the collection station on the earth. A preliminary comparison of system performance and efficiencies is presented.

Orbital Space Solar Power Option for a Lunar Village

NASA Technical Reports Server (NTRS)

Johnson, L.

2017-01-01

The international community is increasingly interested in returning humans to the Moon and this time establishing a permanent lunar base. There are several system level constraints that will drive the location for the base, chief among which are the need for continuous power and communications with the Earth. The NASA George C. Marshall Space Flight Center (MSFC) performed a study of placing an operational space based solar power station in lunar orbit to beam energy to the lunar base, or village, eliminating the need for the base to be located at the south pole or for it to be equipped with a fission power source.

Our Solar System, from the Outside

NASA Image and Video Library

2011-04-28

This graphic, based on data from NASA Voyager spacecraft, shows a model of what our solar system looks like to an observer outside in interstellar space, watching our solar system fly towards the observer.

ISS-based Development of Elements and Operations for Robotic Assembly of A Space Solar Power Collector

NASA Technical Reports Server (NTRS)

Valinia, Azita; Moe, Rud; Seery, Bernard D.; Mankins, John C.

2013-01-01

We present a concept for an ISS-based optical system assembly demonstration designed to advance technologies related to future large in-space optical facilities deployment, including space solar power collectors and large-aperture astronomy telescopes. The large solar power collector problem is not unlike the large astronomical telescope problem, but at least conceptually it should be easier in principle, given the tolerances involved. We strive in this application to leverage heavily the work done on the NASA Optical Testbed Integration on ISS Experiment (OpTIIX) effort to erect a 1.5 m imaging telescope on the International Space Station (ISS). Specifically, we examine a robotic assembly sequence for constructing a large (meter diameter) slightly aspheric or spherical primary reflector, comprised of hexagonal mirror segments affixed to a lightweight rigidizing backplane structure. This approach, together with a structured robot assembler, will be shown to be scalable to the area and areal densities required for large-scale solar concentrator arrays.

Advanced solar irradiances applied to satellite and ionospheric operational systems

NASA Astrophysics Data System (ADS)

Tobiska, W. Kent; Schunk, Robert; Eccles, Vince; Bouwer, Dave

Satellite and ionospheric operational systems require solar irradiances in a variety of time scales and spectral formats. We describe the development of a system using operational grade solar irradiances that are applied to empirical thermospheric density models and physics-based ionospheric models used by operational systems that require a space weather characterization. The SOLAR2000 (S2K) and SOLARFLARE (SFLR) models developed by Space Environment Technologies (SET) provide solar irradiances from the soft X-rays (XUV) through the Far Ultraviolet (FUV) spectrum. The irradiances are provided as integrated indices for the JB2006 empirical atmosphere density models and as line/band spectral irradiances for the physics-based Ionosphere Forecast Model (IFM) developed by the Space Environment Corporation (SEC). We describe the integration of these irradiances in historical, current epoch, and forecast modes through the Communication Alert and Prediction System (CAPS). CAPS provides real-time and forecast HF radio availability for global and regional users and global total electron content (TEC) conditions.

Space-Based Solar Power: A Technical, Economic, and Operational Assessment

DTIC Science & Technology

2015-04-01

reports also address alternative and renew- able sources such as biomass, wind, geothermal , and solar (thermal and photovoltaic), which are becom- ing...2025 using solar, wind, biomass, and geothermal energy generation technologies.86 Table 3. Army Sites for Terrestrial Solar Photovoltaic Power

Building a new space weather facility at the National Observatory of Athens

NASA Astrophysics Data System (ADS)

Kontogiannis, Ioannis; Belehaki, Anna; Tsiropoula, Georgia; Tsagouri, Ioanna; Anastasiadis, Anastasios; Papaioannou, Athanasios

2016-01-01

The PROTEAS project has been initiated at the Institute of Astronomy, Astrophysics, Space Applications and Remote Sensing (IAASARS) of the National Observatory of Athens (NOA). One of its main objectives is to provide observations, processed data and space weather nowcasting and forecasting products, designed to support the space weather research community and operators of commercial and industrial systems. The space weather products to be released by this facility, will be the result of the exploitation of ground-based, as well as space-borne observations and of model results and tools already available or under development by IAASARS researchers. The objective will be achieved through: (a) the operation of a small full-disk solar telescope to conduct regular observations of the Sun in the H-alpha line; (b) the construction of a database with near real-time solar observations which will be available to the community through a web-based facility (HELIOSERVER); (c) the development of a tool for forecasting Solar Energetic Particle (SEP) events in relation to observed solar eruptive events; (d) the upgrade of the Athens Digisonde with digital transceivers and the capability of operating in bi-static link mode and (e) the sustainable operation of the European Digital Upper Atmosphere Server (DIAS) upgraded with additional data sets integrated in an interface with the HELIOSERVER and with improved models for the real-time quantification of the effects of solar eruptive events in the ionosphere.

Ground Testing A 20-Meter Inflation Deployed Solar Sail

NASA Technical Reports Server (NTRS)

Mann, Troy; Behun, Vaughn; Lichodziejewski, David; Derbes, Billy; Sleight, David

2006-01-01

Solar sails have been proposed for a variety of future space exploration missions and provide a cost effective source of propellantless propulsion. Solar sails span very large areas to capture and reflect photons from the Sun and are propelled through space by the transfer of momentum from the photons to the solar sail. The thrust of a solar sail, though small, is continuous and acts for the life of the mission without the need for propellant. Recent advances in materials and ultra-low mass gossamer structures have enabled a host of useful space exploration missions utilizing solar sail propulsion. The team of L Garde, NASA Jet Propulsion Laboratory (JPL), Ball Aerospace, and NASA Langley Research Center, under the direction of the NASA In-Space Propulsion Office (ISP), has been developing a scalable solar sail configuration to address NASA s future space propulsion needs. The 100-m baseline solar sail concept was optimized around the one astronomical unit (AU) Geostorm mission, and features a Mylar sail membrane with a striped-net sail suspension architecture with inflation-deployed sail support beams consisting of inflatable sub-Tg (glass transition temperature) rigidizable semi-monocoque booms and a spreader system. The solar sail has vanes integrated onto the tips of the support beams to provide full 3-axis control of the solar sail. This same structural concept can be scaled to meet the requirements of a number of other NASA missions. Static and dynamic testing of a 20m scaled version of this solar sail concept have been completed in the Space Power Facility (SPF) at the NASA Glenn Plum Brook facility under vacuum and thermal conditions simulating the operation of a solar sail in space. This paper details the lessons learned from these and other similar ground based tests of gossamer structures during the three year solar sail project.

Distributed Space Solar Power

NASA Technical Reports Server (NTRS)

Fork, Richard L.

2001-01-01

The objective was to assess the feasibility of safely collecting solar power at geostationary orbit and delivering it to earth. A strategy which could harness a small fraction of the millions of gigawatts of sunlight passing near earth could adequately supply the power needs of earth and those of space exploration far into the future. Light collected and enhanced both spatially and temporally in space and beamed to earth provides probably the only practical means of safe and efficient delivery of this space solar power to earth. In particular, we analyzed the feasibility of delivering power to sites on earth at a comparable intensity, after conversion to a usable form, to existing power needs. Two major obstacles in the delivery of space solar power to earth are safety and the development of a source suitable for space. We focused our approach on: (1) identifying system requirements and designing a strategy satisfying current eye and skin safety requirements; and (2) identifying a concept for a potential space-based source for producing the enhanced light.

Fifth Space Weather Enterprise Forum Reaches New Heights

NASA Astrophysics Data System (ADS)

Williamson, Samuel P.; Babcock, Michael R.; Bonadonna, Michael F.

2011-09-01

As the world's commercial infrastructure grows more dependent on sensitive electronics and space-based technologies, the global economy is becoming increasingly vulnerable to solar storms. Experts from the federal government, academia, and the private sector met to discuss the societal effects of major solar storms and other space weather at the fifth annual Space Weather Enterprise Forum (SWEF), held on 21 June 2011 at the National Press Club in Washington, D. C. More than 200 members of the space weather community attended this year's SWEF, which focused on the consequences of severe space weather for national security, critical infrastructure, and human safety. Participants also addressed the question of how to prepare for and mitigate those consequences as the current solar cycle approaches and reaches its peak, expected in 2013. This year's forum included details of plans for a "Unified National Space Weather Capability," a new interagency initiative which will be implemented over the next two years, designed to improve forecasting, warning, and other services ahead of the coming solar maximum.

On space-based SETI

NASA Technical Reports Server (NTRS)

Stuiver, Willem

1990-01-01

Space-based antenna systems for the search of signals from extra-terrestrial intelligence are discussed. Independent studies of the ecliptic solar-sailing transfer problem from the geosynchronous departure orbit to Sun-Earth collinear transterrestrial liberation point were conducted. They were based on a relatively simple mathematical model describing attitude-controlled spacecraft motion in the ecliptic plane as governed by solar and terrestrial gravitational attraction together with the solar radiation pressure. The resulting equations of motion were integrated numerically for a relevant range of values of spacecraft area-to-mass ratio and for an appropriate spacecraft attitude-control law known to lead to Earth escape. Experimentation with varying initial conditions in the departure orbit, and with attitude-control law modification after having achieved Earth escape, established the feasibility of component deployment by means of solar sailing. Details are presented.

Space Solar Power Technology Demonstration for Lunar Polar Applications: Laser-Photovoltaic Wireless Power Transmission

NASA Technical Reports Server (NTRS)

Henley, M. W.; Fikes, J. C.; Howell, J.; Mankins, J. C.; Howell, Joe T. (Technical Monitor)

2002-01-01

Space Solar Power technology offers unique benefits for near-term NASA space science missions, which can mature this technology for other future applications. "Laser-Photo-Voltaic Wireless Power Transmission" (Laser-PV WPT) is a technology that uses a laser to beam power to a photovoltaic receiver, which converts the laser's light into electricity. Future Laser-PV WPT systems may beam power from Earth to satellites or large Space Solar Power satellites may beam power to Earth, perhaps supplementing terrestrial solar photo-voltaic receivers. In a near-term scientific mission to the moon, Laser-PV WPT can enable robotic operations in permanently shadowed lunar polar craters, which may contain ice. Ground-based technology demonstrations are proceeding, to mature the technology for this initial application, in the moon's polar regions.

Space weather: Why are magnetospheric physicists interested in solar explosive phenomena

NASA Astrophysics Data System (ADS)

Koskinen, H. E. J.; Pulkkinen, T. I.

That solar activity drives magnetospheric dynamics has for a long time been the basis of solar-terrestrial physics. Numerous statistical studies correlating sunspots, 10.7 cm radiation, solar flares, etc., with various magnetospheric and geomagnetic parameters have been performed. However, in studies of magnetospheric dynamics the role of the Sun has often remained in the background and only the actual solar wind impinging the magnetosphere has gained most of the attention. During the last few years a new applied field of solar-terrestrial physics, space weather, has emerged. The term refers to variable particle and field conditions in our space environment, which may be hazardous to space-borne or ground-based technological systems and can endanger human life and health. When the modern society is becoming increasingly dependent on space technology, the need for better modelling and also forecasting of space weather becomes urgent. While for post analysis of magnetospheric phenomena it is quite sufficient to include observations from the magnetospheric boundaries out to L1 where SOHO is located, these observations do not provide enough lead-time to run space weather forecasting models and to distribute the forecasts to potential customers. For such purposes we need improved physical understanding and models to predict which active processes on the Sun will impact the magnetosphere and what their expected consequences are. An important change of view on the role of the Sun as the origin of magnetospheric disturbances has taken place during last 10--20 years. For a long time, the solar flares were thought to be the most geoeffective solar phenomena. Now the attention has shifted much more towards coronal mass ejections and the SOHO coronal observations seem to have turned the epoch irreversibly. However, we are not yet ready to make reliable perdictions of the terrestrial environment based on CME observations. From the space weather viewpoint, the key questions are when a CME will be ejected, will it hit the Earth, what will its density and speed be, and how the magnetic field will be wrapped around the plasma cloud. This is clearly an enormous modelling task, but very forthwhile to carry further. Also forecasting of the solar energetic particle events would be very usefule as they form the most hazardous single effect on spaceflight, be that on the Space Station, on the Moon, or even further. We illustrate the chain of effects from the solar atmosphere to near-Earth space using some of the CME-associated magnetic storm events from the SOHO era.

Space, our next frontier; Proceedings of the conference, Dallas, TX, June 7, 8, 1984

DOE Office of Scientific and Technical Information (OSTI.GOV)

Musgrave, G.

1985-01-01

The present conference on space development encompasses space commercialization, legislative, legal, and insurance-related factors in current space programs, political aspects of space militarization and governmental control, the military future uses of space and their consequences, command and control issues arising in space, economic influences on space policy, and recent developments in space solar power generation concepts. Attention is given to public opinion surveys concerning the scientific, military, and economic uses of space, the Leasecraft orbital industrial infrastructure concept, capitalism and democracy in space development, the current status of space law on commercialization topics, the nature of Ballistic Missile Defense, themore » Soviet Space threat, the High Frontier concept for space defense, lunar solar power systems, solar power satellites, and the utilization of lunar resources for the reduction of lunar base construction costs. Such specific technical issues as microgravity crystal growth and directional solidification, electrophoresis operations for pharmaceuticals, and technical barriers to commercial access to space, are also noted.« less

Cloudy with a Chance of Solar Flares: The Sun as a Natural Hazard

NASA Technical Reports Server (NTRS)

Pellish, Jonathan

2017-01-01

Space weather is a naturally occurring phenomenon that represents a quantifiable risk to space- and ground-based infrastructure as well as society at large. Space weather hazards include permanent and correctable faults in computer systems, Global Positioning System (GPS) and high-frequency communication disturbances, increased airline passenger and astronaut radiation exposure, and electric grid disruption. From the National Space Weather Strategy, published by the Office of Science and Technology Policy in October 2015, space weather refers to the dynamic conditions of the space environment that arise from emissions from the Sun, which include solar flares, solar energetic particles, and coronal mass ejections. These emissions can interact with Earth and its surrounding space, including the Earth's magnetic field, potentially disrupting technologies and infrastructures. Space weather is measured using a range of space- and ground-based platforms that directly monitor the Sun, the Earth's magnetic field, the conditions in interplanetary space and impacts at Earth's surface, like neutron ground-level enhancement. The NASA Goddard Space Flight Center's Space Weather Research Center and their international collaborators in government, industry, and academia are working towards improved techniques for predicting space weather as part of the strategy and action plan to better quantify and mitigate space weather hazards. In addition to accurately measuring and predicting space weather, we also need to continue developing more advanced techniques for evaluating space weather impacts on space- and ground-based infrastructure. Within the Earth's atmosphere, elevated neutron flux driven by atmosphere-particle interactions from space weather is a primary risk source. Ground-based neutron sources form an essential foundation for quantifying space weather impacts in a variety of systems.

Space Station solar water heater

NASA Technical Reports Server (NTRS)

Horan, D. C.; Somers, Richard E.; Haynes, R. D.

1990-01-01

The feasibility of directly converting solar energy for crew water heating on the Space Station Freedom (SSF) and other human-tended missions such as a geosynchronous space station, lunar base, or Mars spacecraft was investigated. Computer codes were developed to model the systems, and a proof-of-concept thermal vacuum test was conducted to evaluate system performance in an environment simulating the SSF. The results indicate that a solar water heater is feasible. It could provide up to 100 percent of the design heating load without a significant configuration change to the SSF or other missions. The solar heater system requires only 15 percent of the electricity that an all-electric system on the SSF would require. This allows a reduction in the solar array or a surplus of electricity for onboard experiments.

Potential high efficiency solar cells: Applications from space photovoltaic research

NASA Technical Reports Server (NTRS)

Flood, D. J.

1986-01-01

NASA involvement in photovoltaic energy conversion research development and applications spans over two decades of continuous progress. Solar cell research and development programs conducted by the Lewis Research Center's Photovoltaic Branch have produced a sound technology base not only for the space program, but for terrestrial applications as well. The fundamental goals which have guided the NASA photovoltaic program are to improve the efficiency and lifetime, and to reduce the mass and cost of photovoltaic energy conversion devices and arrays for use in space. The major efforts in the current Lewis program are on high efficiency, single crystal GaAs planar and concentrator cells, radiation hard InP cells, and superlattice solar cells. A brief historical perspective of accomplishments in high efficiency space solar cells will be given, and current work in all of the above categories will be described. The applicability of space cell research and technology to terrestrial photovoltaics will be discussed.

Solar System Science with the Twinkle Space Mission

NASA Astrophysics Data System (ADS)

Bowles, N.; Lindsay, S.; Tessenyi, M.; Tinetti, G.; Savini, G.; Tennyson, J.; Pascale, E.; Jason, S.; Vora, A.

2017-09-01

Twinkle is a space-based telescope mission designed for the spectroscopic observation (0.4 to 4.5 μm) of exoplanet atmospheres and Solar System objects. The system design and mission implementation are based on existing, well studied concepts pioneered by Surrey Satellite Technology Ltd for low-Earth orbit Earth Observation satellites, supported by a novel international access model to allow facility access to researchers worldwide. Whilst Twinkle's primary science goal is the observation of exoplanet atmospheres its wide spectroscopic range and photometric stability also make it a unique platform for the observation of Solar system objects.

Economic feasibility of solar water and space heating.

PubMed

Bezdek, R H; Hirshberg, A S; Babcock, W H

1979-03-23

The economic feasibility in 1977 and 1978 of solar water and combined water and space heating is analyzed for single-family detached residences and multi-family apartment buildings in four representative U.S. cities: Boston, Massachusetts; Washington, D.C.; Grand Junction, Colorado; and Los Angeles, California. Three economic decision criteria are utilized: payback period, years to recovery of down payment, and years to net positive cash flow. The cost competitiveness of the solar systems compared to heating systems based on electricity, fuel oil, and natural gas is then discussed for each city, and the impact of the federal tax credit for solar energy systems is assessed. It is found that even without federal incentives some solar water and space heating systems are competitive. Enactment of the solar tax credit, however, greatly enhances their competitiveness. The implications of these findings for government tax and energy pricing policies are discussed.

Skylab

NASA Image and Video Library

1971-08-01

The Apollo Telescope Mount (ATM) was designed and developed by the Marshall Space Flight Center and served as the primary scientific instrument unit aboard Skylab (1973-1979). The ATM consisted of eight scientific instruments as well as a number of smaller experiments. One scientific instrument was the ATM solar shield that formed the base for the rack/frame instrument and the instrument canister. The solar shield contained aperture doors for each instrument to protect against solar radiation and space contamination.

Inflatable robotics for planetary applications

NASA Technical Reports Server (NTRS)

Jones, Jack A.

2001-01-01

Space Inflatable vehicles have been finding popularity in recent years for applications as varied as spacecraft antennas, space-based telescopes, solar sails, and manned habitats [1]. Another branch of space inflatable technology has also considered developing ambient gasfilled, solar balloons for Mars as well as ambient gasfilled inflatable rovers [2]. More recently, some other intriguing space-inflatable vehicles have been proposed for the gas planets and Pluto, as well as for Saturn's moon, Titan, Neptune's moon, Triton, and Jupiter's moon, Io [3].

The Solar Umbrella: A Low-cost Demonstration of Scalable Space Based Solar Power

NASA Technical Reports Server (NTRS)

Contreras, Michael T.; Trease, Brian P.; Sherwood, Brent

2013-01-01

Within the past decade, the Space Solar Power (SSP) community has seen an influx of stakeholders willing to entertain the SSP prospect of potentially boundless, base-load solar energy. Interested parties affiliated with the Department of Defense (DoD), the private sector, and various international entities have all agreed that while the benefits of SSP are tremendous and potentially profitable, the risk associated with developing an efficient end to end SSP harvesting system is still very high. In an effort to reduce the implementation risk for future SSP architectures, this study proposes a system level design that is both low-cost and seeks to demonstrate the furthest transmission of wireless power to date. The overall concept is presented and each subsystem is explained in detail with best estimates of current implementable technologies. Basic cost models were constructed based on input from JPL subject matter experts and assume that the technology demonstration would be carried out by a federally funded entity. The main thrust of the architecture is to demonstrate that a usable amount of solar power can be safely and reliably transmitted from space to the Earth's surface; however, maximum power scalability limits and their cost implications are discussed.

Guide to solar reference spectra and irradiance models

NASA Astrophysics Data System (ADS)

Tobiska, W. Kent

The international standard for determining solar irradiances was published by the International Standards Organization (ISO) in May 2007. The document, ISO 21348 Space Environment (natural and artificial) - Process for determining solar irradiances, describes the process for representing solar irradiances. We report on the next progression of standards work, i.e., the development of a guide that identifies solar reference spectra and irradiance models for use in engineering design or scientific research. This document will be produced as an AIAA Guideline and ISO Technical Report. It will describe the content of the reference spectra and models, uncertainties and limitations, technical basis, data bases from which the reference spectra and models are formed, publication references, and sources of computer code for reference spectra and solar irradiance models, including those which provide spectrally-resolved lines as well as solar indices and proxies and which are generally recognized in the solar sciences. The document is intended to assist aircraft and space vehicle designers and developers, heliophysicists, geophysicists, aeronomers, meteorologists, and climatologists in understanding available models, comparing sources of data, and interpreting engineering and scientific results based on different solar reference spectra and irradiance models.

Space-based solar power generation using a distributed network of satellites and methods for efficient space power transmission

NASA Astrophysics Data System (ADS)

McLinko, Ryan M.; Sagar, Basant V.

2009-12-01

Space-based solar power (SSP) generation is being touted as a solution to our ever-increasing energy consumption and dependence on fossil fuels. Satellites in Earth's orbit can capture solar energy through photovoltaic cells and transmit that power to ground based stations. Solar cells in orbit are not hindered by weather, clouds, or night. The energy generated by this process is clean and pollution-free. Although the concept of space-based solar power was initially proposed nearly 40 years ago, the level of technology in photovoltaics, power transmission, materials, and efficient satellite design has finally reached a level of maturity that makes solar power from space a feasible prospect. Furthermore, new strategies in methods for solar energy acquisition and transmission can lead to simplifications in design, reductions in cost and reduced risk. This paper proposes using a distributed array of small satellites to collect power from the Sun, as compared to the more traditional SSP design that consists of one monolithic satellite. This concept mitigates some of SSP's most troublesome historic constraints, such as the requirement for heavy lift launch vehicles and the need for significant assembly in space. Instead, a larger number of smaller satellites designed to collect solar energy are launched independently. A high frequency beam will be used to aggregate collected power into a series of transmission antennas, which beam the energy to Earth's surface at a lower frequency. Due to the smaller power expectations of each satellite and the relatively short distance of travel from low earth orbit, such satellites can be designed with smaller arrays. The inter-satellite rectenna devices can also be smaller and lighter in weight. Our paper suggests how SSP satellites can be designed small enough to fit within ESPA standards and therefore use rideshare to achieve orbit. Alternatively, larger versions could be launched on Falcon 9s or on Falcon 1s with booster stages. The only satellites that are constrained to a significant mass are the beam-down satellites, which still require significant transmission arrays to sufficiently focus the beams targeting corresponding ground stations. With robust design and inherent redundancy built-in, power generation and transmission will not be interrupted in the event of mishaps like space debris collision. Furthermore, the "plug and play" nature of this system significantly reduces the cost, complexity, and risk of upgrading the system. The distributed nature of smallsat clusters maximizes the use of economies of scale. This approach retains some problems of older designs and introduces additional ones. Mitigations will be explored further. For example, the distributed nature of the system requires very precise coordination between and among satellites and a mature attitude control and determination system. Such a design incorporates multiple beaming stages, which has the potential to reduce overall system efficiency. Although this design eliminates the need for space assembly, it retains the challenge of significant on-orbit deployment of solar and transmission arrays. Space power "beaming" is a three step process that involves: 1) conversion of dc power generated by solar cells on the satellite into an electromagnetic wave of suitable frequency, 2) transmission of that wave to power stations on ground, and 3) conversion of the radio waves back into dc power. A great deal of research has been done on the use of microwaves for this purpose. Various factors that affect efficient power generation and transmission will be analyzed in this paper. Based on relevant theory and performance and optimization models, the paper proposes solutions that will help make space-based solar power generation a practical and viable option for addressing the world's growing energy needs.

Space Weather: The Solar Perspective

NASA Astrophysics Data System (ADS)

Schwenn, Rainer

2006-08-01

The term space weather refers to conditions on the Sun and in the solar wind, magnetosphere, ionosphere, and thermosphere that can influence the performance and reliability of space-borne and ground-based technological systems and that can affect human life and health. Our modern hi-tech society has become increasingly vulnerable to disturbances from outside the Earth system, in particular to those initiated by explosive events on the Sun: Flares release flashes of radiation that can heat up the terrestrial atmosphere such that satellites are slowed down and drop into lower orbits, solar energetic particles accelerated to near-relativistic energies may endanger astronauts traveling through interplanetary space, and coronal mass ejections are gigantic clouds of ionized gas ejected into interplanetary space that after a few hours or days may hit the Earth and cause geomagnetic storms. In this review, I describe the several chains of actions originating in our parent star, the Sun, that affect Earth, with particular attention to the solar phenomena and the subsequent effects in interplanetary space.

Exploring the Solar System: A Literature Unit within a Whole Language Context.

ERIC Educational Resources Information Center

Sandel, Lenore

A useful framework for literature-based instruction is the curriculum related literature unit which provides a total resource for content area teaching. Such a unit could be based on the science curriculum, "Exploring the Solar System," and could be developed thematically through topics of space or the solar system. The teacher's initial…

The fast development of solar terrestrial sciences in Taiwan

NASA Astrophysics Data System (ADS)

Liu, Jann-Yenq; Chang, Loren Chee-Wei; Chao, Chi-Kuang; Chen, Ming-Quey; Chu, Yen-Hsyang; Hau, Lin-Ni; Huang, Chien-Ming; Kuo, Cheng-Ling; Lee, Lou-Chuang; Lyu, Ling-Hsiao; Lin, Chia-Hsien; Pan, Chen-Jeih; Shue, Jih-Hong; Su, Ching-Lun; Tsai, Lung-Chih; Yang, Ya-Hui; Lin, Chien-Hung; Hsu, Rue-Ron; Su, Han-Tzong

2016-12-01

In Taiwan, research and education of solar terrestrial sciences began with a ground-based ionosonde operated by Ministry of Communications in 1952 and courses of ionospheric physics and space physics offered by National Central University (NCU) in 1959, respectively. Since 1990, to enhance both research and education, the Institute of Space Science at NCU has been setting up and operating ground-based observations of micropulsations, very high-frequency radar, low-latitude ionospheric tomography network, high-frequency Doppler sounder, digital ionosondes, and total electron content (TEC) derived from ground-based GPS receivers to study the morphology of the ionosphere for diurnal, seasonal, geophysical, and solar activity variations, as well as the ionosphere response to solar flares, solar wind, solar eclipses, magnetic storms, earthquakes, tsunami, and so on. Meanwhile, to have better understanding on physics and mechanisms, model simulations for the heliosphere, solar wind, magnetosphere, and ionosphere are also introduced and developed. After the 21 September 1999 Mw7.6 Chi-Chi earthquake, seismo-ionospheric precursors and seismo-traveling ionospheric disturbances induced by earthquakes become the most interesting and challenging research topics of the world. The development of solar terrestrial sciences grows even much faster after National Space Origination has been launching a series of FORMOSAT satellites since 1999. ROCSAT-1 (now renamed FORMOSAT-1) measures the ion composition, density, temperature, and drift velocity at the 600-km altitude in the low-latitude ionosphere; FORMOSAT-2 is to investigate lightning-induced transient luminous events, polar aurora, and upper atmospheric airglow, and FORMOSAT-3 probes ionospheric electron density profiles of the globe. In the near future, FORMOSAT-5 and FORMOSAT-7/COSMIC-2 will be employed for studying solar terrestrial sciences. These satellite missions play an important role on the recent development of solar terrestrial sciences in Taiwan.

Solar-energy-system performance-evaluation update: El Toro Library, El Toro, California, December 1981-August 1982

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kendall, P.W.

The El Toro Library is a one-story facility that contains 10,000 square feet of floor area. The solar energy system was designed to provide 97% of the space heating load and 60% of the space cooling load. The solar energy system incorporates 82 panels with a gross area of 1427 square feet of evacuated tubular glass collectors (TC-100) manufactured by General Electric. The storage tank is a 1500-gallon insulated steel tank which is located outside, above ground level. The space heating subsystem uses solar energy from storage and/or thermal energy from the natural-gas-fired boiler. The space cooling subsystem uses anmore » absorption chiller to provide chilled water to the air-handling unit. As compared to the previous year, performance over the nine-month monitoring period was improved, based on overall solar contribution to the load. When compared to design values, the overall performance was poor. Overall solar fraction was an estimated 22% of the 220 million Btu system load. A total of 122 million Btu of solar energy was used by the space conditioning system. Auxiliary fossil fuel consumption was 608 million Btu, or 595,800 cubic feet of natural gas. Auxiliary thermal energy was a measured 68% of the auxiliary fossil fuel consumed. The solar savings ratio, a measure of the solar contribution to the load discounted by solar operating energy, averaged 19% during the analysis period. The previous year, the solar savings ratio was 16%.« less

In-Space Structural Validation Plan for a Stretched-Lens Solar Array Flight Experiment

NASA Technical Reports Server (NTRS)

Pappa, Richard S.; Woods-Vedeler, Jessica A.; Jones, Thomas W.

2001-01-01

This paper summarizes in-space structural validation plans for a proposed Space Shuttle-based flight experiment. The test article is an innovative, lightweight solar array concept that uses pop-up, refractive stretched-lens concentrators to achieve a power/mass density of at least 175 W/kg, which is more than three times greater than current capabilities. The flight experiment will validate this new technology to retire the risk associated with its first use in space. The experiment includes structural diagnostic instrumentation to measure the deployment dynamics, static shape, and modes of vibration of the 8-meter-long solar array and several of its lenses. These data will be obtained by photogrammetry using the Shuttle payload-bay video cameras and miniature video cameras on the array. Six accelerometers are also included in the experiment to measure base excitations and small-amplitude tip motions.

Inflatable Vehicles for In-Situ Exploration of Titan

NASA Technical Reports Server (NTRS)

Jones, J. A.

2001-01-01

Space Inflatable vehicles have been finding popularity in recent years for applications as varied as spacecraft antennas, space-based telescopes, solar sails, and manned habitats. Another branch of space inflatable technology has also considered developing ambient-filled, solar balloons for Mars as well as ambient-filled inflatable rovers. More recently, some of these inflatable technologies have been applied to the outer solar system bodies with the result that there are some rather unique and compelling inflatable mission capabilities for in situ explorations of Titan, Triton, Uranus, and Neptune. Additional information is contained in the original extended abstract.

Space Station Engineering and Technology Development. Proceedings of the Panel on Solar Thermodynamics Research and Technology Development, July 31, 1985

NASA Technical Reports Server (NTRS)

1985-01-01

Solar thermodynamics research and technology is reported. Comments on current program activity and future plans with regard to satisfying potential space station electric power generation requirements are provided. The proceedings contain a brief synopsis of the presentations to the panel, including panel comments, and a summary of the panel's observations. Selected presentation material is appended. Onboard maintainability and repair in space research and technology plan, solar thermodynamic research, program performance, onboard U.S. ground based mission control, and technology development rad maps from 10 C to the growth station are addressed.

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.

Extraterrestrial applications of solar optics for interior illumination

NASA Technical Reports Server (NTRS)

Eijadi, David A.; Williams, Kyle D.

1992-01-01

Solar optics is a terrestrial technology that has potential extraterrestrial applications. Active solar optics (ASO) and passive solar optics (PSO) are two approaches to the transmission of sunlight to remote interior spaces. Active solar optics is most appropriate for task illumination, while PSO is most appropriate for general illumination. Research into solar optics, motivated by energy conservation, has produced lightweight and low-cost materials, products that have applications to NASA's Controlled Ecological Life Support System (CELSS) program and its lunar base studies. Specifically, prism light guides have great potential in these contexts. Several applications of solar optics to lunar base concepts are illustrated.

Future Photovoltaic Power Generation for Space-Based Power Utilities

NASA Technical Reports Server (NTRS)

Bailey, Sheila; Landis, Geoffrey; Hepp, Aloysius; Raffaelle, Ryne

2002-01-01

This paper discusses requirements for large earth orbiting power stations that can serve as central utilities for other orbiting spacecraft, or for beaming power to the earth itself. 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 high power mission applications are addressed.

Overview of NASA Heliophysics and the Science of Space Weather

NASA Astrophysics Data System (ADS)

Talaat, E. R.

2017-12-01

In this paper, an overview is presented on the various activities within NASA that address space weather-related observations, model development, and research to operations. Specific to space weather, NASA formulates and implements, through the Heliophysics division, a national research program for understanding the Sun and its interactions with the Earth and the Solar System and how these phenomena impact life and society. NASA researches and prototypes new mission and instrument capabilities in this area, providing new physics-based algorithms to advance the state of solar, space physics, and space weather modeling.

Predicting efficiency of solar cells based on transparent conducting electrodes

NASA Astrophysics Data System (ADS)

Kumar, Ankush

2017-01-01

Efficiency of a solar cell is directly correlated with the performance of its transparent conducting electrodes (TCEs) which dictates its two core processes, viz., absorption and collection efficiencies. Emerging designs of a TCE involve active networks of carbon nanotubes, silver nanowires and various template-based techniques providing diverse structures; here, voids are transparent for optical transmittance while the conducting network acts as a charge collector. However, it is still not well understood as to which kind of network structure leads to an optimum solar cell performance; therefore, mostly an arbitrary network is chosen as a solar cell electrode. Herein, we propose a new generic approach for understanding the role of TCEs in determining the solar cell efficiency based on analysis of shadowing and recombination losses. A random network of wires encloses void regions of different sizes and shapes which permit light transmission; two terms, void fraction and equivalent radius, are defined to represent the TCE transmittance and wire spacings, respectively. The approach has been applied to various literature examples and their solar cell performance has been compared. To obtain high-efficiency solar cells, optimum density of the wires and their aspect ratio as well as active layer thickness are calculated. Our findings show that a TCE well suitable for one solar cell may not be suitable for another. For high diffusion length based solar cells, the void fraction of the network should be low while for low diffusion length based solar cells, the equivalent radius should be lower. The network with less wire spacing compared to the diffusion length behaves similar to continuous film based TCEs (such as indium tin oxide). The present work will be useful for architectural as well as material engineering of transparent electrodes for improvisation of solar cell performance.

The Future of Space Astronomy.

ERIC Educational Resources Information Center

Field, George B.

1984-01-01

Discusses various aspects of space astronomy, considering advantages, the space telescope and ground-based astronomy, an orbiting astrophysics facility, solar physics, and other areas. Indicates that earth-based astronomy will continue to be carried out there and space astronomy will be limited to observations that can be carried out only from…

Biological effects and physics of solar and galactic cosmic radiation, Part B; Proceedings of a NATO Advanced Study Institute on Biological Effects and Physics of Solar and Galactic Cosmic Radiation, Algarve, Portugal, Oct. 13-23, 1991

NASA Technical Reports Server (NTRS)

Swenberg, Charles E. (Editor); Horneck, Gerda (Editor); Stassinopoulos, E. G. (Editor)

1993-01-01

Since there is an increasing interest in establishing lunar bases and exploring Mars by manned missions, it is important to develop appropriate risk estimates and radiation protection guidelines. The biological effects and physics of solar and galactic cosmic radiation are examined with respect to the following: the radiation environment of interplanetary space, the biological responses to radiation in space, and the risk estimates for deep space missions. There is a need for a long-term program where ground-based studies can be augmented by flight experiments and an international standardization with respect to data collection, protocol comparison, and formulation of guidelines for future missions.

Ratioing methods for in-flight response calibration of space-based spectro-radiometers, operating in the solar spectral region

NASA Astrophysics Data System (ADS)

Lobb, Dan

2017-11-01

One of the most significant problems for space-based spectro-radiometer systems, observing Earth from space in the solar spectral band (UV through short-wave IR), is in achievement of the required absolute radiometric accuracy. Classical methods, for example using one or more sun-illuminated diffusers as reflectance standards, do not generally provide methods for monitoring degradation of the in-flight reference after pre-flight characterisation. Ratioing methods have been proposed that provide monitoring of degradation of solar attenuators in flight, thus in principle allowing much higher confidence in absolute response calibration. Two example methods are described. It is shown that systems can be designed for relatively low size and without significant additions to the complexity of flight hardware.

Studies of humid continental haze during SPACE

NASA Technical Reports Server (NTRS)

Bowdle, D. A.; Greene, W. A.

1985-01-01

A concept for a solar radiometer network to provide supporting data during the Satellite Preciptiation and Cloud Experiment (SPACE) was developed. Each of the 9 prime and 10 supplementary SPACE ground sites will be equipped with an upward pointing global solar pyranometer. About half of the sites will also be equipped with upward pointing diffuse (shade ring) solar pyranometers, and a downward pointing global albedo pyranometer. These radiometers will be used to monitor the spatial and temporal variability of solar insolation and haze optical depth. The insolation data will ultimately be input to numerical models of the pre-storm and near-storm boundary layer. The optical depth data will be compared with simultaneous measurements from airborne and satellite-based passive visible radiometers and airborne lidars.

Solar Atmosphere to Earth's Surface: Long Lead Time dB/dt Predictions with the Space Weather Modeling Framework

NASA Astrophysics Data System (ADS)

Welling, D. T.; Manchester, W.; Savani, N.; Sokolov, I.; van der Holst, B.; Jin, M.; Toth, G.; Liemohn, M. W.; Gombosi, T. I.

2017-12-01

The future of space weather prediction depends on the community's ability to predict L1 values from observations of the solar atmosphere, which can yield hours of lead time. While both empirical and physics-based L1 forecast methods exist, it is not yet known if this nascent capability can translate to skilled dB/dt forecasts at the Earth's surface. This paper shows results for the first forecast-quality, solar-atmosphere-to-Earth's-surface dB/dt predictions. Two methods are used to predict solar wind and IMF conditions at L1 for several real-world coronal mass ejection events. The first method is an empirical and observationally based system to estimate the plasma characteristics. The magnetic field predictions are based on the Bz4Cast system which assumes that the CME has a cylindrical flux rope geometry locally around Earth's trajectory. The remaining plasma parameters of density, temperature and velocity are estimated from white-light coronagraphs via a variety of triangulation methods and forward based modelling. The second is a first-principles-based approach that combines the Eruptive Event Generator using Gibson-Low configuration (EEGGL) model with the Alfven Wave Solar Model (AWSoM). EEGGL specifies parameters for the Gibson-Low flux rope such that it erupts, driving a CME in the coronal model that reproduces coronagraph observations and propagates to 1AU. The resulting solar wind predictions are used to drive the operational Space Weather Modeling Framework (SWMF) for geospace. Following the configuration used by NOAA's Space Weather Prediction Center, this setup couples the BATS-R-US global magnetohydromagnetic model to the Rice Convection Model (RCM) ring current model and a height-integrated ionosphere electrodynamics model. The long lead time predictions of dB/dt are compared to model results that are driven by L1 solar wind observations. Both are compared to real-world observations from surface magnetometers at a variety of geomagnetic latitudes. Metrics are calculated to examine how the simulated solar wind drivers impact forecast skill. These results illustrate the current state of long-lead-time forecasting and the promise of this technology for operational use.

The magnetic field of the earth - Performance considerations for space-based observing systems

NASA Technical Reports Server (NTRS)

Webster, W. J., Jr.; Taylor, P. T.; Schnetzler, C. C.; Langel, R. A.

1985-01-01

Basic problems inherent in carrying out observations of the earth magnetic field from space are reviewed. It is shown that while useful observations of the core and crustal fields are possible at the peak of the solar cycle, the greatest useful data volume is obtained during solar minimum. During the last three solar cycles, the proportion of data with a planetary disturbance index of less than 2 at solar maximum was in the range 0.4-0.8 in comparison with solar minimum. It is found that current state of the art orbit determination techniques should eliminate orbit error as a problem in gravitational field measurements from space. The spatial resolution obtained for crustal field anomalies during the major satellite observation programs of the last 30 years are compared in a table. The relationship between observing altitude and the spatial resolution of magnetic field structures is discussed. Reference is made to data obtained using the Magsat, the Polar Orbiting Geophysical Observatory (POGO), and instruments on board the Space Shuttle.

Space Based Observations of Coronal Cavities in Conjunction with the Total Solar Eclipse of July 2010

NASA Technical Reports Server (NTRS)

Kucera, T. A.; Berger, T. E.; Druckmuller, M.; Dietzel, M.; Gibson, S. E.; Habbal, S. R.; Morgan, H.; Reeves, K. K.; Schmit, D. J.; Seaton, D. B.

2010-01-01

In conjunction with the total solar eclipse on July 11, 2010 we coordinated a campaign between ground and space based observations. Our specific goal was to augment the ground based measurement of corona) prominence cavity temperatures made using iron lines in the IR (Habbal et al. 2010 ApJ 719 1362) with measurements performed by space based instruments. Included in the campaign were Hinode/EIS, XRT and SOT, PROBA2/SWAP, SDO/AIA, SOHO/CDS and STEREO/SECCHI/EUVI, in addition to the ground based IR measurements. We plan to use a combination of line ratio and forward modeling techniques to investigate the density and temperature structure of the cavities at that time.

A Strategic Roadmap to Centauri

NASA Technical Reports Server (NTRS)

Johnson, Les; Harris, David; Trausch, Ann; Matloff, Gregory L.; Taylor, Travis; Cutting, Kathleen

2005-01-01

This paper discusses the connectivity between in-space propulsion and in-space fabrication/repair and is based upon a workshop presentation by Les Johnson, manager of the In-Space Propulsion (ISP) Technology Project at NASA's Marshall Space Flight Center (MSFC) in Huntsville, Ala.. Technologies under study by ISP include aerocapture, advanced solar-electric propulsion, solar-thermal propulsion, advanced chemical propulsion, tethers and solar-photon sails. These propulsion systems are all approaching technology readiness levels (TRLs) at which they can be considered for application in space-science and exploration missions. Historically, human frontiers have expanded as people have learned to live off the land in new environments and to exploit local resorces. With this expansion, frontier settlements have required development of transportation improvements to carry tools and manufactured products to and from the frontier. It is demonstrated how ISP technologies will assist in the development of the solar-system frontier. In-space fabrication and repair will both require and assist the development of ISP propulsion systems, whether humans choose to settle planetary surfaces or to exploit resources of small Solar System bodies. As was true for successful terrestrial pioneers, in-space settlement and exploitation will require sophisticated surveys of inner and outer Solar System objects. ISP technologies will contribute to the success of these surveys, as well as to the efforts to retrieve Solar System resources. In a similar fashion, the utility of ISP products will be greatly enhanced by the technologies of in-space repair and fabrication. As in-space propulsion, fabrication and repair develop, human civilization may expand well beyond the Earth. In the future, small human communities (preceded by robotic explorers) may utilize these techniques to set sail f or the nearest stars.

A Strategic Roadmap to Centauri

NASA Astrophysics Data System (ADS)

Johnson, L.; Harris, D.; Trausch, A.; Matloff, G. L.; Taylor, T.; Cutting, K.

This paper discusses the connectivity between in-space propulsion and in-space fabrication/repair and is based upon a workshop presentation by Les Johnson, manager of the In-Space Propulsion (ISP) Technology Project at NASA's Marshall Space Flight Center (MSFC) in Huntsville, Alabama. Technologies under study by ISP include aerocapture, advanced solar- electric propulsion, solar-thermal propulsion, advanced chemical propulsion, tethers and solar-photon sails. These propulsion systems are all approaching technology readiness levels (TRLs) at which they can be considered for application in space- science and exploration missions. Historically, human frontiers have expanded as people have learned to “live-off-the-land” in new environments and to exploit local resources. With this expansion, frontier settlements have required development of transportation improvements to carry tools and manufactured products to and from the frontier. It is demonstrated how ISP technologies will assist in the development of the solar-system frontier. In-space fabrication and repair will both require and assist the development of ISP propulsion systems, whether humans choose to settle planetary surfaces or to exploit resources of small Solar System bodies. As was true for successful terrestrial pioneers, in-space settlement and exploitation will require sophisticated surveys of inner and outer Solar System objects. ISP technologies will contribute to the success of these surveys, as well as to the efforts to retrieve Solar System resources. In a similar fashion, the utility of ISP products will be greatly enhanced by the technologies of in-space repair and fabrication. As in-space propulsion, fabrication and repair develop, human civilization may expand well beyond the Earth. In the future, small human communities (preceded by robotic explorers) may utilize these techniques to set sail for the nearest stars.

Chart links solar, geophysical events with impacts on space technologies

NASA Astrophysics Data System (ADS)

Davenport, George R.

While developing a Space Weather Training Program for Air Force Space Command and the 50th Weather Squadron, both based in Colorado, ARINC Incorporated produced a flowchart that correlates solar and geophysical events with their impacts on Air Force systems.Personnel from both organizations collaborated in the development of the flowchart and provided many comments and suggestions. The model became the centerpiece of the Space Environment Impacts Reference Pamphlet, as well as the formal Space Weather Training Program. Although it is not a numerical or computer model, the flowchart became known as the “Space Environmental Impacts Model.”

Preface: MHD wave phenomena in the solar interior and atmosphere

NASA Astrophysics Data System (ADS)

Fedun, Viktor; Srivastava, A. K.

2018-01-01

The Sun is our nearest star and this star produces various plasma wave processes and energetic events. These phenomena strongly influence interplanetary plasma dynamics and contribute to space-weather. The understanding of solar atmospheric dynamics requires hi-resolution modern observations which, in turn, further advances theoretical models of physical processes in the solar interior and atmosphere. In particular, it is essential to connect the magnetohydrodynamic (MHD) wave processes with the small and large-scale solar phenomena vis-a-vis transport of energy and mass. With the advent of currently available and upcoming high-resolution space (e.g., IRIS, SDO, Hinode, Aditya-L1, Solar-C, Solar Orbiter), and ground-based (e.g., SST, ROSA, NLST, Hi-C, DKIST, EST, COSMO) observations, solar physicists are able to explore exclusive wave processes in various solar magnetic structures at different spatio-temporal scales.

Space-based solar power conversion and delivery systems study. Volume 2: Engineering analysis of orbital systems

NASA Technical Reports Server (NTRS)

1976-01-01

Program plans, schedules, and costs are determined for a synchronous orbit-based power generation and relay system. Requirements for the satellite solar power station (SSPS) and the power relay satellite (PRS) are explored. Engineering analysis of large solar arrays, flight mechanics and control, transportation, assembly and maintenance, and microwave transmission are included.

Space-based solar power conversion and delivery systems study

NASA Technical Reports Server (NTRS)

1976-01-01

Even at reduced rates of growth, the demand for electric power is expected to more than triple between now and 1995, and to triple again over the period 1995-2020. Without the development of new power sources and advanced transmission technologies, it may not be possible to supply electric energy at prices that are conductive to generalized economic welfare. Solar power is renewable and its conversion and transmission from space may be advantageous. The goal of this study is to assess the economic merit of space-based photovoltaic systems for power generation and a power relay satellite for power transmission. In this study, satellite solar power generation and transmission systems, as represented by current configurations of the Satellite Solar Station (SSPS) and the Power Relay Satellite (PRS), are compared with current and future terrestrial power generation and transmission systems to determine their technical and economic suitability for meeting power demands in the period of 1990 and beyond while meeting ever-increasing environmental and social constraints.

Multidirectional Cosmic Ray Ion Detector for Deep Space CubeSats

NASA Technical Reports Server (NTRS)

Wrbanek, John D.; Wrbanek, Susan Y.

2016-01-01

NASA Glenn Research Center has proposed a CubeSat-based instrument to study solar and cosmic ray ions in lunar orbit or deep space. The objective of Solar Proton Anisotropy and Galactic cosmic ray High Energy Transport Instrument (SPAGHETI) is to provide multi-directional ion data to further understand anisotropies in SEP and GCR flux.

Passivating Window/First Layer AR Coating for Space Solar Cells

NASA Technical Reports Server (NTRS)

Faur, Mircea; Faur, Maria; Bailey, S. G.; Flood, D. J.; Brinker, D. J.; Alterovitz, S. A.; Wheeler, D. R.; Matesscu, G.; Goradia, C.; Goradia, M.

2004-01-01

Chemically grown oxides, if well designed, offer excellent surface passivation of the emitter surface of space solar cells and can be used as effective passivating window/first layer AR coating. In this paper, we demonstrate the effectiveness of using a simple room temperature wet chemical technique to grow cost effective passivating layers on solar cell front surfaces after the front grid metallization step. These passivating layers can be grown both on planar and porous surfaces. Our results show that these oxide layers: (i) can effectively passivate the from the surface, (ii) can serve as an effective optical window/first layer AR coating, (iii) are chemically, thermally and UV stable, and (iv) have the potential of improving the BOL and especially the EOL efficiency of space solar cells. The potential of using this concept to simplify the III-V based space cell heterostructures while increasing their BOL and EOL efficiency is also discussed.

Solar Power Beaming: From Space to Earth

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rubenchik, A M; Parker, J M; Beach, R J

Harvesting solar energy in space and power beaming the collected energy to a receiver station on Earth is a very attractive way to help solve mankind's current energy and environmental problems. However, the colossal and expensive 'first step' required in achieving this goal has to-date stifled its initiation. In this paper, we will demonstrate that recent advance advances in laser and optical technology now make it possible to deploy a space-based system capable of delivering 1 MW of energy to a terrestrial receiver station, via a single unmanned commercial launch into Low Earth Orbit (LEO). Figure 1 depicts the overallmore » concept of our solar power beaming system, showing a large solar collector in space, beaming a coherent laser beam to a receiving station on Earth. We will describe all major subsystems and provide technical and economic discussion to support our conclusions.« less

Alternatives for Future U.S. Space-Launch Capabilities

DTIC Science & Technology

2006-10-01

directive issued on January 14, 2004—called the new Vision for Space Exploration (VSE)—set out goals for future exploration of the solar system using...of the solar system using manned spacecraft. Among those goals was a proposal to return humans to the moon no later than 2020. The ultimate goal...U.S. launch capacity exclude the Sea Launch system operated by Boeing in partnership with RSC- Energia (based in Moscow), Kvaerner ASA (based in Oslo

The Space Weather Modeling Framework (SWMF): Models and Validation

NASA Astrophysics Data System (ADS)

Gombosi, Tamas; Toth, Gabor; Sokolov, Igor; de Zeeuw, Darren; van der Holst, Bart; Ridley, Aaron; Manchester, Ward, IV

In the last decade our group at the Center for Space Environment Modeling (CSEM) has developed the Space Weather Modeling Framework (SWMF) that efficiently couples together different models describing the interacting regions of the space environment. Many of these domain models (such as the global solar corona, the inner heliosphere or the global magneto-sphere) are based on MHD and are represented by our multiphysics code, BATS-R-US. SWMF is a powerful tool for coupling regional models describing the space environment from the solar photosphere to the bottom of the ionosphere. Presently, SWMF contains over a dozen components: the solar corona (SC), eruptive event generator (EE), inner heliosphere (IE), outer heliosphere (OH), solar energetic particles (SE), global magnetosphere (GM), inner magnetosphere (IM), radiation belts (RB), plasmasphere (PS), ionospheric electrodynamics (IE), polar wind (PW), upper atmosphere (UA) and lower atmosphere (LA). This talk will present an overview of SWMF, new results obtained with improved physics as well as some validation studies.

Possibility of using sources of vacuum ultraviolet irradiation to solve problems of space material science

NASA Technical Reports Server (NTRS)

Verkhoutseva, E. T.; Yaremenko, E. I.

1974-01-01

An urgent problem in space materials science is simulating the interaction of vacuum ultraviolet (VUV) of solar emission with solids in space conditions, that is, producing a light source with a distribution that approximates the distribution of solar energy. Information is presented on the distribution of the energy flux of VUV of solar radiation. Requirements that must be satisfied by the VUV source used for space materials science are formulated, and a critical evaluation is given of the possibilities of using existing sources for space materials science. From this evaluation it was established that none of the sources of VUV satisfies the specific requirements imposed on the simulator of solar radiation. A solution to the problem was found to be in the development of a new type of source based on exciting a supersonic gas jet flowing into vacuum with a sense electron beam. A description of this gas-jet source, along with its spectral and operation characteristics, is presented.

Geometric shapes inversion method of space targets by ISAR image segmentation

NASA Astrophysics Data System (ADS)

Huo, Chao-ying; Xing, Xiao-yu; Yin, Hong-cheng; Li, Chen-guang; Zeng, Xiang-yun; Xu, Gao-gui

2017-11-01

The geometric shape of target is an effective characteristic in the process of space targets recognition. This paper proposed a method of shape inversion of space target based on components segmentation from ISAR image. The Radon transformation, Hough transformation, K-means clustering, triangulation will be introduced into ISAR image processing. Firstly, we use Radon transformation and edge detection to extract space target's main body spindle and solar panel spindle from ISAR image. Then the targets' main body, solar panel, rectangular and circular antenna are segmented from ISAR image based on image detection theory. Finally, the sizes of every structural component are computed. The effectiveness of this method is verified using typical targets' simulation data.

Evolution of the solar radius during the solar cycle 24 rise time

NASA Astrophysics Data System (ADS)

Meftah, Mustapha

2015-08-01

One of the real motivations to observe the solar radius is the suspicion that it might be variable. Possible temporal variations of the solar radius are important as an indicator of internal energy storage and as a mechanism for changes in the total solar irradiance. Measurements of the solar radius are of great interest within the scope of the debate on the role of the Sun in climate change. Solar energy input dominates the surface processes (climate, ocean circulation, wind, etc.) of the Earth. Thus, it appears important to know on what time scales the solar radius and other fundamental solar parameters, like the total solar irradiance, vary in order to better understand and assess the origin and mechanisms of the terrestrial climate changes. The current solar cycle is probably going to be the weakest in 100 years, which is an unprecedented opportunity for studying the variability of the solar radius during this period. This paper presents more than four years of solar radius measurements obtained with a satellite and a ground-based observatory during the solar cycle 24 rise time. Our measurements show the benefit of simultaneous measurements obtained from ground and space observatories. Space observations are a priori most favourable, however, space entails also technical challenges, a harsh environment, and a finite mission lifetime. The evolution of the solar radius during the rising phase of the solar cycle 24 show small variations that are out of phase with solar activity.

On-Orbit Measurement of Next Generation Space Solar Cell Technology on the International Space Station

NASA Technical Reports Server (NTRS)

Wolford, David S.; Myers, Matthew G.; Prokop, Norman F.; Krasowski, Michael J.; Parker, David S.; Cassidy, Justin C.; Davies, William E.; Vorreiter, Janelle O.; Piszczor, Michael F.; McNatt, Jeremiah S.

2015-01-01

Measurement is essential for the evaluation of new photovoltaic (PV) technology for space solar cells. NASA Glenn Research Center (GRC) is in the process of measuring several solar cells in a supplemental experiment on NASA Goddard Space Flight Center's (GSFC) Robotic Refueling Mission's (RRM) Task Board 4 (TB4). Four industry and government partners have provided advanced PV devices for measurement and orbital environment testing. The experiment will be on-orbit for approximately 18 months. It is completely self-contained and will provide its own power and internal data storage. Several new cell technologies including four- junction (4J) Inverted Metamorphic Multijunction (IMM) cells will be evaluated and the results compared to ground-based measurements.

Roles of Solar Power from Space for Europe - Space Exploration and Combinations with Terrestrial Solar Plant Concepts

NASA Astrophysics Data System (ADS)

Summerer, L.; Pipoli, T.; Galvez, A.; Ongaro, F.; Vasile, M.

The paper presents the prospective roles of SPS concepts for Europe, shows the outcome of recent studies undertaken by ESA's Advanced Concepts Team (ACT) together with European industry and research centres and gives insight into planned activities. The main focus is on the assessment of the principal validity and economic viability of solar power from space concepts in the light of advances in alternative sustainable, clean and potentially abundant solar-based terrestrial concepts. The paper takes into account expected changes in the European energy system (e.g. gradual introduction of hydrogen as energy vector). Special emphasis is given to the possibilities of integrating space and terrestrial solar plants. The relative geographic proximity of areas in North Africa with high average solar irradiation to the European energy consumer market puts Europe in a special position regarding the integration of space and terrestrial solar power concepts. The paper presents a method to optimise such an integration, taking into account different possible orbital constellations, terrestrial locations, plant number and sizes as well as consumer profiles and extends the scope from the European-only to a multi continental approach including the fast growing Chinese electricity market. The work intends to contribute to the discussion on long-term options for the European commitment to worldwide CO2 emission reduction. Cleaner electricity generation and environmentally neutral transport fuels (e.g. solar generated hydrogen) might be two major tools in reaching this goal.

MESSENGER Observations of Extreme Space Weather in Mercury's Magnetosphere

NASA Astrophysics Data System (ADS)

Slavin, J. A.

2013-09-01

Increasing activity on the Sun is allowing MESSENGER to make its first observations of Mercury's magnetosphere under extreme solar wind conditions. At Earth interplanetary shock waves and coronal mass ejections produce severe "space weather" in the form of large geomagnetic storms that affect telecommunications, space systems, and ground-based power grids. In the case of Mercury the primary effect of extreme space weather in on the degree to which this it's weak global magnetic field can shield the planet from the solar wind. Direct impact of the solar wind on the surface of airless bodies like Mercury results in space weathering of the regolith and the sputtering of atomic species like sodium and calcium to high altitudes where they contribute to a tenuous, but highly dynamic exosphere. MESSENGER observations indicate that during extreme interplanetary conditions the solar wind plasma gains access to the surface of Mercury through three main regions: 1. The magnetospheric cusps, which fill with energized solar wind and planetary ions; 2. The subsolar magnetopause, which is compressed and eroded by reconnection to very low altitudes where the natural gyro-motion of solar wind protons may result in their impact on the surface; 3. The magnetotail where hot plasma sheet ions rapidly convect sunward to impact the surface on the nightside of Mercury. The possible implications of these new MESSENGER observations for our ability to predict space weather at Earth and other planets will be described.

Solar and terrestrial physics. [effects of solar activities on earth environment

NASA Technical Reports Server (NTRS)

1975-01-01

The effects of solar radiation on the near space and biomental earth, the upper atmosphere, and the magnetosphere are discussed. Data obtained from the OSO satellites pertaining to the solar cycle variation of extreme ultraviolet (EUV) radiation are analyzed. The effects of solar cycle variation of the characteristics of the solar wind are examined. The fluid mechanics of shock waves and the specific relationship to the characteristics of solar shock waves are investigated. The solar and corpuscular heating of the upper atmosphere is reported based on the findings of the AEROS and NATE experiments. Seasonal variations of the upper atmosphere composition are plotted based on OGO-6 mass spectrometer data.

SOLAR CYCLE PROPAGATION, MEMORY, AND PREDICTION: INSIGHTS FROM A CENTURY OF MAGNETIC PROXIES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Munoz-Jaramillo, Andres; DeLuca, Edward E.; Dasi-Espuig, Maria

The solar cycle and its associated magnetic activity are the main drivers behind changes in the interplanetary environment and Earth's upper atmosphere (commonly referred to as space weather). These changes have a direct impact on the lifetime of space-based assets and can create hazards to astronauts in space. In recent years there has been an effort to develop accurate solar cycle predictions (with aims at predicting the long-term evolution of space weather), leading to nearly a hundred widely spread predictions for the amplitude of solar cycle 24. A major contributor to the disagreement is the lack of direct long-term databasesmore » covering different components of the solar magnetic field (toroidal versus poloidal). Here, we use sunspot area and polar faculae measurements spanning a full century (as our toroidal and poloidal field proxies) to study solar cycle propagation, memory, and prediction. Our results substantiate predictions based on the polar magnetic fields, whereas we find sunspot area to be uncorrelated with cycle amplitude unless multiplied by area-weighted average tilt. This suggests that the joint assimilation of tilt and sunspot area is a better choice (with aims to cycle prediction) than sunspot area alone, and adds to the evidence in favor of active region emergence and decay as the main mechanism of poloidal field generation (i.e., the Babcock-Leighton mechanism). Finally, by looking at the correlation between our poloidal and toroidal proxies across multiple cycles, we find solar cycle memory to be limited to only one cycle.« less

Survey of localized solar flare signatures in the ionosphere with GNSS, VLF, and GOES observations

NASA Astrophysics Data System (ADS)

Blevins, S. M.; Hayes, L.; Collado-Vega, Y. M.; Michael, B. P.; Noll, C. E.

2017-12-01

Global navigation satellite system (GNSS) phase measurements of the total electron content (TEC) and ionospheric delay are sensitive to sudden increases in electron density in the layers of the Earth's ionosphere. These sudden ionospheric disruptions, or SIDs, are due to enhanced X-ray and extreme ultraviolet radiation from a solar flare that drastically increases the electron density in localized regions. SIDs are solar flare signatures in the Earth's ionosphere and can be observed with very low frequency (VLF 3-30 kHz) monitors and dual-frequency GNSS (L1 = 1575.42 MHz, L2 = 1227.60 MHz) receivers that probe lower (D-region) to upper (F-region) ionospheric layers, respectively. Data from over 500 solar flare events, spanning April 2010 to July 2017, including GOES C-, M-, and X-class solar flares at various intensities, were collected from the Space Weather Database Of Notifications, Knowledge, Information (DONKI) developed at the NASA Goddard Space Flight Center (GSFC) Community Coordinated Modeling Center (CCMC). Historical GOES satellite (NOAA) X-ray flux (NASA GSFC CCMC integrated Space Weather Analysis system (iSWA)), and VLF SID (Stanford University Solar SID Space Weather Monitor program) time series data are available for all solar flare events of the sample set. We use GNSS data archived at the NASA GSFC Crustal Dynamics Data Information System (CDDIS) to characterize the F-region reactions to the increased ionization, complementing the ground-based D-region (VLF), and space-based X-ray observations (GOES). CDDIS provides GNSS data with 24-hour coverage at a temporal resolution of 30 seconds from over 500 stations. In our study we choose 63 stations, spanning 23 countries at a variety of geographic locations to provide continuous coverage for all solar flare events in the sample. This geographic distribution enables us to explore the effects of different solar flare intensities at localized regions in the Earths ionosphere around the globe. The GNSS observations are combined with VLF SID and GOES data to characterize and compare the impact of over 500 solar flare events through the upper and lower layers of the ionosphere. The sample set, data extraction and analysis methods, and preliminary results will be presented.

Solar Power from Space - Validation of Options for Europe

NASA Astrophysics Data System (ADS)

Summerer, L.; Ongaro, F.

2004-12-01

Solar power plants are among promising long-term energy options of the 21st century, covering humanities ever increasing energy need in a sustainable way free of greenhouse gas emission. Terrestrial solar power is one of the fastest growing energy sectors with high growth rates sustained over more than a decade and very promising forecasts. Since 30 years the idea of a large solar power plant in Earth orbit, transmitting energy to Earth-bound receiver sites enjoys periodic attention from energy and space entities. All studies concluded the principal technical feasibility of the concepts and gradually improved their power to mass ratio. No substantial development efforts were undertaken however since with current technology space generated electricity costs would still be too high, upfront costs prohibitive and the launcher sector not mature enough to reduce e/kg to orbit costs by the required order of magnitude. In the past space concepts were mainly compared to traditional energy systems. Based on this background, the Advanced Concepts Team (ACT) at the European Space Agency started a three-phased programme in 2003. The first phase of the programme, the Validation Phase, focussed on a comparison of space solar power plant with comparable terrestrial solutions on the one hand and the assessment of the potential of SPS for space exploration and space application on the other. The focus was mainly on Europe and should give an independent technical answer to the seemingly primitive question: "Why put power plants into space when there is so much sun in southern Europe and especially in the close-by North-African Sahara desert?". Space concepts were compared to terrestrial solutions based on equally advanced technology and equal economic conditions for the timeframe 2020/30 in terms of energy payback times, final e/kWh generation costs, adaptability to different energy scenarios, reliability and risk. Key words: ESA SPS Programme Plan; Strategy.

Numerical Study of Solar Storms from the Sun to Earth

NASA Astrophysics Data System (ADS)

Feng, Xueshang; Jiang, Chaowei; Zhou, Yufen

2017-04-01

As solar storms are sweeping the Earth, adverse changes occur in geospace environment. How human can mitigate and avoid destructive damages caused by solar storms becomes an important frontier issue that we must face in the high-tech times. It is of both scientific significance to understand the dynamic process during solar storm's propagation in interplanetary space and realistic value to conduct physics-based numerical researches on the three-dimensional process of solar storms in interplanetary space with the aid of powerful computing capacity to predict the arrival times, intensities, and probable geoeffectiveness of solar storms at the Earth. So far, numerical studies based on magnetohydrodynamics (MHD) have gone through the transition from the initial qualitative principle researches to systematic quantitative studies on concrete events and numerical predictions. Numerical modeling community has a common goal to develop an end-to-end physics-based modeling system for forecasting the Sun-Earth relationship. It is hoped that the transition of these models to operational use depends on the availability of computational resources at reasonable cost and that the models' prediction capabilities may be improved by incorporating the observational findings and constraints into physics-based models, combining the observations, empirical models and MHD simulations in organic ways. In this talk, we briefly focus on our recent progress in using solar observations to produce realistic magnetic configurations of CMEs as they leave the Sun, and coupling data-driven simulations of CMEs to heliospheric simulations that then propagate the CME configuration to 1AU, and outlook the important numerical issues and their possible solutions in numerical space weather modeling from the Sun to Earth for future research.

Sun-Burned: Space Weather's Impact on United States National Security

NASA Astrophysics Data System (ADS)

Stebbins, B.

2014-12-01

The heightened media attention surrounding the 2013-14 solar maximum presented an excellent opportunity to examine the ever-increasing vulnerability of US national security and its Department of Defense to space weather. This vulnerability exists for three principal reasons: 1) a massive US space-based infrastructure; 2) an almost exclusive reliance on an aging and stressed continental US power grid; and 3) a direct dependence upon a US economy adapted to the conveniences of space and uninterrupted power. I tailored my research and work for the national security policy maker and military strategists in an endeavor to initiate and inform a substantive dialogue on America's preparation for, and response to, a major solar event that would severely degrade core national security capabilities, such as military operations. Significant risk to the Department of Defense exists from powerful events that could impact its space-based infrastructure and even the terrestrial power grid. Given this ever-present and increasing risk to the United States, my work advocates raising the issue of space weather and its impacts to the level of a national security threat. With the current solar cycle having already peaked and the next projected solar maximum just a decade away, the government has a relatively small window to make policy decisions that prepare the nation and its Defense Department to mitigate impacts from these potentially catastrophic phenomena.

Fission Technology for Exploring and Utilizing the Solar System

NASA Technical Reports Server (NTRS)

Houts, Mike; VanDyke, Melissa; Godfroy, Tom; Pedersen, Kevin; Martin, James; Dickens, Ricky; Salvail, Pat; Hrbub, Ivana; Schmidt, George R. (Technical Monitor)

2000-01-01

Fission technology can enable rapid, affordable access to any point in the solar system. Potential fission-based transportation options include bimodal nuclear thermal rockets, high specific energy propulsion systems, and pulsed fission propulsion systems. In-space propellant re-supply enhances the effective performance of all systems, but requires significant infrastructure development. Safe, timely, affordable utilization of first-generation space fission propulsion systems will enable the development of more advanced systems. First generation space systems will build on over 45 years of US and international space fission system technology development to minimize cost,

Solar thematic maps for space weather operations

USGS Publications Warehouse

Rigler, E. Joshua; Hill, Steven M.; Reinard, Alysha A.; Steenburgh, Robert A.

2012-01-01

Thematic maps are arrays of labels, or "themes", associated with discrete locations in space and time. Borrowing heavily from the terrestrial remote sensing discipline, a numerical technique based on Bayes' theorem captures operational expertise in the form of trained theme statistics, then uses this to automatically assign labels to solar image pixels. Ultimately, regular thematic maps of the solar corona will be generated from high-cadence, high-resolution SUVI images, the solar ultraviolet imager slated to fly on NOAA's next-generation GOES-R series of satellites starting ~2016. These thematic maps will not only provide quicker, more consistent synoptic views of the sun for space weather forecasters, but digital thematic pixel masks (e.g., coronal hole, active region, flare, etc.), necessary for a new generation of operational solar data products, will be generated. This paper presents the mathematical underpinnings of our thematic mapper, as well as some practical algorithmic considerations. Then, using images from the Solar Dynamics Observatory (SDO) Advanced Imaging Array (AIA) as test data, it presents results from validation experiments designed to ascertain the robustness of the technique with respect to differing expert opinions and changing solar conditions.

Evaluation of installed solar systems at Navy, Army, and Air Force Bases. Final report, October 1984-September 1985

DOE Office of Scientific and Technical Information (OSTI.GOV)

Durlak, E.R.

1986-05-01

This report presents a summary of the results of site-evaluation inspection conducted at Navy, Army, and Air Force base. The solar systems evaluated included space heating, space cooling, and domestic hot water system. The systems range in size from small two-collector systems to large arrays installed on barracks, mess halls, office buildings, etc. These operational results are presented so that future designs will benefit from the lesson learned in this study.

Atomic Oxygen Durability Testing of an International Space Station Solar Array Validation Coupon

NASA Technical Reports Server (NTRS)

Forkapa, Mark J.; Stidham, Curtis; Banks, Bruce A.; Rutledge, Sharon K.; Ma, David H.; Sechkar, Edward A.

1996-01-01

An International Space Station solar array validation coupon was exposed in a directed atomic oxygen beam for space environment durability testing at the NASA Lewis Research Center. Exposure to atomic oxygen and intermittent tensioning of the solar array were conducted to verify the solar array#s durability to low Earth orbital atomic oxygen and to the docking threat of plume loading both of which are anticipated over its expected mission life of fifteen years. The validation coupon was mounted on a specially designed rotisserie. The rotisserie mounting enabled the solar and anti-solar facing side of the array to be exposed to directed atomic oxygen in a sweeping arrival process replicating space exposure. The rotisserie mounting also enabled tensioning, in order to examine the durability of the array and its hinge to simulated plume loads. Flash testing to verify electrical performance of the solar array was performed with a solar simulator before and after the exposure to atomic oxygen and tensile loading. Results of the flash testing indicated little or no degradation in the solar array#s performance. Photographs were also taken of the array before and after the durability testing and are included along with comparisons and discussions in this report. The amount of atomic oxygen damage appeared minor with the exception of a very few isolated defects. There were also no indications that the simulated plume loadings had weakened or damaged the array, even though there was some erosion of Kapton due to atomic oxygen attack. Based on the results of this testing, it is apparent that the International Space Station#s solar arrays should survive the low Earth orbital atomic oxygen environment and docking threats which are anticipated over its expected mission life.

GaAs/Ge solar panels for the SAMPEX program

NASA Technical Reports Server (NTRS)

Dobson, Rodney; Kukulka, Jerry; Dakermanji, George; Roufberg, Lew; Ahmad, Anisa; Lyons, John

1992-01-01

GaAs based solar cells have been developed for spacecraft use for several years. However, acceptance and application of these cells for spacecraft missions has been slow because of their high cost and concerns about their integration onto solar panels. Spectrolab has now completed fabrication of solar panels with GaAs/Ge solar cells for a second space program. This paper will focus on the design, fabrication and test of GaAs/Ge solar panels for the Solar Anomalous and Magnetospheric Particle Explorer (SAMPEX) Program.

Toroidal varied-line space (TVLS) gratings

NASA Astrophysics Data System (ADS)

Thomas, Roger J.

2003-02-01

It is a particular challenge to develop a stigmatic spectrograph for EUV wavelengths since the very low normal-incidence reflectance of standard materials most often requires that the design be restricted to a single optical element which must simultaneously provide both re-imaging and spectral dispersion. This problem has been solved in the past by the use of toroidal gratings with uniform line-space rulings (TULS). A number of solar EUV spectrographs have been based on such designs, including SOHO/CDS, Solar-B/EIS, and the sounding rockets SERTS and EUNIS. More recently, Kita, Harada, and collaborators have developed the theory of spherical gratings with varied line-space rulings (SVLS) operated at unity magnification, which have been flown on several astronomical satellite missions. These ideas are now combined into a spectrograph concept that considers varied-line space grooves ruled onto toroidal gratings. Such TVLS designs are found to provide excellent imaging even at very large spectrograph magnifications and beam-speeds, permitting extremely high-quality performance in remarkably compact instrument packages. Optical characteristics of two solar spectrographs based on this concept are described: SUMI, proposed as a sounding rocket experiment, and NEXUS, proposed for the Solar Dynamics Observatory mission.

Toroidal Varied-Line Space (TVLS) Gratings

NASA Technical Reports Server (NTRS)

Thomas, Roger J.; Oegerle, William (Technical Monitor)

2002-01-01

It is a particular challenge to develop a stigmatic spectrograph for XUV wavelengths since the very low normal-incidence reflectance of standard materials most often requires that the design be restricted to a single optical element which must simultaneously provide both re-imaging and spectral dispersion. This problem has been solved in the past by the use of toroidal gratings with uniform line-spaced rulings (TULS). A number of solar EUV (Extreme Ultraviolet) spectrometers have been based on such designs, including SOHO/CDS, Solar-B/EIS, and the sounding rockets SERTS and EUNIS. More recently, Kita, Harada, and collaborators have developed the theory of spherical gratings with varied line-space rulings (SVLS) operated at unity magnification, which have been flown on several astronomical satellite missions. We now combine these ideas into a spectrometer concept that puts varied-line space rulings onto toroidal gratings. Such TVLS designs are found to provide excellent imaging even at very large spectrograph magnifications and beam-speeds, permitting extremely high-quality performance in remarkably compact instrument packages. Optical characteristics of two solar spectrometers based on this concept are described: SUMI, proposed as a sounding rocket experiment, and NEXUS, proposed for the Solar Dynamics Observatory mission.

Prediction of the total cycle 24 of solar activity by several autoregressive methods and by the precursor method

NASA Astrophysics Data System (ADS)

Ozheredov, V. A.; Breus, T. K.; Obridko, V. N.

2012-12-01

As follows from the statement of the Third Official Solar Cycle 24 Prediction Panel created by the National Aeronautics and Space Administration (NASA), the National Oceanic and Atmospheric Administration (NOAA), and the International Space Environment Service (ISES) based on the results of an analysis of many solar cycle 24 predictions, there has been no consensus on the amplitude and time of the maximum. There are two different scenarios: 90 units and August 2012 or 140 units and October 2011. The aim of our study is to revise the solar cycle 24 predictions by a comparative analysis of data obtained by three different methods: the singular spectral method, the nonlinear neural-based method, and the precursor method. As a precursor for solar cycle 24, we used the dynamics of the solar magnetic fields forming solar spots with Wolf numbers Rz. According to the prediction on the basis of the neural-based approach, it was established that the maximum of solar cycle 24 is expected to be 70. The precursor method predicted 50 units for the amplitude and April of 2012 for the time of the maximum. In view of the fact that the data used in the precursor method were averaged over 4.4 years, the amplitude of the maximum can be 20-30% larger (i.e., around 60-70 units), which is close to the values predicted by the neural-based method. The protracted minimum of solar cycle 23 and predicted low values of the maximum of solar cycle 24 are reminiscent of the historical Dalton minimum.

A hybrid system for solar irradiance specification

NASA Astrophysics Data System (ADS)

Tobiska, W.; Bouwer, S.

2006-12-01

Space environment research and space weather operations require solar irradiances in a variety of time scales and spectral formats. We describe the development of solar irradiance characterization using four models and systems that are also used for space weather operations. The four models/systems include SOLAR2000 (S2K), SOLARFLARE (SFLR), APEX, and IDAR, which are used by Space Environment Technologies (SET) to provide solar irradiances from the soft X-rays through the visible spectrum. SFLR uses the GOES 0.1 0.8 nm X-rays in combination with a Mewe model subroutine to provide 0.1 30.0 nm irradiances at 0.1 nm spectral resolution, at 1 minute time resolution, and in a 6-hour XUV EUV spectral solar flare evolution forecast with a 7 minute latency and a 2 minute cadence. These irradiances have been calibrated with the SORCE XPS observations and we report on the inclusion of these irradiances into the S2K model. The APEX system is a real-time data retrieval system developed in conjunction with the University of Southern California Space Sciences Center (SSC) to provide SOHO SEM data processing and distribution. SSC provides the updated SEM data to the research community and SET provides the operational data to the space operations community. We describe how the SOHO SEM data, and especially the new S10.7 index, is being integrated directly into the S2K model for space weather operations. The IDAR system has been developed by SET to extract coronal hole boundaries, streamers, coronal loops, active regions, plage, network, and background (internetwork) features from solar images for comparison with solar magnetic features. S2K, SFLR, APEX, and IDAR outputs are integrated through the S2K solar irradiance platform that has become a hybrid system, i.e., a system that is able to produce irradiances using different processes, including empirical and physics-based models combined with real-time data integration.

Spacecraft Charging Current Balance Model Applied to High Voltage Solar Array Operations

NASA Technical Reports Server (NTRS)

Willis, Emily M.; Pour, Maria Z. A.

2016-01-01

Spacecraft charging induced by high voltage solar arrays can result in power losses and degradation of spacecraft surfaces. In some cases, it can even present safety issues for astronauts performing extravehicular activities. An understanding of the dominant processes contributing to spacecraft charging induced by solar arrays is important to current space missions, such as the International Space Station, and to any future space missions that may employ high voltage solar arrays. A common method of analyzing the factors contributing to spacecraft charging is the current balance model. Current balance models are based on the simple idea that the spacecraft will float to a potential such that the current collecting to the surfaces equals the current lost from the surfaces. However, when solar arrays are involved, these currents are dependent on so many factors that the equation becomes quite complicated. In order for a current balance model to be applied to solar array operations, it must incorporate the time dependent nature of the charging of dielectric surfaces in the vicinity of conductors1-3. This poster will present the factors which must be considered when developing a current balance model for high voltage solar array operations and will compare results of a current balance model with data from the Floating Potential Measurement Unit4 on board the International Space Station.

Development of an Ultraflex-Based Thin Film Solar Array for Space Applications

NASA Technical Reports Server (NTRS)

White, Steve; Douglas, Mark; Spence, Brian; Jones, P. Alan; Piszczor, Michael F.

2003-01-01

As flexible thin film photovoltaic (FTFPV) cell technology is developed for space applications, integration into a viable solar array structure that optimizes the attributes of this cell technology is critical. An advanced version of ABLE'sS UltraFlex solar array platform represents a near-term, low-risk approach to demonstrating outstanding array performance with the implementation of FTFPV technology. Recent studies indicate that an advanced UltraFlex solar array populated with 15% efficient thin film cells can achieve over 200 W/kg EOL. An overview on the status of hardware development and the future potential of this technology is presented.

Simulated Space Environmental Effects on Thin Film Solar Array Components

NASA Technical Reports Server (NTRS)

Finckenor, Miria; Carr, John; SanSoucie, Michael; Boyd, Darren; Phillips, Brandon

2017-01-01

The Lightweight Integrated Solar Array and Transceiver (LISA-T) experiment consists of thin-film, low mass, low volume solar panels. Given the variety of thin solar cells and cover materials and the lack of environmental protection typically afforded by thick coverglasses, a series of tests were conducted in Marshall Space Flight Center's Space Environmental Effects Facility to evaluate the performance of these materials. Candidate thin polymeric films and nitinol wires used for deployment were also exposed. Simulated space environment exposures were selected based on SSP 30425 rev. B, "Space Station Program Natural Environment Definition for Design" or AIAA Standard S-111A-2014, "Qualification and Quality Requirements for Space Solar Cells." One set of candidate materials were exposed to 5 eV atomic oxygen and concurrent vacuum ultraviolet (VUV) radiation for low Earth orbit simulation. A second set of materials were exposed to 1 MeV electrons. A third set of samples were exposed to 50, 100, 500, and 700 keV energy protons, and a fourth set were exposed to >2,000 hours of near ultraviolet (NUV) radiation. A final set was rapidly thermal cycled between -55 and +125 C. This test series provides data on enhanced power generation, particularly for small satellites with reduced mass and volume resources. Performance versus mass and cost per Watt is discussed.

Simulated Space Environmental Effects on Thin Film Solar Array Components

NASA Technical Reports Server (NTRS)

Finckenor, Miria; Carr, John; SanSoucie, Michael; Boyd, Darren; Phillips, Brandon

2017-01-01

The Lightweight Integrated Solar Array and Transceiver (LISA-T) experiment consists of thin-film, low mass, low volume solar panels. Given the variety of thin solar cells and cover materials and the lack of environmental protection typically afforded by thick coverglasses, a series of tests were conducted in Marshall Space Flight Center's Space Environmental Effects Facility to evaluate the performance of these materials. Candidate thin polymeric films and nitinol wires used for deployment were also exposed. Simulated space environment exposures were selected based on SSP 30425 rev. B, "Space Station Program Natural Environment Definition for Design" or AIAA Standard S-111A-2014, "Qualification and Quality Requirements for Space Solar Cells." One set of candidate materials were exposed to 5 eV atomic oxygen and concurrent vacuum ultraviolet (VUV) radiation for low Earth orbit simulation. A second set of materials were exposed to 1 MeV electrons. A third set of samples were exposed to 50, 100, 500, and 700 keV energy protons, and a fourth set were exposed to >2,000 hours of near ultraviolet (NUV) radiation. A final set was rapidly thermal cycled between -55 and +125degC. This test series provides data on enhanced power generation, particularly for small satellites with reduced mass and volume resources. Performance versus mass and cost per Watt is discussed.

Simulated Space Environmental Effects on Thin Film Solar Array Components

NASA Technical Reports Server (NTRS)

Finckenor, Miria; Carr, John; SanSoucie, Michael; Boyd, Darren; Phillips, Brandon

2017-01-01

The Lightweight Integrated Solar Array and Transceiver (LISA-T) experiment consists of thin-film, low mass, low volume solar panels. Given the variety of thin solar cells and cover materials and the lack of environmental protection afforded by typical thick coverglasses, a series of tests were conducted in Marshall Space Flight Center's Space Environmental Effects Facility to evaluate the performance of these materials. Candidate thin polymeric films and nitinol wires used for deployment were also exposed. Simulated space environment exposures were selected based on SSP 30425 rev. B, "Space Station Program Natural Environment Definition for Design" or AIAA Standard S-111A-2014, "Qualification and Quality Requirements for Space Solar Cells." One set of candidate materials were exposed to 5 eV atomic oxygen and concurrent vacuum ultraviolet (VUV) radiation for low Earth orbit simulation. A second set of materials were exposed to 1 MeV electrons. A third set of samples were exposed to 50, 500, and 750 keV energy protons, and a fourth set were exposed to >2,000 hours of ultraviolet radiation. A final set was rapidly thermal cycled between -50 and +120 C. This test series provides data on enhanced power generation, particularly for small satellites with reduced mass and volume resources. Performance versus mass and cost per Watt is discussed.

Space Qualification Test of a-Silicon Solar Cell Modules

NASA Technical Reports Server (NTRS)

Kim, Q.; Lawton, R. A.; Manion, S. J.; Okuno, J. O.; Ruiz, R. P.; Vu, D. T.; Vu, D. T.; Kayali, S. A.; Jeffrey, F. R.

2004-01-01

The basic requirements of solar cell modules for space applications are generally described in MIL-S-83576 for the specific needs of the USAF. However, the specifications of solar cells intended for use on space terrestrial applications are not well defined. Therefore, this qualifications test effort was concentrated on critical areas specific to the microseismometer probe which is intended to be included in the Mars microprobe programs. Parameters that were evaluated included performance dependence on: illuminating angles, terrestrial temperatures, lifetime, as well as impact landing conditions. Our qualification efforts were limited to these most critical areas of concern. Most of the tested solar cell modules have met the requirements of the program except the impact tests. Surprisingly, one of the two single PIN 2 x 1 amorphous solar cell modules continued to function even after the 80000G impact tests. The output power parameters, Pout, FF, Isc and Voc, of the single PIN amorphous solar cell module were found to be 3.14 mW, 0.40, 9.98 mA and 0.78 V, respectively. These parameters are good enough to consider the solar module as a possible power source for the microprobe seismometer. Some recommendations were made to improve the usefulness of the amorphous silicon solar cell modules in space terrestrial applications, based on the results obtained from the intensive short term lab test effort.

Determination of the Solar Energy Microclimate of the United States Using Satellite Data

NASA Technical Reports Server (NTRS)

Vonderharr, T. H.; Ellis, J. S.

1978-01-01

The determination of total solar energy reaching the ground over the United States using measurements from meteorological satellites as the basic data set is examined. The methods of satellite data processing are described. Uncertainty analysis and comparison of results with well calibrated surface pyranometers are used to estimate the probable error in the satellite-based determination of ground insolation. It is 10 to 15 percent for daily information, and about 5 percent for monthly values. However, the natural space and time variability of insolation is much greater than the uncertainty in the method. The most important aspect of the satellite-based technique is the ability to determine the solar energy reaching the ground over small areas where no other measurements are available. Thus, it complements the widely spaced solar radiation measurement network of ground stations.

150 kW Class Solar Electric Propulsion Spacecraft Power Architecture Model

NASA Technical Reports Server (NTRS)

Csank, Jeffrey T.; Aulisio, Michael V.; Loop, Benjamin

2017-01-01

The National Aeronautics and Space Administration (NASA) Solar Electric Propulsion Technology Demonstration Mission in conjunction with PC Krause and Associates has created a Simulink-based power architecture model for a 50 kilo-Watt (kW) solar electric propulsion system. NASA has extended this model to investigate 150 kW solar electric propulsion systems. Increasing the power system capability from 50 kW to 150 kW better aligns with the anticipated power requirements for Mars and other deep space explorations. The high-power solar electric propulsion capability has been identified as a critical part of NASAs future beyond-low-Earth-orbit for human-crewed exploration missions. This paper presents multiple 150 kW architectures, simulation results, and a discussion of their merits.

Solar Adaptive Optics.

PubMed

Rimmele, Thomas R; Marino, Jose

Adaptive optics (AO) has become an indispensable tool at ground-based solar telescopes. AO enables the ground-based observer to overcome the adverse effects of atmospheric seeing and obtain diffraction limited observations. Over the last decade adaptive optics systems have been deployed at major ground-based solar telescopes and revitalized ground-based solar astronomy. The relatively small aperture of solar telescopes and the bright source make solar AO possible for visible wavelengths where the majority of solar observations are still performed. Solar AO systems enable diffraction limited observations of the Sun for a significant fraction of the available observing time at ground-based solar telescopes, which often have a larger aperture than equivalent space based observatories, such as HINODE. New ground breaking scientific results have been achieved with solar adaptive optics and this trend continues. New large aperture telescopes are currently being deployed or are under construction. With the aid of solar AO these telescopes will obtain observations of the highly structured and dynamic solar atmosphere with unprecedented resolution. This paper reviews solar adaptive optics techniques and summarizes the recent progress in the field of solar adaptive optics. An outlook to future solar AO developments, including a discussion of Multi-Conjugate AO (MCAO) and Ground-Layer AO (GLAO) will be given. Supplementary material is available for this article at 10.12942/lrsp-2011-2.

Implementation of a Space Weather VOEvent service at IRAP in the frame of Europlanet H2020 PSWS

NASA Astrophysics Data System (ADS)

Gangloff, M.; André, N.; Génot, V.; Cecconi, B.; Le Sidaner, P.; Bouchemit, M.; Budnik, E.; Jourdane, N.

2017-09-01

Under Horizon 2020, the Europlanet Research Infrastructure includes PSWS (Planetary Space Weather Services), a set of new services that extend the concepts of space weather and space situation awareness to other planets of our solar system. One of these services is an Alert service associated in particular with an heliospheric propagator tool for solar wind predictions at planets, a meteor shower prediction tool, and a cometary tail crossing prediction tool. This Alert service, is based on VOEvent, an international standard proposed by the IVOA and widely used by the astronomy community. The VOEvent standard provides a means of describing transient celestial events in a machine-readable format. VOEvent is associated with VTP, the VOEvent Transfer Protocol that defines the system by which VOEvents may be disseminated to the community This presentation will focus on the enhancements of the VOEvent standard necessary to take into account the needs of the Solar System community and Comet, a freely available and open source implementation of VTP used by PSWS for its Alert service. Comet is implemented by several partners of PSWS, including IRAP and Observatoire de Paris. A use case will be presented for the heliospheric propagator tool based on extreme solar wind pressure pulses predicted at planets and probes from a 1D MHD model and real time observations of solar wind parameters.

New solar irradiances for use in space research

NASA Astrophysics Data System (ADS)

Tobiska, W.; Bouwer, D.; Jones, A.

Space environment research applications require solar irradiances in a variety of time scales and spectral formats We describe the development of research grade modeled solar irradiances using four models and systems that are also used for space weather operations The four models systems include SOLAR2000 S2K SOLARFLARE SFLR APEX and IDAR which are used by Space Environment Technologies SET to provide solar irradiances from the soft X-rays through the visible spectrum SFLR uses the GOES 0 1--0 8 nm X-rays in combination with a Mewe model subroutine to provide 0 1--30 0 nm irradiances at 0 1 nm spectral resolution at 1 minute time resolution and in a 6-hour XUV--EUV spectral solar flare evolution forecast with a 7 minute latency and a 2 minute cadence These irradiances have been calibrated with the SORCE XPS observations and we report on the inclusion of these irradiances in the S2K model There are additional developments with S2K that we discuss particularly the method by which S2K is emerging as a hybrid model empirical plus physics-based and real-time data integration platform Numerous new solar indices have been recently developed for the operations community and we describe their inclusion in S2K The APEX system is a real-time data retrieval system developed under contract to the University of Southern California Space Sciences Center SSC to provide SOHO SEM data processing and distribution SSC provides the updated SEM data to the research community and SET provides the operational data to the space operations community We

High Resolution Mass Spectrometry for future space instrumentation : current development within the French Space Orbitrap Consortium

NASA Astrophysics Data System (ADS)

Briois, Christelle; Lebreton, Jean-Pierre; Szopa, Cyril; Thirkell, Laurent; Aradj, Kenzi; Bouabdellah, Abdel; Boukrara, Amirouche; Carrasco, Nathalie; Chalumeau, Gilles; Chapelon, Olivier; Colin, Fabrice; Cottin, Hervé; Engrand, Cécile; Grand, Noel; Kukui, Alexandre; Pennanech, Cyril; Thissen, Roland; Vuitton, Véronique; Zapf, Pascal; Makarov, Alexander

2014-05-01

Mass spectrometry has been used for years in space exploration to characterise the chemical composition of solar system bodies and their environment. Because of the harsh constraints imposed to the space probe instruments, their mass resolution is quite limited compared to laboratory instruments, sometimes leading to significant limitations in the treatment of the data collected with this type of instrumentation. Future in situ solar system exploration missions would significantly benefit from High Resolution Mass Spectrometry (HRMS). For a few years, 5 French laboratories (LPC2E, IPAG, LATMOS, LISA, CSNSM) involved in the chemical investigation of solar system bodies formed a Consortium to develop HRMS for future space exploration, based on the use of the Orbitrap technology (C. Briois et al., 2014, to be submitted). This development is carried out in the frame of a Research and Technology (R&T) development programme partly funded by the French Space Agency (CNES). The work is undertaken in close collaboration with the Thermo Fisher Scientific Company, which commercialises Orbitrap-based laboratory instruments. The R&T activities are currently concentrating on the core elements of the Orbitrap analyser that are required to reach a sufficient maturity level for allowing design studies of future space instruments. We are indeed pursuing, within international collaborations, the definition of several instrument concepts based on the core elements that are subject of our R&T programme. In this talk, we briefly discuss science applications for future orbitrap-based HRMS space instruments. We highlight present results of our R&T programme.

Chemical aspects of the formation of the solar system

NASA Technical Reports Server (NTRS)

Arrhenius, G.

1978-01-01

Application of Alfven's theory for the formation of the solar system and the constraints imposed by the chemical composition of space materials are discussed with reference to chemical processes involved in the formation of the solar system. Evidence for the chemical properties of the space medium and the chemical consequences of the postulated physical differentiation processes are outlined, and interpretations based on structure and composition of meteorite material are indicated. A large range of topics, including processes involving chemical differentiation, temperature effects, and isotope fractionation, are examined.

Satellite Power System. Concept development and evaluation program, volume 6: Construction and operations

NASA Technical Reports Server (NTRS)

Benson, H.; Jenkins, L. M.

1981-01-01

The construction, operation, and maintenance requirements for a solar power satellite, including the space and ground systems, are reviewed. The basic construction guidelines are explained, and construction location options are discussed. The space construction tasks, equipment, and base configurations are discussed together with the operations required to place a solar power satellite in geosynchronous orbit. A rectenna construction technique is explained, and operation with the grid is defined. Maintenance requirements are summarized for the entire system. Key technology issues required for solar power satellite construction operations are defined.

Model for Solar Proton Risk Assessment

NASA Technical Reports Server (NTRS)

Xapos, M. A.; Stauffer, C.; Gee, G. B.; Barth, J. L.; Stassinopoulos, E. G.; McGuire, R. E.

2004-01-01

A statistical model for cumulative solar proton event fluences during space missions is presented that covers both the solar minimum and solar maximum phases of the solar cycle. It is based on data from the IMP and GOES series of satellites that is integrated together to allow the best features of each data set to be taken advantage of. This allows fluence-energy spectra to be extended out to energies of 327 MeV.

Solar Air Collectors: How Much Can You Save?

DOE R&D Accomplishments Database

Newburn, J. D.

1985-04-01

A collector efficiency curve is used to determine the output of solar air collectors based on the testing of seven solar collectors sold in Iowa. In this application the solar heater is being used as a space heater for a house. The performance of the solar air heater was analyzed and an 8% savings in energy was achieved over a one year period using two 4 x 8 collectors in a typical house.

KSC-08pd2410

NASA Image and Video Library

2008-07-30

VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, technicians follow the movement of NASA's Interstellar Boundary Explorer, or IBEX, mission spacecraft toward the mobile stand in the foreground. The IBEX satellite will make the first map of the boundary between the Solar System and interstellar space. IBEX is the first mission designed to detect the edge of the Solar System. As the solar wind from the sun flows out beyond Pluto, it collides with the material between the stars, forming a shock front. IBEX contains two neutral atom imagers designed to detect particles from the termination shock at the boundary between the Solar System and interstellar space. IBEX also will study galactic cosmic rays, energetic particles from beyond the Solar System that pose a health and safety hazard for humans exploring beyond Earth orbit. IBEX will make these observations from a highly elliptical orbit that takes it beyond the interference of the Earth's magnetosphere. IBEX is targeted for launch from the Pegasus XL rocket on Oct. 5. Photo credit: NASA

KSC-08pd2409

NASA Image and Video Library

2008-07-30

VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, technicians prepare a mobile stand to receive NASA's Interstellar Boundary Explorer, or IBEX, mission spacecraft. The IBEX satellite will make the first map of the boundary between the Solar System and interstellar space. IBEX is the first mission designed to detect the edge of the Solar System. As the solar wind from the sun flows out beyond Pluto, it collides with the material between the stars, forming a shock front. IBEX contains two neutral atom imagers designed to detect particles from the termination shock at the boundary between the Solar System and interstellar space. IBEX also will study galactic cosmic rays, energetic particles from beyond the Solar System that pose a health and safety hazard for humans exploring beyond Earth orbit. IBEX will make these observations from a highly elliptical orbit that takes it beyond the interference of the Earth's magnetosphere. IBEX is targeted for launch from the Pegasus XL rocket on Oct. 5. Photo credit: NASA

Solar Seismology from Space. a Conference at Snowmass, Colorado

NASA Technical Reports Server (NTRS)

Ulrich, R. K.; Harvey, J.; Rhodes, E. J., Jr.; Toomre, J.

1984-01-01

The quality of the ground based observing environment suffers from several degrading factors: diurnal interruptions and thermal variations, atmospheric seeing and transparency fluctuations and adverse weather interruptions are among the chief difficulties. The limited fraction of the solar surface observable from only one vantage point is also a potential limitation to the quality of the data available without going to space. Primary conference goals were to discuss in depth the scientific return from current observations and analyses of solar oscillations, to discuss the instrumental and site requirements for realizing the full potential of the seismic analysis method, and to help bring new workers into the field by collecting and summarizing the key background theory. At the conclusion of the conference there was a clear consensus that ground based observation would not be able to provide data of the quality required to permit a substantial analysis of the solar convection zone dynamics or to permit a full deduction of the solar interior structure.

What Properties of CMEs are Most Important for Space Weather?

NASA Technical Reports Server (NTRS)

Gopalswamy, Nat

2012-01-01

Severe space weather is characterized by intense particle radiation from the Sun and major geomagnetic storm caused by magnetized solar plasmas arriving at Earth. Coronal mass ejections (CMEs) are key players in both these aspects. CMEs traveling at super-Alfv nic speeds drive fast-mode MHD shocks that create the high levels of particle radiation. When a CME arrives at Earth, the CME-associated magnetic fields reconnect with Earth s magnetopause fields resulting in solar plasma entry into the magnetosphere and a geomagnetic storm depending on the magnetic structure of the CME. Particle radiation starts affecting geospace as soon as the CMEs leave the Sun and the geospace may be immersed in the radiation for several days. On the other hand, the geomagnetic storm happens only upon CME arrival at Earth. The requirements for the production of particles and magnetic storms by CMEs are different in a number of respects: solar source location, CME magnetic structure, conditions in the ambient solar wind, and shock-driving ability of CMEs. Intense shocks arriving at Earth have additional space weather effects such as sudden impulse that shrinks the magnetosphere often exposing satellites in geosynchronous orbit to the solar wind and energetic storm particle events. This paper highlights these space weather effects using CME observations space and ground based instruments during of solar cycles 23 and 24.

Optical disk processing of solar images.

NASA Astrophysics Data System (ADS)

Title, A.; Tarbell, T.

The current generation of space and ground-based experiments in solar physics produces many megabyte-sized image data arrays. Optical disk technology is the leading candidate for convenient analysis, distribution, and archiving of these data. The authors have been developing data analysis procedures which use both analog and digital optical disks for the study of solar phenomena.

Effects of solar activity in the middle atmosphere dynamical regime over Eastern Siberia, USSR

NASA Technical Reports Server (NTRS)

Gaidukov, V. A.; Kazimirovsky, E. S.; Zhovty, E. I.; Chernigovskaya, M. A.

1989-01-01

Lower thermospheric (90 to 120 km) wind data was acquired by ground based spaced-receiver method (HF, LF) near Irkutsk (52 deg N, 104 deg E). There is interrelated solar and meteorological control of lower thermosphere dynamics. Some features of solar control effects on the wind parameters are discussed.

MIC-Large Scale Magnetically Inflated Cable Structures for Space Power, Propulsion, Communications and Observational Applications

NASA Astrophysics Data System (ADS)

Powell, James; Maise, George; Rather, John

2010-01-01

A new approach for the erection of rigid large scale structures in space-MIC (Magnetically Inflated Cable)-is described. MIC structures are launched as a compact payload of superconducting cables and attached tethers. After reaching orbit, the superconducting cables are energized with electrical current. The magnet force interactions between the cables cause them to expand outwards into the final large structure. Various structural shapes and applications are described. The MIC structure can be a simple flat disc with a superconducting outer ring that supports a tether network holding a solar cell array, or it can form a curved mirror surface that concentrates light and focuses it on a smaller region-for example, a high flux solar array that generates electric power, a high temperature receiver that heats H2 propellant for high Isp propulsion, and a giant primary reflector for a telescope for astronomy and Earth surveillance. Linear dipole and quadrupole MIC structures are also possible. The linear quadrupole structure can be used for magnetic shielding against cosmic radiation for astronauts, for example. MIC could use lightweight YBCO superconducting HTS (High Temperature Superconductor) cables, that can operate with liquid N2 coolant at engineering current densities of ~105 amp/cm2. A 1 kilometer length of MIC cable would weigh only 3 metric tons, including superconductor, thermal insulations, coolant circuits, and refrigerator, and fit within a 3 cubic meter compact package for launch. Four potential MIC applications are described: Solar-thermal propulsion using H2 propellant, space based solar power generation for beaming power to Earth, a large space telescope, and solar electric generation for a manned lunar base. The first 3 applications use large MIC solar concentrating mirrors, while the 4th application uses a surface based array of solar cells on a magnetically levitated MIC structure to follow the sun. MIC space based mirrors can be very large and light in weight. A 300 meter diameter MIC mirror in orbit for example, would weigh 20 metric tons and MIC structures can be easily developed and tested on Earth at small scale in existing evacuated chambers followed by larger scale tests in the atmosphere, using a vacuum tight enclosure on the small diameter superconducting cable to prevent air leakage into the evacuated thermal insulation around the superconducting cable.

Highlights from the First Ever Demographic Study of Solar Physics, Space Physics, and Upper Atmospheric Physics

NASA Astrophysics Data System (ADS)

Moldwin, M.; Morrow, C. A.; White, S. C.; Ivie, R.

2014-12-01

Members of the Education & Workforce Working Group and the American Institute of Physics (AIP) conducted the first ever National Demographic Survey of working professionals for the 2012 National Academy of Sciences Solar and Space Physics Decadal Survey to learn about the demographics of this sub-field of space science. The instrument contained questions for participants on: the type of workplace; basic demographic information regarding gender and minority status, educational pathways (discipline of undergrad degree, field of their PhD), how their undergraduate and graduate student researchers are funded, participation in NSF and NASA funded spaceflight missions and suborbital programs, and barriers to career advancement. Using contact data bases from AGU, the American Astronomical Society's Solar Physics Division (AAS-SPD), attendees of NOAA's Space Weather Week and proposal submissions to NSF's Atmospheric, Geospace Science Division, the AIP's Statistical Research Center cross correlated and culled these data bases resulting in 2776 unique email addresses of US based working professionals. The survey received 1305 responses (51%) and generated 125 pages of single space answers to a number of open-ended questions. This talk will summarize the highlights of this first-ever demographic survey including findings extracted from the open-ended responses regarding barriers to career advancement which showed significant gender differences.

High-Power Solar Electric Propulsion for Future NASA Missions

NASA Technical Reports Server (NTRS)

Manzella, David; Hack, Kurt

2014-01-01

NASA has sought to utilize high-power solar electric propulsion as means of improving the affordability of in-space transportation for almost 50 years. Early efforts focused on 25 to 50 kilowatt systems that could be used with the Space Shuttle, while later efforts focused on systems nearly an order of magnitude higher power that could be used with heavy lift launch vehicles. These efforts never left the concept development phase in part because the technology required was not sufficiently mature. Since 2012 the NASA Space Technology Mission Directorate has had a coordinated plan to mature the requisite solar array and electric propulsion technology needed to implement a 30 to 50 kilowatt solar electric propulsion technology demonstration mission. Multiple solar electric propulsion technology demonstration mission concepts have been developed based on these maturing technologies with recent efforts focusing on an Asteroid Redirect Robotic Mission. If implemented, the Asteroid Redirect Vehicle will form the basis for a capability that can be cost-effectively evolved over time to provide solar electric propulsion transportation for a range of follow-on mission applications at power levels in excess of 100 kilowatts.

Feasibility study of an image slicer for future space application

NASA Astrophysics Data System (ADS)

Calcines, A.; Ichimoto, K.

2014-08-01

This communication presents the feasibility study of an image slicer for future space missions, especially for the integral field unit (IFU) of the SUVIT (Solar UV-Visible-IR telescope) spectro-polarimeter on board the Japanese-led solar space mission Solar-C as a backup option. The MuSICa (Multi-Slit Image slicer based on collimator-Camera) image slicer concept, originally developed for the European Solar Telescope, has been adapted to the SUVIT requirements. The IFU will reorganizes a 2-D field of view of 10 x 10 arcsec2 into three slits of 0.18 arcsec width by 185.12 arcsec length using flat slicer mirrors of 100 μm width. The layout of MuSICa for Solar-C is telecentric and offers an optical quality limited by diffraction. The entrance for the SUVIT spectro-polarimeter is composed by the three IFU slits and one ordinal long slit to study, using high resolution spectro-polarimetry, the solar atmosphere (Photosphere and Chromosphere) within a spectral range between 520 nm (optionally 280 nm) and 1,100 nm.

A Smoothed Eclipse Model for Solar Electric Propulsion Trajectory Optimization

NASA Technical Reports Server (NTRS)

Aziz, Jonathan D.; Scheeres, Daniel J.; Parker, Jeffrey S.; Englander, Jacob A.

2017-01-01

Solar electric propulsion (SEP) is the dominant design option for employing low-thrust propulsion on a space mission. Spacecraft solar arrays power the SEP system but are subject to blackout periods during solar eclipse conditions. Discontinuity in power available to the spacecraft must be accounted for in trajectory optimization, but gradient-based methods require a differentiable power model. This work presents a power model that smooths the eclipse transition from total eclipse to total sunlight with a logistic function. Example trajectories are computed with differential dynamic programming, a second-order gradient-based method.

Ultra-Lightweight Hybrid Thin-Film Solar Cells: A Survey of Enabling Technologies for Space Power Applications

NASA Technical Reports Server (NTRS)

Hepp, Aloysius F.; McNatt, Jeremiah S.; Bailey, Sheila G.; Dickman, John E.; Raffaelle, Ryne P.; Landi, Brian J.; Anctil, Annick; DiLeo, Roberta; Jin, Michael H.-C.; Lee, Chung-Young;

Predicting space climate change

NASA Astrophysics Data System (ADS)

Balcerak, Ernie

2011-10-01

Galactic cosmic rays and solar energetic particles can be hazardous to humans in space, damage spacecraft and satellites, pose threats to aircraft electronics, and expose aircrew and passengers to radiation. A new study shows that these threats are likely to increase in coming years as the Sun approaches the end of the period of high solar activity known as “grand solar maximum,” which has persisted through the past several decades. High solar activity can help protect the Earth by repelling incoming galactic cosmic rays. Understanding the past record can help scientists predict future conditions. Barnard et al. analyzed a 9300-year record of galactic cosmic ray and solar activity based on cosmogenic isotopes in ice cores as well as on neutron monitor data. They used this to predict future variations in galactic cosmic ray flux, near-Earth interplanetary magnetic field, sunspot number, and probability of large solar energetic particle events. The researchers found that the risk of space weather radiation events will likely increase noticeably over the next century compared with recent decades and that lower solar activity will lead to increased galactic cosmic ray levels. (Geophysical Research Letters, doi:10.1029/2011GL048489, 2011)

Direct glass bonded high specific power silicon solar cells for space applications

NASA Technical Reports Server (NTRS)

Dinetta, L. C.; Rand, J. A.; Cummings, J. R.; Lampo, S. M.; Shreve, K. P.; Barnett, Allen M.

1991-01-01

A lightweight, radiation hard, high performance, ultra-thin silicon solar cell is described that incorporates light trapping and a cover glass as an integral part of the device. The manufacturing feasibility of high specific power, radiation insensitive, thin silicon solar cells was demonstrated experimentally and with a model. Ultra-thin, light trapping structures were fabricated and the light trapping demonstrated experimentally. The design uses a micro-machined, grooved back surface to increase the optical path length by a factor of 20. This silicon solar cell will be highly tolerant to radiation because the base width is less than 25 microns making it insensitive to reduction in minority carrier lifetime. Since the silicon is bonded without silicone adhesives, this solar cell will also be insensitive to UV degradation. These solar cells are designed as a form, fit, and function replacement for existing state of the art silicon solar cells with the effect of simultaneously increasing specific power, power/area, and power supply life. Using a 3-mil thick cover glass and a 0.3 g/sq cm supporting Al honeycomb, a specific power for the solar cell plus cover glass and honeycomb of 80.2 W/Kg is projected. The development of this technology can result in a revolutionary improvement in high survivability silicon solar cell products for space with the potential to displace all existing solar cell technologies for single junction space applications.

150 kW Class Solar Electric Propulsion Spacecraft Power Architecture Model

NASA Technical Reports Server (NTRS)

Csank, Jeffrey T.; Aulisio, Michael V.; Loop, Benjamin

2017-01-01

The National Aeronautics and Space Administration (NASA) Solar Electric Propulsion Technology Demonstration Mission (SEP TDM), in conjunction with PC Krause and Associates, has created a Simulink-based power architecture model for a 50 kilo-Watt (kW) solar electric propulsion system. NASA has extended this model to investigate 150 kW solar electric propulsion systems. Increasing the power capability to 150 kW is an intermediate step to the anticipated power requirements for Mars and other deep space applications. The high-power solar electric propulsion capability has been identified as a critical part of NASA’s future beyond-low-Earth-orbit for human-crewed exploration missions. This paper presents four versions of a 150 kW architecture, simulation results, and a discussion of their merits.

Effects of solar ultraviolet radiations on Bacillus subtilis spores and T-7 bacteriophage

NASA Technical Reports Server (NTRS)

Spizizen, J.; Isherwood, J. E.; Taylor, G. R.

1975-01-01

Spores of Bacillus subtilis HA 101 and the DNA polymerase I-defective mutant HA 101 (59)F were exposed to selected wavelengths of solar ultraviolet light and space vacuum during the return of Apollo 16. In addition, coliphage T-7 suspensions were exposed to solar ultraviolet radiation as part of the Microbial Response to Space Environment Experiment. Optical filters were employed to provide different energy levels at wavelengths 254 nm and 280 nm. Dose-response curves for lethal and mutagenic effects were compared with ground-based data. A close parallel was observed between the results of solar radiation and ground tests with spores of the two strains. However, significantly greater inactivation of T-7 bacteriophage was observed after exposure to solar ultraviolet radiation.

Solar System Observations with the James Webb Space Telescope

NASA Technical Reports Server (NTRS)

Norwood, James; Hammel, Heidi; Milam, Stefanie; Stansberry, John; Lunine, Jonathan; Chanover, Nancy; Hines, Dean; Sonneborn, George; Tiscareno, Matthew; Brown, Michael;

NASA Glenn Research Center Solar Cell Experiment Onboard the International Space Station

NASA Technical Reports Server (NTRS)

Myers, Matthew G.; Wolford, David S.; Prokop, Norman F.; Krasowski, Michael J.; Parker, David S.; Cassidy, Justin C.; Davies , William E.; Vorreiter, Janelle O.; Piszczor, Michael F.; Mcnatt, Jeremiah S.;

An analysis of interplanetary space radiation exposure for various solar cycles

NASA Technical Reports Server (NTRS)

Badhwar, G. D.; Cucinotta, F. A.; O'Neill, P. M.; Wilson, J. W. (Principal Investigator)

1994-01-01

The radiation dose received by crew members in interplanetary space is influenced by the stage of the solar cycle. Using the recently developed models of the galactic cosmic radiation (GCR) environment and the energy-dependent radiation transport code, we have calculated the dose at 0 and 5 cm water depth; using a computerized anatomical man (CAM) model, we have calculated the skin, eye and blood-forming organ (BFO) doses as a function of aluminum shielding for various solar minima and maxima between 1954 and 1989. These results show that the equivalent dose is within about 15% of the mean for the various solar minima (maxima). The maximum variation between solar minimum and maximum equivalent dose is about a factor of three. We have extended these calculations for the 1976-1977 solar minimum to five practical shielding geometries: Apollo Command Module, the least and most heavily shielded locations in the U.S. space shuttle mid-deck, center of the proposed Space Station Freedom cluster and sleeping compartment of the Skylab. These calculations, using the quality factor of ICRP 60, show that the average CAM BFO equivalent dose is 0.46 Sv/year. Based on an approach that takes fragmentation into account, we estimate a calculation uncertainty of 15% if the uncertainty in the quality factor is neglected.

Human Exploration of the Solar System by 2100

NASA Technical Reports Server (NTRS)

Litchford, Ronald J.

2017-01-01

It has been suggested that the U.S., in concert with private entities and international partners, set itself on a course to accomplish human exploration of the solar system by the end of this century. This is a strikingly bold vision intended to revitalize the aspirations of HSF in service to the security, economic, and scientific interests of the nation. Solar system distance and time scales impose severe requirements on crewed space transportation systems, however, and fully realizing all objectives in support of this goal will require a multi-decade commitment employing radically advanced technologies - most prominently, space habitats capable of sustaining and protecting life in harsh radiation environments under zero gravity conditions and in-space propulsion technologies capable of rapid deep space transits with earth return, the subject of this paper. While near term mission destinations such as the moon and Mars can be accomplished with chemical propulsion and/or high power SEP, fundamental capability constraints render these traditional systems ineffective for solar system wide exploration. Nuclear based propulsion and alternative energetic methods, on the other hand, represent potential avenues, perhaps the only viable avenues, to high specific power space transport evincing reduced trip time, reduced IMLEO, and expanded deep space reach. Here, very long term HSF objectives for solar system wide exploration are examined in relation to the advanced propulsion technology solution landscape including foundational science, technical/engineering challenges, and developmental prospects.

The NASA Lewis Research Center program in space solar cell research and technology. [efficient silicon solar cell development program

NASA Technical Reports Server (NTRS)

Brandhorst, H. W., Jr.

1979-01-01

Progress in space solar cell research and technology is reported. An 18 percent-AMO-efficient silicon solar cell, reduction in the radiation damage suffered by silicon solar cells in space, and high efficiency wrap-around contact and thin (50 micrometer) coplanar back contact silicon cells are among the topics discussed. Reduction in the cost of silicon cells for space use, cost effective GaAs solar cells, the feasibility of 30 percent AMO solar energy conversion, and reliable encapsulants for space blankets are also considered.

Space Station on-orbit solar array loads during assembly

NASA Astrophysics Data System (ADS)

Ghofranian, S.; Fujii, E.; Larson, C. R.

This paper is concerned with the closed-loop dynamic analysis of on-orbit maneuvers when the Space Shuttle is fully mated to the Space Station Freedom. A flexible model of the Space Station in the form of component modes is attached to a rigid orbiter and on-orbit maneuvers are performed using the Shuttle Primary Reaction Control System jets. The traditional approach for this type of problems is to perform an open-loop analysis to determine the attitude control system jet profiles based on rigid vehicles and apply the resulting profile to a flexible Space Station. In this study a closed-loop Structure/Control model was developed in the Dynamic Analysis and Design System (DADS) program and the solar array loads were determined for single axis maneuvers with various delay times between jet firings. It is shown that the Digital Auto Pilot jet selection is affected by Space Station flexibility. It is also shown that for obtaining solar array loads the effect of high frequency modes cannot be ignored.

Sheath-accumulating Propagation of Interplanetary Coronal Mass Ejection

NASA Astrophysics Data System (ADS)

Takahashi, Takuya; Shibata, Kazunari

2017-03-01

Fast interplanetary coronal mass ejections (ICMEs) are the drivers of strong space weather storms such as solar energetic particle events and geomagnetic storms. The connection between the space-weather-impacting solar wind disturbances associated with fast ICMEs at Earth and the characteristics of causative energetic CMEs observed near the Sun is a key question in the study of space weather storms, as well as in the development of practical space weather prediction. Such shock-driving fast ICMEs usually expand at supersonic speeds during the propagation, resulting in the continuous accumulation of shocked sheath plasma ahead. In this paper, we propose a “sheath-accumulating propagation” (SAP) model that describes the coevolution of the interplanetary sheath and decelerating ICME ejecta by taking into account the process of upstream solar wind plasma accumulation within the sheath region. Based on the SAP model, we discuss (1) ICME deceleration characteristics; (2) the fundamental condition for fast ICMEs at Earth; (3) the thickness of interplanetary sheaths; (4) arrival time prediction; and (5) the super-intense geomagnetic storms associated with huge solar flares. We quantitatively show that not only the speed but also the mass of the CME are crucial for discussing the above five points. The similarities and differences between the SAP model, the drag-based model, and the“snow-plow” model proposed by Tappin are also discussed.

Space Weather Studies Using Ground-based Experimental Complex in Kazakhstan

NASA Astrophysics Data System (ADS)

Kryakunova, O.; Yakovets, A.; Monstein, C.; Nikolayevskiy, N.; Zhumabayev, B.; Gordienko, G.; Andreyev, A.; Malimbayev, A.; Levin, Yu.; Salikhov, N.; Sokolova, O.; Tsepakina, I.

2015-12-01

Kazakhstan ground-based experimental complex for space weather study is situated near Almaty. Results of space environment monitoring are accessible via Internet on the web-site of the Institute of Ionosphere (http://www.ionos.kz/?q=en/node/21) in real time. There is a complex database with hourly data of cosmic ray intensity, geomagnetic field intensity, and solar radio flux at 10.7 cm and 27.8 cm wavelengths. Several studies using those data are reported. They are an estimation of speed of a coronal mass ejection, a study of large scale traveling distrubances, an analysis of geomagnetically induced currents using the geomagnetic field data, and a solar energetic proton event on 27 January 2012.

Concept Definition Study for In-Space Structural Characterization of a Lightweight Solar Array

NASA Technical Reports Server (NTRS)

Woods-Vedeler, Jessica A.; Pappa, Richard S.; Jones, Thomas W.; Spellman, Regina; Scott, Willis; Mockensturm, Eric M.; Liddle, Donn; Oshel, Ed; Snyder, Michael

2002-01-01

A Concept Definition Study (CDS) was conducted to develop a proposed "Lightweight High-Voltage Stretched-Lens Concentrator Solar Array Experiment" under NASA's New Millennium Program Space Technology-6 (NMP ST-6) activity. As part of a multi-organizational team, NASA Langley Research Center's role in this proposed experiment was to lead Structural Characterization of the solar array during the flight experiment. In support of this role, NASA LaRC participated in the CDS to de.ne an experiment for static, dynamic, and deployment characterization of the array. In this study, NASA LaRC traded state-of-the-art measurement approaches appropriate for an in-space, STS-based flight experiment, provided initial analysis and testing of the lightweight solar array and lens elements, performed a lighting and photogrammetric simulation in conjunction with JSC, and produced an experiment concept definition to meet structural characterization requirements.

Johnson Space Center's Solar and Wind-Based Renewable Energy System

NASA Technical Reports Server (NTRS)

Vasquez, A.; Ewert, M.; Rowlands, J.; Post, K.

2009-01-01

The NASA Johnson Space Center (JSC) in Houston, Texas has a Sustainability Partnership team that seeks ways for earth-based sustainability practices to also benefit space exploration research. A renewable energy gathering system was installed in 2007 at the JSC Child Care Center (CCC) which also offers a potential test bed for space exploration power generation and remote monitoring and control concepts. The system comprises: 1) several different types of photovoltaic panels (29 kW), 2) two wind-turbines (3.6 kW total), and 3) one roof-mounted solar thermal water heater and tank. A tie to the JSC local electrical grid was provided to accommodate excess power. The total first year electrical energy production was 53 megawatt-hours. A web-based real-time metering system collects and reports system performance and weather data. Improvements in areas of the CCC that were detected during subsequent energy analyses and some concepts for future efforts are also presented.

A space weather information service based upon remote and in-situ measurements of coronal mass ejections heading for Earth

NASA Astrophysics Data System (ADS)

Hartkorn, O. A.; Ritter, B.; Meskers, A. J. H.; Miles, O.; Russwurm, M.; Scully, S.; Roldan, A.; Juestel, P.; Reville, V.; Lupu, S.; Ruffenach, A.

2014-12-01

The Earth's magnetosphere is formed as a consequence of the interaction between the planet's magnetic field and the solar wind, a continuous plasma stream from the Sun. A number of different solar wind phenomena have been studied over the past forty years with the intention of understandingand forcasting solar behavior and space weather. In particular, Earth-bound interplanetary coronal mass ejections (CMEs) can significantly disturb the Earth's magnetosphere for a short time and cause geomagnetic storms. We present a mission concept consisting of six spacecraft that are equally spaced in a heliocentric orbit at 0.72 AU. These spacecraft will monitor the plasma properties, the magnetic field's orientation and magnitude, and the 3D-propagation trajectory of CMEs heading for Earth. The primary objective of this mission is to increase space weather forecasting time by means of a near real-time information service, that is based upon in-situ and remote measurements of the CME properties. The mission secondary objective is the improvement of scientific space weather models. In-situ measurements are performed using a Solar Wind Analyzer instrumentation package and flux gate magnetometers. For remote measurements, coronagraphs are employed. The proposed instruments originate from other space missions with the intention to reduce mission costs and to streamline the mission design process. Communication with the six identical spacecraft is realized via a deep space network consisting of six ground stations. This network provides an information service that is in uninterrupted contact with the spacecraft, allowing for continuos space weather monitoring. A dedicated data processing center will handle all the data, and forward the processed data to the SSA Space Weather Coordination Center. This organization will inform the general public through a space weather forecast. The data processing center will additionally archive the data for the scientific community. This concept mission allows for major advances in space weather forecasting and the scientific modeling of space weather.

The USGS geomagnetism program and its role in space weather monitoring

USGS Publications Warehouse

Love, Jeffrey J.; Finn, Carol A.

2011-01-01

Magnetic storms result from the dynamic interaction of the solar wind with the coupled magnetospheric-ionospheric system. Large storms represent a potential hazard for the activities and infrastructure of a modern, technologically based society [Baker et al., 2008]; they can cause the loss of radio communications, reduce the accuracy of global positioning systems, damage satellite electronics and affect satellite operations, increase pipeline corrosion, and induce voltage surges in electric power grids, causing blackouts. So while space weather starts with the Sun and is driven by the solar wind, it is on, or just above, the surface of the Earth that the practical effects of space weather are realized. Therefore, ground-based sensor networks, including magnetic observatories [Love, 2008], play an important role in space weather monitoring.

The USGS Geomagnetism Program and its role in Space-Weather Monitoring

USGS Publications Warehouse

Love, Jeffrey J.; Finn, Carol A.

2011-01-01

Magnetic storms result from the dynamic interaction of the solar wind with the coupled magnetospheric-ionospheric system. Large storms represent a potential hazard for the activities and infrastructure of a modern, technologically based society [Baker et al., 2008]; they can cause the loss of radio communications, reduce the accuracy of global positioning systems, damage satellite electronics and affect satellite operations, increase pipeline corrosion, and induce voltage surges in electric power grids, causing blackouts. So while space weather starts with the Sun and is driven by the solar wind, it is on, or just above, the surface of the Earth that the practical effects of space weather are realized. Therefore, ground-based sensor networks, including magnetic observatories [Love, 2008], play an important role in space weather monitoring.

Optical Amplifier Based Space Solar Power

NASA Technical Reports Server (NTRS)

Fork, Richard L.

2001-01-01

The objective was to design a safe optical power beaming system for use in space. Research was focused on identification of strategies and structures that would enable achievement near diffraction limited optical beam quality, highly efficient electrical to optical conversion, and high average power in combination in a single system. Efforts centered on producing high efficiency, low mass of the overall system, low operating temperature, precision pointing and tracking capability, compatibility with useful satellite orbits, component and system reliability, and long component and system life in space. A system based on increasing the power handled by each individual module to an optimum and the number of modules in the complete structure was planned. We were concerned with identifying the most economical and rapid path to commercially viable safe space solar power.

Solar-energy heats a transportation test center--Pueblo, Colorado

NASA Technical Reports Server (NTRS)

1981-01-01

Petroleum-base, thermal energy transport fluid circulating through 583 square feet of flat-plate solar collectors accumulates majority of energy for space heating and domestic hot-water of large Test Center. Report describes operation, maintenance, and performance of system which is suitable for warehouses and similar buildings. For test period from February 1979 to January 1980, solar-heating fraction was 31 percent, solar hot-water fraction 79 percent.

Solar Imaging UV/EUV Spectrometers Using TVLS Gratings

NASA Technical Reports Server (NTRS)

Thomas, Roger J.

2003-01-01

It is a particular challenge to develop a stigmatic spectrograph for UV, EUV wavelengths since the very low normal-incidence reflectance of standard materials most often requires that the design be restricted to a single optical element which must simultaneously provide both reimaging and spectral dispersion. This problem has been solved in the past by the use of toroidal gratings with uniform line-spaced rulings (TULS). A number of solar extreme ultraviolet (EUV) spectrometers have been based on such designs, including SOHO/CDS, Solar-B/EIS, and the sounding rockets Solar Extreme ultraviolet Research Telescope and Spectrograph (SERTS) and Extreme Ultraviolet Normal Incidence Spectrograph (EUNIS). More recently, Kita, Harada, and collaborators have developed the theory of spherical gratings with varied line-space rulings (SVLS) operated at unity magnification, which have been flown on several astronomical satellite missions. We now combine these ideas into a spectrometer concept that puts varied-line space rulings onto toroidal gratings. Such TVLS designs are found to provide excellent imaging even at very large spectrograph magnifications and beam-speeds, permitting extremely high-quality performance in remarkably compact instrument packages. Optical characteristics of three new solar spectrometers based on this concept are described: SUMI and RAISE, two sounding rocket payloads, and NEXUS, currently being proposed as a Small-Explorer (SMEX) mission.

Stretched Lens Array Photovoltaic Concentrator Technology Developed

NASA Technical Reports Server (NTRS)

Piszczor, Michael F., Jr.; O'Neill, Mark J.

2004-01-01

Solar arrays have been and continue to be the mainstay in providing power to nearly all commercial and government spacecraft. Light from the Sun is directly converted into electrical energy using solar cells. One way to reduce the cost of future space power systems is by minimizing the size and number of expensive solar cells by focusing the sunlight onto smaller cells using concentrator optics. The stretched lens array (SLA) is a unique concept that uses arched Fresnel lens concentrators to focus sunlight onto a line of high-efficiency solar cells located directly beneath. The SLA concept is based on the Solar Concentrator Array with Refractive Linear Element Technology (SCARLET) design that was used on NASA's New Millennium Deep Space 1 mission. The highly successful asteroid/comet rendezvous mission (1998 to 2001) demonstrated the performance and long-term durability of the SCARLET/SLA solar array design and set the foundation for further improvements to optimize its performance.

SPICE-Based Python Packages for ESA Solar System Exploration Mission's Geometry Exploitation

NASA Astrophysics Data System (ADS)

Costa, M.; Grass, M.

2018-04-01

This contribution outlines three Python packages to provide an enhanced and extended usage of SPICE Toolkit APIS providing higher-level functions and data quick-look capabilities focused on European Space Agency solar system exploration missions.

Use of low-energy hydrogen ion implants in high-efficiency crystalline-silicon solar cells

NASA Technical Reports Server (NTRS)

Fonash, S. J.; Sigh, R.; Mu, H. C.

1986-01-01

The use of low-energy hydrogen implants in the fabrication of high-efficiency crystalline silicon solar cells was investigated. Low-energy hydrogen implants result in hydrogen-caused effects in all three regions of a solar cell: emitter, space charge region, and base. In web, Czochralski (Cz), and floating zone (Fz) material, low-energy hydrogen implants reduced surface recombination velocity. In all three, the implants passivated the space charge region recombination centers. It was established that hydrogen implants can alter the diffusion properties of ion-implanted boron in silicon, but not ion-implated arsenic.

Technology requirements for GaAs photovoltaic arrays

NASA Technical Reports Server (NTRS)

Scott-Monck, J.; Rockey, D.

1981-01-01

An analysis based on percent GaAs solar cell weight and cost is performed to assess the utility of this cell for future space missions. It is shown that the GaAs substrate cost and the end-of-life (EOL) advantage the cell can provide over the space qualified silicon solar cell are the dominant factors determining potential use. Examples are presented to show that system level advantages resulting from reduction in solar panel area may warrant the use of GaAs at its current weight and projected initial cost provided the EOL advantage over silicon is at least 20 percent.

The Astronomy Spacelab Payloads Study: Executive volume

NASA Technical Reports Server (NTRS)

1975-01-01

The progress of the Astronomy Spacelab Payloads Project at the Goddard Space Flight Center is reported. Astronomical research in space, using the Spacelab in conjunction with the Space Shuttle, is described. The various fields of solar astronomy or solar physics, ultraviolet and optical astronomy, and high energy astrophysics are among the topics discussed. These fields include scientific studies of the sun and its dynamical processes, of the stars in wavelength regions not accessible to ground based observations, and the exciting new fields of X-ray, gamma ray, and particle astronomy.

SOLAR-ISS: A new reference spectrum based on SOLAR/SOLSPEC observations

NASA Astrophysics Data System (ADS)

Meftah, M.; Damé, L.; Bolsée, D.; Hauchecorne, A.; Pereira, N.; Sluse, D.; Cessateur, G.; Irbah, A.; Bureau, J.; Weber, M.; Bramstedt, K.; Hilbig, T.; Thiéblemont, R.; Marchand, M.; Lefèvre, F.; Sarkissian, A.; Bekki, S.

2018-03-01

Context. Since April 5, 2008 and up to February 15, 2017, the SOLar SPECtrometer (SOLSPEC) instrument of the SOLAR payload on board the International Space Station (ISS) has performed accurate measurements of solar spectral irradiance (SSI) from the middle ultraviolet to the infrared (165 to 3088 nm). These measurements are of primary importance for a better understanding of solar physics and the impact of solar variability on climate. In particular, a new reference solar spectrum (SOLAR-ISS) is established in April 2008 during the solar minima of cycles 23-24 thanks to revised engineering corrections, improved calibrations, and advanced procedures to account for thermal and aging corrections of the SOLAR/SOLSPEC instrument. Aims: The main objective of this article is to present a new high-resolution solar spectrum with a mean absolute uncertainty of 1.26% at 1σ from 165 to 3000 nm. This solar spectrum is based on solar observations of the SOLAR/SOLSPEC space-based instrument. Methods: The SOLAR/SOLSPEC instrument consists of three separate double monochromators that use concave holographic gratings to cover the middle ultraviolet (UV), visible (VIS), and infrared (IR) domains. Our best ultraviolet, visible, and infrared spectra are merged into a single absolute solar spectrum covering the 165-3000 nm domain. The resulting solar spectrum has a spectral resolution varying between 0.6 and 9.5 nm in the 165-3000 nm wavelength range. We build a new solar reference spectrum (SOLAR-ISS) by constraining existing high-resolution spectra to SOLAR/SOLSPEC observed spectrum. For that purpose, we account for the difference of resolution between the two spectra using the SOLAR/SOLSPEC instrumental slit functions. Results: Using SOLAR/SOLSPEC data, a new solar spectrum covering the 165-3000 nm wavelength range is built and is representative of the 2008 solar minimum. It has a resolution better than 0.1 nm below 1000 nm and 1 nm in the 1000-3000 nm wavelength range. The new solar spectrum (SOLAR-ISS) highlights significant differences with previous solar reference spectra and with solar spectra based on models. The integral of the SOLAR-ISS solar spectrum yields a total solar irradiance of 1372.3 ± 16.9 Wm-2 at 1σ, that is yet 11 Wm-2 over the value recommended by the International Astronomical Union in 2015. The spectrum shown in Fig. B.1 is available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/611/A1

Solar plasma geomagnetism and aurora

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chapman, S.

1968-01-01

This book is based on lectures given in July 1962 at the 12th session of the Les Houches Summer School of Theoretical Physics. Topics considered include geomagnetism and related phenomena, solar plasma in interplanetary space, mutual influence of the solar gas and the geomagnetic field. magnetic disturbance and aurorae, and the ring current and its DR field. (WDM)

Space Power Engineering Problems

NASA Astrophysics Data System (ADS)

Senkevich, V. P.

2002-01-01

Development of space power engineering in the first half of XXI century shall be aimed at preventing the forthcoming energy crisis and ecological catastrophes. The problem can be solved through using solar energy being perpetual, endless, and ecologically safe. As of now, issues on the development and employment of solar power stations and its beaming to the ground stations in the SHF band are put on the agenda. The most pressing problem is to develop orbital solar reflectors to illuminate towns in the polar regions, agricultural regions, and areas of processing sea products. Space-based technologies can be used to deal with typhoons, green house effects, and "ozone holes". Recently, large, frameless film structures formed by centrifugal forces offer the promise of structures for orbital power plants, reflectors, and solar sails. A big success is achieved in the development of power generating solar array elements of amorphous silicon. These innovations would make the development of orbital solar power plants dozens of times cheaper. Such solar arrays shall be used in the nearest future on heavy communication satellites and the Earth remote sensing platforms for generation of 140-160 kW at a specific power beyond 300 W/kg. The cargo traffic needed to develop and maintain the orbital power plants and reflector systems could be equipped with solar sails as the future low thrust propulsion. In 2000, the mankind witnessed an unexpected beginning of energy crisis along with strong hydro- meteorological events (typhoons, floods) that shocked the USA, the Western Europe, England, Japan, and other countries. The total damage is estimated as 90 billions of dollars. The mankind is approaching a boundary beyond which its further existence would depend on how people would learn to control weather and use ecologically safe power sources. Space technology base on the research potential accumulated in the previous century could serve for the solution of this problem.

Global Space Weather Observational Network: Challenges and China's Contribution

NASA Astrophysics Data System (ADS)

Wang, C.

2017-12-01

To understand space weather physical processes and predict space weather accurately, global space-borne and ground-based space weather observational network, making simultaneous observations from the Sun to geo-space (magnetosphere, ionosphere and atmosphere), plays an essential role. In this talk, we will present the advances of the Chinese space weather science missions, including the ASO-S (Advanced Space-borne Solar Observatory), MIT (Magnetosphere - Ionosphere- Thermosphere Coupling Exploration), and the ESA-China joint space weather science mission SMILE (Solar wind - Magnetosphere - Ionosphere Link Explore), a new mission to image the magnetosphere. Compared to satellites, ground-based monitors are cheap, convenient, and provide continuous real-time data. We will also introduce the Chinese Meridian Project (CMP), a ground-based program fully utilizing the geographic location of the Chinese landmass to monitor the geo-space environment. CMP is just one arm of a larger program that Chinese scientists are proposing to the international community. The International Meridian Circle Program (IMCP) for space weather hopes to connect chains of ground-based monitors at the longitudinal meridians 120 deg E and 60 deg W. IMCP takes advantage of the fact that these meridians already have the most monitors of any on Earth, with monitors in Russia, Australia, Brazil, the United States, Canada, and other countries. This data will greatly enhance the ability of scientists to monitor and predict the space weather worldwide.

Energy from space; Proceedings of the Symposium on Solar Energy from Space, Vienna, Austria, August 9-21, 1982

NASA Astrophysics Data System (ADS)

Freeman, J. W.

Aspects of solar power generation in space are considered. The subjects discussed include: a vision of future energy from space; solar power satellite concept for utilization of energy from space; the institutional challenge of solar power satellites; system study of the solar power satellite concept; market potential and possible limitations for satellite solar power stations; financing a solar power satellite project; and European questions related to satellite power systems. Also addressed are: options and high payoff choices for transportation; an electric propulsion transportation system from low-earth orbit to geostationary orbit utilizing beamed microwave power; the Canadarm robot arm of the Shuttle Remote Manipulator System; an early experimental solar power satellite; power economical considerations for the integration of terrestrial and extraterrestrial solar generators into existing power generation stations; and space solar power in perspective. For individual items see A84-21477 to A84-21489

Ion Acceleration in Solar Flares Determined by Solar Neutron Observations

NASA Astrophysics Data System (ADS)

Watanabe, K.; Solar Neutron Observation Group

2013-05-01

Large amounts of particles can be accelerated to relativistic energy in association with solar flares and/or accompanying phenomena (e.g., CME-driven shocks), and they sometimes reach very near the Earth and penetrate the Earth's atmosphere. These particles are observed by ground-based detectors (e.g., neutron monitors) as Ground Level Enhancements (GLEs). Some of the GLEs originate from high energy solar neutrons which are produced in association with solar flares. These neutrons are also observed by ground-based neutron monitors and solar neutron telescopes. Recently, some of the solar neutron detectors have also been operating in space. By observing these solar neutrons, we can obtain information about ion acceleration in solar flares. Such neutrons were observed in association with some X-class flares in solar cycle 23, and sometimes they were observed by two different types of detectors. For example, on 2005 September 7, large solar neutron signals were observed by the neutron monitor at Mt. Chacaltaya in Bolivia and Mexico City, and by the solar neutron telescopes at Chacaltaya and Mt. Sierra Negra in Mexico in association with an X17.0 flare. The neutron signal continued for more than 20 minutes with high statistical significance. Intense gamma-ray emission was also registered by INTEGRAL, and by RHESSI during the decay phase. We analyzed these data using the solar-flare magnetic-loop transport and interaction model of Hua et al. (2002), and found that the model could successfully fit the data with intermediate values of loop magnetic convergence and pitch angle scattering parameters. These results indicate that solar neutrons were produced at the same time as the gamma-ray line emission and that ions were continuously accelerated at the emission site. In this paper, we introduce some of the solar neutron observations in solar cycle 23, and discuss the tendencies of the physical parameters of solar neutron GLEs, and the energy spectrum and population of the accelerated particles produced in these solar flares, etc. We also report recent solar neutron observations by the Space Environment Data Acquisition equipment-Attached Payload (SEDA-AP) which has been installed on the international space station, and introduce the plan for the new solar neutron detector of the SciBar for the Cosmic Ray Telescope (SciCRT) at Mt. Sierra Negra in Mexico.

Solar power satellite system definition study, phase 2. Part 1: Midterm briefing

NASA Technical Reports Server (NTRS)

1979-01-01

An overview of the program plan for the Solar Power Satellite Program is given. Progress in the microwave power transmission system is reported. A description is given of the following: (1) launch and recovery site facilities, systems and operations; (2) cargo packaging; (3) earth-to-LEO cargo transportation operations; (4) LEO-to-GEO cargo transportation operations; (5) personnel transportation operations; (6) space vehicles in-space maintenance operations; and (7) SPS maintenance systems and operations. Other topics discussed include GEO base operations, satellite construction operations, intra-base logistics, and GEO base definition. A research and program plan is presented along with cost estimates.

Report of the solar physics panel

NASA Technical Reports Server (NTRS)

Withbroe, George L.; Fisher, Richard R.; Antiochos, Spiro; Brueckner, Guenter; Hoeksema, J. Todd; Hudson, Hugh; Moore, Ronald; Radick, Richard R.; Rottman, Gary; Scherrer, Philip

1991-01-01

Recent accomplishments in solar physics can be grouped by the three regions of the Sun: the solar interior, the surface, and the exterior. The future scientific problems and areas of interest involve: generation of magnetic activity cycle, energy storage and release, solar activity, solar wind and solar interaction. Finally, the report discusses a number of future space mission concepts including: High Energy Solar Physics Mission, Global Solar Mission, Space Exploration Initiative, Solar Probe Mission, Solar Variability Explorer, Janus, as well as solar physics on Space Station Freedom.

Space Radiation Research at NASA

NASA Technical Reports Server (NTRS)

Norbury, John

2016-01-01

The harmful effects of space radiation on astronauts is one of the most important limiting factors for human exploration of space beyond low Earth orbit, including a journey to Mars. This talk will present an overview of space radiation issues that arise throughout the solar system and will describe research efforts at NASA aimed at studying space radiation effects on astronauts, including the experimental program at the NASA Space Radiation Laboratory at Brookhaven National Laboratory. Recent work on galactic cosmic ray simulation at ground based accelerators will also be presented. The three major sources of space radiation, namely geomagnetically trapped particles, solar particle events and galactic cosmic rays will be discussed as well as recent discoveries of the harmful effects of space radiation on the human body. Some suggestions will also be given for developing a space radiation program in the Republic of Korea.

VERY LONG-PERIOD PULSATIONS BEFORE THE ONSET OF SOLAR FLARES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tan, Baolin; Huang, Jing; Tan, Chengming

Solar flares are the most powerful explosions occurring in the solar system, which may lead to disastrous space weather events and impact various aspects of our Earth. It remains a big challenge in modern astrophysics to understand the origin of solar flares and predict their onset. Based on the analysis of soft X-ray emission observed by the Geostationary Operational Environmental Satellite , this work reports a new discovery of very long-periodic pulsations occurring in the preflare phase before the onset of solar flares (preflare-VLPs). These pulsations typically have periods of 8–30 min and last for about 1–2 hr. They aremore » possibly generated from LRC oscillations of plasma loops where electric current dominates the physical process during magnetic energy accumulation in the source region. Preflare-VLPs provide essential information for understanding the triggering mechanism and origin of solar flares, and may be a convenient precursory indicator to help us respond to solar explosions and the corresponding disastrous space weather events.« less

Habitat Size Optimization of the O'Neill - Glaser Economic Model for Space Solar Satellite Production

NASA Technical Reports Server (NTRS)

Curreri, Peter A.; Detweiler, Michael

2010-01-01

Creating large space habitats by launching all materials from Earth is prohibitively expensive. Using space resources and space based labor to build space solar power satellites can yield extraordinary profits after a few decades. The economic viability of this program depends on the use of space resources and space labor. To maximize the return on the investment, the early use of high density bolo habitats is required. Other shapes do not allow for the small initial scale required for a quick population increase in space. This study found that 5 Man Year, or 384 person bolo high density habitats will be the most economically feasible for a program started at year 2010 and will cause a profit by year 24 of the program, put over 45,000 people into space, and create a large system of space infrastructure for the further exploration and development of space.

Interplanetary charged particle models (1974). [and the effects of cosmic exposure upon spacecraft and spacecraft components

NASA Technical Reports Server (NTRS)

Divine, N.

1975-01-01

The design of space vehicles for operation in interplanetary space is given, based on descriptions of solar wind, solar particle events, and galactic cosmic rays. A state-of-the-art review is presented and design criteria are developed from experiment findings aboard interplanetary and high-altitude earth-orbiting spacecraft. Solar cells were found to be particularly sensitive. Solar protons may also impact the reliability of electric propulsion systems and spacecraft surfaces, as well as causing interference, detector saturation, and spurious signals. Galactic cosmic-ray impact can lead to similar electronic failure and interference and may register in photographic films and other emulsions. It was concluded that solar wind electron measurements might result from differential charging when shadowed portions of the spacecraft acquired a negative charge from electron impact.

New Platforms for Suborbital Astronomical Observations and In Situ Atmospheric Measurements: Spacecraft, Instruments, and Facilities

NASA Astrophysics Data System (ADS)

Rodway, K.; DeForest, C. E.; Diller, J.; Vilas, F.; Sollitt, L. S.; Reyes, M. F.; Filo, A. S.; Anderson, E.

2014-12-01

Suborbital astronomical observations have over 50 years' history using NASA's sounding rockets and experimental space planes. The new commercial space industry is developing suborbital reusable launch vehicles (sRLV's) to provide low-cost, flexible, and frequent access to space at ~100 km altitude. In the case of XCOR Aerospace's Lynx spacecraft, the vehicle design and capabilities work well for hosting specially designed experiments that can be flown with a human-tended researcher or alone with the pilot on a customized mission. Some of the first-generation instruments and facilities that will conduct solar observations on dedicated Lynx science missions include the SwRI Solar Instrument Pointing Platform (SSIPP) and Atsa Suborbital Observatory, as well as KickSat sprites, which are picosatellites for in situ atmospheric and solar phenomena measurements. The SSIPP is a demonstration two-stage pointed solar observatory that operates inside the Lynx cockpit. The coarse pointing stage includes the pilot in the feedback loop, and the fine stage stabilizes the solar image to achieve arcsecond class pointing. SSIPP is a stepping-stone to future external instruments that can operate with larger apertures and shorter wavelengths in the solar atmosphere. The Planetary Science Institute's Atsa Suborbital Observatory combines the strengths of ground-based observatories and space-based observing to create a facility where a telescope is maintained and used interchangeably with either in-house facility instruments or user-provided instruments. The Atsa prototype is a proof of concept, hand-guided camera that mounts on the interior of the Lynx cockpit to test target acquisition and tracking for human-operated suborbital astronomy. KickSat sprites are mass-producible, one inch printed circuit boards (PCBs) populated by programmable off the shelf microprocessors and radios for real time data transmission. The sprite PCBs can integrate chip-based radiometers, magnetometers, accelerometers, etc. This low-cost, customizable platform provides researchers the ability to design immediately responsive, repeatable, high resolution experiments.

Solar Orbiter Status Update

NASA Astrophysics Data System (ADS)

Zouganelis, Y.; Mueller, D.; St Cyr, O. C.; Gilbert, H. R.

2016-12-01

Solar Orbiter, the first mission of ESA's Cosmic Vision 2015-2025 programme, promises to deliver groundbreaking science with previously unavailable observational capabilities provided by a suite of in-situ and remote-sensing instruments in a unique orbit. The mission will address the central question of heliophysics: How does the Sun create and control the heliosphere? The heliosphere represents a uniquely accessible domain of space, where fundamental physical processes common to solar, astrophysical and laboratory plasmas can be studied under conditions impossible to reproduce on Earth and unfeasible to observe from astronomical distances. In this talk, we highlight the scientific goals of Solar Orbiter, address the synergy between this joint ESA/NASA mission and other new space and ground-based observatories, and present the mission's development status.

Liquid Phase Deposition of Single-Phase Alpha-Copper-Indium-Diselenide

NASA Technical Reports Server (NTRS)

Hepp, Aloysius F.; Bailey, S.; Cowen, Jonathan; Lucas, L.; Ernst, Frank; Pirouz, P.

2004-01-01

The success of exploratory missions in outer space often depends on a highly efficient renewable energy supply, as provided by solar cells. Since future missions will demand large aggregates of solar cells, and space flight is expensive, the solar cells must furthermore be available at low costs and have a long lifetime and high resistance against structural damage introduced by irradiation with high energy electrons and protons. The photovoltaic materials that are presently available only partly fulfill all these requirements. Therefore, we propose to explore a new method for fabricating thin-films for cost-efficient solar cells with very high specific power,high irradiation resistance and long lifetime based on the alpha-phase of the Cu-In-Se system "alpha-CIS."

Space-based Solar Power: Possible Defense Applications and Opportunities for NRL Contributions

DTIC Science & Technology

2009-10-23

missions. At the spacecraft system level, a two-phase system can be used to transfer heat from a heat source (such as solar collectors and power...The solar arrays’ position allows them to radiate waste heat from both faces, as in conventional spacecraft practice. Both the antenna structure...Brayton cycle engine heated by a point-focus solar concentrator. NRL worked with NASA Glenn Research Center in developing means to integrate their

The Future of Operational Space Weather Observations

NASA Astrophysics Data System (ADS)

Berger, T. E.

2015-12-01

We review the current state of operational space weather observations, the requirements for new or evolved space weather forecasting capablities, and the relevant sections of the new National strategy for space weather developed by the Space Weather Operations, Research, and Mitigation (SWORM) Task Force chartered by the Office of Science and Technology Policy of the White House. Based on this foundation, we discuss future space missions such as the NOAA space weather mission to the L1 Lagrangian point planned for the 2021 time frame and its synergy with an L5 mission planned for the same period; the space weather capabilities of the upcoming GOES-R mission, as well as GOES-Next possiblities; and the upcoming COSMIC-2 mission for ionospheric observations. We also discuss the needs for ground-based operational networks to supply mission critical and/or backup space weather observations including the NSF GONG solar optical observing network, the USAF SEON solar radio observing network, the USGS real-time magnetometer network, the USCG CORS network of GPS receivers, and the possibility of operationalizing the world-wide network of neutron monitors for real-time alerts of ground-level radiation events.

Solar photoionization as a loss mechanism of neutral interstellar hydrogen in interplanetary space

NASA Technical Reports Server (NTRS)

Ogawa, H. S.; Wu, C. Y. Robert; Gangopadhyay, P.; Judge, D. L.

1995-01-01

Two primary loss mechanisms of interstellar neutral hydrogen in interplanetary space are resonance charge exchange ionization with solar wind protons and photoionization by solar EUV radiation. The later process has often been neglected since the average photoionization rate has been estimated to be as much as 5 to 10 times smaller than the charge exchange rate. These factors are based on ionization rates from early measurements of solar EUV and solar wind fluxes. Using revised solar EUV and solar wind fluxes measured near the ecliptic plane we have reinvestigated the ionization rates of interplanetary hydrogen. The result of our analysis indicates that indeed the photoionization rate during solar minimum can be smaller than charge exchange by a factor of 5; however, during solar maximum conditions when solar EUV fluxes are high, and solar wind fluxes are low, photoionization can be over 60% of the charge exchange rate at Earth orbit. To obtain an accurate estimate of the importance of photoionization relative to charge exchange, we have included photoionization from both the ground and metastable states of hydrogen. We find, however, that the photoionization from the metastable state does not contribute significantly to the overall photoionization rate.

Preparation of IHY-2007 in Indonesia: Local Observational Facilities, International Collaborations, and the Use of International Data

NASA Astrophysics Data System (ADS)

Djamaluddin, T.

2006-11-01

t_djamal@hotmail.com Since 1980, the National Institute of Aeronautics and Space (LAPAN) has been carrying out integrated observations of solar activities, geomagnetic disturbance, and ionospheric parameters, as well as other solar-terrestrial relationship research. International collaboration, especially with Japan in the field of solar physics, geomagnetism and equatorial atmosphere and with Australia in the field of ionosphere and upper atmosphere, help us in increasing national capacity building. The international data available on the Internet also helps us in comparing our local data with the global one or in fulfilling our needs of data due to lack of facilities, ground based or space based data. Some results will be reviewed. Preparation for IHY-2007 will also be discussed.

NASDA activities in space solar power system research, development and applications

NASA Technical Reports Server (NTRS)

Matsuda, Sumio; Yamamoto, Yasunari; Uesugi, Masato

1993-01-01

NASDA activities in solar cell research, development, and applications are described. First, current technologies for space solar cells such as Si, GaAs, and InP are reviewed. Second, future space solar cell technologies intended to be used on satellites of 21st century are discussed. Next, the flight data of solar cell monitor on ETS-V is shown. Finally, establishing the universal space solar cell calibration system is proposed.

Further Analyses of the NASA Glenn Research Center Solar Cell and Photovoltaic Materials Experiment Onboard the International Space Station

NASA Technical Reports Server (NTRS)

Myers, Matthew G.; Prokop, Norman F.; Krasowski, Michael J.; Piszczor, Michael F.; McNatt, Jeremiah S.

2016-01-01

Accurate air mass zero (AM0) measurement is essential for the evaluation of new photovoltaic (PV) technology for space solar cells. The NASA Glenn Research Center (GRC) has flown an experiment designed to measure the electrical performance of several solar cells onboard NASA Goddard Space Flight Center's (GSFC) Robotic Refueling Mission's (RRM) Task Board 4 (TB4) on the exterior of the International Space Station (ISS). Four industry and government partners provided advanced PV devices for measurement and orbital environment testing. The experiment was positioned on the exterior of the station for approximately eight months, and was completely self-contained, providing its own power and internal data storage. Several new cell technologies including four-junction (4J) Inverted Metamorphic Multi-Junction (IMM) cells were evaluated and the results will be compared to ground-based measurement methods.

Materials That Enhance Efficiency and Radiation Resistance of Solar Cells

NASA Technical Reports Server (NTRS)

Sun, Xiadong; Wang, Haorong

2012-01-01

A thin layer (approximately 10 microns) of a novel "transparent" fluorescent material is applied to existing solar cells or modules to effectively block and convert UV light, or other lower solar response waveband of solar radiation, to visible or IR light that can be more efficiently used by solar cells for additional photocurrent. Meanwhile, the layer of fluorescent coating material remains fully "transparent" to the visible and IR waveband of solar radiation, resulting in a net gain of solar cell efficiency. This innovation alters the effective solar spectral power distribution to which an existing cell gets exposed, and matches the maximum photovoltaic (PV) response of existing cells. By shifting a low PV response waveband (e.g., UV) of solar radiation to a high PV response waveband (e.g. Vis-Near IR) with novel fluorescent materials that are transparent to other solar-cell sensitive wavebands, electrical output from solar cells will be enhanced. This approach enhances the efficiency of solar cells by converting UV and high-energy particles in space that would otherwise be wasted to visible/IR light. This innovation is a generic technique that can be readily implemented to significantly increase efficiencies of both space and terrestrial solar cells, without incurring much cost, thus bringing a broad base of economical, social, and environmental benefits. The key to this approach is that the "fluorescent" material must be very efficient, and cannot block or attenuate the "desirable" and unconverted" waveband of solar radiation (e.g. Vis-NIR) from reaching the cells. Some nano-phosphors and novel organometallic complex materials have been identified that enhance the energy efficiency on some state-of-the-art commercial silicon and thin-film-based solar cells by over 6%.

Ground-Based High Energy Power Beaming in Support of Spacecraft Power Requirements

DTIC Science & Technology

2006-06-01

provide 900 W/m2. As more of the arriving energy is converted to space bus power and less goes into the production of heat , more solar cell output...similar control of peak power levels. Efficiency of power transfer may easily be about 50% as the solar cell experiences less heating effects as the...investigates the feasibility of projecting ground-based laser power to energize a spacecraft electrical bus via the solar panels. The energy is projected

Overview of NASA's Space Solar Power Technology Advanced Research and Development Program

NASA Technical Reports Server (NTRS)

Howell, Joe; Mankins, John C.; Davis, N. Jan (Technical Monitor)

2001-01-01

Large solar power satellite (SPS) systems that might provide base load power into terrestrial markets were examined extensively in the 1970s by the US Department of Energy (DOE) and the National Aeronautics and Space Administration (NASA). Following a hiatus of about 15 years, the subject of space solar power (SSP) was reexamined by NASA from 1995-1997 in the 'fresh look' study, and during 1998 in an SSP 'concept definition study', and during 1999-2000 in the SSP Exploratory Research and Technology (SERT) program. As a result of these efforts, during 2001, NASA has initiated the SSP Technology Advanced Research and Development (STAR-Dev) program based on informed decisions. The goal of the STAR-Dev program is to conduct preliminary strategic technology research and development to enable large, multi-megawatt to gigawatt-class space solar power (SSP) systems and wireless power transmission (WPT) for government missions and commercial markets (in-space and terrestrial). Specific objectives include: (1) Release a NASA Research Announcement (NRA) for SSP Projects; (2) Conduct systems studies; (3) Develop Component Technologies; (4) Develop Ground and Flight demonstration systems; and (5) Assess and/or Initiate Partnerships. Accomplishing these objectives will allow informed future decisions regarding further SSP and related research and development investments by both NASA management and prospective external partners. In particular, accomplishing these objectives will also guide further definition of SSP and related technology roadmaps including performance objectives, resources and schedules; including 'multi-purpose' applications (commercial, science, and other government).

Experimental Results from the Thermal Energy Storage-1 (TES-1) Flight Experiment

NASA Technical Reports Server (NTRS)

Wald, Lawrence W.; Tolbert, Carol; Jacqmin, David

1995-01-01

The Thermal Energy Storage-1 (TES-1) is a flight experiment that flew on the Space Shuttle Columbia (STS-62), in March 1994, as part of the OAST-2 mission. TES-1 is the first experiment in a four experiment suite designed to provide data for understanding the long duration microgravity behavior of thermal energy storage fluoride salts that undergo repeated melting and freezing. Such data have never been obtained before and have direct application for the development of space-based solar dynamic (SD) power systems. These power systems will store solar energy in a thermal energy salt such as lithium fluoride or calcium fluoride. The stored energy is extracted during the shade portion of the orbit. This enables the solar dynamic power system to provide constant electrical power over the entire orbit. Analytical computer codes have been developed for predicting performance of a spaced-based solar dynamic power system. Experimental verification of the analytical predictions is needed prior to using the analytical results for future space power design applications. The four TES flight experiments will be used to obtain the needed experimental data. This paper will focus on the flight results from the first experiment, TES-1, in comparison to the predicted results from the Thermal Energy Storage Simulation (TESSIM) analytical computer code. The TES-1 conceptual development, hardware design, final development, and system verification testing were accomplished at the NASA lewis Research Center (LeRC). TES-1 was developed under the In-Space Technology Experiment Program (IN-STEP), which sponsors NASA, industry, and university flight experiments designed to enable and enhance space flight technology. The IN-STEP Program is sponsored by the Office of Space Access and Technology (OSAT).

Solar Imaging UV/EUV Spectrometers Using TVLS Gratings

NASA Astrophysics Data System (ADS)

Thomas, R. J.

2003-05-01

It is a particular challenge to develop a stigmatic spectrograph for UV/EUV wavelengths since the very low normal-incidence reflectance of standard materials most often requires that the design be restricted to a single optical element which must simultaneously provide both re-imaging and spectral dispersion. This problem has been solved in the past by the use of toroidal gratings with uniform line-spaced rulings (TULS). A number of solar EUV spectrometers have been based on such designs, including SOHO/CDS, Solar-B/EIS, and the sounding rockets SERTS and EUNIS. More recently, Kita, Harada, and collaborators have developed the theory of spherical gratings with varied line-space rulings (SVLS) operated at unity magnification, which have been flown on several astronomical satellite missions. We now combine these ideas into a spectrometer concept that puts varied-line space rulings onto toroidal gratings. Such TVLS designs are found to provide excellent imaging even at very large spectrograph magnifications and beam-speeds, permitting extremely high-quality performance in remarkably compact instrument packages. Optical characteristics of three new solar spectrometers based on this concept are described: SUMI and RAISE, two sounding rocket payloads, and NEXUS, currently being proposed as a Small-Explorer (SMEX) mission.

Effect of the X5.4 Class Solar Flare Event of Solar Cycle 24 ON the GPS Signal Reception in Peninsular Malaysia

NASA Astrophysics Data System (ADS)

Ismail, S.; Musa, T. A.; Aris, W. A. W.; Gopir, G.

2016-09-01

In this paper, we examine the effect of solar flare event on the Global Positioning System (GPS) signal reception in Peninsular Malaysia during the X5.4 class solar flare on 7th March 2012, 00:24 UT at active region AR1429. GPS data from six MyRTKnet stations that cover the northern, southern, western and eastern regions of Peninsular Malaysia were used, namely Langkawi (Kedah), Bandar Baharu (Pulau Pinang), Pekan (Pahang), Mersing (Johor), Tanjung Pengelih (Johor) and Malacca (Malacca). The total electron content (TEC) was estimated based on the single layer ionospheric model. Next, the ionospheric delay for each GPS frequency of L1 (1575.42 MHz), L2 (1227.60 MHz) and L5 (1176.45 MHz) was then calculated. The results show that solar flare event can influence the GPS signal reception in Peninsular Malaysia where the X5.4 class solar flare shows significant effect of the ionospheric delay within the range of 9 m - 20 m. These research findings will significantly contribute to space weather study and its effects on space-based positioning system such as the GPS.

A Space-Based Near-Earth Object Survey Telescope in Support of Human Exploration, Solar System Science, and Planetary Defense

NASA Technical Reports Server (NTRS)

Abell, Paul A.

2011-01-01

Human exploration of near-Earth objects (NEOs) beginning in 2025 is one of the stated objectives of U.S. National Space Policy. Piloted missions to these bodies would further development of deep space mission systems and technologies, obtain better understanding of the origin and evolution of our Solar System, and support research for asteroid deflection and hazard mitigation strategies. As such, mission concepts have received much interest from the exploration, science, and planetary defense communities. One particular system that has been suggested by all three of these communities is a space-based NEO survey telescope. Such an asset is crucial for enabling affordable human missions to NEOs circa 2025 and learning about the primordial population of objects that could present a hazard to the Earth in the future.

Earth-Affecting Solar Causes Observatory (EASCO): A Potential International Living with a Star Mission from Sun-Earth L5

NASA Technical Reports Server (NTRS)

Gopalswamy, N.; Davila, J. M.; St Cyr, O. C.; Sittler, E. C.; Auchere, F.; Duvall, Jr. T. L.; Hoeksema, J. T.; Maksimovic, M.; MacDowall, R. J.; Szabo, A.;

Measuring the Electron Temperature in the Corona

NASA Technical Reports Server (NTRS)

Davila, Joseph; SaintCyr, Orville C.; Reginald, Nelson

2008-01-01

We report on an experiment to demonstrate the feasibility of a new method to obtain the electron temperature and flow speed in the solar corona by observing the visible Kcoronal spectrum during the total solar eclipse on 29 March 2006 in Libya. Results show that this new method is indeed feasible, giving electron temperatures and speeds of 1.10 $\\pm$ 0.05 MK, 103.0 $\\pm$ 92.0 $kmsA{-l}$; 0.98 $\\pm$ 0.12 MK, 0.0 + 10.0 $kmsA{-1)s; 0.70 $\\pm$ 0.08 MK, 0.0 + 10.0 $kmsA{-l)$ at l.l{\\it R)$ {\\odot}$ in the solar north, east and west, respectively, and 0.93 $\\pm$ 0.12 MK, 0.0 + 10.0 $kmsA{-l}$ at 1.2{\\it R}$ {\\odot}$ in the solar east. This new technique could be easily used from a space-based platform in a coronagraph to produce two dimensional maps of the electron temperature and bulk flow speed at the base of the solar wind useful for the study of heliospheric structure and space weather.

The Visibility of Earth Transits

NASA Technical Reports Server (NTRS)

Castellano, Timothy P.; Doyle, Laurance; McIntosh, Dawn; DeVincenzi, Donald (Technical Monitor)

2000-01-01

The recent photometric detection of planetary transits of the solar-like star HD 209458 at a distance of 47 parsecs suggest that transits can reveal the presence of Jupiter-size planetary companions in the solar neighborhood. Recent space-based transit searches have achieved photometric precision within an order of magnitude of that required to detect the much smaller transit signal of an earth-size planet across a solar-size star. Laboratory experiments in the presence of realistic noise sources have shown that CCDs can achieve photometric precision adequate to detect the 9.6 E-5 dimming of the Sun due to a transit of the Earth. Space-based solar irradiance monitoring has shown that the intrinsic variability of the Sun would not preclude such a detection. Transits of the Sun by the Earth would be detectable by observers that reside within a narrow band of sky positions near the ecliptic plane, if the observers possess current Earth epoch levels of technology and astronomical expertise. A catalog of solar-like stars that satisfy the geometric condition for Earth transit visibility are presented.

Space-Based Solar Power System Architecture

DTIC Science & Technology

2012-12-01

alternatives to fossil fuels: nuclear fission reactors, hydroelectric power, wind turbines and solar power to name just a few. Each has advantages...powered laser could give people or wildlife serious burns or cause blindness and possibly even death depending on exposure proximity and time. 11

Technology Projections for Solar Dynamic Power

NASA Technical Reports Server (NTRS)

Mason, Lee S.

1999-01-01

Solar Dynamic power systems can offer many potential benefits to Earth orbiting satellites including high solar-to-electric efficiency, long life without performance degradation, and high power capability. A recent integrated system test of a 2 kilowatt SD power system in a simulated space environment has successfully demonstrated technology readiness for space flight. Conceptual design studies of SD power systems have addressed several potential mission applications: a 10 kilowatt LEO satellite, a low power Space Based Radar, and a 30 kilowatt GEO communications satellite. The studies show that with moderate component development, SD systems can exhibit excellent mass and deployed area characteristics. Using the conceptual design studies as a basis, a SD technology roadmap was generated which identifies the component advances necessary to assure SD systems a competitive advantage for future NASA, DOD, and commercial missions.

Low-Frequency Radio Bursts and Space Weather

NASA Technical Reports Server (NTRS)

Gopalswamy, N.

2016-01-01

Low-frequency radio phenomena are due to the presence of nonthermal electrons in the interplanetary (IP) medium. Understanding these phenomena is important in characterizing the space environment near Earth and other destinations in the solar system. Substantial progress has been made in the past two decades, because of the continuous and uniform data sets available from space-based radio and white-light instrumentation. This paper highlights some recent results obtained on IP radio phenomena. In particular, the source of type IV radio bursts, the behavior of type III storms, shock propagation in the IP medium, and the solar-cycle variation of type II radio bursts are considered. All these phenomena are closely related to solar eruptions and active region evolution. The results presented were obtained by combining data from the Wind and SOHO missions.

Pegasus ICON Solar Array Illumination Test

NASA Image and Video Library

2018-05-04

A solar array illumination test is performed on NASA's Ionospheric Connection Explorer (ICON) in a clean room inside Building 1555 at Vandenberg Air Force Base in California on May 4, 2018. The test checks for any imperfections and confirms that the solar arrays are functioning properly. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on Orbital ATK's Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Pegasus ICON Solar Array Illumination Test

NASA Image and Video Library

2018-05-04

A solar array illumination test is performed on NASA's Ionospheric Connection Explorer (ICON) in a clean room on May 4, 2018, inside Building 1555 at Vandenberg Air Force Base in California. The test checks for any imperfections and confirms that the solar arrays are functioning properly. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on Orbital ATK's Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Pegasus ICON Solar Array Illumination Test

NASA Image and Video Library

2018-05-04

NASA's Ionospheric Connection Explorer (ICON) is prepared for a solar array illumination test in a clean room inside Building 1555 at Vandenberg Air Force Base in California on May 4, 2018. The test checks for any imperfections and confirms that the solar arrays are functioning properly. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on Orbital ATK's Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Pegasus ICON Solar Array Illumination Test

NASA Image and Video Library

2018-05-04

Technicians prepare NASA's Ionospheric Connection Explorer (ICON) for a solar array illumination test in a clean room inside Building 1555 at Vandenberg Air Force Base in California on May 4, 2018. The test checks for any imperfections and confirms that the solar arrays are functioning properly. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on Orbital ATK's Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

A new concept of space solar power satellite

NASA Astrophysics Data System (ADS)

Li, Xun; Duan, Baoyan; Song, Liwei; Yang, Yang; Zhang, Yiqun; Wang, Dongxu

2017-07-01

Space solar power satellite (SSPS) is a tremendous energy system that collects and converts solar power to electric power in space, and then transmits the electric power to earth wirelessly. In this paper, a novel SSPS concept based on ε-near-zero (ENZ) metamaterial is proposed. A spherical condenser made of ENZ metamaterial is developed, by using the refractive property of the ENZ metamaterial sunlight can be captured and redirected to its center. To make the geometric concentration ratio of the PV array reasonable, a hemispherical one located at the center is used to collect and convert the normal-incidence sunlight to DC power, then through a phased array transmitting antenna the DC power is beamed down to the rectenna on the ground. Detailed design of the proposed concept is presented.

Solar Sailing

NASA Technical Reports Server (NTRS)

Johnson, Les

2009-01-01

Solar sailing is a topic of growing technical and popular interest. Solar sail propulsion will make space exploration more affordable and offer access to destinations within (and beyond) the solar system that are currently beyond our technical reach. The lecture will describe solar sails, how they work, and what they will be used for in the exploration of space. It will include a discussion of current plans for solar sails and how advanced technology, such as nanotechnology, might enhance their performance. Much has been accomplished recently to make solar sail technology very close to becoming an engineering reality and it will soon be used by the world s space agencies in the exploration of the solar system and beyond. The first part of the lecture will summarize state-of-the-art space propulsion systems and technologies. Though these other technologies are the key to any deep space exploration by humans, robots, or both, solar-sail propulsion will make space exploration more affordable and offer access to distant and difficult destinations. The second part of the lecture will describe the fundamentals of space solar sail propulsion and will describe the near-, mid- and far-term missions that might use solar sails as a propulsion system. The third part of the lecture will describe solar sail technology and the construction of current and future sailcraft, including the work of both government and private space organizations.

GISS GCMAM Modeled Climate Responses to Total and Spectral Solar Forcing on Decadal and Centennial Time Scales

NASA Astrophysics Data System (ADS)

Wen, Guoyong; Cahalan, Robert; Rind, David; Jonas, Jeffrey; Pilewskie, Peter; Harder, Jerry

2014-05-01

We examine the influence of the SORCE (Solar Radiation and Climate Experiment) SIM (Spectral Irradiance Monitor) observed spectral solar irradiance (SSI) variations on Earth's climate. We apply two reconstructed spectral solar forcing scenarios, one SIM based, the other based on the SATIRE (Spectral And Total Irradiance REconstruction) model, as inputs to the GISS (Goddard Institute for Space Studies) GCMAM (Global Climate Middle Atmosphere Model) to examine the climate responses on decadal and centennial time scales. We show that the atmosphere has different temperature, ozone, and dynamic responses to the two solar spectral forcing scenarios, even when the variations in TSI (Total Solar Irradiance) are the same. We find that solar variations under either scenario contribute a small fraction of the observed temperature increase since the industrial revolution. The trend of global averaged surface air temperature response to the SIM-based solar forcing is 0.02 °C/century, about half of the temperature trend to the SATIRE-based SSI. However the temporal variation of the surface air temperature for the SIM-based solar forcing scenario is much larger compared to its SATIRE counterpart. Further research is required to examine TSI and SSI variations in the ascending phase of solar cycle 24, to assess their implications for the solar influence on climate.

GISS GCMAM Modeled Climate Responses to Total and Spectral Solar Forcing on Decadal and Centennial Time Scales

NASA Astrophysics Data System (ADS)

Wen, G.; Cahalan, R. F.; Rind, D. H.; Jonas, J.; Pilewskie, P.; Harder, J. W.; Krivova, N.

2014-12-01

We examine the influence of the SORCE (Solar Radiation and Climate Experiment) SIM (Spectral Irradiance Monitor) observed spectral solar irradiance (SSI) variations on Earth's climate. We apply two reconstructed spectral solar forcing scenarios, one SIM based, the other based on the SATIRE (Spectral And Total Irradiance REconstruction) model, as inputs to the GISS (Goddard Institute for Space Studies) GCMAM (Global Climate Middle Atmosphere Model) to examine the climate responses on decadal and centennial time scales. We show that the atmosphere has different temperature, ozone, and dynamic responses to the two solar spectral forcing scenarios, even when the variations in TSI (Total Solar Irradiance) are the same. We find that solar variations under either scenario contribute a small fraction of the observed temperature increase since the industrial revolution. The trend of global averaged surface air temperature response to the SIM-based solar forcing is 0.02 °C/century, about half of the temperature trend to the SATIRE-based SSI. However the temporal variation of the surface air temperature for the SIM-based solar forcing scenario is much larger compared to its SATIRE counterpart. Further research is required to examine TSI and SSI variations in the ascending phase of solar cycle 24, to assess their implications for the solar influence on climate.

LYRA, solar uv radiometer on the technology demonstration platform PROBA-2

NASA Astrophysics Data System (ADS)

Stockman, Y.; Hochedez, J.-F.; Schmutz, W.; BenMoussa, A.; Defise, J.-M.; Denis, F.; D'Olieslaeger, M.; Dominique, M.; Haenen, K.; Halain, J.-P.; Koller, S.; Koizumi, S.; Mortet, V.; Rochus, P.; Schühle, U.; Soltani, A.; Theissen, A.

2017-11-01

LYRA is a solar radiometer part of the PROBA 2 micro satellite payload. LYRA will monitor the solar irradiance in four soft X-Ray - VUV passbands. They have been chosen for their relevance to Solar Physics, Aeronomy and SpaceWeather: 1/ Lyman Alpha channel, 2/ Herzberg continuum range, 3/ Aluminium filter channel (including He II at 30.4 nm) and 4/ Zirconium filter channel. The radiometric calibration is traceable to synchrotron source standards. The stability will be monitored by on-board calibration sources (LEDs), which allow us to distinguish between potential degradations of the detectors and filters. Additionally, a redundancy strategy maximizes the accuracy and the stability of the measurements. LYRA will benefit from wide bandgap detectors based on diamond: it will be the first space assessment of revolutionary UV detectors. Diamond sensors make the instruments radiation-hard and solar-blind (insensitive to visible light) and therefore, make dispensable visible light blocking filters. To correlate the data of this new detector technology, well known technology, such as Si detectors are also embarked. The SWAP EUV imaging telescope will operate next to LYRA on PROBA-2. Together, they will provide a high performance solar monitor for operational space weather nowcasting and research. LYRA demonstrates technologies important for future missions such as the ESA Solar Orbiter.

The Coronal Solar Magnetism Observatory

NASA Astrophysics Data System (ADS)

Tomczyk, S.; Landi, E.; Zhang, J.; Lin, H.; DeLuca, E. E.

2015-12-01

Measurements of coronal and chromospheric magnetic fields are arguably the most important observables required for advances in our understanding of the processes responsible for coronal heating, coronal dynamics and the generation of space weather that affects communications, GPS systems, space flight, and power transmission. The Coronal Solar Magnetism Observatory (COSMO) is a proposed ground-based suite of instruments designed for routine study of coronal and chromospheric magnetic fields and their environment, and to understand the formation of coronal mass ejections (CME) and their relation to other forms of solar activity. This new facility will be operated by the High Altitude Observatory of the National Center for Atmospheric Research (HAO/NCAR) with partners at the University of Michigan, the University of Hawaii and George Mason University in support of the solar and heliospheric community. It will replace the current NCAR Mauna Loa Solar Observatory (http://mlso.hao.ucar.edu). COSMO will enhance the value of existing and new observatories on the ground and in space by providing unique and crucial observations of the global coronal and chromospheric magnetic field and its evolution. The design and current status of the COSMO will be reviewed.

SSI Variations in the visible as observed with SOLAR/SOLSPEC during cycle 24 - Comparison with SORCE/SIM.

NASA Astrophysics Data System (ADS)

Irbah, A.; Damé, L.; Meftah, M.; Bekki, S.; Bolsée, D.

2017-12-01

The solar spectral irradiance (SSI) and its temporal variations are of prime importance to apprehend the physics of the Sun and to understand its effects on Earth climate through changes of atmospheric properties. Ground based measurements of SSI are indeed affected by the Earth atmosphere and space observations are therefore required to perform adequate observations. Only a few long series of SSI space measurements were obtained these last decades. The SOLSPEC instrument of the SOLAR payload on the International Space Station (ISS) has recorded one of them from April 2008 to February 2017 covering almost the whole solar cycle 24. The instrument is a spectro-radiometer recording data of the Sun from 166 to 3088 nm. Operated from the ISS in a harsh environment it needed appropriate processing methods to extract significant scientific results from noise and instrumental effects. We present the methods used to process the data to evidence visible SSI variations during cycle 24. We discuss the results obtained showing SSI variations in phase with solar activity. We compare them with SORCE/SIM measurements.

Shuttle radiation dose measurements in the International Space Station orbits

NASA Technical Reports Server (NTRS)

Badhwar, Gautam D.

2002-01-01

The International Space Station (ISS) is now a reality with the start of a permanent human presence on board. Radiation presents a serious risk to the health and safety of the astronauts, and there is a clear requirement for estimating their exposures prior to and after flights. Predictions of the dose rate at times other than solar minimum or solar maximum have not been possible, because there has been no method to calculate the trapped-particle spectrum at intermediate times. Over the last few years, a tissue-equivalent proportional counter (TEPC) has been flown at a fixed mid-deck location on board the Space Shuttle in 51.65 degrees inclination flights. These flights have provided data that cover the expected changes in the dose rates due to changes in altitude and changes in solar activity from the solar minimum to the solar maximum of the current 23rd solar cycle. Based on these data, a simple function of the solar deceleration potential has been derived that can be used to predict the galactic cosmic radiation (GCR) dose rates to within +/-10%. For altitudes to be covered by the ISS, the dose rate due to the trapped particles is found to be a power-law function, rho(-2/3), of the atmospheric density, rho. This relationship can be used to predict trapped dose rates inside these spacecraft to +/-10% throughout the solar cycle. Thus, given the shielding distribution for a location inside the Space Shuttle or inside an ISS module, this approach can be used to predict the combined GCR + trapped dose rate to better than +/-15% for quiet solar conditions.

Near Earth Asteroid Scout: NASA's Solar Sail Mission to a NEA

NASA Technical Reports Server (NTRS)

Johnson, Les; Lockett, Tiffany

2017-01-01

NASA is developing a solar sail propulsion system for use on the Near Earth Asteroid (NEA) Scout reconnaissance mission and laying the groundwork for their use in future deep space science and exploration missions. Solar sails use sunlight to propel vehicles through space by reflecting solar photons from a large, mirror-like sail made of a lightweight, highly reflective material. This continuous photon pressure provides propellantless thrust, allowing for very high Delta V maneuvers on long-duration, deep space exploration. Since reflected light produces thrust, solar sails require no onboard propellant. The Near Earth Asteroid (NEA) Scout mission, funded by NASA's Advanced Exploration Systems Program and managed by NASA MSFC, will use the sail as primary propulsion allowing it to survey and image Asteroid 1991VG and, potentially, other NEA's of interest for possible future human exploration. NEA Scout uses a 6U cubesat (to be provided by NASA's Jet Propulsion Laboratory), an 86 m(exp. 2) solar sail and will weigh less than 12 kilograms. NEA Scout will be launched on the first flight of the Space Launch System in 2018. The solar sail for NEA Scout will be based on the technology developed and flown by the NASA NanoSail-D and The Planetary Society's Lightsail-A. Four approximately 7 m stainless steel booms wrapped on two spools (two overlapping booms per spool) will be motor deployed and pull the sail from its stowed volume. The sail material is an aluminized polyimide approximately 2.5 microns thick. As the technology matures, solar sails will increasingly be used to enable science and exploration missions that are currently impossible or prohibitively expensive using traditional chemical and electric propulsion systems. This paper will summarize the status of the NEA Scout mission and solar sail technology in general.

Optical design of visible emission line coronagraph on Indian space solar mission Aditya-L1

NASA Astrophysics Data System (ADS)

Raj Kumar, N.; Raghavendra Prasad, B.; Singh, Jagdev; Venkata, Suresh

2018-04-01

The ground based observations of the coronal emission lines using a coronagraph are affected by the short duration of clear sky and varying sky transparency. These conditions do not permit to study small amplitude variations in the coronal emission reliably necessary to investigate the process or processes involved in heating the coronal plasma and dynamics of solar corona. The proposed Visible Emission Line Coronagraph (VELC) over comes these limitations and will provide continuous observation 24 h a day needed for detailed studies of solar corona and drivers for space weather predictions. VELC payload onboard India's Aditya-L1 space mission is an internally occulted solar coronagraph for studying the temperature, velocity, density and heating of solar corona. To achieve the proposed science goals, an instrument which is capable of carrying out simultaneous imaging, spectroscopy and spectro-polarimetric observations of the solar corona close to the solar limb is required. VELC is designed with salient features of (a) Imaging solar corona at 500 nm with an angular resolution of 5 arcsec over a FOV of 1.05Ro to 3Ro (Ro:Solar radius) (b) Simultaneous multi-slit spectroscopy at 530.3 nm [Fe XIV],789.2 nm [Fe XI] and 1074.7 nm [Fe XIII] with spectral dispersion of 28mÅ, 31mÅ and 202mÅ per pixel respectively, over a FOV of 1.05Ro to 1.5Ro. (c) Multi-slit dual beam spectro-polarimetry at 1074.7 nm. All the components of instrument have been optimized in view of the scientific objectives and requirements of space payloads. In this paper we present the details of optical configuration and the expected performance of the payload.

Advanced Thin Film Solar Arrays for Space: The Terrestrial Legacy

NASA Technical Reports Server (NTRS)

Bailey, Sheila; Hepp, Aloysius; Raffaelle, Ryne; Flood, Dennis

2001-01-01

As in the case for single crystal solar cells, the first serious thin film solar cells were developed for space applications with the promise of better power to weight ratios and lower cost. Future science, military, and commercial space missions are incredibly diverse. Military and commercial missions encompass both hundreds of kilowatt arrays to tens of watt arrays 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. High power missions are particularly attractive for thin film utilization. These missions are generally those involving solar electric propulsion, surface power systems to sustain an outpost or a permanent colony on the surface of the Moon or Mars, space based lasers or radar, or large Earth orbiting power stations which can serve as central utilities for other orbiting spacecraft, or potentially beaming power to the Earth itself. This paper will discuss the current state of the art of thin film solar cells and the synergy with terrestrial thin film photovoltaic evolution. It will also address some of the technology development issues required to make thin film photovoltaics a viable choice for future space power systems.

Research and technology 1988

NASA Technical Reports Server (NTRS)

1988-01-01

This report presents the on-going research activities at the NASA Marshall Space Flight Center for the year 1988. The subjects presented are space transportation systems, shuttle cargo vehicle, materials processing in space, environmental data base management, microgravity science, astronomy, astrophysics, solar physics, magnetospheric physics, aeronomy, atomic physics, rocket propulsion, materials and processes, telerobotics, and space systems.

Re-Evaluating Satellite Solar Power Systems for Earth

NASA Technical Reports Server (NTRS)

Landis, Geoffrey A.

2006-01-01

The Solar Power Satellite System is a concept to collect solar power in space, and then transport it to the surface of the Earth by microwave (or possibly laser) beam, where if is converted into electrical power for terrestrial use. The recent increase in energy costs, predictions of the near-term exhaustion of oil, and prominence of possible climate change due to the "greenhouse effect" from burning of fossil fuels has again brought alternative energy sources to public attention, and the time is certainly appropriate to reexamine the economics of space based power. Several new concepts for Satellite Power System designs were evaluated to make the concept more economically feasible.

Cosmic Rays in the Heliosphere: Requirements for Future Observations

NASA Astrophysics Data System (ADS)

Mewaldt, R. A.

2013-06-01

Since the publication of Cosmic Rays in the Heliosphere in 1998 there has been great progress in understanding how and why cosmic rays vary in space and time. This paper discusses measurements that are needed to continue advances in relating cosmic ray variations to changes in solar and interplanetary activity and variations in the local interstellar environment. Cosmic ray acceleration and transport is an important discipline in space physics and astrophysics, but it also plays a critical role in defining the radiation environment for humans and hardware in space, and is critical to efforts to unravel the history of solar activity. Cosmic rays are measured directly by balloon-borne and space instruments, and indirectly by ground-based neutron, muon and neutrino detectors, and by measurements of cosmogenic isotopes in ice cores, tree-rings, sediments, and meteorites. The topics covered here include: what we can learn from the deep 2008-2009 solar minimum, when cosmic rays reached the highest intensities of the space era; the implications of 10Be and 14C isotope archives for past and future solar activity; the effects of variations in the size of the heliosphere; opportunities provided by the Voyagers for discovering the origin of anomalous cosmic rays and measuring cosmic-ray spectra in interstellar space; and future space missions that can continue the exciting exploration of the heliosphere that has occurred over the past 50 years.

MIC: Magnetically Deployable Structures for Power, Propulsion, Processing, Habitats and Energy Storage at Manned Lunar Bases

NASA Astrophysics Data System (ADS)

Powell, James; Maise, George; Paniagua, John; Rather, John

2007-01-01

MIC (Magnetically Inflated Cables) is a new approach for robotically erecting very large, strong, rigid, and ultra-lightweight structures in space. MIC structures use a network of high current (SC) cables with attached high tensile strength Kevlar or Spectra tethers. MIC is launched as a compact package of coiled SC cables and tethers on a conventional launch vehicle. Once in space the SC cables are electrically energized. The resultant strong outwards magnetic forces expand them and the restraining tethers into a large structure, which can be 100's of meters in size. MIC structures can be configured for many different applications, including solar electric generation, solar thermal propulsion, energy storage, large space telescopes, magnetic shielding for astronauts, etc. The MIC technology components, including high temperature superconductors (HTS), thermal insulation, high strength tethers, and cryogenic refrigerators all exist commercially. Refrigeration requirements are very modest, on the order of 100 watts thermal per kilometer of MIC cable, with an input electric power to the refrigeration system of ~5 kW(e) per km. baseline MIC designs are described for a manned lunar base, including: 1) a 1 MW(e) solar electric system, 2) a high Isp (~900 seconds) solar thermal tug to transport 30 ton payloads between the Earth and the Moon, 3) a 2000 Megajoule electric energy storage system for peaking and emergency power, and 4) a large (~1 km) space telescope.

Sheath-accumulating Propagation of Interplanetary Coronal Mass Ejection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Takahashi, Takuya; Shibata, Kazunari, E-mail: takahasi@kusastro.kyoto-u.ac.jp

Fast interplanetary coronal mass ejections (ICMEs) are the drivers of strong space weather storms such as solar energetic particle events and geomagnetic storms. The connection between the space-weather-impacting solar wind disturbances associated with fast ICMEs at Earth and the characteristics of causative energetic CMEs observed near the Sun is a key question in the study of space weather storms, as well as in the development of practical space weather prediction. Such shock-driving fast ICMEs usually expand at supersonic speeds during the propagation, resulting in the continuous accumulation of shocked sheath plasma ahead. In this paper, we propose a “sheath-accumulating propagation”more » (SAP) model that describes the coevolution of the interplanetary sheath and decelerating ICME ejecta by taking into account the process of upstream solar wind plasma accumulation within the sheath region. Based on the SAP model, we discuss (1) ICME deceleration characteristics; (2) the fundamental condition for fast ICMEs at Earth; (3) the thickness of interplanetary sheaths; (4) arrival time prediction; and (5) the super-intense geomagnetic storms associated with huge solar flares. We quantitatively show that not only the speed but also the mass of the CME are crucial for discussing the above five points. The similarities and differences between the SAP model, the drag-based model, and the“snow-plow” model proposed by Tappin are also discussed.« less

High resolution solar observations in the context of space weather prediction

NASA Astrophysics Data System (ADS)

Yang, Guo

Space weather has a great impact on the Earth and human life. It is important to study and monitor active regions on the solar surface and ultimately to predict space weather based on the Sun's activity. In this study, a system that uses the full power of speckle masking imaging by parallel processing to obtain high-spatial resolution images of the solar surface in near real-time has been developed and built. The application of this system greatly improves the ability to monitor the evolution of solar active regions and to predict the adverse effects of space weather. The data obtained by this system have also been used to study fine structures on the solar surface and their effects on the upper solar atmosphere. A solar active region has been studied using high resolution data obtained by speckle masking imaging. Evolution of a pore in an active region presented. Formation of a rudimentary penumbra is studied. The effects of the change of the magnetic fields on the upper level atmosphere is discussed. Coronal Mass Ejections (CMEs) have a great impact on space weather. To study the relationship between CMEs and filament disappearance, a list of 431 filament and prominence disappearance events has been compiled. Comparison of this list with CME data obtained by satellite has shown that most filament disappearances seem to have no corresponding CME events. Even for the limb events, only thirty percent of filament disappearances are associated with CMEs. A CME event that was observed on March 20, 2000 has been studied in detail. This event did not show the three-parts structure of typical CMEs. The kinematical and morphological properties of this event were examined.

Solar power satellite system definition study, volume 4, phase 2

NASA Technical Reports Server (NTRS)

1979-01-01

Results of an overall evaluation of the solar power satellite concept are reported. Specific topics covered include: solid state sandwich configuration; parametric development of reliability design; power distribution system for solid state solar power satellites; multibeam transmission; GEO base system configuration; suppression of the heavy lift launch vehicle trajectory; conceptual design of an offshore space center facility; solar power satellite development and operations scenario; and microwave power transmission technology, advancement, development, and facility requirements.

Utilizing Fission Technology to Enable Rapid and Affordable Access to any Point in the Solar System

NASA Technical Reports Server (NTRS)

Houts, Mike; Bonometti, Joe; Morton, Jeff; Hrbud, Ivana; Bitteker, Leo; VanDyke, Melissa; Godfroy, T.; Pedersen, K.; Dobson, C.; Patton, B.;

Transmission Electron Microscopy of Plagioclase-Rich Itokawa Grains: Space Weathering Effects and Solar Flare Track Exposure Ages

NASA Technical Reports Server (NTRS)

Keller, Lindsay P.; Berger, Eve L.

2017-01-01

Limited samples are available for the study of space weathering effects on airless bodies. The grains returned by the Hayabusa mission to asteroid 25143 Itokawa provide the only samples currently available to study space weathering of ordinary chondrite regolith. We have previously studied olivine-rich Itokawa grains and documented their surface alteration and exposure ages based on the observed density of solar flare particle tracks. Here we focus on the rarer Itokawa plagioclase grains, in order to allow comparisons between Itokawa and lunar soil plagioclase grains for which an extensive data set exists.

Variation of TEC and related parameters over the Indian EIA region from ground and space based GPS observations during the low solar activity period of May 2007-April 2008

NASA Astrophysics Data System (ADS)

Chakravarty, S. C.; Nagaraja, Kamsali; Jakowski, N.

2017-03-01

The annual variations of ionospheric Total Electron Content (TEC), F-region peak ionisation (NmF2) and the ionospheric slab thickness (τ) over the Indian region during the low solar activity period of May 2007-April 2008 have been studied. For this purpose the ground based TEC data obtained from GAGAN measurements and the space based data from GPS radio occultation technique using CHAMP have been utilised. The results of these independent measurements are combined to derive additional parameters such as the equivalent slab thickness of the total and the bottom-side ionospheric regions (τT and τB). The one year hourly average values of all these parameters over the ionospheric anomaly latitude region (10-26°N) are presented here along with the statistical error estimates. It is expected that these results are potentially suited to be used as base level values during geomagnetically quiet and undisturbed solar conditions.

Science at the Goddard Space Flight Center

NASA Technical Reports Server (NTRS)

White, Nicholas E.

2012-01-01

The Sciences and Exploration Directorate of the NASA Goddard Space Flight Center (GSFC) is the largest Earth and space science research organization in the world. Its scientists advance understanding of the Earth and its life-sustaining environment, the Sun, the solar system, and the wider universe beyond. Researchers in the Sciences and Exploration Directorate work with engineers, computer programmers, technologists, and other team members to develop the cutting-edge technology needed for space-based research. Instruments are also deployed on aircraft, balloons, and Earth's surface. I will give an overview of the current research activities and programs at GSFC including the James Web Space Telescope (JWST), future Earth Observing programs, experiments that are exploring our solar system and studying the interaction of the Sun with the Earth's magnetosphere.

Age Induced Effects on ESD Characteristics of Solar Array Coupons After Combined Space Environmental Exposures

NASA Technical Reports Server (NTRS)

Wright, Kenneth H.; Schneider, Todd A.; Vaughn, Jason A.; Hoang, Bao; Funderburk, Victor V.; Wong, Frankie; Gardiner, George

2012-01-01

A set of multi-junction GaAs/Ge solar array test coupons provided by Space Systems/Loral were subjected to a sequence of 5-year increments of combined space environment exposure tests. The test coupons capture an integrated design intended for use in a geosynchronous (GEO) space environment. A key component of this test campaign is performing electrostatic discharge (ESD) tests in the inverted gradient mode. The protocol of the ESD tests is based on the ISO standard for ESD testing on solar array panels [ISO-11221]. The test schematic in the ISO reference has been modified with Space System/Loral designed circuitry to better simulate the on-orbit operational conditions of its solar array design. Part of the modified circuitry is to simulate a solar array panel coverglass flashover discharge. All solar array coupons used in the test campaign consist of four cells constructed to form two strings. The ESD tests were performed at the beginning-of-life (BOL) and at each 5-year environment exposure point until end-of-life (EOL) at 15 years. The space environmental exposure sequence consisted of ultra-violet radiation, electron/proton particle radiation, thermal cycling, and Xenon ion thruster plume erosion. This paper describes the ESD test setup and the importance of the electrical test design in simulating the on-orbit operational conditions. Arc inception voltage results along with ESD test behavior from the BOL condition through the 15th year age condition are discussed. In addition, results from a Xenon plasma plume exposure test with an EOL coupon under the full ESD test condition will be discussed.

The Importance of Reconnection at Sector Boundaries: Another Space Weather Hazard?

NASA Astrophysics Data System (ADS)

Qi, Y.; Lai, H.; Russell, C. T.

2017-12-01

Sector Boundaries are interfaces between nearly oppositely directed magnetic flux in the solar wind. When the leading solar wind stream is moving more slowly than the following stream a high-pressure ridge appears at the interface, that compresses the plasma sometimes leading to a forward and reverse shock pair that slows the fast stream and accelerate the slow stream. If reconnection at the interface between the streams occurs part of the magnetic flux will be annihilated but the plasma once associated with that magnetic flux remains near the interface causing a sometimes significant short-lived dynamic pressure increase. The declining phase of solar cycle 24 exhibits several examples of the phenomenon with densities reaching over 80 protons cm-3 at speed of about 400 km sec-1. We examine the solar wind context of the phenomenon and the consequences at the magnetosphere using space-based and ground-based observations and comment on their possible generation of geomagnetically-induced currents.

Overview of Space Station attached payloads in the areas of solar physics, solar terrestrial physics, and plasma processes

NASA Technical Reports Server (NTRS)

Roberts, W. T.; Kropp, J.; Taylor, W. W. L.

1986-01-01

This paper outlines the currently planned utilization of the Space Station to perform investigations in solar physics, solar terrestrial physics, and plasma physics. The investigations and instrumentation planned for the Solar Terrestrial Observatory (STO) and its associated Space Station accommodation requirements are discussed as well as the planned placement of the STO instruments and typical operational scenarios. In the area of plasma physics, some preliminary plans for scientific investigations and for the accommodation of a plasma physics facility attached to the Space Station are outlined. These preliminary experiment concepts use the space environment around the Space Station as an unconfined plasma laboratory. In solar physics, the initial instrument complement and associated accommodation requirements of the Advanced Solar Observatory are described. The planned evolutionary development of this observatory is outlined, making use of the Space Station capabilities for servicing and instrument reconfiguration.

Early commercial demonstration of space solar power using ultra-lightweight arrays

NASA Astrophysics Data System (ADS)

Reed, Kevin; Willenberg, Harvey J.

2009-11-01

Space solar power shows great promise for future energy sources worldwide. Most central power stations operate with power capacity of 1000 MW or greater. Due to launch size limitations and specific power of current, rigid solar arrays, the largest solar arrays that have flown in space are around 50 kW. Thin-film arrays offer the promise of much higher specific power and deployment of array sizes up to several MW with current launch vehicles. An approach to early commercial applications for space solar power to distribute power to charge hand-held, mobile battery systems by wireless power transmission (WPT) from thin-film solar arrays in quasi-stationary orbits will be presented. Four key elements to this prototype will be discussed: (1) Space and near-space testing of prototype wireless power transmission by laser and microwave components including WPT space to space and WPT space to near-space HAA transmission demonstrations; (2) distributed power source for recharging hand-held batteries by wireless power transmission from MW space solar power systems; (3) use of quasi-geostationary satellites to generate electricity and distribute it to targeted areas; and (4) architecture and technology for ultra-lightweight thin-film solar arrays with specific energy exceeding 1 kW/kg. This approach would yield flight demonstration of space solar power and wireless power transmission of 1.2 MW. This prototype system will be described, and a roadmap will be presented that will lead to still higher power levels.

Transitioning the Rice Realtime Forecast Models to DSCOVR

NASA Astrophysics Data System (ADS)

Bala, R.; Reiff, P. H.

2016-12-01

The Rice realtime forecast models of global magnetospheric indices Kp, Dst and AE have been actively running at mms.rice.edu/realtime/forecast.html for nearly a decade now. These neural network models were trained using the ACE archival solar wind data while the near-realtime forecasts are provided using instantaneous upwind solar wind data stream measured at the L1 point through ACE. Additionally, the webpage also provide status of the current space weather condition as an additional resource, updating every ten minutes. Furthermore, the subscribers of our space weather alert system, called `spacalrt', have been receiving email notices based on predefined thresholds. One of the gaps that is currently seen in the Rice neural network models lies in the density dependent models using variants of the solar wind pressure. The anomalous behavior in reporting densities in ACE has been a common issue for some time now. Often such behavior is observed when the solar energetic particle that are associated with solar flares or CMEs are Earth directed. Therefore, it is understood that the subsequent measures of the density reported by ACE will be either very low or, at a minimum, contaminated. Under these circumstances, the density-based Rice models typically underpredict. However, the newly launched DSCOVR satellite will help enhance our prediction models with high-quality data; it has real time space weather data available through the NOAA's Space Weather Prediction Center as of July, 2016. We are in the process of transitioning our forecast operations to include data from DSCOVR while running the original ACE data stream in parallel until it lasts. This paper will compare and contrast the forecasted values from the two satellites. Finally, we will discuss our efforts in providing the forecast products for the Rice space weather website that will be a part of the book on "Machine Learning Techniques for Space Weather" to be published by Elsiever.

Modeling, Simulation, and Control of a Solar Electric Propulsion Vehicle in Near-Earth Vicinity Including Solar Array Degradation

NASA Technical Reports Server (NTRS)

Witzberger, Kevin (Inventor); Hojnicki, Jeffery (Inventor); Manzella, David (Inventor)

2016-01-01

Modeling and control software that integrates the complexities of solar array models, a space environment, and an electric propulsion system into a rigid body vehicle simulation and control model is provided. A rigid body vehicle simulation of a solar electric propulsion (SEP) vehicle may be created using at least one solar array model, at least one model of a space environment, and at least one model of a SEP propulsion system. Power availability and thrust profiles may be determined based on the rigid body vehicle simulation as the SEP vehicle transitions from a low Earth orbit (LEO) to a higher orbit or trajectory. The power availability and thrust profiles may be displayed such that a user can use the displayed power availability and thrust profiles to determine design parameters for an SEP vehicle mission.

Microphysics of Waves and Instabilities in the Solar Wind and their Macro Manifestations in the Corona and Interplanetary Space

NASA Technical Reports Server (NTRS)

Gurman, Joseph (Technical Monitor); Habbal, Shadia Rifai

2004-01-01

Investigations of the physical processes responsible for coronal heating and the acceleration of the solar wind were pursued with the use of our recently developed 2D MHD solar wind code and our 1D multifluid code. In particular, we explored (1) the role of proton temperature anisotropy in the expansion of the solar wind, (2) the role of plasma parameters at the coronal base in the formation of high speed solar wind streams at mid-latitudes, and (3) the heating of coronal loops.

A propagation tool to connect remote-sensing observations with in-situ measurements of heliospheric structures

NASA Astrophysics Data System (ADS)

Rouillard, A. P.; Lavraud, B.; Génot, V.; Bouchemit, M.; Dufourg, N.; Plotnikov, I.; Pinto, R. F.; Sanchez-Diaz, E.; Lavarra, M.; Penou, M.; Jacquey, C.; André, N.; Caussarieu, S.; Toniutti, J.-P.; Popescu, D.; Buchlin, E.; Caminade, S.; Alingery, P.; Davies, J. A.; Odstrcil, D.; Mays, L.

2017-11-01

The remoteness of the Sun and the harsh conditions prevailing in the solar corona have so far limited the observational data used in the study of solar physics to remote-sensing observations taken either from the ground or from space. In contrast, the 'solar wind laboratory' is directly measured in situ by a fleet of spacecraft measuring the properties of the plasma and magnetic fields at specific points in space. Since 2007, the solar-terrestrial relations observatory (STEREO) has been providing images of the solar wind that flows between the solar corona and spacecraft making in-situ measurements. This has allowed scientists to directly connect processes imaged near the Sun with the subsequent effects measured in the solar wind. This new capability prompted the development of a series of tools and techniques to track heliospheric structures through space. This article presents one of these tools, a web-based interface called the 'Propagation Tool' that offers an integrated research environment to study the evolution of coronal and solar wind structures, such as Coronal Mass Ejections (CMEs), Corotating Interaction Regions (CIRs) and Solar Energetic Particles (SEPs). These structures can be propagated from the Sun outwards to or alternatively inwards from planets and spacecraft situated in the inner and outer heliosphere. In this paper, we present the global architecture of the tool, discuss some of the assumptions made to simulate the evolution of the structures and show how the tool connects to different databases.

Multiple Views

NASA Image and Video Library

2017-12-08

This CME image from Oct. 7, 2012, captured by two instruments on STEREO, shows the eruption from its base out into space. The base of the CME near the sun is seen in extreme ultraviolet light emitted directly from the solar material; the growing loop is seen in visible light. Credit: NASA/STEREO CME WEEK: What To See in CME Images Two main types of explosions occur on the sun: solar flares and coronal mass ejections. Unlike the energy and x-rays produced in a solar flare – which can reach Earth at the speed of light in eight minutes – coronal mass ejections are giant, expanding clouds of solar material that take one to three days to reach Earth. Once at Earth, these ejections, also called CMEs, can impact satellites in space or interfere with radio communications. During CME WEEK from Sept. 22 to 26, 2014, we explore different aspects of these giant eruptions that surge out from the star we live with. When a coronal mass ejection blasts off the sun, scientists rely on instruments called coronagraphs to track their progress. Coronagraphs block out the bright light of the sun, so that the much fainter material in the solar atmosphere -- including CMEs -- can be seen in the surrounding space. CMEs appear in these images as expanding shells of material from the sun's atmosphere -- sometimes a core of colder, solar material (called a filament) from near the sun's surface moves in the center. But mapping out such three-dimensional components from a two-dimensional image isn't easy. Watch the slideshow to find out how scientists interpret what they see in CME pictures. The images in the slideshow are from the three sets of coronagraphs NASA currently has in space. One is on the joint European Space Agency and NASA Solar and Heliospheric Observatory, or SOHO. SOHO launched in 1995, and sits between Earth and the sun about a million miles away from Earth. The other two coronagraphs are on the two spacecraft of the NASA Solar Terrestrial Relations Observatory, or STEREO, mission, which launched in 2006. The two STEREO spacecraft are both currently viewing the far side of the sun. Together these instruments help scientists create a three-dimensional model of any CME as its journey unfolds through interplanetary space. Such information can show why a given characteristic of a CME close to the sun might lead to a given effect near Earth, or any other planet in the solar system...NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Lightweight Solar Photovoltaic Blankets

NASA Technical Reports Server (NTRS)

Ceragioli, R.; Himmler, R.; Nath, P.; Vogeli, C.; Guha, S.

1995-01-01

Lightweight, flexible sheets containing arrays of stacked solar photovoltaic cells developed to supply electric power aboard spacecraft. Solar batteries satisfying stringent requirements for operation in outer space also adaptable to terrestrial environment. Attractive for use as long-lived, portable photovoltaic power sources. Cells based on amorphous silicon which offers potential for order-of-magnitude increases in power per unit weight, power per unit volume, and endurance in presence of ionizing radiation.

Low Earth orbit atomic oxygen simulation for durability evaluation of solar reflector surfaces

NASA Technical Reports Server (NTRS)

Degroh, Kim K.; Banks, Bruce A.

1992-01-01

To evaluate the performance and durability of solar reflector surfaces in the atomic oxygen environment typical of low Earth orbit (LEO), one must expose the reflector surface either directly to LEO or to ground-laboratory atomic oxygen environments. Although actual LEO exposures are most desired, such opportunities are typically scarce, expensive, and of limited duration. As a result, ground-laboratory exposures must be relied upon as the most practical long-term durability evaluation technique. Plasma ashers are widely used as LEO simulation facilities by producing atomic oxygen environments for durability evaluation of potential spacecraft materials. Atomic oxygen arrival differs between ground and space exposure in that plasma asher exposure produces isotropic arrival and space solar tracking produces sweeping arrival. Differences in initial impact reaction probability occur, dependent upon the energy and species existing in these environments. Due to the variations in ground-laboratory and space atomic oxygen, quantification of in-space performance based on plasma asher testing is not straightforward. The various atomic oxygen interactions that can occur with reflector surfaces, such as undercutting in organic substrates at protective coating defect sites, ground-laboratory techniques recommended for evaluating the atomic oxygen durability of reflectors based on asher exposures, and computational techniques which make use of ground-laboratory atomic oxygen exposure to predict in-space LEO durability are addressed.

Department of Defense Spacelift in a Fiscally Constrained Environment

DTIC Science & Technology

2011-12-16

or space operations. Space weather may impact spacecraft and ground-based systems. Space weather is influenced by phenomena such as solar flare...shareholders included Rocket and Science Corporation Energia (Russian- based company), a Norwegian shipbuilder, and two Ukrainian rocket firms (Hennigan...Hennigan 2011b). In October 2010, Sea Launch AG emerged from Chapter 11 bankruptcy protection as a result of Rocket and Science Corporation Energia

Heliophysics at total solar eclipses

NASA Astrophysics Data System (ADS)

Pasachoff, Jay M.

2017-08-01

Observations during total solar eclipses have revealed many secrets about the solar corona, from its discovery in the 17th century to the measurement of its million-kelvin temperature in the 19th and 20th centuries, to details about its dynamics and its role in the solar-activity cycle in the 21st century. Today's heliophysicists benefit from continued instrumental and theoretical advances, but a solar eclipse still provides a unique occasion to study coronal science. In fact, the region of the corona best observed from the ground at total solar eclipses is not available for view from any space coronagraphs. In addition, eclipse views boast of much higher quality than those obtained with ground-based coronagraphs. On 21 August 2017, the first total solar eclipse visible solely from what is now United States territory since long before George Washington's presidency will occur. This event, which will cross coast-to-coast for the first time in 99 years, will provide an opportunity not only for massive expeditions with state-of-the-art ground-based equipment, but also for observations from aloft in aeroplanes and balloons. This set of eclipse observations will again complement space observations, this time near the minimum of the solar activity cycle. This review explores the past decade of solar eclipse studies, including advances in our understanding of the corona and its coronal mass ejections as well as terrestrial effects. We also discuss some additional bonus effects of eclipse observations, such as recreating the original verification of the general theory of relativity.

Space-based solar power conversion and delivery systems study. Volume 5: Economic analysis

NASA Technical Reports Server (NTRS)

1977-01-01

Space-based solar power conversion and delivery systems are studied along with a variety of economic and programmatic issues relevant to their development and deployment. The costs, uncertainties and risks associated with the current photovoltaic Satellite Solar Power System (SSPS) configuration, and issues affecting the development of an economically viable SSPS development program are addressed. In particular, the desirability of low earth orbit (LEO) and geosynchronous (GEO) test satellites is examined and critical technology areas are identified. The development of SSPS unit production (nth item), and operation and maintenance cost models suitable for incorporation into a risk assessment (Monte Carlo) model (RAM) are reported. The RAM was then used to evaluate the current SSPS configuration expected costs and cost-risk associated with this configuration. By examining differential costs and cost-risk as a function of postulated technology developments, the critical technologies, that is, those which drive costs and/or cost-risk, are identified. It is shown that the key technology area deals with productivity in space, that is, the ability to fabricate and assemble large structures in space, not, as might be expected, with some hardware component technology.

An economic analysis of space solar power and its cost competitiveness as a supplemental source of energy for space and ground markets

NASA Technical Reports Server (NTRS)

Marzwell, N. I.

2002-01-01

Economic Growth has been historically associated with nations that first made use of each new energy source. There is no doubt that Solar Power Satellites is high as a potential energy system for the future. A conceptual cost model of the economics value of space solar power (SSP) as a source of complementary power for in-space and ground applications will be discussed. Several financial analysis will be offered based on present and new technological innovations that may compete with or be complementary to present energy market suppliers depending on various institutional arrangements for government and the private sector in a Global Economy. Any of the systems based on fossil fuels such as coal, oil, natural gas, and synthetic fuels share the problem of being finite resources and are subject to ever-increasing cost as they grow ever more scarce with drastic increase in world population. Increasing world population and requirements from emerging underdeveloped countries will also increase overall demand. This paper would compare the future value of SSP with that of other terrestrial renewable energy in distinct geographic markets within the US, in developing countries, Europe, Asia, and Eastern Europe.

The LEO Archipelago: A system of earth-rings for communications, mass-transport to space, solar power, and control of global warming

NASA Astrophysics Data System (ADS)

Meulenberg, Andrew; Karthik Balaji, P. S.

2011-06-01

Man's quest to get into space is hindered by major problems (e.g., system-development and capital costs, expense of putting mass into orbit, trapped-radiation belts, and environmental impact of a large increase in rocket launches). A multi-purpose low-earth-orbit system of rings circling the earth - the "LEO ARCHIPELAGO TM" - is proposed as a means of solving or bypassing many of them. A fiber-optic ring about the earth would be an initial testing and developmental stage for the Ring Systems, while providing cash-flow through a LEO-based, high-band-width, world-wide communication system. A low-earth-orbit-based space-elevator system, "Sling-on-a-Ring TM", is proposed as the crucial developmental stage of the LEO Archipelago. Being a LEO-based heavy-mass lifter, rather than earth- or GEO-based, it is much less massive and therefore less costly than other proposed space-elevators. With the advent of lower-cost, higher-mass transport to orbit, the options for further space development (e.g., space solar power, radiation, and space-debris dampers, sun shades, and permanent LEO habitation) are greatly expanded. This paper provides an update of the Sling-on-a-Ring concept in terms of new materials, potential applications, and trade-offs associated with an earlier model. The impact of Colossal Carbon Tubes, CCT, a new material with high tensile strength, extremely-low density, and other favorable properties, and other new technologies (e.g., solar-powered lasers, power beaming to near-space and earth, and thermal-control systems) on the development of associated LEO-Ring systems is also explored. The material's effect on the timeline for the system development indicates the feasibility of near-term implementation of the system (possibly within the decade). The Sling-on-a-Ring can provide a less-expensive, environment-friendly mode of access to space. This would pave the way (via eventual operation at >1000 t per day by 2050) for large scale development of space-based technologies.

A perspective about the total solar eclipse observation from future space settlements and a review of Indonesian space researches

NASA Astrophysics Data System (ADS)

Sastradipradja, D.; Dwivany, F. M.; Swandjaja, L.

2016-11-01

Viewing astronomy objects from space is superior to that from Earth due to the absence of terrestrial atmospheric disturbances. Since decades ago, there has been an idea of building gigantic spaceships to live in, i.e., low earth orbit (LEO) settlement. In the context of solar eclipse, the presuming space settlements will accommodate future solar eclipse chasers (amateur or professional astronomers) to observe solar eclipse from space. Not only for scientific purpose, human personal observation from space is also needed for getting aesthetical mental impression. Furthermore, since space science indirectly aids solar eclipse observation, we will discuss the related history and development of Indonesian space experiments. Space science is an essential knowledge to be mastered by all nations.

Workshop on the evolution of the Martian atmosphere

NASA Technical Reports Server (NTRS)

Luhmann, J. G. (Editor); Jakosky, B. M. (Editor)

1992-01-01

Thirty-three papers based on the state of our knowledge prior to the anticipated new results from Mars Observer were presented at the workshop. Because of the nature of the subject, the scope of the papers covered a broad disciplinary range encompassing astronomy and solar physics, geology and geophysics, climatology, atmospheric science, aeronomy, and space physics. The 42 participants heard about topics from the evolution of solar-type stars to candidate instrumentation for measuring escape to space on yet-unscheduled future missions.

ASPOD modifications of 1993-1994

NASA Technical Reports Server (NTRS)

Jackson, Jennifer J. (Editor); Fogarty, Paul W.; Muller, Matthew; Martucci, Thomas A., III; Williams, Daniel; Rowney, David A.

1994-01-01

ASPOD, Autonomous Space Processors for Orbital Debris, provides a unique way of collecting the space debris that has built up over the past 37 years. For the past several years, ASPOD has gone through several different modifications. This year's concentrations were on the solar cutting array, the solar tracker, the earth based main frame/tilt table, the controls for the two robotic arms, and accurate autocad drawings of ASPOD. This final report contains the reports written by the students who worked on the ASPOD project this year.

(?) The Air Force Geophysics Laboratory: Aeronomy, aerospace instrumentation, space physics, meteorology, terrestrial sciences and optical physics

NASA Astrophysics Data System (ADS)

McGinty, A. B.

1982-04-01

Contents: The Air Force Geophysics Laboratory; Aeronomy Division--Upper Atmosphere Composition, Middle Atmosphere Effects, Atmospheric UV Radiation, Satellite Accelerometer Density Measurement, Theoretical Density Studies, Chemical Transport Models, Turbulence and Forcing Functions, Atmospheric Ion Chemistry, Energy Budget Campaign, Kwajalein Reference Atmospheres, 1979, Satellite Studies of the Neutral Atmosphere, Satellite Studies of the Ionosphere, Aerospace Instrumentation Division--Sounding Rocket Program, Satellite Support, Rocket and Satellite Instrumentation; Space Physics Division--Solar Research, Solar Radio Research, Environmental Effects on Space Systems, Solar Proton Event Studies, Defense Meteorological Satellite Program, Ionospheric Effects Research, Spacecraft Charging Technology; Meteorology Division--Cloud Physics, Ground-Based Remote-Sensing Techniques, Mesoscale Observing and Forecasting, Design Climatology, Aircraft Icing Program, Atmospheric Dynamics; Terrestrial Sciences Division--Geodesy and Gravity, Geokinetics; Optical Physics Division--Atmospheric Transmission, Remote Sensing, INfrared Background; and Appendices.

Human exploration of space and power development

NASA Technical Reports Server (NTRS)

Cohen, Aaron

1991-01-01

Reasons for mounting the Space Exploration Initiative, the variables facing U.S. planners, and the developmental technologies that will be needed to support this initiative are discussed. The three more advanced technological approaches in the field of power generation described include a lunar-based solar power system, a geosynchronous-based earth orbit solar power satellite system, and the utilization of helium-3/deuterium fusion reaction to create a nuclear fuel cycle. It is noted that the major elements of the SEI will include a heavy-lift launch vehicle, a transfer vehicle and a descent/ascent vehicle for use on lunar missions and adaptable to Mars exploration.

Systems definition space based power conversion systems: Executive summary

NASA Technical Reports Server (NTRS)

1977-01-01

Potential space-located systems for the generation of electrical power for use on earth were investigated. These systems were of three basic types: (1) systems producing electrical power from solar energy; (2) systems producing electrical power from nuclear reactors; (3) systems for augmenting ground-based solar power plants by orbital sunlight reflectors. Configurations implementing these concepts were developed through an optimization process intended to yield the lowest cost for each. A complete program was developed for each concept, identifying required production rates, quantities of launches, required facilities, etc. Each program was costed in order to provide the electric power cost appropriate to each concept.

A comprehensive solar energy system analysis data base in Huntsville, Alabama

NASA Technical Reports Server (NTRS)

Goddard, J. P.

1978-01-01

The history of a comprehensive solar energy system analysis data base developed by NASA/Marshall Space Flight Center and the University of Alabama is presented, along with its current status. The Marshall Information Retrieval and Data Storage (MIRADS) system was chosen for the data base, and feedback systems were arranged to cope with changes in the needs of the program management for the type of data gathered. The final structure of the data base consists of 22 files divided into 6 topical sections: summaries, climatological, utility rates, architectural, equipment, and economics. The data base offers help to the solar industry in two ways: it provides information and it serves as a model for users trying to establish the climatic and socioeconomic variables they should take into account when they examine a potential market for solar energy equipment.

Expanded Owens Valley Solar Array Science and Data Products

NASA Astrophysics Data System (ADS)

Gary, Dale E.; Hurford, G. J.; Nita, G. M.; Fleishman, G. D.; McTiernan, J. M.

2010-05-01

The Owens Valley Solar Array (OVSA) has been funded for major expansion, to create a university-based facility serving a broad scientific community, to keep the U.S. competitive in the field of solar radio physics. The project, funded by the National Science Foundation through the MRI-Recovery and Reinvestment program, will result in a world-class facility for scientific research at microwave radio frequencies (1-18 GHz) in solar and space weather physics. The project also includes an exciting program of targeted astronomical science. The solar science to be addressed focuses on the magnetic structure of the solar corona, on transient phenomena resulting from magnetic interactions, including the sudden release of energy and subsequent particle acceleration and heating, and on space weather phenomena. The project will support the scientific community by providing open data access and software tools for analysis of the data, to exploit synergies with on-going solar research in other wavelength bands. The New Jersey Institute of Technology (NJIT) will upgrade OVSA from its current complement of 7 antennas to a total of 15 by adding 8 new antennas, and will reinvest in the existing infrastructure by replacing the existing control systems, signal transmission, and signal processing with modern, far more capable and reliable systems based on new technology developed for the Frequency Agile Solar Radiotelescope (FASR). The project will be completed in time to provide solar-dedicated observations during the upcoming solar maximum in 2013 and beyond. We will detail the new science addressed by the expanded array, and provide an overview of the expected data products.

Coronal Mass Ejections (CMEs) and Associated Phenomena

NASA Astrophysics Data System (ADS)

Manoharan, P. K.

2008-10-01

The Sun is the most powerful radio waves emitting object in the sky. The first documented recognition of the reception of radio waves from the Sun was made in 1942 by Hey.15 Since then solar radio observations, from ground-based and space-based instruments, have played a major role in understanding the physics of the Sun and fundamental physical processes of the solar radio emitting phenomena...

Strategic Plans for the Future of Solar Physics: a community discussion of the NASA Sun-Earth Connection Program Roadmap and the NAS Decadal Survey of Astronomy and Astrophysics (Solar Astronomy section)

NASA Astrophysics Data System (ADS)

Schrijver, K.; Knoelker, M.

1999-05-01

The NASA Sun-Earth Connections Program is currently revising its Roadmap, the long-range plan for science goals, technology development, and missions between 2000 and 2040. From the interior dynamics of the Sun, to the interactions of plasma, fields, and radiation in the photosphere and solar atmosphere, to the heating and structure of the corona, to the acceleration, structure, and evolution of the solar wind, to the interactions of the heliosphere with the interstellar medium, to the processes of solar, stellar, and solar system evolution - progress in each of these domains will help us understand how the Sun impacts our home in space. The Roadmap Committee is seeking to refine and extend the SEC's vision and identify the milestone missions for the future. During this session, an outline of the current draft Roadmap will be presented, and further community involvement will be solicited to ensure the strongest possible concensus on the revised Roadmap. The National Academy of Sciences' Space Science Board has appointed a committee to perform a Decadal Survey of Astronomy and Astrophysics, which is surveying the field of space- and ground-based astronomy and astrophysics, recommending priorities for the most important new initiatives of the decade 2000-2010. The prioritization delivered by the earlier Decadal Surveys has played an important role in guiding the funding agencies in setting their priorities for astronomy and astrophysics. Therefore it will be of crucial importance for solar physics to contribute a strong case for its own set of future projects to be incorpoprated into the survey. The solar physics of the next decade will be characterized by its increasing societal relevance in the context of the National Space Weather Program and related issues, as well as its classical importance as a ``base" for many astrophysical questions. The presentation and subsequent discussion at the Chicago meeting is intended to solicit further community input, to achieve optimal representation for solar physics in the Decadal Survey. The Roadmap Committee and the Decadal Survey's solar panel encourage the whole solar physics community to contact them prior to the meeting. The list of the committee/panel members and their e-mail addresses, as well as related information, can be accessed via their websites at http://www.lmsal.com/sec/ and http://www.nas.edu/bpa/projects/astrosurvey/solar/ , respectively.

Mitigating Aviation Communication and Satellite Orbit Operations Surprises from Adverse Space Weather

NASA Technical Reports Server (NTRS)

Tobiska, W. Kent

2008-01-01

Adverse space weather affects operational activities in aviation and satellite systems. For example, large solar flares create highly variable enhanced neutral atmosphere and ionosphere electron density regions. These regions impact aviation communication frequencies as well as precision orbit determination. The natural space environment, with its dynamic space weather variability, is additionally changed by human activity. The increase in orbital debris in low Earth orbit (LEO), combined with lower atmosphere CO2 that rises into the lower thermosphere and causes increased cooling that results in increased debris lifetime, adds to the environmental hazards of navigating in near-Earth space. This is at a time when commercial space endeavors are posed to begin more missions to LEO during the rise of the solar activity cycle toward the next maximum (2012). For satellite and aviation operators, adverse space weather results in greater expenses for orbit management, more communication outages or aviation and ground-based high frequency radio used, and an inability to effectively plan missions or service customers with space-based communication, imagery, and data transferal during time-critical activities. Examples of some revenue-impacting conditions and solutions for mitigating adverse space weather are offered.

FeatherSail - Design, Development and Future Impact

NASA Technical Reports Server (NTRS)

Alhorn, Dean C.; Scheierl, J. M.

2010-01-01

To the present day, the idea of using solar sails for space propulsion is still just a concept, but one that provides a great potential for future space exploration missions. Several notable solar propulsion missions and experiments have been performed and more are still in the development stage. Solar Sailing is a method of space flight propulsion, which utilizes the light photons to propel spacecrafts through the vacuum of space. This concept will be tested in the near future with the launch of the NanoSail-D satellite. NanoSail-D is a nano-class satellite, <10kg, which will deploy a thin lightweight sheet of reflective material used to propel the satellite in its low earth orbit. Using the features of the NanoSail-D architecture, a second-generation solar sail design concept, dubbed FeatherSail, has been developed. The goal of the FeatherSail project is to create a sail vehicle with the ability to provide steering from the sails and increase the areal density. The FeatherSail design will utilize the NanoSail-D based extendable boom technology with only one sail on each set of booms. This design also allows each of the four sails to feather as much as ninety degrees. The FeatherSail concept uses deployable solar arrays to generate the power necessary for deep space missions. In addition, recent developments in low power, low temperature Silicon-Germanium electronics provide the capability for long duration deep space missions. It is envisioned that the FeatherSail conceptual design will provide the impetus for future sail vehicles, which may someday visit distant places that mankind has only observed.

International ultraviolet explorer solar array power degradation

NASA Technical Reports Server (NTRS)

Day, J. H., Jr.

1983-01-01

The characteristic electrical performance of each International Ultraviolet Explorer (IUE) solar array panel is evaluated as a function of several prevailing variables (namely, solar illumination, array temperature and solar cell radiation damage). Based on degradation in the current-voltage characteristics of the array due to solar cell damage accumulated over time by space charged particle radiations, the available IUE solar array power is determined for life goals up to 10 years. Best and worst case calculations are normalized to actual IUE flight data (available solar array power versus observatory position) to accurately predict the future IUE solar array output. It is shown that the IUE solar array can continue to produce more power than is required at most observatory positions for at least 5 more years.

A space-to-space microwave wireless power transmission experiential mission using small satellites

NASA Astrophysics Data System (ADS)

Bergsrud, Corey; Straub, Jeremy

2014-10-01

A space solar microwave power transfer system (SSMPTS) may represent a paradigm shift to how space missions in Earth orbit are designed. A SSMPTS may allow a smaller receiving surface to be utilized on the receiving craft due to the higher-density power transfer (compared to direct solar flux) from a SSMPTS supplier craft; the receiving system is also more efficient and requires less mass and volume. The SSMPTS approach also increases mission lifetime, as antenna systems do not degrade nearly as quickly as solar panels. The SSMPTS supplier craft (instead) can be replaced as its solar panels degrade, a mechanism for replacing panels can be utilized or the SSMPTS can be maneuvered closer to a subset of consumer spacecraft. SSMPTS can also be utilized to supply power to spacecraft in eclipse and to supply variable amounts of power, based on current mission needs, to power the craft or augment other power systems. A minimal level of orbital demonstrations of SSP technologies have occurred. A mission is planned to demonstrate and characterize the efficacy of space-to-space microwave wireless power transfer. This paper presents an overview of this prospective mission. It then discusses the spacecraft system (comprised of an ESPA/SmallSat-class spacecraft and a 1-U CubeSat), launch options, mission operations and the process of evaluating mission outcomes.

Replacement Capability Options for the United States Space Shuttle

DTIC Science & Technology

2013-09-01

extended periods, and to expand our knowledge of solar astronomy well beyond Earth-based observations.” During the Skylab missions, both the man...determined Skylab’s orbit was no longer stable due to higher than predicted solar activity. Therefore, Skylab had to be de-orbited earlier than...Module houses the oxygen, life support, power, communications, thermal control, and propulsions systems. The solar arrays for the Soyuz are also

Space construction system analysis study: Project systems and missions descriptions

NASA Technical Reports Server (NTRS)

1979-01-01

Three project systems are defined and summarized. The systems are: (1) a Solar Power Satellite (SPS) Development Flight Test Vehicle configured for fabrication and compatible with solar electric propulsion orbit transfer; (2) an Advanced Communications Platform configured for space fabrication and compatible with low thrust chemical orbit transfer propulsion; and (3) the same Platform, configured to be space erectable but still compatible with low thrust chemical orbit transfer propulsion. These project systems are intended to serve as configuration models for use in detailed analyses of space construction techniques and processes. They represent feasible concepts for real projects; real in the sense that they are realistic contenders on the list of candidate missions currently projected for the national space program. Thus, they represent reasonable configurations upon which to base early studies of alternative space construction processes.

The role of MEXART in the National Space Weather Laboratory of Mexico: Detection of solar wind, CMEs, ionosphere, active regions and flares.

NASA Astrophysics Data System (ADS)

Mejia-Ambriz, J.; Gonzalez-Esparza, A.; De la Luz, V.; Villanueva-Hernandez, P.; Andrade, E.; Aguilar-Rodriguez, E.; Chang, O.; Romero Hernandez, E.; Sergeeva, M. A.; Perez Alanis, C. A.; Reyes-Marin, P. A.

2017-12-01

The National Space Weather Laboratory - Laboratorio Nacional de Clima Espacial (LANCE) - of Mexico has different ground based instruments to study and monitor the space weather. One of these instruments is the Mexican Array Radio Telescope (MEXART) which is principally dedicated to remote sensing the solar wind and coronal mass ejections (CMEs) at 140 MHz, the instrument can detect solar wind densities and speeds from about 0.4 to 1 AU by modeling observations of interplanetary scintillation (IPS). MEXART is also able to detect ionospheric disturbances associated with transient space weather events by the analysis of ionospheric scintillation (IONS) . Additionally, MEXART has followed the Sun since the beginning of the current Solar Cycle 24 with records of 8 minutes per day, and occasionally, has partially detected the process of strong solar flares. Here we show the contributions of MEXART to the LANCE by reporting recent detections of CMEs by IPS, the arrive of transient events at Earth by IONS, the influence of active regions in the flux of the Sun at 140 MHz and the detection of a M6.5 class flare. Furthermore we report the status of a near real time analysis of IPS data for forecast purposes and the potential contribution to the Worldwide IPS Stations network (WIPSS), which is an effort to achieve a better coverage of the solar wind observations in the inner heliosphere.

Characterizing the Radiation Survivability of Space Solar Cell Technologies for Heliospheric Missions

NASA Astrophysics Data System (ADS)

Lee, J. H.; Walker, D.; Mann, C. J.; Yue, Y.; Nocerino, J. C.; Smith, B. S.; Mulligan, T.

2016-12-01

Space solar cells are responsible for powering the majority of heliospheric space missions. This paper will discuss methods for characterizing space solar cell technologies for on-orbit operations that rely on a series of laboratory tests that include measuring the solar cells' beginning of life performance under simulated (e.g. AM0 or air mass zero) sunlight over different operating temperatures and observing their end of life performance following exposure to laboratory-generated charged particle radiation (protons and electrons). The Aerospace Corporation operates a proton implanter as well as electron gun facilities and collaborates with external radiation effects facilities to expose space solar cells or other space technologies to representative space radiation environments (i.e. heliosphere or magnetosphere of Earth or other planets), with goals of characterizing how the technologies perform over an anticipated space mission timeline and, through the application of precision diagnostic capabilities, understanding what part of the solar cell is impacted by varying space radiation environments. More recently, Aerospace has been hosting solar cell flight tests on its previously-flown CubeSat avionics bus, providing opportunities to compare the laboratory tests to on-orbit observations. We hope through discussion of the lessons learned and methods we use to characterize how solar cells perform after space radiation exposure that similar methodology could be adopted by others to improve the state of knowledge on the survivability of other space technologies required for future space missions.

Solar array electrical performance assessment for Space Station Freedom

NASA Technical Reports Server (NTRS)

Smith, Bryan K.; Brisco, Holly

1993-01-01

Electrical power for Space Station Freedom will be generated by large Photovoltaic arrays with a beginning of life power requirement of 30.8 kW per array. The solar arrays will operate in a Low Earth Orbit (LEO) over a design life of fifteen years. This paper provides an analysis of the predicted solar array electrical performance over the design life and presents a summary of supporting analysis and test data for the assigned model parameters and performance loss factors. Each model parameter and loss factor is assessed based upon program requirements, component analysis, and test data to date. A description of the LMSC performance model, future test plans, and predicted performance ranges are also given.

Solar array electrical performance assessment for Space Station Freedom

NASA Technical Reports Server (NTRS)

Smith, Bryan K.; Brisco, Holly

1993-01-01

Electrical power for Space Station Freedom will be generated by large photovoltaic arrays with a beginning of life power requirement of 30.8 kW per array. The solar arrays will operate in a Low Earth Orbit (LEO) over a design life of fifteen years. This paper provides an analysis of the predicted solar array electrical performance over the design life and presents a summary of supporting analysis and test data for the assigned model parameters and performance loss factors. Each model parameter and loss factor is assessed based upon program requirements, component analysis and test data to date. A description of the LMSC performance model future test plans and predicted performance ranges are also given.

Annealing characteristics of irradiated hydrogenated amorphous silicon solar cells

NASA Technical Reports Server (NTRS)

Payson, J. S.; Abdulaziz, S.; Li, Y.; Woodyard, J. R.

1991-01-01

It was shown that 1 MeV proton irradiation with fluences of 1.25E14 and 1.25E15/sq cm reduces the normalized I(sub SC) of a-Si:H solar cell. Solar cells recently fabricated showed superior radiation tolerance compared with cells fabricated four years ago; the improvement is probably due to the fact that the new cells are thinner and fabricated from improved materials. Room temperature annealing was observed for the first time in both new and old cells. New cells anneal at a faster rate than old cells for the same fluence. From the annealing work it is apparent that there are at least two types of defects and/or annealing mechanisms. One cell had improved I-V characteristics following irradiation as compared to the virgin cell. The work shows that the photothermal deflection spectroscopy (PDS) and annealing measurements may be used to predict the qualitative behavior of a-Si:H solar cells. It was anticipated that the modeling work will quantitatively link thin film measurements with solar cell properties. Quantitative predictions of the operation of a-Si:H solar cells in a space environment will require a knowledge of the defect creation mechanisms, defect structures, role of defects on degradation, and defect passivation and annealing mechanisms. The engineering data and knowledge base for justifying space flight testing of a-Si:H alloy based solar cells is being developed.

20th National Solar Physics Meeting

NASA Astrophysics Data System (ADS)

Dorotovic, Ivan

2010-12-01

These proceedings (ISBN: 978-80-85221-68-8) provide an overview of current research on solar physics, geophysics and space weather in the astronomical, geophysical and space physics institutions in the Slovak Republic and the Czech Republic. Several researchers from other countries participated in the meeting as well. The different parts address: solar interior, solar photosphere, chromosphere, corona, total solar eclipses, space weather, instrumentation. Most of the papers are published in Slovak and Czech, respectively. The proceedings are intended for researchers, graduate and PhD. students, workers of astronomical observatories interested in solar physics, geophysics and space weather.

Development of gridded solar radiation data over Belgium based on Meteosat and in-situ observations

NASA Astrophysics Data System (ADS)

Journée, Michel; Vanderveken, Gilles; Bertrand, Cédric

2013-04-01

Knowledge on solar resources is highly important for all forms of solar energy applications. With the recent development in solar-based technologies national meteorological services are faced with increasing demands for high-quality and reliable site-time specific solar resource information. Traditionally, solar radiation is observed by means of networks of meteorological stations. Costs for installation and maintenance of such networks are very high and national networks comprise only few stations. Consequently the availability of ground-based solar radiation measurements has proven to be spatially and temporally inadequate for many applications. To overcome such a limitation, a major effort has been undertaken at the Royal Meteorological Institute of Belgium (RMI) to provide the solar energy industry, the electricity sector, governments, and renewable energy organizations and institutions with the most suitable and accurate information on the solar radiation resources at the Earth's surface over the Belgian territory. Only space-based observations can deliver a global coverage of the solar irradiation impinging on horizontal surface at the ground level. Because only geostationary data allow to capture the diurnal cycle of the solar irradiance at the Earth's surface, a method that combines information from Meteosat Second Generation satellites and ground-measurement has been implemented at RMI to generate high resolution solar products over Belgium on an operational basis. Besides these new products, the annual and seasonal variability of solar energy resource was evaluated, solar radiation climate zones were defined and the recent trend in solar radiation was characterized.

Space Solar Power Satellite Technology Development at the Glenn Research Center: An Overview

NASA Technical Reports Server (NTRS)

Dudenhoefer, James E.; George, Patrick J.

2000-01-01

NASA Glenn Research Center (GRC). is participating in the Space Solar Power Exploratory Research and Technology program (SERT) for the development of a solar power satellite concept. The aim of the program is to provide electrical power to Earth by converting the Sun's energy and beaming it to the surface. This paper will give an overall view of the technologies being pursued at GRC including thin film photovoltaics, solar dynamic power systems, space environmental effects, power management and distribution, and electric propulsion. The developmental path not only provides solutions to gigawatt sized space power systems for the future, but provides synergistic opportunities for contemporary space power architectures. More details of Space Solar Power can be found by reading the references sited in this paper and by connecting to the web site http://moonbase.msfc.nasa.gov/ and accessing the "Space Solar Power" section "Public Access" area.

The solar wind-magnetosphere-ionosphere system

PubMed

Lyon

2000-06-16

The solar wind, magnetosphere, and ionosphere form a single system driven by the transfer of energy and momentum from the solar wind to the magnetosphere and ionosphere. Variations in the solar wind can lead to disruptions of space- and ground-based systems caused by enhanced currents flowing into the ionosphere and increased radiation in the near-Earth environment. The coupling between the solar wind and the magnetosphere is mediated and controlled by the magnetic field in the solar wind through the process of magnetic reconnection. Understanding of the global behavior of this system has improved markedly in the recent past from coordinated observations with a constellation of satellite and ground instruments.

Study of extraterrestrial disposal of radioactive wastes. Part 2: Preliminary feasibility screening study of extraterrestrial disposal of radioactive wastes in concentrations, matrix materials, and containers designed for storage on earth

NASA Technical Reports Server (NTRS)

Hyland, R. E.; Wohl, M. L.; Thompson, R. L.; Finnegan, P. M.

1972-01-01

The results are reported of a preliminary feasibility screening study for providing long-term solutions to the problems of handling and managing radioactive wastes by extraterrestrial transportation of the wastes. Matrix materials and containers are discussed along with payloads, costs, and destinations for candidate space vehicles. The conclusions reached are: (1) Matrix material such as spray melt can be used without exceeding temperature limits of the matrix. (2) The cost in mills per kw hr electric, of space disposal of fission products is 4, 5, and 28 mills per kw hr for earth escape, solar orbit, and solar escape, respectively. (3) A major factor effecting cost is the earth storage time. Based on a normal operating condition design for solar escape, a storage time of more than sixty years is required to make the space disposal charge less than 10% of the bus-bar electric cost. (4) Based on a 10 year earth storage without further processing, the number of shuttle launches required would exceed one per day.

Thermo-electronic solar power conversion with a parabolic concentrator

NASA Astrophysics Data System (ADS)

Olukunle, Olawole C.; De, Dilip K.

2016-02-01

We consider the energy dynamics of the power generation from the sun when the solar energy is concentrated on to the emitter of a thermo-electronic converter with the help of a parabolic mirror. We use the modified Richardson-Dushman equation. The emitter cross section is assumed to be exactly equal to the focused area at a height h from the base of the mirror to prevent loss of efficiency. We report the variation of output power with solar insolation, height h, reflectivity of the mirror, and anode temperature, initially assuming that there is no space charge effect. Our methodology allows us to predict the temperature at which the anode must be cooled in order to prevent loss of efficiency of power conversion. Novel ways of tackling the space charge problem have been discussed. The space charge effect is modeled through the introduction of a parameter f (0 < f < 1) in the thermos-electron emission equation. We find that the efficiency of the power conversion depends on solar insolation, height h, apart from radii R of the concentrator aperture and emitter, and the collector material properties. We have also considered solar thermos electronic power conversion by using single atom-layer graphene as an emitter.

Analysis of the effects of simulated synergistic LEO environment on solar panels

NASA Astrophysics Data System (ADS)

Allegri, G.; Corradi, S.; Marchetti, M.; Scaglione, S.

2007-02-01

The effects due to the LEO environment exposure of a solar array primary structure are here presented and discussed in detail. The synergistic damaging components featuring LEO environment are high vacuum, thermal cycling, neutral gas, ultraviolet (UV) radiation and cold plasma. The synergistic effects due to these environmental elements are simulated by "on ground" tests, performed in the Space Environment Simulator (SAS) at the University of Rome "La Sapienza"; numerical simulations are performed by the Space Environment Information System (SPENVIS), developed by the European Space Agency (ESA). A "safe life" design for a solar array primary structure is developed, taking into consideration the combined damaging action of the LEO environment components; therefore results from both numerical and experimental simulations are coupled within the framework of a standard finite element method (FEM) based design. The expected durability of the solar array primary structure, made of laminated sandwich composite, is evaluated assuming that the loads exerted on the structure itself are essentially dependent on thermo-elastic stresses. The optical degradation of surface materials and the stiffness and strength degradation of structural elements are taken into account to assess the global structural durability of the solar array under characteristic operative conditions in LEO environment.

Image-based optimization of coronal magnetic field models for improved space weather forecasting

NASA Astrophysics Data System (ADS)

Uritsky, V. M.; Davila, J. M.; Jones, S. I.; MacNeice, P. J.

2017-12-01

The existing space weather forecasting frameworks show a significant dependence on the accuracy of the photospheric magnetograms and the extrapolation models used to reconstruct the magnetic filed in the solar corona. Minor uncertainties in the magnetic field magnitude and direction near the Sun, when propagated through the heliosphere, can lead to unacceptible prediction errors at 1 AU. We argue that ground based and satellite coronagraph images can provide valid geometric constraints that could be used for improving coronal magnetic field extrapolation results, enabling more reliable forecasts of extreme space weather events such as major CMEs. In contrast to the previously developed loop segmentation codes designed for detecting compact closed-field structures above solar active regions, we focus on the large-scale geometry of the open-field coronal regions up to 1-2 solar radii above the photosphere. By applying the developed image processing techniques to high-resolution Mauna Loa Solar Observatory images, we perform an optimized 3D B-line tracing for a full Carrington rotation using the magnetic field extrapolation code developed S. Jones at al. (ApJ 2016, 2017). Our tracing results are shown to be in a good qualitative agreement with the large-scale configuration of the optical corona, and lead to a more consistent reconstruction of the large-scale coronal magnetic field geometry, and potentially more accurate global heliospheric simulation results. Several upcoming data products for the space weather forecasting community will be also discussed.

Manufacturing with the Sun

NASA Astrophysics Data System (ADS)

Murphy, L. M.; Hauser, S. G.; Clyne, R. J.

1992-05-01

Concentrated solar radiation is now a viable alternative energy source for many advanced manufacturing processes. Researchers at the National Renewable Energy Laboratory (NREL) have demonstrated the feasibility of processes such as solar-induced surface transformation of materials (SISTM), solar-based manufacturing, and solar-pumped lasers. Researchers are also using sunlight to decontaminate water and soils polluted with organic compounds; these techniques could provide manufacturers with innovative alternatives to traditional methods of waste management. The solar technology that is now being integrated into today's manufacturing processes offers even greater potential for tomorrow, especially as applied to the radiation-abundant environment available in space and on the lunar surface.

Manufacturing with the Sun

NASA Astrophysics Data System (ADS)

Murphy, Lawrence M.; Hauser, Steven G.; Clyne, Richard J.

1991-12-01

Concentrated solar radiation is now a viable alternative source for many advanced manufacturing processes. Researchers at the National Renewable Energy Laboratory (NREL) have demonstrated the feasibility of processes such as solar induced surface transformation of materials (SISTM), solar based manufacturing, and solar pumped lasers. Researchers are also using sunlight to decontaminate water and soils polluted with organic compounds; these techniques could provide manufacturers with innovative alternatives to traditional methods of waste management. The solar technology that is now being integrated into today's manufacturing processes offer greater potential for tomorrow, especially as applied to the radiation abundant environment available in space and on the lunar surface.

Manufacturing with the Sun

NASA Technical Reports Server (NTRS)

Murphy, Lawrence M.; Hauser, Steven G.; Clyne, Richard J.

1991-01-01

Concentrated solar radiation is now a viable alternative source for many advanced manufacturing processes. Researchers at the National Renewable Energy Laboratory (NREL) have demonstrated the feasibility of processes such as solar induced surface transformation of materials (SISTM), solar based manufacturing, and solar pumped lasers. Researchers are also using sunlight to decontaminate water and soils polluted with organic compounds; these techniques could provide manufacturers with innovative alternatives to traditional methods of waste management. The solar technology that is now being integrated into today's manufacturing processes offer greater potential for tomorrow, especially as applied to the radiation abundant environment available in space and on the lunar surface.

Solar-B E/PO Program at Chabot Space and Science Center, Oakland, California

NASA Astrophysics Data System (ADS)

Burress, B. S.

2005-05-01

Chabot Space and Science Center in Oakland, California, conducts the Education/Public Outreach program for the Lockheed-Martin Solar and Astrophysics Lab Solar-B Focal Plane Package project. Since opening its doors in August 2000, Chabot has carried out this program in activities and educational products in the public outreach, informal education, and formal education spheres. We propose a poster presentation that illustrates the spectrum of our Solar-B E/PO program. Solar-B, scheduled to launch in September 2006, is another step in an increasingly sophisticated investigation and understanding of our Sun, its behavior, and its effects on the Earth and our technological civilization. A mission of the Japan Aerospace Exploration Agency (JAXA), Solar-B is an international collaboration between Japan, the US/NASA, and the UK/PPARC. Solar-B's main optical telescope, extreme ultraviolet imaging spectrometer, and x-ray telescope will collect data on the Sun's magnetic dynamics from the photosphere through the corona at higher spatial and time resolution than on current and previous solar satellite missions, furthering our understanding of the Sun's behavior and, ultimately, its effects on the Earth. Chabot's E/PO program for the Lockheed-Martin Solar-B Focal Plane Package is multi-faceted, including elements focused on technology/engineering, solar physics, and Sun-Earth Connection themes. In the Public Outreach arena, we conduct events surrounding NASA Sun-Earth Day themes and programs other live and/or interactive events, facilitate live solar viewing, and present a series of exhibits focused on the Solar-B and other space-based missions, the dynamic Sun, and light and optics. In the Informal Education sector we run a solar day camp for kids and produce educational products, including a poster on the Solar-B mission and CDROM multimedia packages. In Formal Education, we develop classroom curriculum guides and conduct workshops training teachers in their implementation. Our poster presentation will address the highlights of our program in all three of these areas.

Solar EUV irradiance from the San Marco ASSI - A reference spectrum

NASA Technical Reports Server (NTRS)

Schmidtke, Gerhard; Woods, Thomas N.; Worden, John; Rottman, Gary J.; Doll, Harry; Wita, Claus; Solomon, Stanley C.

1992-01-01

The only satellite measurement of the solar EUV irradiance during solar cycle 22 has been obtained with the Airglow Solar Spectrometer Instrument (ASSI) aboard the San Marco 5 satellite flown in 1988. The ASSI in-flight calibration parameters are established by using the internal capabilities of ASSI and by comparing ASSI results to the results from other space-based experiments on the ASSI calibration rocket and the Solar Mesospheric Explorer (SME). A solar EUV irradiance spectrum derived from ASSI observations on November 10, 1988 is presented as a reference spectrum for moderate solar activity for the aeronomy community. This ASSI spectrum should be considered as a refinement and extension of the solar EUV spectrum published for the same day by Woods and Rottman (1990).

Photovoltaic Engineering Testbed Designed for Calibrating Photovoltaic Devices in Space

NASA Technical Reports Server (NTRS)

Landis, Geoffrey A.

2002-01-01

Accurate prediction of the performance of solar arrays in space requires that the cells be tested in comparison with a space-flown standard. Recognizing that improvements in future solar cell technology will require an ever-increasing fidelity of standards, the Photovoltaics and Space Environment Branch at the NASA Glenn Research Center, in collaboration with the Ohio Aerospace Institute, designed a prototype facility to allow routine calibration, measurement, and qualification of solar cells on the International Space Station, and then the return of the cells to Earth for laboratory use. For solar cell testing, the Photovoltaic Engineering Testbed (PET) site provides a true air-mass-zero (AM0) solar spectrum. This allows solar cells to be accurately calibrated using the full spectrum of the Sun.

The Projection of Space Radiation Environments with a Solar Cycle Statistical Model

NASA Technical Reports Server (NTRS)

Kim, Myung-Hee; Cucinotta, Francis A.; Wilson, John W.

2006-01-01

A solar cycle statistical model has been developed to project sunspot numbers which represent the variations in the space radiation environment. The resultant projection of sunspot numbers in near future were coupled to space-related quantities of interest in radiation protection, such as the galactic cosmic radiation (GCR) deceleration potential (f) and the mean occurrence frequency of solar particle event (SPE). Future GCR fluxes have been derived from a predictive model, in which GCR temporal dependence represented by f was derived from GCR flux and ground-based Climax neutron monitor rate measurements over the last four decades. Results showed that the point dose equivalent inside a typical spacecraft in interplanetary radiation fields was influenced by solar modulation up to a factor of three. One important characteristic of sporadic SPEs is their mean frequency of occurrence, which is dependent on solar activity. Projections of future mean frequency of SPE occurrence were estimated from a power law function of sunspot number. Furthermore, the cumulative probabilities of SPE during short-period missions were defined with the continuous database of proton fluences of SPE. The analytic representation of energy spectra of SPE was constructed by the Weibull distribution for different event sizes. The representative exposure level at each event size was estimated for the guideline of protection systems for astronauts during future space exploration missions.

Impacts of Stratospheric Dynamics on Atmospheric Behavior from the Ground to Space Solar Minimum and Solar Maximum

DTIC Science & Technology

2015-12-15

from the ground to space solar minimum and solar maximum 5a. CONTRACT NUMBER BAA-76-11-01 5b. GRANT NUMBER N00173-12-1G010 5c. PROGRAM ELEMENT...atmospheric behavior from the ground to space under solar minimum and solar maximum conditions (Contract No.: N00173-12-1-G010 NRL) Project Summary...Dynamical response to solar radiative forcing is a crucial and poorly understood mechanisms. We propose to study the impacts of large dynamical events

The JPL space photovoltaic program. [energy efficient so1 silicon solar cells for space applications

NASA Technical Reports Server (NTRS)

Scott-Monck, J. A.

1979-01-01

The development of energy efficient solar cells for space applications is discussed. The electrical performance of solar cells as a function of temperature and solar intensity and the influence of radiation and subsequent thermal annealing on the electrical behavior of cells are among the factors studied. Progress in GaAs solar cell development is reported with emphasis on improvement of output power and radiation resistance to demonstrate a solar cell array to meet the specific power and stability requirements of solar power satellites.

Modeling and Analysis of Geoelectric Fields: Extended Solar Shield

NASA Astrophysics Data System (ADS)

Ngwira, C. M.; Pulkkinen, A. A.

2016-12-01

In the NASA Applied Sciences Program Solar Shield project, an unprecedented first-principles-based system to forecast geomagnetically induced current (GIC) in high-voltage power transmission systems was developed. Rapid progress in the field of numerical physics-based space environment modeling has led to major developments over the past few years. In this study modeling and analysis of induced geoelectric fields is discussed. Specifically, we focus on the successful incorporation of 3-D EM transfer functions in the modeling of E-fields, and on the analysis of near real-time simulation outputs used in the Solar Shield forecast system. The extended Solar Shield is a collaborative project between DHS, NASA, NOAA, CUA and EPRI.

The MHD simulation of interplanetary space and heliosphere by using the boundary conditions of time-varying magnetic field and IPS-based plasma

NASA Astrophysics Data System (ADS)

Hayashi, K.; Tokumaru, M.; Kojima, M.; Fujiki, K.

2008-12-01

We present our new boundary treatment to introduce the temporal variation of the observation-based magnetic field and plasma parameters on the inner boundary sphere (at 30 to 50 Rs) to the MHD simulation of the interplanetary space and the simulation results. The boundary treatment to induce the time-variation of the magnetic field including the radial component is essentially same as shown in our previous AGU meetings and newly modified so that the model can also include the variation of the plasma variables detected by IPS (interplanetary scintillation) observation, a ground-based remote sensing technique for the solar wind plasma. We used the WSO (Wilcox Solar Observatory at Stanford University) for the solar magnetic field input. By using the time-varying boundary condition, smooth variations of heliospheric MHD variables during the several Carrington solar rotation period are obtained. The simulation movie will show how the changes in the inner heliosphere observable by the ground-based instrument propagate outward and affects the outer heliosphere. The simulated MHD variables are compared with the Ulysses in-situ measurement data including ones made during its travel from the Earth to Jupiter for validation, and we obtain better agreements than with the simulation with fixed boundary conditions.

Terrestrial Planet Space Weather Information: An Update

NASA Astrophysics Data System (ADS)

Luhmann, J. G.; Li, Y.; Lee, C.; Mays, M. L.; Odstrcil, D.; Jian, L.; Galvin, A. B.; Mewaldt, R. A.; von Rosenvinge, T. T.; Russell, C. T.; Halekas, J. S.; Connerney, J. E. P.; Jakosky, B. M.; Thompson, W. T.; Baker, D. N.; Dewey, R. M.; Zheng, Y.; Holmstrom, M.; Futaana, Y.

2015-12-01

Space weather research is now a solar system-wide enterprise. While with the end of the Venus Express Express mission and MESSENGER, we lost our 'inside' sentinels, new missions such as Solar Orbiter and SPP, and Bepi-Colombo will soon be launched and operating. In the meantime the combination of L1 resources (ACE,WIND,SOHO) and STEREO-A at 1 AU, and Mars Express and MAVEN missions at ~1.5 AU, provide opportunities. Comparative conditions at the Earth orbit and Mars orbit locations are of special interest because they are separated by the region where most solar wind stream interaction regions develop. These alter the propagation of disturbances including the interplanetary CME-driven shocks that make the space radiation affecting future Human mission planning. We share some observational and modeling results thatillustrate present capabilities, as well as developing ones such as ENLIL-based SEP event models that use a range of available observations.

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.

TROPIX: A solar electric propulsion flight experiment

NASA Technical Reports Server (NTRS)

Hickman, J. Mark; Hillard, G. Barry; Oleson, Steven R.

1993-01-01

The Transfer Orbit Plasma Interaction Experiment (TROPIX) is a proposed scientific experiment and flight demonstration of a solar electric propulsion vehicle. Its mission goals are to significantly increase our knowledge of Earth's magnetosphere and its associated plasma environment and to demonstrate an operational solar electric upper stage (SEUS) for small launch vehicles. The scientific investigations and flight demonstration technology experiments are uniquely interrelated because of the spacecraft's interaction with the surrounding environment. The data obtained will complement previous studies of the Earth's magnetosphere and space plasma environment by supplying the knowledge necessary to attain the strategic objectives of the NASA Office of Space Science. This first operational use of a primary ion propulsion vehicle, designed to withstand the harsh environments from low Earth orbit to geosynchronous Earth orbit, may lead to the development of a new class of electric propulsion upper stages or space-based transfer vehicles and may improve future spacecraft design and safety.

The scientific challenges to forecasting the propagation of space weather through the heliosphere (Invited)

NASA Astrophysics Data System (ADS)

van der Holst, B.; Manchester, W.; Sokolov, I.; Toth, G.; Gombosi, T. I.

2013-12-01

Coronal mass ejections (CMEs) are a major source of potentially destructive space weather conditions. Understanding and forecasting these events are of utmost importance. In this presentation we discuss the progress towards a physics-based predictive capability within the Space Weather Modeling Framework (SWMF). We demonstrate our latest development in the AWSoM (Alfven Wave Solar Model) global model of the solar corona and inner heliosphere. This model accounts for the coupled thermodynamics of the electrons and protons via single fluid magnetohydrodynamics. The coronal heating and solar wind acceleration are addressed with Alfvén wave turbulence. The realistic 3D magnetic field is simulated using data from the photospheric magnetic field measurements. The AWSoM model serves as a workhorse for modeling CMEs from initial eruption to prediction at 1AU. With selected events we will demonstrate the complexity and challenges associated with CME propagation.

Optimal design study of high efficiency indium phosphide space solar cells

NASA Technical Reports Server (NTRS)

Jain, Raj K.; Flood, Dennis J.

1990-01-01

Recently indium phosphide solar cells have achieved beginning of life AMO efficiencies in excess of 19 pct. at 25 C. The high efficiency prospects along with superb radiation tolerance make indium phosphide a leading material for space power requirements. To achieve cost effectiveness, practical cell efficiencies have to be raised to near theoretical limits and thin film indium phosphide cells need to be developed. The optimal design study is described of high efficiency indium phosphide solar cells for space power applications using the PC-1D computer program. It is shown that cells with efficiencies over 22 pct. AMO at 25 C could be fabricated by achieving proper material and process parameters. It is observed that further improvements in cell material and process parameters could lead to experimental cell efficiencies near theoretical limits. The effect of various emitter and base parameters on cell performance was studied.

Space Sciences Education and Outreach Project of Moscow State University

NASA Astrophysics Data System (ADS)

Krasotkin, S.

2006-11-01

sergekras@mail.ru The space sciences education and outreach project was initiated at Moscow State University in order to incorporate modern space research into the curriculum popularize the basics of space physics, and enhance public interest in space exploration. On 20 January 2005 the first Russian University Satellite “Universitetskiy-Tatyana” was launched into circular polar orbit (inclination 83 deg., altitude 940-980 km). The onboard scientific complex “Tatyana“, as well as the mission control and information receiving centre, was designed and developed at Moscow State University. The scientific programme of the mission includes measurements of space radiation in different energy channels and Earth UV luminosity and lightning. The current education programme consists of basic multimedia lectures “Life of the Earth in the Solar Atmosphere” and computerized practice exercises “Space Practice” (based on the quasi-real-time data obtained from “Universitetskiy-Tatyana” satellite and other Internet resources). A multimedia lectures LIFE OF EARTH IN THE SOLAR ATMOSPHERE containing the basic information and demonstrations of heliophysics (including Sun structure and solar activity, heliosphere and geophysics, solar-terrestrial connections and solar influence on the Earth’s life) was created for upper high-school and junior university students. For the upper-university students there a dozen special computerized hands-on exercises were created based on the experimental quasi-real-time data obtained from our satellites. Students specializing in space physics from a few Russian universities are involved in scientific work. Educational materials focus on upper high school, middle university and special level for space physics students. Moscow State University is now extending its space science education programme by creating multimedia lectures on remote sensing, space factors and materials study, satellite design and development, etc. The space sciences educational activity of Moscow State University is a non-profit project and is open for all interested parties. “Space schools” for university teachers and students were held in the autumn of 2004 and 2005. The main objective of those schools was to attract interest in space research. Tutors and students who took part in these schools had never before been involved in the space sciences. The idea behind these schools was to join forces: Moscow State University scientists gave space science lectures, students from different universities (Ulianovsk, Samara, Kostroma and other Russian universities) performed the work (prepared educational material) and their university teachers managed the students. After participating in these schools, both students and teachers started to study space science related topics emphasizing the success of these schools. It is important for the educational community to understand what skills future space scientists and space industry employees must be equipped with. In the next years, emphasis is to be placed on space science education at all educational levels and better communication should be practiced between universities and industry.

Solar space and water heating system installed at Charlottesville, Virginia

NASA Technical Reports Server (NTRS)

1980-01-01

The solar energy system located at David C. Wilson Neuropsychiatric Hospital, Charlottesville, Virginia, is described. The solar energy system consists of 88 single glazed, Sunworks 'Solector' copper base plate collector modules, hot water coils in the hot air ducts, a Domestic Hot Water (DHW) preheat tank, a 3,000 gallon concrete urethane insulated storage tank and other miscellaneous components. Extracts from the site files, specifications, drawings, installation, operation and maintenance instructions are included.

A compact Dopplergraph/magnetograph suitable for space-based measurements of solar oscillations and magnetic fields

NASA Technical Reports Server (NTRS)

Rhodes, E. J., Jr.; Cacciani, A.; Tomczyk, S.; Ulrich, R. K.; Blamont, J.; Howard, R. F.; Dumont, P.; Smith, E. J.

1984-01-01

A compact Dopplergraph/magnetograph placed in a continuous solar-viewing orbit will allow us to make major advancements in our understanding of solar internal structure and dynamics. An international program is currently being conducted at JPL and Mt. Wilson to develop such an instrument. By combining a unique magneto-optical resonance filter with CID and CCD cameras we have been able to obtain full- and partial-disk Dopplergrams and magnetograms. Time series of the velocity images are converted into k-omega power spectra which show clear- the solar nonradial p-mode oscilations. Magnetograms suitable for studying the long-term evolution of solar active regions have also been obtained with this instrument. A flight instrument based on this concept is being studied for possible inclusion in the SOHO mission.

Design investigation of solar powered lasers for space applications

NASA Technical Reports Server (NTRS)

Taussig, R.; Bruzzone, C.; Quimby, D.; Nelson, L.; Christiansen, W.; Neice, S.; Cassady, P.; Pindroh, A.

1979-01-01

The feasibility of solar powered lasers for continuous operation in space power transmission was investigated. Laser power transmission in space over distances of 10 to 100 thousand kilometers appears possible. A variety of lasers was considered, including solar-powered GDLs and EDLs, and solar-pumped lasers. An indirect solar-pumped laser was investigated which uses a solar-heated black body cavity to pump the lasant. Efficiencies in the range of 10 to 20 percent are projected for these indirect optically pumped lasers.

Near Earth Asteroid Scout: NASA's Solar Sail Mission to a NEA

NASA Technical Reports Server (NTRS)

Johnson, Les; Castillo-Rogez, Julie; Dervan, Jared

2017-01-01

NASA is developing a solar sail propulsion system for use on the Near Earth Asteroid (NEA) Scout reconnaissance mission and laying the groundwork for their use in future deep space science and exploration missions. Solar sails use sunlight to propel vehicles through space by reflecting solar photons from a large, mirror-like sail made of a lightweight, highly reflective material. This continuous photon pressure provides propellant-less thrust, allowing for very high delta V maneuvers on long-duration, deep space exploration. Since reflected light produces thrust, solar sails require no onboard propellant. The Near Earth Asteroid (NEA) Scout mission, funded by NASA’s Advanced Exploration Systems Program and managed by NASA MSFC, will use the sail as primary propulsion allowing it to survey and image Asteroid 1991VG and, potentially, other NEA’s of interest for possible future human exploration. The NEA Scout spacecraft is housed in a 6U CubeSat-form factor and utilizes an 86 square meter solar sail for a total mass less than 14 kilograms. The mission is in partnership with the Jet Propulsion Laboratory with support from Langley Research Center and science participants from various institutions. NEA Scout will be launched on the maiden flight of the Space Launch System in 2019. The solar sail for NEA Scout will be based on the technology developed and flown by the NASA NanoSail-D and flown on The Planetary Society’s Lightsail-A. Four approximately-7-meter stainless steel booms wrapped on two spools (two overlapping booms per spool) will be motor driven and pull the sail from its stowed volume. The sail material is an aluminized polyimide approximately 2.5 microns thick. As the technology matures, solar sails will increasingly be used to enable science and exploration missions that are currently impossible or prohibitively expensive using traditional chemical and electric propulsion systems. This paper will summarize the status of the NEA Scout mission and solar sail technology in general.

Elliptical varied line-space (EVLS) gratings

NASA Astrophysics Data System (ADS)

Thomas, Roger J.

2004-10-01

Imaging spectroscopy at wavelengths below 2000 Å offers an especially powerful method for studying many extended high-temperature astronomical objects, like the Sun and its outer layers. But the technology to make such measurements is also especially challenging, because of the poor reflectance of all standard materials at these wavelengths, and because the observation must be made from above the absorbing effects of the Earth's atmosphere. To solve these problems, single-reflection stigmatic spectrographs for XUV wavelengths have bee flown on several space missions based on designs with toroidal uniform line-space (TULS) or spherical varied line-space (SVLS) gratings that operate at near normal-incidence. More recently, three solar EUV/UV instruments have been selected that use toroidal varied line-space (TVLS) gratings; these are SUMI and RAISE, both sounding rocket payloads, and NEXUS, a SMEX satellite-mission. The next logical extension to such designs is the use of elliptical surfaces for varied line-space (EVLS) rulings. In fact, EVLS designs are found to provide superior imaging even at very large spectrograph magnifications and beam-speeds, permitting extremely high-quality performance in remarkably compact instrument packages. In some cases, such designs may be optimized even further by using a hyperbolic surface for the feeding telescope. The optical characteristics of two solar EUV spectrometers based on these concepts are described: EUS and EUI, both being developed as possible instruments for ESA's Solar Orbiter mission by consortia led by RAL and by MSSL, respectively.

Ground Based Studies of the Outer Planets

NASA Technical Reports Server (NTRS)

Trafton, Laurence M.

2005-01-01

This report covers progress to date under this grant on our continuing program to conduct ground based studies of the outer solar system planets and satellites, with emphasis on spectroscopy and atmospheric phenomena. The research continues under our new PAST grant, NNG04G131G beginning 5/1/2004. The original period of performance of the subject grant was 3/1/2001 to 2/28/2004, but was extended one year at no cost. Although there is some overlap in the scientific projects conducted during the extended year with those of the new grant, this report is confined to the portion of the work funded under NAG5-10435. The primary goals for this grant period were a comparative study of outer planet thermospheres/ionospheres near solar maximum, extended to the mid-IR, and the investigation of molecular dimers in outer solar system atmospheres. This project supports NASA's planned space missions, Jupiter Polar Orbiter, outer Planet Microprobes, and the recent Cassini flyby of Jupiter. It also supports the OSS strategic plan themes, The Exploration of the Solar System and The Sun-Earth Connection/ Understanding comparative planetary space environments.

The Visibility of Earth Transits

NASA Technical Reports Server (NTRS)

Castellano, Tim; DeVincenzi, Donald L. (Technical Monitor)

2000-01-01

The recent detection of planetary transits of the solar-like star HD 209458 at a distance of 47 parsecs suggest that transits can reveal the presence of Jupiter-size planetary companions in the solar neighborhood. Recent space-based transit searches have achieved photometric precision within an order of magnitude of that required to detect the much smaller transit signal of an earth-size planet around a solar-size star. Laboratory experiments in the presence of realistic noise sources have shown that CCDs can achieve photometric precision adequate to detect the 9.6 E-5 dimming, of the Sun due to a transit of the Earth. Space-based solar irradiance monitoring has shown that the intrinsic variability of the Sun would not preclude such a detection. Transits of the Sun by the Earth would be detectable by observers that reside within a narrow band of sky positions near the ecliptic plane, if the observers possess current Earth epoch levels of technology and astronomical expertise. A catalog of candidate target stars, their properties, and simulations of the photometric Earth transit signal detectability at each target is presented.

MILSTAR's flexible substrate solar array: Lessons learned, addendum

NASA Technical Reports Server (NTRS)

Gibb, John

1990-01-01

MILSTAR's Flexible Substrate Solar Array (FSSA) is an evolutionary development of the lightweight, flexible substrate design pioneered at Lockheed during the seventies. Many of the features of the design are related to the Solar Array Flight Experiment (SAFE), flown on STS-41D in 1984. FSSA development has created a substantial technology base for future flexible substrate solar arrays such as the array for the Space Station Freedom. Lessons learned during the development of the FSSA can and should be applied to the Freedom array and other future flexible substrate designs.

Fresnel Concentrators for Space Solar Power and Solar Thermal Propulsion

NASA Technical Reports Server (NTRS)

Bradford, Rodney; Parks, Robert W.; Craig, Harry B. (Technical Monitor)

2001-01-01

Large deployable Fresnel concentrators are applicable to solar thermal propulsion and multiple space solar power generation concepts. These concentrators can be used with thermophotovoltaic, solar thermionic, and solar dynamic conversion systems. Thin polyimide Fresnel lenses and reflectors can provide tailored flux distribution and concentration ratios matched to receiver requirements. Thin, preformed polyimide film structure components assembled into support structures for Fresnel concentrators provide the capability to produce large inflation-deployed concentrator assemblies. The polyimide film is resistant to the space environment and allows large lightweight assemblies to be fabricated that can be compactly stowed for launch. This work addressed design and fabrication of lightweight polyimide film Fresnel concentrators, alternate materials evaluation, and data management functions for space solar power concepts, architectures, and supporting technology development.

Societal Impacts of Solar Electromagnetic Radiation

NASA Astrophysics Data System (ADS)

Lean, J. L.

2000-05-01

Changes in solar electromagnetic radiation, which occur continuously and at all wavelengths of the spectrum, can have significant societal impacts on a wide range of time scales. Detection of climate change and ozone depletion requires reliable specification of solar-induced processes that mask or exacerbate anthropogenic effects. Living with, and mitigating, climate change and ozone depletion has significant economic, habitat and political impacts of international extent. As an example, taxes to restrict carbon emission may cause undue economic stress if the role of greenhouse gases in global warming is incorrectly diagnosed. Ignoring solar-induced ozone changes in the next century may lead to incorrect assessment of the success of the Montreal Protocol in protecting the ozone layer by limiting the use of ozone-destroying chlorofluorocarbons. Societal infrastructure depends in many ways on space-based technological assets. Communications and navigation for commerce, industry, science and defense rely on satellite signals transmitted through, and reflected by, electrons in the ionosphere. Electron densities change in response to solar flares, and by orders of magnitude in response to EUV and X-ray flux variations during the Sun's 11-year activity cycle. Spacecraft and space debris experience enhanced drag on their orbits when changing EUV radiation causes upper atmosphere densities to increase. Especially affected are spacecraft and debris in lower altitude orbits, such as Iridium-type communication satellites, and the International Space Station (ISS). Proper specification of solar-induced fluctuations in the neutral upper atmosphere can, for example, aid in tracking the ISS and surrounding space debris, reducing the chance of ISS damage from collisions, and maximizing its operations. Aspects of solar electromagnetic radiation variability will be briefly illustrated on a range of time scales, with specific identification of the societal impacts of different spectral regions.

Application of Semi Active Control Techniques to the Damping Suppression Problem of Solar Sail Booms

NASA Technical Reports Server (NTRS)

Adetona, O.; Keel, L. H.; Whorton, M. S.

2007-01-01

Solar sails provide a propellant free form for space propulsion. These are large flat surfaces that generate thrust when they are impacted by light. When attached to a space vehicle, the thrust generated can propel the space vehicle to great distances at significant speeds. For optimal performance the sail must be kept from excessive vibration. Active control techniques can provide the best performance. However, they require an external power-source that may create significant parasitic mass to the solar sail. However, solar sails require low mass for optimal performance. Secondly, active control techniques typically require a good system model to ensure stability and performance. However, the accuracy of solar sail models validated on earth for a space environment is questionable. An alternative approach is passive vibration techniques. These do not require an external power supply, and do not destabilize the system. A third alternative is referred to as semi-active control. This approach tries to get the best of both active and passive control, while avoiding their pitfalls. In semi-active control, an active control law is designed for the system, and passive control techniques are used to implement it. As a result, no external power supply is needed so the system is not destabilize-able. Though it typically underperforms active control techniques, it has been shown to out-perform passive control approaches and can be unobtrusively installed on a solar sail boom. Motivated by this, the objective of this research is to study the suitability of a Piezoelectric (PZT) patch actuator/sensor based semi-active control system for the vibration suppression problem of solar sail booms. Accordingly, we develop a suitable mathematical and computer model for such studies and demonstrate the capabilities of the proposed approach with computer simulations.

A generalized analysis of solar space heating

NASA Astrophysics Data System (ADS)

Clark, J. A.

A life-cycle model is developed for solar space heating within the United States. The model consists of an analytical relationship among five dimensionless parameters that include all pertinent technical, climatological, solar, operating and economic factors that influence the performance of a solar space heating system. An important optimum condition presented is the break-even metered cost of conventional fuel at which the cost of the solar system is equal to that of a conventional heating system. The effect of Federal (1980) and State (1979) income tax credits on these costs is determined. A parameter that includes both solar availability and solar system utilization is derived and plotted on a map of the U.S. This parameter shows the most favorable present locations for solar space heating application to be in the Central and Mountain States. The data employed are related to the rehabilitated solar data recently made available by the National Climatic Center.

Space Plasma Shown to Make Satellite Solar Arrays Fail

NASA Technical Reports Server (NTRS)

Ferguson, Dale C.

1999-01-01

In 1997, scientists and engineers of the Photovoltaic and Space Environments Branch of the NASA Lewis Research Center, Maxwell Technologies, and Space Systems/Loral discovered a new failure mechanism for solar arrays on communications satellites in orbit. Sustained electrical arcs, initiated by the space plasma and powered by the solar arrays themselves, were found to have destroyed solar array substrates on some Space Systems/Loral satellites, leading to array failure. The mechanism was tested at Lewis, and mitigation strategies were developed to prevent such disastrous occurrences on-orbit in the future. Deep Space 1 is a solar-electric-powered space mission to a comet, launched on October 24, 1998. Early in 1998, scientists at Lewis and Ballistic Missile Defense Organization (BMDO) realized that some aspects of the Deep Space 1 solar arrays were nearly identical to those that had led to the failure of solar arrays on Space Systems/Loral satellites. They decided to modify the Deep Space 1 arrays to prevent catastrophic failure in space. The arrays were suitably modified and are now performing optimally in outer space. Finally, the Earth Observing System (EOS) AM1, scheduled for launch in mid-1999, is a NASA mission managed by the Goddard Space Flight Center. Realizing the importance of Lewis testing on the Loral arrays, EOS-AM1 management asked Lewis scientists to test their solar arrays to show that they would not fail in the same way. The first phase of plasma testing showed that sustained arcing would occur on the unmodified EOS-AM1 arrays, so the arrays were removed from the spacecraft and fixed. Now, Lewis scientists have finished plasma testing of the modified array configuration to ensure that EOS-AM1 will have no sustained arcing problems on-orbit.

International Lunar Decade Status

NASA Astrophysics Data System (ADS)

Beldavs, VZ; Crisafulli, J.; Dunlop, D.; Foing, B.

2017-09-01

The International Lunar Decade is a global decadal event designed to provide a framework for strategically directed international cooperation for permanent return to the Moon. To be launched July 20, 2019, the 50th anniversary of the giant leap for mankind marked by Neil Armstrong's first step on the Moon, the ILD launch will include events around the world to celebrate space exploration, science, and the expansion of humanity into the Solar System. The ILD framework links lunar exploration and space sciences with the development of enabling technologies, infrastructure, means of financing, laws and policies aimed at lowering the costs and risks of venturing into space. Dramatically reduced costs will broaden the range of opportunities available in space and widen access to space for more states, companies and people worldwide. The ILD is intended to bring about the efflorescence of commercial business based on space resources from the Moon, asteroids, comets and other bodies in the Solar System.

Research and technology, fiscal year 1982

NASA Technical Reports Server (NTRS)

1982-01-01

Advanced studies are reviewed. Atmospheric sciences, magnetospheric physics, solar physics, gravitational physics, astronomy, and materials processing in space comprise the research programs. Large space systems, propulsion technology, materials and processes, electrical/electronic systems, data bases/design criteria, and facilities development comprise the technology development activities.

Systems efficiency and specific mass estimates for direct and indirect solar-pumped closed-cycle high-energy lasers in space

NASA Technical Reports Server (NTRS)

Monson, D. J.

1978-01-01

Based on expected advances in technology, the maximum system efficiency and minimum specific mass have been calculated for closed-cycle CO and CO2 electric-discharge lasers (EDL's) and a direct solar-pumped laser in space. The efficiency calculations take into account losses from excitation gas heating, ducting frictional and turning losses, and the compressor efficiency. The mass calculations include the power source, radiator, compressor, fluids, ducting, laser channel, optics, and heat exchanger for all of the systems; and in addition the power conditioner for the EDL's and a focusing mirror for the solar-pumped laser. The results show the major component masses in each system, show which is the lightest system, and provide the necessary criteria for solar-pumped lasers to be lighter than the EDL's. Finally, the masses are compared with results from other studies for a closed-cycle CO2 gasdynamic laser (GDL) and the proposed microwave satellite solar power station (SSPS).

KSC-08pd1685

NASA Image and Video Library

2008-04-30

VANDENBERG AIR FORCE BASE, Calif. – In Building 1555, workers check the movement of the wing toward the Pegasus XL launch vehicle. The Pegasus will launch NASA's Interstellar Boundary Explorer Mission, or IBEX, satellite from Kwajalein Island in the Marshall Islands, South Pacific. IBEX will make the first map of the boundary between the solar system and interstellar space. IBEX is the first mission designed to detect the edge of the solar system. As the solar wind from the sun flows out beyond Pluto, it collides with the material between the stars, forming a shock front. IBEX contains two neutral atom imagers designed to detect particles from the termination shock at the boundary between the solar system and interstellar space. IBEX also will study galactic cosmic rays, energetic particles from beyond the solar system that pose a health and safety hazard for humans exploring beyond Earth orbit. IBEX will make these observations from a highly elliptical orbit that takes it beyond the interference of the Earth's magnetosphere. Photo credit: NASA/Randy Beaudoin

UNISAT-3 Power System

NASA Astrophysics Data System (ADS)

Santoni, Fabio; Piergentili, Fabrizio; Bulgarelli, Fabio; Graziani, Filippo

2005-05-01

An overview of the UNISAT-3 microsatellite power subsystem is given. This is an educational, low weight and low cost microsatellite designed, built, launched and operated in space by students and professors of Scuola di Ingegneria Aerospaziale, at University of Rome "La Sapienza". The satellite power system is based on terrestrial technology solar arrays and NiCd batteries. The microsatellite hosts other solar arrays, including multi-junction solar cells and mono- crystalline silicon high efficiency solar cells, in order to compare their behaviour in orbit. Moreover a MPPT (Maximum Power Point Tracking ) system has been designed and tested, and it is a technological payload of UNISAT-3. The MPPT design follows the studies performed in the field of solar powered racing cars, with modifications to make the system suitable for use in space. The system design, numerical simulation and hardware ground testing are described in the paper. The experiment and the performance evaluation criterion are described, together with the preliminary results of the first eight months of operation in orbit.

KSC-08pd1682

NASA Image and Video Library

2008-04-30

VANDENBERG AIR FORCE BASE, Calif. – In Building 1555, workers help guide a wing toward the Pegasus XL launch vehicle for a fit check. The Pegasus will launch NASA's Interstellar Boundary Explorer Mission, or IBEX, satellite from Kwajalein Island in the Marshall Islands, South Pacific. IBEX will make the first map of the boundary between the solar system and interstellar space. IBEX is the first mission designed to detect the edge of the solar system. As the solar wind from the sun flows out beyond Pluto, it collides with the material between the stars, forming a shock front. IBEX contains two neutral atom imagers designed to detect particles from the termination shock at the boundary between the solar system and interstellar space. IBEX also will study galactic cosmic rays, energetic particles from beyond the solar system that pose a health and safety hazard for humans exploring beyond Earth orbit. IBEX will make these observations from a highly elliptical orbit that takes it beyond the interference of the Earth's magnetosphere. Photo credit: NASA/Randy Beaudoin

KSC-08pd1677

NASA Image and Video Library

2008-04-28

VANDENBERG AIR FORCE BASE, Calif. – In Building 1555, the wings of the Pegasus XL launch vehicle are checked for fit. The Pegasus will launch NASA's Interstellar Boundary Explorer Mission, or IBEX, satellite from Kwajalein Island in the Marshall Islands, South Pacific. IBEX will make the first map of the boundary between the solar system and interstellar space. IBEX is the first mission designed to detect the edge of the solar system. As the solar wind from the sun flows out beyond Pluto, it collides with the material between the stars, forming a shock front. IBEX contains two neutral atom imagers designed to detect particles from the termination shock at the boundary between the solar system and interstellar space. IBEX also will study galactic cosmic rays, energetic particles from beyond the solar system that pose a health and safety hazard for humans exploring beyond Earth orbit. IBEX will make these observations from a highly elliptical orbit that takes it beyond the interference of the Earth's magnetosphere. Photo credit: NASA/Randy Beaudoin

KSC-08pd1686

NASA Image and Video Library

2008-04-30

VANDENBERG AIR FORCE BASE, Calif. – In Building 1555, workers check the fit of the wing on the Pegasus XL launch vehicle. The Pegasus will launch NASA's Interstellar Boundary Explorer Mission, or IBEX, satellite from Kwajalein Island in the Marshall Islands, South Pacific. IBEX will make the first map of the boundary between the solar system and interstellar space. IBEX is the first mission designed to detect the edge of the solar system. As the solar wind from the sun flows out beyond Pluto, it collides with the material between the stars, forming a shock front. IBEX contains two neutral atom imagers designed to detect particles from the termination shock at the boundary between the solar system and interstellar space. IBEX also will study galactic cosmic rays, energetic particles from beyond the solar system that pose a health and safety hazard for humans exploring beyond Earth orbit. IBEX will make these observations from a highly elliptical orbit that takes it beyond the interference of the Earth's magnetosphere. Photo credit: NASA/Randy Beaudoin

KSC-08pd1683

NASA Image and Video Library

2008-04-30

VANDENBERG AIR FORCE BASE, Calif. – In Building 1555, workers help guide a wing toward the Pegasus XL launch vehicle in the background for a fit check. The Pegasus will launch NASA's Interstellar Boundary Explorer Mission, or IBEX, satellite from Kwajalein Island in the Marshall Islands, South Pacific. IBEX will make the first map of the boundary between the solar system and interstellar space. IBEX is the first mission designed to detect the edge of the solar system. As the solar wind from the sun flows out beyond Pluto, it collides with the material between the stars, forming a shock front. IBEX contains two neutral atom imagers designed to detect particles from the termination shock at the boundary between the solar system and interstellar space. IBEX also will study galactic cosmic rays, energetic particles from beyond the solar system that pose a health and safety hazard for humans exploring beyond Earth orbit. IBEX will make these observations from a highly elliptical orbit that takes it beyond the interference of the Earth's magnetosphere. Photo credit: NASA/Randy Beaudoin

KSC-08pd1676

NASA Image and Video Library

2008-04-28

VANDENBERG AIR FORCE BASE, Calif. – In Building 1555, the wings of the Pegasus XL launch vehicle are checked for fit. The Pegasus will launch NASA's Interstellar Boundary Explorer Mission, or IBEX, satellite from Kwajalein Island in the Marshall Islands, South Pacific. IBEX will make the first map of the boundary between the solar system and interstellar space. IBEX is the first mission designed to detect the edge of the solar system. As the solar wind from the sun flows out beyond Pluto, it collides with the material between the stars, forming a shock front. IBEX contains two neutral atom imagers designed to detect particles from the termination shock at the boundary between the solar system and interstellar space. IBEX also will study galactic cosmic rays, energetic particles from beyond the solar system that pose a health and safety hazard for humans exploring beyond Earth orbit. IBEX will make these observations from a highly elliptical orbit that takes it beyond the interference of the Earth's magnetosphere. Photo credit: NASA/Randy Beaudoin

KSC-08pd1684

NASA Image and Video Library

2008-04-30

VANDENBERG AIR FORCE BASE, Calif. – In Building 1555, workers help guide a wing toward the Pegasus XL launch vehicle in the background for a fit check. The Pegasus will launch NASA's Interstellar Boundary Explorer Mission, or IBEX, satellite from Kwajalein Island in the Marshall Islands, South Pacific. IBEX will make the first map of the boundary between the solar system and interstellar space. IBEX is the first mission designed to detect the edge of the solar system. As the solar wind from the sun flows out beyond Pluto, it collides with the material between the stars, forming a shock front. IBEX contains two neutral atom imagers designed to detect particles from the termination shock at the boundary between the solar system and interstellar space. IBEX also will study galactic cosmic rays, energetic particles from beyond the solar system that pose a health and safety hazard for humans exploring beyond Earth orbit. IBEX will make these observations from a highly elliptical orbit that takes it beyond the interference of the Earth's magnetosphere. Photo credit: NASA/Randy Beaudoin

SEPEM: A tool for statistical modeling the solar energetic particle environment

NASA Astrophysics Data System (ADS)

Crosby, Norma; Heynderickx, Daniel; Jiggens, Piers; Aran, Angels; Sanahuja, Blai; Truscott, Pete; Lei, Fan; Jacobs, Carla; Poedts, Stefaan; Gabriel, Stephen; Sandberg, Ingmar; Glover, Alexi; Hilgers, Alain

2015-07-01

Solar energetic particle (SEP) events are a serious radiation hazard for spacecraft as well as a severe health risk to humans traveling in space. Indeed, accurate modeling of the SEP environment constitutes a priority requirement for astrophysics and solar system missions and for human exploration in space. The European Space Agency's Solar Energetic Particle Environment Modelling (SEPEM) application server is a World Wide Web interface to a complete set of cross-calibrated data ranging from 1973 to 2013 as well as new SEP engineering models and tools. Both statistical and physical modeling techniques have been included, in order to cover the environment not only at 1 AU but also in the inner heliosphere ranging from 0.2 AU to 1.6 AU using a newly developed physics-based shock-and-particle model to simulate particle flux profiles of gradual SEP events. With SEPEM, SEP peak flux and integrated fluence statistics can be studied, as well as durations of high SEP flux periods. Furthermore, effects tools are also included to allow calculation of single event upset rate and radiation doses for a variety of engineering scenarios.

Challenges in Heliophysics and Space Weather: What Instrumentation for the Future?

NASA Astrophysics Data System (ADS)

Guhathakurta, Madhulika

A hundred years ago, the sun-Earth connection (the field of heliophysics research and space weather impacts) was of interest to only a small number of scientists. Solar activity had little effect on daily life. Today, a single strong solar flare could bring civilization to its knees. Modern society has come to depend on technologies sensitive to solar radiation and geomagnetic storms. Particularly vulnerable are intercontinental power grids, interplanetary robotic and human exploration, satellite operations and communications, and GPS navigation. These technologies are woven into the fabric of daily life, from health care and finance to basic utilities. Both short- and long-term forecasting models are urgently needed to mitigate the effects of solar storms and to anticipate their collective impact on aviation, astronaut safety, terrestrial climate and others. Even during a relatively weak solar maximum, the potential consequences that such events can have on society are too important to ignore. The challenges associated with space weather affect all developed and developing countries. Work on space weather specification, modeling, and forecasting has great societal benefit: It is basic research with a high public purpose. At present, we have a fleet “Heliophysics System Observatory” of dedicated spacecraft titled (e.g. SOHO, STEREO, SDO, ACE), and serendipitous resources contributing data for space weather modeling from both remote observations of the sun and in-situ measurements to provide sparse space weather situational awareness which were mostly built for a 2-3 year lifetime and are wearing out and won’t be around for very long. Missions currently in formulation will significantly enhance the capability of physics-based models that are used to understand and predict the impact of the variable sun. To enhance current models, and make them effective in predicting space weather throughout the solar system, we need a distributed network of spacecraft collecting relevant data that can be assimilated into models. In this talk I will discuss several additional approaches that could be used for the necessary augmentation of the existing HSO capabilities and replacement of aging HSO instruments, enabling interplanetary space weather and climate predictions.

CLARREO Pathfinder Mission to ISS: Demonstrating Greatly Increased Accuracy for Reflected Solar Space Based Observations: Calibration and Intercalibration

NASA Astrophysics Data System (ADS)

Wielicki, B. A.

2016-12-01

The CLARREO (Climate Absolute Radiance and Refractivity) Pathfinder mission is a new mission started by NASA in 2016. CLARREO Pathfinder will fly a new generation of high accuracy reflected solar spectrometer in orbit on the Inernational Space Station (ISS) to demonstrate the ability to increase accuracy of reflected solar observations from space by a factor of 3 to 20. The spectrometer will use the sun and moon as calibration sources with a baseline objective of 0.3% (1 sigma) reflectance calibration uncertainty for the contiguous spectrum from 350nm to 2300nm, covering over 95% of the Earth's reflected solar spectrum. Spectral sampling is 3nm with resolution of 6nm. The spectrometer is mounted on a 2-axis gimbal enabling a new ability to use the same optical path to view the sun, moon, and Earth. Planned launch is 2020 with at least 1 year on orbit to demonstrate the new capability. The mission will also demonstrate the ability to use the new spectrometer as a reference transfer spectrometer in orbit to achieve intercalibration of reflected solar instruments to within 0.3% (1 sigma) using space, time, spectral, and angle matched observations across the full scan width of remote sensing instruments. Intercalibration to 0.3% will be demonstrated across the full scan width of the NASA CERES broadband radiometer and the NOAA VIIRS imager reflected solar spectral channels. This mission will demonstrate reflected solar intercalibration across the full swath width as opposed to current nadir only intercalibration used by GSICS (Global Space Based InterCalibration System). Intercalibration will include a new capability to determine scan angle dependence of polarization sensitivity of instruments like VIIRS. The high accuracy goals of this mission are driven primarily by the accuracy required to more rapidly and accurately observe climate change signals such as cloud feedback (see Wielicki et al. 2013 Bulletin of the American Meteorological Society). The new high accuracy and intercalibration capability will also be very useful for serving as a reference calibrator for constellations of operational instruments in Geostationary or Low Earth Orbit (e.g. land resource imagers, ocean color, cloud imagers). The higher accuracy will enable operational sensors to more effectively serve as climate change sensors.

Development of composite facets for the surface of a space-based solar dynamic concentrator

NASA Technical Reports Server (NTRS)

Ayers, Schuyler R.; Morel, Donald E.; Sanborn, James A.

1986-01-01

An account is given of the composite fabrication techniques envisioned for the production of mirror-quality substrates furnishing the specular reflectance required for the NASA Space Station's solar dynamic concentrator energy system. The candidate materials were graphite fiber-reinforced glass, aluminum, and polymer matrices whose surfaces would be coated with thin metal layers and with atomic oxygen degradation-inhibiting protective coatings to obtain the desired mirror surface. Graphite-epoxy mirror substrate samples have been found to perform satisfactorily for the required concentrator lifetime.

The Role of Structural Models in the Solar Sail Flight Validation Process

NASA Technical Reports Server (NTRS)

Johnston, John D.

2004-01-01

NASA is currently soliciting proposals via the New Millennium Program ST-9 opportunity for a potential Solar Sail Flight Validation (SSFV) experiment to develop and operate in space a deployable solar sail that can be steered and provides measurable acceleration. The approach planned for this experiment is to test and validate models and processes for solar sail design, fabrication, deployment, and flight. These models and processes would then be used to design, fabricate, and operate scaleable solar sails for future space science missions. There are six validation objectives planned for the ST9 SSFV experiment: 1) Validate solar sail design tools and fabrication methods; 2) Validate controlled deployment; 3) Validate in space structural characteristics (focus of poster); 4) Validate solar sail attitude control; 5) Validate solar sail thrust performance; 6) Characterize the sail's electromagnetic interaction with the space environment. This poster presents a top-level assessment of the role of structural models in the validation process for in-space structural characteristics.

COMESEP: bridging the gap between the SEP, CME, and terrestrial effects scientific communities

NASA Astrophysics Data System (ADS)

Crosby, Norma; Veronig, Astrid; Rodriguez, Luciano; Vrsnak, Bojan; Vennerstrøm, Susanne; Malandraki, Olga; Dalla, Silvia; Srivastava, Nandita

2016-04-01

In the past there has been a tendency for the geomagnetic storm and solar energetic particle (SEP) communities to work in parallel rather than to apply a cross-disciplinary work approach specifically in regard to space weather forecasting. To provide more awareness on the existing links between these communities, as well as further bridge this gap, the three-year EU FP7 COMESEP (COronal Mass Ejections and Solar Energetic Particles: forecasting the space weather impact) project emphasized cross-collaboration between the SEP, coronal mass ejection, and terrestrial effects scientific communities. COMESEP went from basic solar-terrestrial physics research to space weather operations by developing, validating and implementing multi-purpose tools into an operational 24/7 alert service. Launched in November 2013, the COMESEP alert system provides space weather stakeholders geomagnetic storm alerts ("Event based" and "Next 24 hours") and SEP (proton) storm alerts (E > 10 MeV and E > 60 MeV) without human intervention based on the COMESEP definition of risk. COMESEP alerts and forecasts are freely available on the COMESEP alert website (http://www.comesep.eu/alert), as well as disseminated by e-mail to registered users. Acknowledgement: This work has received funding from the European Commission FP7 Project COMESEP (263252).

Wireless Power Transmission Options for Space Solar Power

NASA Technical Reports Server (NTRS)

Henley, M. W.; Potter, Seth D.; Howell, J.; Mankins, J. C.; Fikes, John C. (Technical Monitor)

2002-01-01

Space Solar Power (SSP). combined with Wireless Power Transmission (WPT), offers the far-term potential to solve major energy problems on Earth. In this paper WPT options using radio waves and light waves are considered for both long-term and near-term SSP applications. In the long-term, we aspire to beam energy to Earth from geostationary Earth orbit (GEO), or even from the moon. Accordingly, radio- and light- wave WPT options are compared through a wide range of criteria, each showing certain strengths. In the near-term. we plan to beam power over more moderate distances, but still stretch the limits of today's technology. For the near-term, a 100 kWe-class 'Power Plug' Satellite and a 10 kWe-class Lunar Polar Solar Power outpost are considered as the first steps in using these WPT options for SSP. By using SSP and WPT technology in near-term space science and exploration missions, we gain experience needed for sound decisions in designing and developing larger systems to send power from Space to Earth. Power Relay Satellites are also considered as a potential near- to mid-term means to transmit power from Earth to Space and back to distant receiving sites on Earth. This paper briefly considers microwave and laser beaming for an initial Power Relay Satellite system, and concludes that anticipated advancements in laser technology make laser-based concepts more attractive than microwave-based concepts. Social and economic considerations are briefly discussed, and a conceptual description for a laser-based system is offered for illustrative purposes. Continuing technological advances are needed if laser-based systems are to become practical and efficient or near- and far-term applications.

The Moon: Resources, Future Development and Colonization

NASA Astrophysics Data System (ADS)

Schrunk, David; Sharpe, Burton; Cooper, Bonnie; Thangavelu, Madhu

1999-07-01

This unique, visionary and innovative book describes how the Moon could be colonised and developed as a platform for science, industrialization and exploration of our Solar System and beyond. Thirty years ago, the world waited with baited breath to watch history in the making, as man finally stepped onto the moon's surface. In the last few years, there has been growing interest in the idea of a return to the moon. This book describes the reasons why we should now start lunar development and settlement, and how this goal may be accomplished. The authors, all of whom are hugely experienced space scientists, consider the rationale and steps necessary for establishing permanent bases on the Moon. Their innovative and scientific-based analysis concludes that the Moon has sufficient resources for large-scale human development. Their case for development includes arguments for a solar-powered electric grid and railroad, creation of a utilities infrastructure, habitable facilities, scientific operations and the involvement of private enterprise with the public sector in the macroproject. By transferring and adapting existing technologies to the lunar environment, the authors argue that it will be possible to use lunar resources and solar power to build a global lunar infrastructure embracing power, communication, transportation, and manufacturing. This will support the migration of increasing numbers of people from Earth, and realization of the Moon's scientific potential. As an inhabited world, the Moon is an ideal site for scientific laboratories dedicated to geosciences, astronomy and life sciences, and most importantly, it would fulfil a role as a proving ground and launch pad for future Solar System exploration. The ten chapters in this book go beyond the theoretical and conceptual. With vision and foresight, the authors offer practical means for establishing permanent bases on the Moon. The book will make fascinating and stimulating reading for students in astronautics, space science, life sciences, space engineering and technology as well as professional space scientists, engineers and technologists in space projects.

A temporal forecast of radiation environments for future space exploration missions.

PubMed

Kim, Myung-Hee Y; Cucinotta, Francis A; Wilson, John W

2007-06-01

The understanding of future space radiation environments is an important goal for space mission operations, design, and risk assessment. We have developed a solar cycle statistical model in which sunspot number is coupled to space-related quantities, such as the galactic cosmic radiation (GCR) deceleration potential (phi) and the mean occurrence frequency of solar particle events (SPEs). Future GCR fluxes were derived from a predictive model, in which the temporal dependence represented by phi was derived from GCR flux and ground-based Climax neutron monitor rate measurements over the last four decades. These results showed that the point dose equivalent inside a typical spacecraft in interplanetary space was influenced by solar modulation by up to a factor of three. It also has been shown that a strong relationship exists between large SPE occurrences and phi. For future space exploration missions, cumulative probabilities of SPEs at various integral fluence levels during short-period missions were defined using a database of proton fluences of past SPEs. Analytic energy spectra of SPEs at different ranks of the integral fluences for energies greater than 30 MeV were constructed over broad energy ranges extending out to GeV for the analysis of representative exposure levels at those fluences. Results will guide the design of protection systems for astronauts during future space exploration missions.

A simple method for predicting solar fractions of IPH and space heating systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chauhan, R.; Goodling, J.S.

1982-01-01

In this paper, a method has been developed to evaluate the solar fractions of liquid based industrial process heat (IPH) and space heating systems, without the use of computer simulations. The new method is the result of joining two theories, Lunde's equation to determine monthly performance of solar heating systems and the utilizability correlations of Collares-Pereira and Rabl by making appropriate assumptions. The new method requires the input of the monthly averages of the utilizable radiation and the collector operating time. These quantities are determined conveniently by the method of Collares-Pereira and Rabl. A comparison of the results of themore » new method with the most acceptable design methods shows excellent agreement.« less

Solar Electric Propulsion for Mars Exploration

NASA Technical Reports Server (NTRS)

Hack, Kurt J.

1998-01-01

Highly propellant-efficient electric propulsion is being combined with advanced solar power technology to provide a non-nuclear transportation option for the human exploration of Mars. By virtue of its high specific impulse, electric propulsion offers a greater change in spacecraft velocity for each pound of propellant than do conventional chemical rockets. As a result, a mission to Mars based on solar electric propulsion (SEP) would require fewer heavy-lift launches than a traditional all-chemical space propulsion scenario would. Performance, as measured by mass to orbit and trip time, would be comparable to the NASA design reference mission for human Mars exploration, which utilizes nuclear thermal propulsion; but it would avoid the issues surrounding the use of nuclear reactors in space.

Space-based solar power conversion and delivery systems study. Volume 4: Energy conversion systems studies

NASA Technical Reports Server (NTRS)

1977-01-01

Solar cells and optical configurations for the SSPS were examined. In this task, three specific solar cell materials were examined: single crystal silicon, single crystal gallium arsenide, and polycrystalline cadmium sulfide. The comparison of the three different cells on the basis of a subsystem parametric cost per kW of SSPS-generated power at the terrestrial utility interface showed that gallium arsenide was the most promising solar cell material at high concentration ratios. The most promising solar cell material with no concentration, was dependent upon the particular combination of parameters representing cost, mass and performance that were chosen to represent each cell in this deterministic comparative analysis. The potential for mass production, based on the projections of the present state-of-the-art would tend to favor cadmium sulfide in lieu of single crystal silicon or gallium arsenide solar cells.

Plasma Interaction with International Space Station High Voltage Solar Arrays

NASA Technical Reports Server (NTRS)

Heard, John W.

2002-01-01

The International Space Station (ISS) is presently being assembled in low-earth orbit (LEO) operating high voltage solar arrays (-160 V max, -140 V typical with respect to the ambient atmosphere). At the station's present altitude, there exists substantial ambient plasma that can interact with the solar arrays. The biasing of an object to an electric potential immersed in plasma creates a plasma "sheath" or non-equilibrium plasma around the object to mask out the electric fields. A positively biased object can collect electrons from the plasma sheath and the sheath will draw a current from the surrounding plasma. This parasitic current can enter the solar cells and effectively "short out" the potential across the cells, reducing the power that can be generated by the panels. Predictions of collected current based on previous high voltage experiments (SAMPIE (Solar Array Module Plasma Interactions Experiment), PASP+ (Photovoltaic Array Space Power) were on the order of amperes of current. However, present measurements of parasitic current are on the order of several milliamperes, and the current collection mainly occurs during an "eclipse exit" event, i.e., when the space station comes out of darkness. This collection also has a time scale, t approx. 1000 s, that is much slower than any known plasma interaction time scales. The reason for the discrepancy between predictions and present electron collection is not understood and is under investigation by the PCU (Plasma Contactor Unit) "Tiger" team. This paper will examine the potential structure within and around the solar arrays, and the possible causes and reasons for the electron collection of the array.

Directly solar-pumped iodine laser for beamed power transmission in space

NASA Technical Reports Server (NTRS)

Choi, S. H.; Meador, W. E.; Lee, J. H.

1992-01-01

A new approach for development of a 50-kW directly solar-pumped iodine laser (DSPIL) system as a space-based power station was made using a confocal unstable resonator (CUR). The CUR-based DSPIL has advantages, such as performance enhancement, reduction of total mass, and simplicity which alleviates the complexities inherent in the previous system, master oscillator/power amplifier (MOPA) configurations. In this design, a single CUR-based DSPIL with 50-kW output power was defined and compared to the MOPA-based DSPIL. Integration of multiple modules for power requirements more than 50-kW is physically and structurally a sound approach as compared to building a single large system. An integrated system of multiple modules can respond to various mission power requirements by combining and aiming the coherent beams at the user's receiver.

Microphysics of Waves and Instabilities in the Solar Wind and Their Macro Manifestations in the Corona and Interplanetary Space

NASA Technical Reports Server (NTRS)

Habbal, Shadia Rifai

2005-01-01

Investigations of the physical processes responsible for coronal heating and the acceleration of the solar wind were pursued with the use of our recently developed 2D MHD solar wind code and our 1D multifluid code. In particular, we explored: (1) the role of proton temperature anisotropy in the expansion of the solar (2) the role of plasma parameters at the coronal base in the formation of high (3) a three-fluid model of the slow solar wind (4) the heating of coronal loops (5) a newly developed hybrid code for the study of ion cyclotron resonance in wind, speed solar wind streams at mid-latitudes, the solar wind.

Lunar Solar Power System Driven Human Development of the Moon and Resource-Rich Exploration of the Inner Solar System

NASA Astrophysics Data System (ADS)

Criswell, D. R.

2002-01-01

The people of Earth require, by the middle of the 21st century, a new source of commercial power that is sustainable, clean, reliable, low in cost (< 1 cent per kilowatt electric hour), not disruptive of the biosphere, and at least 4 to 5 times more abundant (> 2 kWe/person or > 20 TWe) than now (1, 2). The Lunar Solar Power (LSP) System appears to be the only reasonable option (2, 3). The Moon dependably receives 13,000 TWs of solar power. The LSP System consists of pairs of power bases located on opposite limbs of the Moon as seen from Earth. The power bases collect the solar energy and convert it to beams of microwaves. The microwaves are delivered directly to moonward-facing receivers on Earth or indirectly through relay satellites in orbit about Earth. To achieve low cost, the power bases are made primarily of local lunar materials by machines, facilities, and people deployed from Earth. Hundreds to thousands of people will be required on the Moon, in cis-lunar space, and operating tele-robotically from Earth to construct the full scale LSP System. Models indicate that power sales on Earth can easily support the required people, their regular transport between the Earth and Moon, and provide the required return on investment to develop the LSP System (4, 5). Construction of the LSP System, even at an early stage, creates fundamentally new wealth and capabilities supportive of rapid growth of human activities within the inner solar system. A factor of ten increase in global Earth-to-orbit transport will be required in the demonstration phase. Launch cost of 5,000 /kg is acceptable. Lower cost transport decreases the upfront cost of the LSP System but is not critical to the cost of energy from the mature LSP. Logistic and assembly facilities in orbit about the Earth and Moon will be required that are at least a factor of ten large than planned for the full scale International Space Station. Transport must be provided between the Earth and the Moon of hundreds, possibly thousands, of workers. Production machinery will be available that can build fundamentally new infrastructure from the common silicate materials of asteroids and the moons of Mars. Commercial power can be beamed from the Moon to ion-propelled rockets and to industrial facilities throughout the inner solar systems (6, 7). The LSP System can establish the Earth and the Moon as a two-planet economy. Lunar and cis-lunar industry will grow through profitable activities. Exploration of the inner solar system can stage, at marginal cost, from the Moon and cis-lunar space rather than the surface of Earth. 1. World Energy Council (2000) Energy for Tomorrow's World - Acting Now!, 175pp., Atalink Projects Ltd, London. 2. Criswell, David R. (2001) Lunar Solar Power System: Industrial Research, Development, and Demonstration, Session 1.2.2: Hydroelectricity, Nuclear Energy and New Renewables, 18th World Energy Congress. [http://www.wec.co.uk] 3. Strong, Marice (2001) Where on Earth are We Going?, (See p. 351-352), 419pp., Random House (forward by Kofi Annan) 4. Criswell, D. R. And R. D. Waldron (1993), "International lunar base and the lunar-based power system to supply Earth with electric power," Acta Astronautica, 29, No. 6: 469-480. 5. Criswell, D. R. (1998), Lunar Solar Power: Lunar unit processes, scales, and challenges, 6 p.p. (ms), ExploSpace: Workshop on Space Exploration and Resources Exploitation, European Space Agency, Cagliari, Sardinia, (October 20 - 22). 6. Criswell, D. R. (1999), Commercial lunar solar power and sustainable growth of the two-planet economy, Proc. Third International Working Group on Lunar Exploration and Exploitation, Solar System Research, Vol. 33, #5, 356-362, Moscow, (October 11-14). 7. Criswell, D.R. 2000 (October) Commercial power for Earth and lunar industrial development, 7pp., 51st Congress of the International Astronautical Federation (IAF). (Rio de Janeiro, Brazil). Paper #IAA-00-IAA.13.2.06.

Some thoughts on Mercurian resources

NASA Astrophysics Data System (ADS)

Gillett, Stephen L.

Virtually all scenarios on Solar System development ignore Mercury, but such inattention is probably undeserved. Once viable lunar and (probably) asteroidal facilities are established in the next century, Mercury warrants further investigation. Mercury's high solar energy density is a major potential advantage for space-based industries. Indeed, despite its higher gravity, Mercury is roughly twice as easy to leave as the Moon if the additional solar flux is taken into account. Moreover, with solar-driven technologies such as solar sails or electric propulsion, its depth in the Sun's gravity well is less important. Because Mercury is airless and almost certainly waterless, it will be an obvious place to export lunar technology, which will have been developed to deal with very similar conditions. Methods for extracting resources from anhydrous silicates will be particularly germane. Even without solar-powered propulsion, the discovery of low-delta-V access via multiple Venus and Earth encounters makes the planet easier to reach than had been thought. Technology developed for multi-year missions to asteroids and Mars should be readily adaptable to such Mercurian missions. Mercury will not be our first outpost in the Solar System. Nonetheless, as facilities are established in cis-Earth space, it probably merits attention as a next step for development.

Space solar cell research: Problems and potential

NASA Technical Reports Server (NTRS)

Flood, D. J.

1986-01-01

The value of a passive, maintenance-free, renewable energy source was apparent in the early days of the space program, and the silicon solar cell was pressed into service. Efficiencies of those early space solar arrays were low, and lifetimes shorter than hoped for, but within a decade significant advances had been made in both areas. Better performance was achieved through improvements in silicon single crystal material, better device designs, and a better understanding of the factors that affect the performance of a solar cell in space. Chief among the latter, particularly for the mid-to-high altitude (HEO) and geosynchronous (GEO) orbits, are the effects of the naturally occurring particulate radiation environment. Although not as broadly important to the photovoltaic community at large as increased efficiency, the topic of radiation damage is critically important to use of solar cells in space, and is a major component of the NASA research program in space photovoltaics. A brief overview of some of the opportunities and challenges for space photovoltaic applications is given, and some of the current research directed at achieving high efficiency and controlling radiation damage in space solar cells is discussed.

Monitoring and Modeling Astronaut Occupational Radiation Exposures in Space: Recent Advances

NASA Technical Reports Server (NTRS)

Weyland, Mark; Golightly, Michael

1999-01-01

In 1982 astronauts were declared to be radiation workers by OSHA, and as such were subject to the rules and regulations applied to that group. NASA was already aware that space radiation was a hazard to crewmembers and had been studying and monitoring astronaut doses since 1962 at the Johnson Space Center. It was quickly realized NASA would not be able to accomplish all of its goals if the astronauts were subject to the ground based radiation worker limits, and thus received a waiver from OSHA to establish independent limits. As part of the stipulation attached to setting new limits, OSHA included a requirement to perform preflight dose projections for each crew and inform them of the associated risks. Additional requirements included measuring doses from various sources during the flight, making every effort to prevent a crewmember from exceeding the new limits, and keeping all exposures As Low As Reasonably Achievable (a.k.a. ALARA - a common health physics principle). The assembly of the International Space Station (ISS) and its initial manned operations will coincide with the 4-5 year period of high space weather activity at the next maximum in the solar cycle. For the first time in NASA's manned program, US astronauts will be in orbit continuously throughout a solar maximum period. During this period, crews are at risk of significantly increased radiation exposures due to solar particle events and trapped electron belt enhancements following geomagnetic storms. The problem of protecting crews is compounded by the difficulty of providing continuous real-time monitoring over a period of a decade in an era of tightly constrained budgets. In order to prepare for ISS radiological support needs, the NASA Space Radiation Analysis Group and the NOAA Space Environment Center have undertaken a multiyear effort to improve and automate ground-based space weather monitoring systems and real-time radiation analysis tools. These improvements include a coupled, automated space weather monitoring and alarm system--SPE exposure analysis system, an advanced space weather data distribution and display system, and a high-fidelity space weather simulation system. In addition, significant new real-time space weather data sets, which will enhance the forecasting and now-casting of near-Earth space environment conditions, are being made available through unique NASA-NOAA-USAF collaborations. These new data sets include coronal mass ejection monitoring by the Solar and Heliospheric Observatory (SOHO) and in-situ plasma and particle monitoring at the L1 libration point by the Solar Wind Monitor (SWIM) and Advanced Composition Explorer (ACE) spacecraft. Advanced real-time radiation monitoring data from charged particle telescopes and tissue equivalent proportional counters will also be available to assist crew and flight controllers in monitoring the external and intravehicular radiation environment.

Electrostatic Discharge Test of Multi-Junction Solar Array Coupons After Combined Space Environmental Exposures

NASA Technical Reports Server (NTRS)

Wright, Kenneth H.; Schneider, Todd; Vaughn, Jason; Hoang, Bao; Funderburk, Victor V.; Wong, Frankie; Gardiner, George

2010-01-01

A set of multi-junction GaAs/Ge solar array test coupons were subjected to a sequence of 5-year increments of combined environmental exposure tests. The test coupons capture an integrated design intended for use in a geosynchronous (GEO) space environment. A key component of this test campaign is conducting electrostatic discharge (ESD) tests in the inverted gradient mode. The protocol of the ESD tests is based on the ISO/CD 11221, the ISO standard for ESD testing on solar array panels. This standard is currently in its final review with expected approval in 2010. The test schematic in the ISO reference has been modified with Space System/Loral designed circuitry to better simulate the on-orbit operational conditions of its solar array design. Part of the modified circuitry is to simulate a solar array panel coverglass flashover discharge. All solar array coupons used in the test campaign consist of 4 cells. The ESD tests are performed at the beginning of life (BOL) and at each 5-year environment exposure point. The environmental exposure sequence consists of UV radiation, electron/proton particle radiation, thermal cycling, and ion thruster plume. This paper discusses the coverglass flashover simulation, ESD test setup, and the importance of the electrical test design in simulating the on-orbit operational conditions. Results from 5th-year testing are compared to the baseline ESD characteristics determined at the BOL condition.

West Chester Work Center Solar Space Heating Demonstration Project. Interim test and evaluation report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1979-07-01

This document reports on the test and evaluation stage of a solar space heating demonstration project. It describes an integrated system providing solar energy space heating for a 9982 sq ft, newly built, one-story building. The building is located at 966 Matlack Street, West Goshen Township, Chester County, Pennsylvania. Functionally, the building consists of two sections: an office and a storeroom. The office section is heated by solar-assisted water-to-air heat pump units. The storeroom section is heated by an air-handling unit, containing a water-to-air coil. The system design was based on solar energy providing 62% of the heating load, withmore » the balance to be supplied by a back-up electric boiler. The system includes 1900 active (2112 gross) square feet of flat-plate solar collectors, and a 6000 gallon above-ground indoor storage tank. Freeze protection is provided by a gravity drain-down scheme combined with nitrogen pressurization in a closed circuit. System operation during the 1977 to 1978 heating season disclosed some major deficiencies in both the design and installation of the system, which caused the system to freeze and required it to be shut down for prolonged periods. Several major modifications and repairs were undergone during 1978 and are described in detail. System operation during the 1978 to 1979 heating season showed noticeable gradual improvement.« less

Space photovoltaic modules based on reflective optics

NASA Technical Reports Server (NTRS)

Andreev, V. M.; Larionov, V. R.; Rumyantsev, V. D.; Shvarts, M. Z.

1995-01-01

The conceptual design and experimental results for two types of space application concentrator photovoltaic modules, employing reflective optical elements, are presented. The first type is based on the use of compound parabolic concentrators, the second type is based on the use of line-focus parabolic troughs. Lightweight concentrators are formed with nickel foil coated silver with a diamond-like carbon layer protection. Secondary optical elements, including lenses and cones, are introduced for a better matching of concentrators and solar cells. Both types of modules are characterized by concentration ratios in the range 20x to 30x, depending on the chosen range of misorientation angles. The estimated specific parameters of these modules operating with single junction AlGaAs/GaAs solar cells are 240 W/sq m and 3 kg/sq m.

In-Space Transportation for Geo Space Solar Satellites

NASA Technical Reports Server (NTRS)

Martin, James A.; Donahue, Benjamin B.; Lawrence, Schuyler C.; McClanahan, James A.; Carrington, Connie (Technical Monitor)

2000-01-01

Space solar power satellites have the potential to provide abundant quantities of electricity for use on Earth. One concept, the Sun Tower, can be assembled in geostationary orbit from pieces transferred from Earth. The cost of transportation from Earth is one of the major hurdles to space solar power. This study found that a two-stage rocket launch vehicle with autonomous solar-electric transfer can provide the transportation at prices close to the goal of $800/kg

Characterization of Candidate Solar Sail Material Exposed to Space Environmental Effects

NASA Technical Reports Server (NTRS)

Edwards, David; Hovater, Mary; Hubbs, Whitney; Wertz, George; Hollerman, William; Gray, Perry

2003-01-01

Solar sailing is a unique form of propulsion where a spacecraft gains momentum from incident photons. Solar sails are not limited by reaction mass and provide continual acceleration, reduced only by the lifetime of the lightweight film in the space environment and the distance to the Sun. Once thought to be difficult or impossible, solar sailing has come out of science fiction and into the realm of possibility. Any spacecraft using this method would need to deploy a thin sail that could be as large as many kilometers in extent. The availability of strong, ultra lightweight, and radiation resistant materials will determine the future of solar sailing. The National Aeronautics and Space Administration's Marshall Space Flight Center (MSFC) is concentrating research into the utilization of ultra lightweight materials for spacecraft propulsion. The Space Environmental Effects Team at MSFC is actively characterizing candidate solar sail material to evaluate the thermo-optical and mechanical properties after exposure to space environmental effects. This paper will describe the exposure of candidate solar sail materials to emulated space environmental effects including energetic electrons, combined electrons and Ultraviolet radiation, and hypervelocity impact of irradiated solar sail material. This paper will describe the testing procedure and the material characterization results of this investigation.

A Space Weather Forecasting System with Multiple Satellites Based on a Self-Recognizing Network

PubMed Central

Tokumitsu, Masahiro; Ishida, Yoshiteru

2014-01-01

This paper proposes a space weather forecasting system at geostationary orbit for high-energy electron flux (>2 MeV). The forecasting model involves multiple sensors on multiple satellites. The sensors interconnect and evaluate each other to predict future conditions at geostationary orbit. The proposed forecasting model is constructed using a dynamic relational network for sensor diagnosis and event monitoring. The sensors of the proposed model are located at different positions in space. The satellites for solar monitoring equip with monitoring devices for the interplanetary magnetic field and solar wind speed. The satellites orbit near the Earth monitoring high-energy electron flux. We investigate forecasting for typical two examples by comparing the performance of two models with different numbers of sensors. We demonstrate the prediction by the proposed model against coronal mass ejections and a coronal hole. This paper aims to investigate a possibility of space weather forecasting based on the satellite network with in-situ sensing. PMID:24803190

A space weather forecasting system with multiple satellites based on a self-recognizing network.

PubMed

Tokumitsu, Masahiro; Ishida, Yoshiteru

2014-05-05

This paper proposes a space weather forecasting system at geostationary orbit for high-energy electron flux (>2 MeV). The forecasting model involves multiple sensors on multiple satellites. The sensors interconnect and evaluate each other to predict future conditions at geostationary orbit. The proposed forecasting model is constructed using a dynamic relational network for sensor diagnosis and event monitoring. The sensors of the proposed model are located at different positions in space. The satellites for solar monitoring equip with monitoring devices for the interplanetary magnetic field and solar wind speed. The satellites orbit near the Earth monitoring high-energy electron flux. We investigate forecasting for typical two examples by comparing the performance of two models with different numbers of sensors. We demonstrate the prediction by the proposed model against coronal mass ejections and a coronal hole. This paper aims to investigate a possibility of space weather forecasting based on the satellite network with in-situ sensing.

International Space Station Columbus Payload SoLACES Degradation Assessment

NASA Technical Reports Server (NTRS)

Hartman, William A.; Schmidl, William D.; Mikatarian, Ron; Soares, Carlos; Schmidtke, Gerhard; Erhardt, Christian

2016-01-01

SOLAR is a European Space Agency (ESA) payload deployed on the International Space Station (ISS) and located on the Columbus Laboratory. It is located on the Columbus External Payload Facility in a zenith location. The objective of the SOLAR payload is to study the Sun. The SOLAR payload consists of three instruments that allow for measurement of virtually the entire electromagnetic spectrum (17 nm to 2900 nm). The three payload instruments are SOVIM (SOlar Variable and Irradiance Monitor), SOLSPEC (SOLar SPECctral Irradiance measurements), and SolACES (SOLar Auto-Calibrating Extreme UV/UV Spectrophotometers).

The Telecommunications and Data Acquisition Report

NASA Technical Reports Server (NTRS)

Posner, Edward C. (Editor)

1991-01-01

This quarterly publication provides archival reports on developments in programs managed by JPL's Office of Telecommunications and Data Acquisition (TDA). In space communications, radio navigation, radio science, and ground-based radio and radar astronomy, it reports on activities of the Deep Space Network (DSN). Also included is standards activity at JPL for space data and information systems and reimbursable DSN work performed for other space agencies through NASA. In the search for extraterrestrial intelligence (SETI), 'The TDA Progress Report' reports on implementation and operations for searching the microwave spectrum. In solar system radar, it reports on the uses of the Goldstone Solar System Radar for scientific exploration of the planets, their rings and satellites, asteroids, and comets. In radio astronomy, the areas of support include spectroscopy, very long baseline interferometry, and astrometry.

Reduction of Martian Sample Return Mission Launch Mass with Solar Sail Propulsion

NASA Technical Reports Server (NTRS)

Russell, Tiffany E.; Heaton, Andy F.; Young, Roy; Baysinger, Mike; Schnell, Andrew R.

2013-01-01

Solar sails have the potential to provide mass and cost savings for spacecraft traveling within the innter solar system. Companies like L'Garde have demonstrated sail manufacturability and various i-space development methods. The purpose of this study was to evaluate a current Mars sample return architecture and to determine how cost and mass would be reduced by incorporating a solar sail propulsion system. The team validated the design proposed by L'Garde, and scaled the design based on a trajectory analysis. Using the solar sail design reduced the required mass, eliminating one of the three launches required in the original architecture.

Reduction of Martian Sample Return Mission Launch Mass with Solar Sail Propulsion

NASA Technical Reports Server (NTRS)

Russell, Tiffany E.; Heaton, Andrew; Thomas, Scott; Thomas, Dan; Young, Roy; Baysinger, Mike; Capizzo, Pete; Fabisinski, Leo; Hornsby, Linda; Maples, Dauphne;

Design review of the Brazilian Experimental Solar Telescope

NASA Astrophysics Data System (ADS)

Dal Lago, A.; Vieira, L. E. A.; Albuquerque, B.; Castilho, B.; Guarnieri, F. L.; Cardoso, F. R.; Guerrero, G.; Rodríguez, J. M.; Santos, J.; Costa, J. E. R.; Palacios, J.; da Silva, L.; Alves, L. R.; Costa, L. L.; Sampaio, M.; Dias Silveira, M. V.; Domingues, M. O.; Rockenbach, M.; Aquino, M. C. O.; Soares, M. C. R.; Barbosa, M. J.; Mendes, O., Jr.; Jauer, P. R.; Branco, R.; Dallaqua, R.; Stekel, T. R. C.; Pinto, T. S. N.; Menconi, V. E.; Souza, V. M. C. E. S.; Gonzalez, W.; Rigozo, N.

2015-12-01

The Brazilian's National Institute for Space Research (INPE), in collaboration with the Engineering School of Lorena/University of São Paulo (EEL/USP), the Federal University of Minas Gerais (UFMG), and the Brazilian's National Laboratory for Astrophysics (LNA), is developing a solar vector magnetograph and visible-light imager to study solar processes through observations of the solar surface magnetic field. The Brazilian Experimental Solar Telescope is designed to obtain full disk magnetic field and line-of-sight velocity observations in the photosphere. Here we discuss the system requirements and the first design review of the instrument. The instrument is composed by a Ritchey-Chrétien telescope with a 500 mm aperture and 4000 mm focal length. LCD polarization modulators will be employed for the polarization analysis and a tuning Fabry-Perot filter for the wavelength scanning near the Fe II 630.25 nm line. Two large field-of-view, high-resolution 5.5 megapixel sCMOS cameras will be employed as sensors. Additionally, we describe the project management and system engineering approaches employed in this project. As the magnetic field anchored at the solar surface produces most of the structures and energetic events in the upper solar atmosphere and significantly influences the heliosphere, the development of this instrument plays an important role in advancing scientific knowledge in this field. In particular, the Brazilian's Space Weather program will benefit most from the development of this technology. We expect that this project will be the starting point to establish a strong research program on Solar Physics in Brazil. Our main aim is to progressively acquire the know-how to build state-of-art solar vector magnetograph and visible-light imagers for space-based platforms.

Man's future in space

NASA Technical Reports Server (NTRS)

Freitag, R. F.

1975-01-01

Studies evaluating potential operational and commercial uses of space are being conducted, taking into account astronomy, astrophysics, manned bases and laboratories in earth orbit, space colonization, terrestrial communications, space processing and manufacturing, interstellar probes, planetary exploration, and the use of space for terrestrial energy supply. The present status in the exploration of the solar system is examined, giving attention to Jupiter, Venus, Mars, and Mercury. A brief outline of the development of human colonies on Mars is presented.

Development of Thin Solar Cells for Space Applications at NASA Glenn Research Center

NASA Technical Reports Server (NTRS)

Dickman, John E.; Hepp, Aloysius; Banger, Kulbinder K.; Harris, Jerry D.; Jin, Michael H.

2003-01-01

NASA GRC Thin Film Solar Cell program is developing solar cell technologies for space applications which address two critical metrics: higher specific power (power per unit mass) and lower launch stowed volume. To be considered for space applications, an array using thin film solar cells must offer significantly higher specific power while reducing stowed volume compared to the present technologies being flown on space missions, namely crystalline solar cells. The NASA GRC program is developing single-source precursors and the requisite deposition hardware to grow high-efficiency, thin-film solar cells on polymer substrates at low deposition temperatures. Using low deposition temperatures enables the thin film solar cells to be grown on a variety of polymer substrates, many of which would not survive the high temperature processing currently used to fabricate thin film solar cells. The talk will present the latest results of this research program.

Solar energy concentrator system for crystal growth and zone refining in space

NASA Technical Reports Server (NTRS)

Mcdermit, J. H.

1975-01-01

The technological feasibility of using solar concentrators for crystal growth and zone refining in space has been performed. Previous studies of space-deployed solar concentrators were reviewed for their applicability to materials processing and a new state-of-the-art concentrator-receiver radiation analysis was developed. The radiation analysis is in the form of a general purpose computer program. It was concluded from this effort that the technology for fabricating, orbiting and deploying large solar concentrators has been developed. It was also concluded that the technological feasibility of space processing materials in the focal region of a solar concentrator depends primarily on two factors: (1) the ability of a solar concentrator to provide sufficient thermal energy for the process and (2) the ability of a solar concentrator to provide a thermal environment that is conductive to the processes of interest. The analysis indicate that solar concentrators can satisfactorily provide both of these factors.

A Solar Dynamic Power Option for Space Solar Power

NASA Technical Reports Server (NTRS)

Mason, Lee S.

1999-01-01

A study was performed to determine the potential performance and related technology requirements of Solar Dynamic power systems for a Space Solar Power satellite. Space Solar Power is a concept where solar energy is collected in orbit and beamed to Earth receiving stations to supplement terrestrial electric power service. Solar Dynamic systems offer the benefits of high solar-to-electric efficiency, long life with minimal performance degradation, and high power scalability. System analyses indicate that with moderate component development, SD systems can exhibit excellent mass and deployed area characteristics. Using the analyses as a guide, a technology roadmap was -enerated which identifies the component advances necessary to make SD power generation a competitive option for the SSP mission.

Solar Week: Learning from Experience

NASA Astrophysics Data System (ADS)

Alexander, D.; Hauck, K.

2003-12-01

Solar Week is a week-long set of games and activities allowing students to interact directly with solar science and solar scientists. Solar Week was developed as a spin-off of the highly successful Yohkoh Public Outreach Project (YPOP). While YPOP provided access to solar images, movies and activities, the main goal of Solar Week was to enhance the participation of women, who are under-represented in the physical sciences. Solar Week achieves this by providing young women, primarily in grades 6-8, with access to role models in the sciences. The scientists participating in Solar Week are women from a variety of backgrounds and with a variety of scientific expertise. In this paper, our aim is to provide some insight into developing activity-based space science for the web and to discuss the lessons-learned from tailoring to a specific group of participants.

AlGaAs top solar cell for mechanical attachment in a multi-junction tandem concentrator solar cell stack

NASA Technical Reports Server (NTRS)

Dinetta, L. C.; Hannon, M. H.; Mcneely, J. B.; Barnett, A. M.

1991-01-01

The AstroPower self-supporting, transparent AlGaAs top solar cell can be stacked upon any well-developed bottom solar cell for improved system performance. This is an approach to improve the performance and scale of space photovoltaic power systems. Mechanically stacked tandem solar cell concentrator systems based on the AlGaAs top concentrator solar cell can provide near term efficiencies of 36 percent (AMO, 100x). Possible tandem stack efficiencies greater than 38 percent (100x, AMO) are feasible with a careful selection of materials. In a three solar cell stack, system efficiencies exceed 41 percent (100x, AMO). These device results demonstrate a practical solution for a state-of-the-art top solar cell for attachment to an existing, well-developed solar cell.

Thin-Film Solar Cells on Polymer Substrates for Space Power

NASA Technical Reports Server (NTRS)

Hepps, A. F.; McNatt, Jeremiah; Morel, D. L.; Ferckides, C. S.; Jin, M. H.; Orbey, N.; Cushman, M.; Birkmire, R. W.; Shafarman, W. N.; Newton, R.

2004-01-01

Photovoltaic arrays have played a key role in power generation in space. The current technology will continue to evolve but is limited in the important mass specific power metric (MSP or power/weight ratio) because it is based on bulk crystal technology. Solar cells based on thin-film materials offer the promise of much higher MSP and much lower cost. However, for many space applications, a 20% or greater AM0 efficiency (eta) may be required. The leading thin-film materials, amorphous Si, CuInSe, and CdTe have seen significant advances in efficiency over the last decade but will not achieve the required efficiency in the near future. Several new technologies are herein described to maximize both device eta and MSP. We will discuss these technologies in the context of space exploration and commercialization. One novel approach involves the use of very lightweight polyimide substrates. We describe efforts to enable this advance including materials processing and device fabrication and characterization. Another approach involves stacking two cells on top of each other. These tandem devices more effectively utilize solar radiation by passing through non-absorbed longer wavelength light to a narrow-bandgap bottom cell material. Modeling of current devices in tandem format indicates that AM0 efficiencies near 20% can be achieved with potential for 25% in the near future. Several important technical issues need to be resolved to realize the benefits of lightweight technologies for solar arrays, such as: monolithic interconnects, lightweight array structures, and new ultra-light support and deployment mechanisms. Recent advances will be stressed.

Methods for Cloud Cover Estimation

NASA Technical Reports Server (NTRS)

Glackin, D. L.; Huning, J. R.; Smith, J. H.; Logan, T. L.

1984-01-01

Several methods for cloud cover estimation are described relevant to assessing the performance of a ground-based network of solar observatories. The methods rely on ground and satellite data sources and provide meteorological or climatological information. One means of acquiring long-term observations of solar oscillations is the establishment of a ground-based network of solar observatories. Criteria for station site selection are: gross cloudiness, accurate transparency information, and seeing. Alternative methods for computing this duty cycle are discussed. The cycle, or alternatively a time history of solar visibility from the network, can then be input to a model to determine the effect of duty cycle on derived solar seismology parameters. Cloudiness from space is studied to examine various means by which the duty cycle might be computed. Cloudiness, and to some extent transparency, can potentially be estimated from satellite data.

Little Eyes on Large Solar Motions

NASA Astrophysics Data System (ADS)

Kohler, Susanna

2017-10-01

Images taken during the solar eclipse in 2012. The central color composite of the eclipsed solar surface was captured by SDO, the white-light view of the solar corona around it was taken by the authors, and the background, wide-field black-and-white view is from LASCO. The white arrows mark the atypical structure. [Alzate et al. 2017]It seems like science is increasingly being done with advanced detectors on enormous ground- and space-based telescopes. One might wonder: is there anything left to learn from observations made with digital cameras mounted on 10-cm telescopes?The answer is yes plenty! Illustrating this point, a new study using such equipment recently reports on the structure and dynamics of the Suns corona during two solar eclipses.A Full View of the CoronaThe solar corona is the upper part of the Suns atmosphere, extending millions of kilometers into space. This plasma is dynamic, with changing structures that arise in response to activity on the Suns surface such as enormous ejections of energy known as coronal mass ejections (CMEs). Studying the corona is therefore important for understanding what drives its structure and how energy is released from the Sun.Though there exist a number of space-based telescopes that observe the Suns corona, they often have limited fields of view. The Solar Dynamics Observatory AIA, for instance, has spectacular resolution but only images out to 1/3 of a solar radius above the Suns limb. The space-based coronagraph LASCO C2, on the other hand, provides a broad view of the outer regions of the corona, but it only images down to 2.2 solar radii above the Suns limb. Piecing together observations from these telescopes therefore leaves a gap that prevents a full picture of the large-scale corona and how it connects to activity at the solar surface.Same as the previous figure, but for the eclipse in 2013. [Alzate et al. 2017]To provide this broad, continuous picture, a team of scientists used digital cameras mounted on 10-cm telescopes to capture white-light images from the solar surface out to several solar radii using a natural coronagraph: a solar eclipse. The team made two sets of observations: one during an eclipse in 2012 in Australia, and one during an eclipse in 2013 in Gabon, Africa. In a recent publication led by Nathalia Alzate (Honolulu Community College), the team now reports what they learned from these observations.Building Atypical StructuresThe authors image processing revealed two atypical large-scale structures with sharp edges, somewhat similar in appearance to what is seen near the boundaries of rapidly expanding polar coronal holes. But these structures, visible in the southeast quadrant of the images taken during both eclipses, were not located near the poles.By analyzing their images along with space-based images taken at the same time, Alzate and collaborators were able to determine that the shape the structures took was instead a direct consequence of a series of sudden brightenings due to low-level flaring events on the solar surface. These events were followed by small jets, and then very faint, puff-like CMEs that might otherwise have gone unnoticed.Impact of the passage of a series of puff-like CMEs (shown in the LASCO time sequence in the bottom panels) on coronal structures. [Alzate et al. 2017]The fact that such innocuous transient events in the Suns lower atmosphere can be enough to influence the coronas large-scale structure for timescales of 1248 hours is a significant discovery. There are roughly 3 CMEs per day during solar maximum, suggesting that atypical structures like the ones discovered in these images are likely very common. These results therefore have a significant impact on our understanding of the solar corona which goes to show that theres still a lot we can learn with small telescopes!CitationNathalia Alzate et al 2017 ApJ 848 84. doi:10.3847/1538-4357/aa8cd2

Automatic prediction of solar flares and super geomagnetic storms

NASA Astrophysics Data System (ADS)

Song, Hui

Space weather is the response of our space environment to the constantly changing Sun. As the new technology advances, mankind has become more and more dependent on space system, satellite-based services. A geomagnetic storm, a disturbance in Earth's magnetosphere, may produce many harmful effects on Earth. Solar flares and Coronal Mass Ejections (CMEs) are believed to be the major causes of geomagnetic storms. Thus, establishing a real time forecasting method for them is very important in space weather study. The topics covered in this dissertation are: the relationship between magnetic gradient and magnetic shear of solar active regions; the relationship between solar flare index and magnetic features of solar active regions; based on these relationships a statistical ordinal logistic regression model is developed to predict the probability of solar flare occurrences in the next 24 hours; and finally the relationship between magnetic structures of CME source regions and geomagnetic storms, in particular, the super storms when the D st index decreases below -200 nT is studied and proved to be able to predict those super storms. The results are briefly summarized as follows: (1) There is a significant correlation between magnetic gradient and magnetic shear of active region. Furthermore, compared with magnetic shear, magnetic gradient might be a better proxy to locate where a large flare occurs. It appears to be more accurate in identification of sources of X-class flares than M-class flares; (2) Flare index, defined by weighting the SXR flares, is proved to have positive correlation with three magnetic features of active region; (3) A statistical ordinal logistic regression model is proposed for solar flare prediction. The results are much better than those data published in the NASA/SDAC service, and comparable to the data provided by the NOAA/SEC complicated expert system. To our knowledge, this is the first time that logistic regression model has been applied in solar physics to predict flare occurrences; (4) The magnetic orientation angle [straight theta], determined from a potential field model, is proved to be able to predict the probability of super geomagnetic storms (D= st <=-200nT). The results show that those active regions associated with | [straight theta]| < 90° are more likely to cause a super geomagnetic storm.

Remote sensing optical instrumentation for enhanced space weather monitoring from the L1 and L5 Lagrange points

NASA Astrophysics Data System (ADS)

Kraft, S.; Puschmann, K. G.; Luntama, J. P.

2017-09-01

As part of the Space Situational Awareness Programme (SSA), ESA has initiated the assessment of two missions currently foreseen to be implemented to enable enhanced space weather monitoring. These missions utilize the positioning of satellites at the Lagrangian L1 and L5 points. These Phase 0 or Pre-Phase A mission studies are about to be completed and will thereby have soon passed the Mission Definition Review. Phase A studies are planned to start in 2017. The space weather monitoring system currently considers four remote sensing optical instruments and several in-situ instruments to analyse the Sun and the solar wind conditions, in order to provide early warnings of increased solar activity and to identify and mitigate potential threats to society and ground, airborne and space based infrastructure. The suggested optical instruments take heritage from ESA and NASA science missions like SOHO, STEREO and Solar Orbiter, but the instruments are foreseen to be optimized for operational space weather monitoring purposes with high reliability and robustness demands. The instruments are required to provide high quality measurements particularly during severe space weather events. The program intends to utilize the results of the on-going ESA instrument prototyping and technology development activities, and to initiate pre-developments of the operational space weather instruments to ensure the required maturity before the mission implementation.

Determination of Thermal State of Charge in Solar Heat Receivers

NASA Technical Reports Server (NTRS)

Glakpe, E. K.; Cannon, J. N.; Hall, C. A., III; Grimmett, I. W.

1996-01-01

The research project at Howard University seeks to develop analytical and numerical capabilities to study heat transfer and fluid flow characteristics, and the prediction of the performance of solar heat receivers for space applications. Specifically, the study seeks to elucidate the effects of internal and external thermal radiation, geometrical and applicable dimensionless parameters on the overall heat transfer in space solar heat receivers. Over the last year, a procedure for the characterization of the state-of-charge (SOC) in solar heat receivers for space applications has been developed. By identifying the various factors that affect the SOC, a dimensional analysis is performed resulting in a number of dimensionless groups of parameters. Although not accomplished during the first phase of the research, data generated from a thermal simulation program can be used to determine values of the dimensionless parameters and the state-of-charge and thereby obtain a correlation for the SOC. The simulation program selected for the purpose is HOTTube, a thermal numerical computer code based on a transient time-explicit, axisymmetric model of the total solar heat receiver. Simulation results obtained with the computer program are presented the minimum and maximum insolation orbits. In the absence of any validation of the code with experimental data, results from HOTTube appear reasonable qualitatively in representing the physical situations modeled.

KSC-08pd2418

NASA Image and Video Library

2008-08-05

VANDENBERG AIR FORCE BASE, Calif. – At Vandenberg Air Force Base in California, the Star-27 kick motor and nozzle for NASA's Interstellar Boundary Explorer, or IBEX, spacecraft are “on top” and part of the IBEX flight system, known as the adapter cone, is in the foreground/bottom. The Star-27 motor has a silver tank that contains the solid propellant. The nozzle fits down inside the adapter cone. The IBEX satellite will make the first map of the boundary between the Solar System and interstellar space. IBEX is the first mission designed to detect the edge of the Solar System. As the solar wind from the sun flows out beyond Pluto, it collides with the material between the stars, forming a shock front. IBEX contains two neutral atom imagers designed to detect particles from the termination shock at the boundary between the Solar System and interstellar space. IBEX also will study galactic cosmic rays, energetic particles from beyond the Solar System that pose a health and safety hazard for humans exploring beyond Earth orbit. IBEX will make these observations from a highly elliptical orbit that takes it beyond the interference of the Earth's magnetosphere. IBEX is targeted for launch from the Pegasus XL rocket on Oct. 5. Photo credit: NASA/R. Bledsoe

Energy Action Day

NASA Image and Video Library

2017-10-25

Chuck Tatro of NASA's Launch Services Program discusses the use of solar arrays on space science missions during the Energy Action Day employee event held in Kennedy Space Center's Space Station Processing Facility. Part of Energy Awareness Month, the event featured subject matter experts in the area of solar energy, its connections to the space program and options for residential solar power.

Performance of evacuated tubular solar collectors in a residential heating and cooling system. Final report, 1 October 1978-30 September 1979

DOE Office of Scientific and Technical Information (OSTI.GOV)

Duff, W.S.; Loef, G.O.G.

1981-03-01

Operation of CSU Solar House I during the heating season of 1978-1979 and during the 1979 cooling season was based on the use of systems comprising an experimental evacuated tubular solar collector, a non-freezing aqueous collection medium, heat exchange to an insulated conventional vertical cylindrical storage tank and to a built-up rectangular insulated storage tank, heating of circulating air by solar heated water and by electric auxiliary in an off-peak heat storage unit, space cooling by lithium bromide absorption chiller, and service water heating by solar exchange and electric auxiliary. Automatic system control and automatic data acquisition and computation aremore » provided. This system is compared with others evaluated in CSU Solar Houses I, II and III, and with computer predictions based on mathematical models. Of the 69,513 MJ total energy requirement for space heating and hot water during a record cold winter, solar provided 33,281 MJ equivalent to 48 percent. Thirty percent of the incident solar energy was collected and 29 percent was delivered and used for heating and hot water. Of 33,320 MJ required for cooling and hot water during the summer, 79 percent or 26,202 MJ were supplied by solar. Thirty-five percent of the incident solar energy was collected and 26 percent was used for hot water and cooling in the summer. Although not as efficient as the Corning evacuated tube collector previously used, the Philips experimental collector provides solar heating and cooling with minimum operational problems. Improved performance, particularly for cooling, resulted from the use of a very well-insulated heat storage tank. Day time (on-peak) electric auxiliary heating was completely avoided by use of off-peak electric heat storage. A well-designed and operated solar heating and cooling system provided 56 percent of the total energy requirements for heating, cooling, and hot water.« less

Preliminary design and cost of a 1-megawatt solar-pumped iodide laser space-to-space transmission station

NASA Technical Reports Server (NTRS)

Deyoung, R. J.; Walker, G. H.; Williams, M. D.; Schuster, G. L.; Conway, E. J.

1987-01-01

A preliminary conceptual design of a space-based solar pumped iodide laser emitting 1 megawatt of laser power for space-to-space power transmission is described. A near parabolic solar collector focuses sunlight onto the t-C4F9I (perfluoro-t butyl iodide) lasant within a transverse flow optical cavity. Using waste heat, a thermal system was designed to supply compressor and auxiliary power. System components were designed with weight and cost estimates assigned. Although cost is very approximate, the cost comparison of individual system components leads to valuable insights for future research. In particular, it was found that laser efficiency was not a dominant cost or weight factor, the dominant factor being the laser cavity and laser transmission optics. The manufacturing cost was approx. two thirds of the total cost with transportation to orbit the remainder. The flowing nonrenewable lasant comprised 20% of the total life cycle cost of the system and thus was not a major cost factor. The station mass was 92,000 kg without lasant, requiring approx. four shuttle flights to low Earth orbit where an orbital transfer vehicle will transport it to the final altitude of 6378 km.

Design investigation of solar-powered lasers for space applications

NASA Technical Reports Server (NTRS)

1982-01-01

The feasibility of using solar powered continuous wave (CW) lasers for space power transmission was investigated. Competing conceptual designs are considered. Optical pumping is summarized. Solar pumped Lasant type lasers are outlined. Indirect solar pumped lasers are considered.

High Photon-to-Current Conversion in Solar Cells Based on Light-Absorbing Silver Bismuth Iodide.

PubMed

Zhu, Huimin; Pan, Mingao; Johansson, Malin B; Johansson, Erik M J

2017-06-22

Here, a lead-free silver bismuth iodide (AgI/BiI 3 ) with a crystal structure with space group R3‾ m is investigated for use in solar cells. Devices based on the silver bismuth iodide deposited from solution on top of TiO 2 and the conducting polymer poly(3-hexylthiophene-2,5-diyl) (P3HT) as a hole-transport layer are prepared and the photovoltaic performance is very promising with a power conversion efficiency over 2 %, which is higher than the performance of previously reported bismuth-halide materials for solar cells. Photocurrent generation is observed between 350 and 700 nm, and the maximum external quantum efficiency is around 45 %. The results are compared to solar cells based on the previously reported material AgBi 2 I 7 , and we observe a clearly higher performance for the devices with the new silver and bismuth iodides composition and different crystal structure. The X-ray diffraction spectrum of the most efficient silver bismuth iodide material shows a hexagonal crystal structure with space group R3‾ m, and from the light absorption spectrum we obtain an indirect band gap energy of 1.62 eV and a direct band gap energy of 1.85 eV. This report shows the possibility for finding new structures of metal-halides efficient in solar cells and points out new directions for further exploration of lead-free metal-halide solar cells. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

Multiple NEO Rendezvous Using Solar Sail Propulsion

NASA Technical Reports Server (NTRS)

Johnson, Les; Alexander, Leslie; Fabisinski, Leo; Heaton, Andy; Miernik, Janie; Stough, Rob; Wright, Roosevelt; Young, Roy

2012-01-01

The NASA Marshall Space Flight Center (MSFC) Advanced Concepts Office performed an assessment of the feasibility of using a near-term solar sail propulsion system to enable a single spacecraft to perform serial rendezvous operations at multiple Near Earth Objects (NEOs) within six years of launch on a small-to-moderate launch vehicle. The study baselined the use of the sail technology demonstrated in the mid-2000 s by the NASA In-Space Propulsion Technology Project and is scheduled to be demonstrated in space by 2014 as part of the NASA Technology Demonstration Mission Program. The study ground rules required that the solar sail be the only new technology on the flight; all other spacecraft systems and instruments must have had previous space test and qualification. The resulting mission concept uses an 80-m X 80-m 3-axis stabilized solar sail launched by an Athena-II rocket in 2017 to rendezvous with 1999 AO10, Apophis and 2001 QJ142. In each rendezvous, the spacecraft will perform proximity operations for approximately 30 days. The spacecraft science payload is simple and lightweight; it will consist of only the multispectral imager flown on the Near Earth Asteroid Rendezvous (NEAR) mission to 433 Eros and 253 Mathilde. Most non-sail spacecraft systems are based on the Messenger mission spacecraft. This paper will describe the objectives of the proposed mission, the solar sail technology to be employed, the spacecraft system and subsystems, as well as the overall mission profile.

Assessing Space Weather Applications and Understanding: IMF Bz at L1

NASA Astrophysics Data System (ADS)

Riley, P.; Savani, N.; Mays, M. L.; Austin, H. J.

2017-12-01

The CCMC - International (CCMC-I) is designed as a self-organizing informal forum for facilitating novel global initiatives on space weather research, development, forecasting and education. Here we capitalize on CCMC'AGUs experience in providing highly utilized web-based services, leadership and trusted relationships with space weather model developers. One of the CCMC-I initiatives is the International Forum for Space Weather Capabilities Assessment. As part of this initiative, within the solar and heliosphere domain, we focus our community discussion on forecasting the magnetic structure of interplanetary CMEs and the ambient solar wind. During the International CCMC-LWS Working Meeting in April 2017 the group instigated open communication to agree upon a standardized process by which all current and future models can be compared under an unbiased test. In this poster, we present our initial findings how we expect different models will move forward with validating and forecasting the magnetic vectors of the solar wind at L1. We also present a new IMF Bz Score-board which will be used to assist in the transitioning of research models into more operational settings.

Design and Analysis of the Aperture Shield Assembly for a Space Solar Receiver

NASA Technical Reports Server (NTRS)

Strumpf, Hal J.; Trinh, Tuan; Westelaken, William; Krystkowiak, Christopher; Avanessian, Vahe; Kerslake, Thomas W.

1997-01-01

A joint U.S./Russia program has been conducted to design, develop, fabricate, launch, and operate the world's first space solar dynamic power system on the Russian Space Station Mir. The goal of the program was to demonstrate and confirm that solar dynamic power systems are viable for future space applications such as the International Space Station (ISS). The major components of the system include a solar receiver, a closed Brayton cycle power conversion unit, a power conditioning and control unit, a solar concentrator, a radiator, a thermal control system, and a Space Shuttle carrier. Unfortunately, the mission was demanifested from the ISS Phase 1 Space Shuttle Program in 1996. However, NASA Lewis is proposing to use the fabricated flight hardware as part of an all-American flight demonstration on the ISS in 2002. The present paper concerns the design and analysis of the solar receiver aperture shield assembly. The aperture shield assembly comprises the front face of the cylindrical receiver and is located at the focal plane of the solar concentrator. The aperture shield assembly is a critical component that protects the solar receiver structure from highly concentrated solar fluxes during concentrator off-pointing events. A full-size aperture shield assembly was fabricated. This unit was essentially identical to the flight configuration, with the exception of materials substitution. In addition, a thermal shock test aperture shield assembly was fabricated. This test article utilized the flight materials and was used for high-flux testing in the solar simulator test rig at NASA Lewis. This testing is described in a companion paper.

Solar total and spectral irradiance reconstruction over last 9000 years

NASA Astrophysics Data System (ADS)

Wu, Chi-Ju; Usoskin, Ilya; Krivova, Natalie; Solanki, Sami K.

2016-07-01

Although the mechanisms of solar influence on Earth climate system are not yet fully understood, solar total and spectral irradiance are considered to be among the main determinants. Solar total irradiance is the total flux of solar radiative energy entering Earth's climate system, whereas the spectral irradiance describes this energy is distributed over the spectrum. Solar irradiance in the UV band is of special importance since it governs chemical processes in the middle and upper atmosphere. On timescales of the 11-year solar cycle and shorter, solar irradiance is measured by space-based instruments while models are needed to reconstruct solar irradiance on longer timescale. The SATIRE-M model (Spectral And Total Irradiance Reconstruction over millennia) is employed in this study to reconstruct solar irradiance from decadal radionuclide isotope data such as 14C and 10Be stored in tree rings and ice cores, respectively. A reconstruction over the last 9000 years will be presented.

Solar Total and Spectral Irradiance Reconstruction over Last 9000 Years

NASA Astrophysics Data System (ADS)

Wu, C. J.; Krivova, N.; Solanki, S. K.; Usoskin, I. G.

2016-12-01

Although the mechanisms of solar influence on Earth climate system are not yet fully understood, solar total and spectral irradiance are considered to be among the main determinants. Solar total irradiance is the total flux of solar radiative energy entering Earth's climate system, whereas the spectral irradiance describes this energy is distributed over the spectrum. Solar irradiance in the UV band is of special importance since it governs chemical processes in the middle and upper atmosphere. On timescales of the 11-year solar cycle and shorter, solar irradiance is measured by space-based instruments while models are needed to reconstruct solar irradiance on longer timescale. The SATIRE-M model (Spectral And Total Irradiance Reconstruction over millennia) is employed in this study to reconstruct solar irradiance from decadal radionuclide isotope data such as 14C and 10Be stored in tree rings and ice cores, respectively. A reconstruction over the last 9000 years will be presented.

Development of standardized specifications for silicon solar cells

NASA Technical Reports Server (NTRS)

Scott-Monck, J. A.

1977-01-01

A space silicon solar cell assembly (cell and coverglass) specification aimed at standardizing the diverse requirements of current cell or assembly specifications was developed. This specification was designed to minimize both the procurement and manufacturing costs for space qualified silicon solar cell assembilies. In addition, an impact analysis estimating the technological and economic effects of employing a standardized space silicon solar cell assembly was performed.

Solar EUV irradiance for space weather applications

NASA Astrophysics Data System (ADS)

Viereck, R. A.

2015-12-01

Solar EUV irradiance is an important driver of space weather models. Large changes in EUV and x-ray irradiances create large variability in the ionosphere and thermosphere. Proxies such as the F10.7 cm radio flux, have provided reasonable estimates of the EUV flux but as the space weather models become more accurate and the demands of the customers become more stringent, proxies are no longer adequate. Furthermore, proxies are often provided only on a daily basis and shorter time scales are becoming important. Also, there is a growing need for multi-day forecasts of solar EUV irradiance to drive space weather forecast models. In this presentation we will describe the needs and requirements for solar EUV irradiance information from the space weather modeler's perspective. We will then translate these requirements into solar observational requirements such as spectral resolution and irradiance accuracy. We will also describe the activities at NOAA to provide long-term solar EUV irradiance observations and derived products that are needed for real-time space weather modeling.

Extreme Space Weather Events: From Cradle to Grave

NASA Astrophysics Data System (ADS)

Riley, Pete; Baker, Dan; Liu, Ying D.; Verronen, Pekka; Singer, Howard; Güdel, Manuel

2018-02-01

Extreme space weather events, while rare, can have a substantial impact on our technologically-dependent society. And, although such events have only occasionally been observed, through careful analysis of a wealth of space-based and ground-based observations, historical records, and extrapolations from more moderate events, we have developed a basic picture of the components required to produce them. Several key issues, however, remain unresolved. For example, what limits are imposed on the maximum size of such events? What are the likely societal consequences of a so-called "100-year" solar storm? In this review, we summarize our current scientific understanding about extreme space weather events as we follow several examples from the Sun, through the solar corona and inner heliosphere, across the magnetospheric boundary, into the ionosphere and atmosphere, into the Earth's lithosphere, and, finally, its impact on man-made structures and activities, such as spacecraft, GPS signals, radio communication, and the electric power grid. We describe preliminary attempts to provide probabilistic forecasts of extreme space weather phenomena, and we conclude by identifying several key areas that must be addressed if we are better able to understand, and, ultimately, predict extreme space weather events.

The U.S. Antarctic and space programs, a useful alliance

NASA Astrophysics Data System (ADS)

Wilkniss, Peter E.

Antarctica has been called 'Space on Earth' because the continent's extreme isolation, combining with extremely low temperatures, alternating cycles of light and dark, and the lack of any naturally occurring life support, simulates planetary conditions. For scientists, the polar regions, particularly the Antarctic, are 'Earth's window to outer space.' Originally, this term applied to this study of the aurora and other phenomena related top solar-terrestrial interactions. Today this concept has broadened considerably to include research on processes occurring near or on the Earth, such as the study of solar ultra-violet radiation and related processes resulting from the depletion of stratospheric ozone above Antarctica or the investigation of high-energy solar or galactic particles from sites in central Antarctica. The alliance between the antarctic and space science can be traced to 1957-the year that Sputnik was launched and modern science programs began during the International Geophysical Year. The National Science Foundation (NSF) and the National Aeronautics and Space Administration (NASA) have a long history of cooperative projects in the Antarctic. This collaboration ranges from the use of satellite- based technology for communications, research weather observations, and data acquisition to testing and calibrating equipment that will be used aboard space crafts. In January 1991, the two agencies signed a Memorandum of Agreement that will extend this collaboration.

Solar Sail Propulsion for Interplanetary Cubesats

NASA Technical Reports Server (NTRS)

Johnson, Les; Sobey, Alex; Sykes, Kevin

2015-01-01

NASA is developing two small satellite missions as part of the Advanced Exploration Systems (AES) Program, both of which will use a solar sail to enable their scientific objectives. Solar sails use sunlight to propel vehicles through space by reflecting solar photons from a large, mirror-like sail made of a lightweight, highly reflective material. This continuous photon pressure provides propellantless thrust, allowing for very high (Delta)V maneuvers on long-duration, deep space exploration. Since reflected light produces thrust, solar sails require no onboard propellant. Solar sail technology is rapidly maturing for space propulsion applications within NASA and around the world.

Solar energy system performance evaluation: Seasonal report for fern, Tunkhannock, Pennsylvania

NASA Technical Reports Server (NTRS)

1980-01-01

The operational and thermal performance of a variety of solar systems installed in operational test sites are described. The analysis is based on instrumented system data monitored and collected for at least one full season of operation. The long-term field performance of the installed system is reported, and technical contributions to the definition of techniques and requirements for solar energy system design are made. The solar energy system was designed to supply space heating and domestic hot water for single-family residences. The system consists of air flat plate collectors, storage tank, pumps, heat exchangers, associated plumbing, and controls.

NREL Inks Technology Agreement for High Efficiency Multijunction Solar

Science.gov Websites

) multijunction solar cells. While high-efficiency multijunction solar cells are commonly used for space Devices is excited to now be commercializing IMM solar cells for high-performance space and UAV Cells | News | NREL Inks Technology Agreement for High Efficiency Multijunction Solar Cells

Solar Physics in the Space Age.

ERIC Educational Resources Information Center

Dittmer, Phil D.; And Others

This amply illustrated booklet provides a physical description of the sun as well as present and future tasks for solar physics study. The first chapter, an introduction, describes the history of solar study, solar study in space, and the relevance of solar study. The second chapter describes the five heliographic domains including the interior,…

Solar Thermal Propulsion Concept

NASA Technical Reports Server (NTRS)

2004-01-01

Harnessing the Sun's energy through Solar Thermal Propulsion will propel vehicles through space by significantly reducing weight, complexity, and cost while boosting performance over current conventional upper stages. Another solar powered system, solar electric propulsion, demonstrates ion propulsion is suitable for long duration missions. Pictured is an artist's concept of space flight using solar thermal propulsion.

Spacecraft Maneuvering at the Sun/Earth-Moon L2 Libration Point

NASA Astrophysics Data System (ADS)

Shahid, Kamran

Spacecraft formation flying in the vicinity of the Sun/Earth-Moon libration points offers many promising possibilities for space exploration. The concept of formation flying involves the distribution of the functionality of a single spacecraft among several smaller, cooperative spacecraft. The libration points are locations relative to two large orbiting bodies where a third body with relatively small mass can remain stationary relative to the two larger bodies. The most significant perturbation experienced by a spacecraft at the libration point is effect of solar radiation pressure. This thesis presents the development of nonlinear control techniques for maneuvering control at the Sun-Earth/Moon L2 libration point. A new thruster based formation control technique is presented. We also consider a leader/follower formation architecture, and examine the station keeping control of the leader spacecraft and the formation control of the follower spacecraft using solar radiation pressure. Reference trajectories of the leader spacecraft, halo and Lissajous orbits, are determined using a numerical technique in order to take into account all major gravitational perturbations. The nonlinear controllers are developed based on Lyapunov analysis, including non-adaptive and adaptive designs. Thruster based and solar radiation pressure based control laws for spacecraft maneuvering at the Sun-Earth/Moon libration point are developed. Higher order sliding mode control is utilized to address the non-affine structure of the solar sail control inputs. The reduced input solar radiation pressure problem is properly addressed as an underactuated control problem. The development of adaptive control for solar sail equipped spacecraft is an innovation and represents and advancement in solar sailing control technology. Controller performance is evaluated in a high fidelity ephemeris model to reflect a realistic simulated space environment. The numerical results demonstrate the effectiveness of the proposed control techniques for spacecraft maneuvering using solar radiation pressure at the L2 libration point. Stationkeeping accuracies of 50m and formation maintenance accuracies of less than 1m are possible using solar radiation pressure at a sub-L2 libration point. The benefits of these control techniques include increasing libration point mission lifetimes and doubling payload mass fractions as compared to conventional propulsion methods.

The 2017 Total Solar Eclipse: Through the Eyes of NASA

NASA Astrophysics Data System (ADS)

Mayo, Louis; NASA Goddard Heliophysics Education Consortium

2017-10-01

The August 21st, 2017 Total Solar Eclipse Across America provided a unique opportunity to teach event-based science to nationwide audiences. NASA spent over three years planning space and Earth science education programs for informal audiences, undergraduate institutions, and life long learners to bring this celestial event to the public through the eyes of NASA. This talk outlines how NASA used its unique assets including mission scientists and engineers, space based assets, citizen science, educational technology, science visualization, and its wealth of science and technology partners to bring the eclipse to the country through multimedia, cross-discipline science activities, curricula, and media programing. Audience reach, impact, and lessons learned are detailed. Plans for similar events in 2018 and beyond are outlined.

Systems definition space-based power conversion systems. [for satellite power transmission to earth

NASA Technical Reports Server (NTRS)

1976-01-01

Potential space-located systems for the generation of electrical power for use on Earth are discussed and include: (1) systems producing electrical power from solar energy; (2) systems producing electrical power from nuclear reactors; and (3) systems for augmenting ground-based solar power plants by orbital sunlight reflectors. Systems (1) and (2) would utilize a microwave beam system to transmit their output to Earth. Configurations implementing these concepts were developed through an optimization process intended to yield the lowest cost for each. A complete program was developed for each concept, identifying required production rates, quantities of launches, required facilities, etc. Each program was costed in order to provide the electric power cost appropriate to each concept.

Track membranes with open pores used as diffractive filters for space-based x-ray and EUV solar observations.

PubMed

Dominique, Marie; Mitrofanov, A V; Hochedez, J-F; Apel, P Yu; Schühle, U; Pudonin, F A; Orelovich, O L; Zuev, S Yu; Bolsée, D; Hermans, C; BenMoussa, A

2009-02-10

We describe the fabrication and performance of diffractive filters designed for space-based x-ray and EUV solar observations. Unlike traditional thin film filters, diffractive filters can be made to have a high resistance against the destructive mechanical and acoustic loads of a satellite launch. The filters studied are made of plastic track-etched membranes that are metal-coated on one side only. They have all-through open cylindrical pores with diameters as small as 500 nm, limiting their transmittance to very short wavelengths. The spectral transmittance of various diffractive filters with different pore parameters was measured from the soft x-ray to the near IR range (namely, from 1-1100 nm).

In-Space Propulsion Technologies for Robotic Exploration of the Solar System

NASA Technical Reports Server (NTRS)

Johnson, Les; Meyer, Rae Ann; Frame, Kyle

2006-01-01

Supporting NASA's Science Mission Directorate, the In-Space Propulsion Technology Program is developing the next generation of space propulsion technologies for robotic, deep-space exploration. Recent technological advancements and demonstrations of key, high-payoff propulsion technologies have been achieved and will be described. Technologies under development and test include aerocapture, solar electric propulsion, solar sail propulsion, and advanced chemical propulsion.

Ensemble downscaling in coupled solar wind-magnetosphere modeling for space weather forecasting.

PubMed

Owens, M J; Horbury, T S; Wicks, R T; McGregor, S L; Savani, N P; Xiong, M

2014-06-01

Advanced forecasting of space weather requires simulation of the whole Sun-to-Earth system, which necessitates driving magnetospheric models with the outputs from solar wind models. This presents a fundamental difficulty, as the magnetosphere is sensitive to both large-scale solar wind structures, which can be captured by solar wind models, and small-scale solar wind "noise," which is far below typical solar wind model resolution and results primarily from stochastic processes. Following similar approaches in terrestrial climate modeling, we propose statistical "downscaling" of solar wind model results prior to their use as input to a magnetospheric model. As magnetospheric response can be highly nonlinear, this is preferable to downscaling the results of magnetospheric modeling. To demonstrate the benefit of this approach, we first approximate solar wind model output by smoothing solar wind observations with an 8 h filter, then add small-scale structure back in through the addition of random noise with the observed spectral characteristics. Here we use a very simple parameterization of noise based upon the observed probability distribution functions of solar wind parameters, but more sophisticated methods will be developed in the future. An ensemble of results from the simple downscaling scheme are tested using a model-independent method and shown to add value to the magnetospheric forecast, both improving the best estimate and quantifying the uncertainty. We suggest a number of features desirable in an operational solar wind downscaling scheme. Solar wind models must be downscaled in order to drive magnetospheric models Ensemble downscaling is more effective than deterministic downscaling The magnetosphere responds nonlinearly to small-scale solar wind fluctuations.

Stochastic Short-term High-resolution Prediction of Solar Irradiance and Photovoltaic Power Output

DOE Office of Scientific and Technical Information (OSTI.GOV)

Melin, Alexander M.; Olama, Mohammed M.; Dong, Jin

The increased penetration of solar photovoltaic (PV) energy sources into electric grids has increased the need for accurate modeling and prediction of solar irradiance and power production. Existing modeling and prediction techniques focus on long-term low-resolution prediction over minutes to years. This paper examines the stochastic modeling and short-term high-resolution prediction of solar irradiance and PV power output. We propose a stochastic state-space model to characterize the behaviors of solar irradiance and PV power output. This prediction model is suitable for the development of optimal power controllers for PV sources. A filter-based expectation-maximization and Kalman filtering mechanism is employed tomore » estimate the parameters and states in the state-space model. The mechanism results in a finite dimensional filter which only uses the first and second order statistics. The structure of the scheme contributes to a direct prediction of the solar irradiance and PV power output without any linearization process or simplifying assumptions of the signal’s model. This enables the system to accurately predict small as well as large fluctuations of the solar signals. The mechanism is recursive allowing the solar irradiance and PV power to be predicted online from measurements. The mechanism is tested using solar irradiance and PV power measurement data collected locally in our lab.« less

Space Nuclear Power Systems

NASA Technical Reports Server (NTRS)

Houts, Michael G.

2012-01-01

Fission power and propulsion systems can enable exciting space exploration missions. These include bases on the moon and Mars; and the exploration, development, and utilization of the solar system. In the near-term, fission surface power systems could provide abundant, constant, cost-effective power anywhere on the surface of the Moon or Mars, independent of available sunlight. Affordable access to Mars, the asteroid belt, or other destinations could be provided by nuclear thermal rockets. In the further term, high performance fission power supplies could enable both extremely high power levels on planetary surfaces and fission electric propulsion vehicles for rapid, efficient cargo and crew transfer. Advanced fission propulsion systems could eventually allow routine access to the entire solar system. Fission systems could also enable the utilization of resources within the solar system.

Space station WP-04 power system. Volume 2: Study results

NASA Technical Reports Server (NTRS)

Hallinan, G. J.

1987-01-01

Results of the phase B study contract for the definition of the space station Electric Power System (EPS) are presented in detail along with backup information and supporting data. Systems analysis and trades, preliminary design, advanced development, customer accommodations, operations planning, product assurance, and design and development phase planning are addressed. The station design is a hybrid approach which provides user power of 25 kWe from the photovoltaic subsystem and 50 kWe from the solar dynamic subsystem. The electric power is distributed to users as a utility service; single phase at a frequency of 20 kHz and voltage of 440VAC. The solar array NiH2 batteries of the photovoltaic subsystem are based on commonality to those used on the co-orbiting and solar platforms.

Solar Radio Observation using Callisto Spectrometer at Sumedang West Java Indonesia: Current Status and Future Development Plan in Indonesia

NASA Astrophysics Data System (ADS)

Manik, T.; Sitompul, P.; Batubara, M.; Harjana, T.; Yatini, C. Y.; Monstein, C.

2016-04-01

Sumedang Observatory (6.91°S, 107,84°E) was established in 1975 and is one of the solar observation facilities of the Space Science Center of Indonesian National Institute of Aeronautics and Space (LAPAN), located around 40 km, east part of Bandung City, West Java, Indonesia. Several instrumentations for solar and space observation such as optical telescopes, radio solar spectrograph, flux gate magnetometer, etc. are operated there, together with an ionosphere sounding system (ionosonde) that was set up later. In July 2014, a standard Callisto (Compound Astronomical Low-cost Low-frequency Instrument for Spectroscopy and Transportable Observatory) spectrometer was installed at Sumedang Observatory for solar radio activity monitoring. Callisto has been developed in the framework of IHY2007 and ISWI, supported by UN and NASA. Callisto spectrometer has observation capability in the frequency range of 45-870 MHz. The Callisto spectrometer receives signal by using a set of 21 elements log-periodic antenna, model CLP5130-1N, pointed to the Sun and equipped with a low noise pre-amplifier. With respect to the Radio Frequency Interferences (RFI) measurements, the Callisto spectrometer is operated individually in frequency ranges of 45-80 MHz and 180-450 MHz. Observation status and data flow are monitored in on-line from center office located in Bandung. The data was transferred to central database at FHNW (Fachhochschule Nordwestschweiz) server every 15 minutes to appear on e-Callisto network subsequently. A real time data transfer and data processing based on Python software also has been developed successfully to be used as an input for Space Weather Information and Forecasting Services (SWIFtS) provided by LAPAN. On 5th November 2014, Callisto spectrometer at Sumedang observed the first clear solar radio event, a solar radio burst type II corresponding to a coronal mass ejection (CME), indicated by a strong X-ray event of M7.9 that was informed on by Space Weather Prediction Center (SWPC) NOAA. Thereafter, Callisto spectrometer at Sumedang also observed several solar radio bursts in various types. This paper describes the system configuration of Callisto spectrometer installed at Sumedang, RFI measurement and chosen observation strategy, real time data transfer and processing, as well as several samples of present results of solar radio burst monitoring at Sumedang, and future development plan of Callisto spectrometer in Indonesia which will be able to cover 14 hours of day solar observation. Keywords: Callisto spectrometer, solar radio observation, SWIFtS.

The Virtual Solar-Terrestrial Observatory; access to and use of diverse solar and solar- terrestrial data.

NASA Astrophysics Data System (ADS)

Fox, P.; McGuinness, D.; Cinquini, L.; West, P.; Garcia, J.; Zednik, S.; Benedict, J.

2008-05-01

This presentation will demonstrate how users and other data providers can utilize the Virtual Solar-Terrestrial Observatory (VSTO) to find, access and use diverse data holdings from the disciplines of solar, solar-terrestrial and space physics. VSTO provides a web portal, web services and a native applications programming interface for various levels of users. Since these access methods are based on semantic web technologies and refer to the VSTO ontology, users also have the option of taking advantage of value added services when accessing and using the data. We present example of both conventional use of VSTO as well as the advanced semantics use. Finally, we present our future directions for VSTO and semantic data frameworks in general.

The Virtual Solar-Terrestrial Observatory; access to and use of diverse solar and solar-terrestrial data

NASA Astrophysics Data System (ADS)

Fox, P.

2007-05-01

This presentation will demonstrate how users and other data providers can utilize the Virtual Solar-Terrestrial Observatory (VSTO) to find, access and use diverse data holdings from the disciplines of solar, solar-terrestrial and space physics. VSTO provides a web portal, web services and a native applications programming interface for various levels of users. Since these access methods are based on semantic web technologies and refer to the VSTO ontology, users also have the option of taking advantage of value added services when accessing and using the data. We present example of both conventional use of VSTO as well as the advanced semantics use. Finally, we present our future directions for VSTO and semantic data frameworks in general.

Solar cell array design handbook - The principles and technology of photovoltaic energy conversion

NASA Technical Reports Server (NTRS)

Rauschenbach, H. S.

1980-01-01

Photovoltaic solar cell array design and technology for ground-based and space applications are discussed from the user's point of view. Solar array systems are described, with attention given to array concepts, historical development, applications and performance, and the analysis of array characteristics, circuits, components, performance and reliability is examined. Aspects of solar cell array design considered include the design process, photovoltaic system and detailed array design, and the design of array thermal, radiation shielding and electromagnetic components. Attention is then given to the characteristics and design of the separate components of solar arrays, including the solar cells, optical elements and mechanical elements, and the fabrication, testing, environmental conditions and effects and material properties of arrays and their components are discussed.

Workshop on the Space Environment: The Effects on the Optical Properties of Airless Bodies

NASA Technical Reports Server (NTRS)

Hapke, B. (Editor); Clark, B. (Editor); Benedix, G. (Editor); Domingue, D. (Editor); Cintala, M. (Editor)

1993-01-01

Reflectance spectrophotometry and polarimetry are major tools in remote sensing studies of surfaces of solar system bodies. The interpretations of such measurements are often based on laboratory studies of meteoritic, lunar, and terrestrial materials. However, the optical properties of regoliths are known to be affected by the space environment. Thus, some of the major questions addressed in the workshop include identity of the soil component responsible for alteration of the optical properties, the process that produced this component, and how reliably the effects of these processes could be extrapolated to other bodies of the solar system.

Solar dynamic power for Earth orbital and lunar applications

NASA Technical Reports Server (NTRS)

Calogeras, James E.; Dustin, Miles O.; Secunde, Richard R.

1991-01-01

Development of solar dynamic (SD) technologies for space over the past 25 years by NASA Lewis Research Center brought SD power to the point where it was selected in the design phase of Space Station Freedom Program as the power source for evolutionary growth. More recent studies showed that large cost savings are possible in establishing manufacturing processes at a Lunar Base if SD is considered as a power source. Technology efforts over the past 5 years have made possible lighter, more durable, SD components for these applications. A review of these efforts and respective benefits is presented.

Development of optical modulators for measurements of solar magnetic fields

NASA Technical Reports Server (NTRS)

West, E. A.; Smith, J. E.

1987-01-01

The measurement of polarized light allows solar astronomers to infer the magnetic field on the Sun. The accuracy of these measurements is dependent on the stable retardation characteristics of the polarization modulators used to minimize the atmospheric effects seen in ground-based observations. This report describes the work by the Space Science Laboratory at Marshall Space Flight Center to improve two types of polarization modulators. As a result, the timing characteristics for both electrooptic crystals (KD*Ps) and liquid crystal devices (LCDs) have been studied and will be used to enhance the capabilities of the MSFC Vector Magnetograph.

Next generation of space based sensor for application in the SSA space weather domain.

NASA Astrophysics Data System (ADS)

Jansen, Frank; Kudela, Karel; Behrens, Joerg

Next generation of space based sensor for application in the SSA space weather domain. F. Jansen1, K. Kudela2, J. Behrens1 and NESTEC consortium3 1DLR, Bremen, Germany 2IEP SAS Kosice, Slovakia 3NESTEC consortium members (DLR Bremen, DESY Hamburg, MPS Katlenburg-Lindau, CTU Prague, University of Twente, IEP-SAS Kosice, UCL/MSSL, University of Manchester, University of Surrey, Hermanus Magnetic Observatory, North-West University Potchefsroom, University of Montreal) High energy solar and galactic cosmic rays have twofold importance for the SSA space weather domain. Cosmic rays have dangerous effects for space, air and ground based assets, but on the other side cosmic rays are direct measure tools for real time space weather warning. A review of space weather related SSA results from operating global cosmic ray networks (especially those by neutron monitors and by muon directional telescopes), its limitations and main questions to be solved, is presented. Especially those recent results, received in real time and with high temporal resolution, are reviewed and discussed. In addition the relevance of these monitors and telescopes in forecasting geomagnetic disturbances are checked. Based on this study result, a next generation of highly miniaturized hybrid silicon pixel device (Medipix sensor) will be described for the following, beyond state-of-the-art application: a SSA satellite for high energy solar and galactic cosmic ray spectrum measurement, with a space plasma environment data package and CME real time imaging by means of cosmic rays. All data management and processing will be carried out on the satellite in real time. Insofar a high reduction of data and transmission to ground station of finalized space weather relevant data and images are foreseen.

Earth-to-Geostationary Orbit Transportation for Space Solar Power System Development

NASA Technical Reports Server (NTRS)

Martin, James A.; Donahue, Benjamin B.; Lawrence, Schuyler C.; McClanahan, James A.; Carrington, Connie K. (Technical Monitor)

2000-01-01

Space solar power satellites have the potential to provide abundant quantities of electricity for use on Earth. One concept, the Sun Tower, can be assembled in geostationary orbit from pieces transferred from Earth. The cost of transportation is one of the major hurdles to space solar power. This study found that autonomous solar-electric transfer is a good choice for the transportation from LEO to GEO.

Space Science

NASA Image and Video Library

1990-10-01

Using the Solar Vector Magnetograph, a solar observation facility at NASA's Marshall Space Flight Center (MSFC), scientists from the National Space Science and Technology Center (NSSTC) in Huntsville, Alabama, are monitoring the explosive potential of magnetic areas of the Sun. This effort could someday lead to better prediction of severe space weather, a phenomenon that occurs when blasts of particles and magnetic fields from the Sun impact the magnetosphere, the magnetic bubble around the Earth. When massive solar explosions, known as coronal mass ejections, blast through the Sun's outer atmosphere and plow toward Earth at speeds of thousands of miles per second, the resulting effects can be harmful to communication satellites and astronauts outside the Earth's magnetosphere. Like severe weather on Earth, severe space weather can be costly. On the ground, the magnetic storm wrought by these solar particles can knock out electric power. The researchers from MSFC and NSSTC's solar physics group develop instruments for measuring magnetic fields on the Sun. With these instruments, the group studies the origin, structure, and evolution of the solar magnetic field and the impact it has on Earth's space environment. This photograph shows the Solar Vector Magnetograph and Dr. Mona Hagyard of MSFC, the director of the observatory who leads the development, operation and research program of the Solar Vector Magnetograph.

2-kW Solar Dynamic Space Power System Tested in Lewis' Thermal Vacuum Facility

NASA Technical Reports Server (NTRS)

1995-01-01

Working together, a NASA/industry team successfully operated and tested a complete solar dynamic space power system in a large thermal vacuum facility with a simulated sun. This NASA Lewis Research Center facility, known as Tank 6 in building 301, accurately simulates the temperatures, high vacuum, and solar flux encountered in low-Earth orbit. The solar dynamic space power system shown in the photo in the Lewis facility, includes the solar concentrator and the solar receiver with thermal energy storage integrated with the power conversion unit. Initial testing in December 1994 resulted in the world's first operation of an integrated solar dynamic system in a relevant environment.

Investigation of Teflon FEP Embrittlement on Spacecraft in Low Earth Orbit

NASA Technical Reports Server (NTRS)

deGroh, Kim K.; Smith, Daniela C.

1997-01-01

Teflon(registered trademark) FEP (fluorinated ethylene-propylene) is commonly used on exterior spacecraft surfaces in the low Earth orbit (LEO) environment for thermal control. Silverized or aluminized FEP is used for the outer layer of thermal control blankets because of its low solar absorptance and high thermal emittance. FEP is also preferred over other spacecraft polymers because of its relatively high resistance to atomic oxygen erosion. Because of its low atomic oxygen erosion yield, FEP has not been protected in the space environment. Recent, long term space exposures such as on the Long Duration Exposure Facility (LDEF, 5.8 years in space), and the Hubble Space Telescope (HST, after 3.6 years in space) have provided evidence of LEO environmental degradation of FEP. These exposures provide unique opportunities for studying environmental degradation because of the long durations and the different conditions (such as differences in altitude) of the exposures. Samples of FEP from LDEF and from HST (retrieved during its first servicing mission) have been evaluated for solar induced embrittlement and for synergistic effects of solar degradation and atomic oxygen. Micro-indenter results indicate that the surface hardness increased as the ratio of atomic oxygen fluence to solar fluence decreased for the LDEF samples. FEP multilayer insulation (MLI) retrieved from HST provided evidence of severe embrittlement on solar facing surfaces. Micro-indenter measurements indicated higher surface hardness values for these samples than LDEF samples, but the solar exposures were higher. Cracks induced during bend testing were significantly deeper for the HST samples with the highest solar exposure than for LDEF samples with similar atomic oxygen fluence to solar fluence ratios. If solar fluences are compared, the LDEF samples appear as damaged as HST samples, except that HST had deeper induced cracks. The results illustrate difficulties in comparing LEO exposed materials from different missions. Because the HST FEP appears more damaged than LDEF FEP based on depth of embrittlement, other causes for FEP embrittlement in addition to atomic oxygen and ultraviolet (UV) radiation, such as thermal effects and the possible role of soft x-ray radiation, need to be considered. FEP that was exposed to soft x-rays in a ground test facility, showed embrittlement similar to that witnessed in LEO, which indicates that the observed differences between LDEF and HST FEP might be attributed to the different soft x-ray fluences during these two missions.

A Forecast of Reduced Solar Activity and Its Implications for NASA

NASA Technical Reports Server (NTRS)

Schatten, Kenneth; Franz, Heather

2005-01-01

The "Solar Dynamo" method of solar activity forecasting is reviewed. Known generically as a 'precursor" method, insofar as it uses observations which precede solar activity generation, this method now uses the Solar Dynamo Amplitude (SODA) Index to estimate future long-term solar activity. The peak amplitude of the next solar cycle (#24), is estimated at roughly 124 in terms of smoothed F10.7 Radio Flux and 74 in terms of the older, more traditional smoothed international or Zurich Sunspot number (Ri or Rz). These values are significantly smaller than the amplitudes of recent solar cycles. Levels of activity stay large for about four years near the peak in smoothed activity, which is estimated to occur near the 2012 timeflame. Confidence is added to the prediction of low activity by numerous examinations of the Sun s weakened polar field. Direct measurements are obtained by the Mount Wilson Solar Observatory and the Wilcox Solar Observatory. Further support is obtained by examining the Sun s polar faculae (bright features), the shape of coronal soft X-ray "holes," and the shape of the "source surface" - a calculated coronal feature which maps the large scale structure of the Sun s field. These features do not show the characteristics of well-formed polar coronal holes associated with typical solar minima. They show stunted polar field levels, which are thought to result in stunted levels of solar activity during solar cycle #24. The reduced levels of solar activity would have concomitant effects upon the space environment in which satellites orbit. In particular, the largest influences would affect orbit determination of satellites in LEO (Low Earth Orbit), based upon the altered thermospheric and exospheric densities. A decrease in solar activity would result in smaller satellite decay rates, as well as fewer large solar events that can destroy satellite electronic functions. Other effects of reduced solar activity upon the space environment include enhanced galactic cosmic rays and more space debris at low altitudes (from the decay of old satellite parts, etc.). The reasons are well known: namely, solar activity serves to sweep the inner heliosphere of galactic cosmic rays, and lower exospheric densities result in decreased drag on LEO debris, allowing longer lifetimes.

Deployable Propulsion, Power and Communication Systems for Solar System Exploration

NASA Technical Reports Server (NTRS)

Johnson, Les; Carr, John A.; Boyd, Darren

2017-01-01

NASA is developing thin-film based, deployable propulsion, power, and communication systems for small spacecraft that could provide a revolutionary new capability allowing small spacecraft exploration of the solar system. By leveraging recent advancements in thin films, photovoltaics, and miniaturized electronics, new mission-level capabilities will be enabled aboard lower-cost small spacecraft instead of their more expensive, traditional counterparts, enabling a new generation of frequent, inexpensive deep space missions. Specifically, thin-film technologies are allowing the development and use of solar sails for propulsion, small, lightweight photovoltaics for power, and omnidirectional antennas for communication. Like their name implies, solar sails 'sail' by reflecting sunlight from a large, lightweight reflective material that resembles the sails of 17th and 18th century ships and modern sloops. Instead of wind, the sail and the ship derive their thrust by reflecting solar photons. Solar sail technology has been discussed in the literature for quite some time, but it is only since 2010 that sails have been proven to work in space. Thin-film photovoltaics are revolutionizing the terrestrial power generation market and have been found to be suitable for medium-term use in the space environment. When mounted on the thin-film substrate, these photovoltaics can be packaged into very small volumes and used to generate significant power for small spacecraft. Finally, embedded antennas are being developed that can be adhered to thin-film substrates to provide lightweight, omnidirectional UHF and X-band coverage, increasing bandwidth or effective communication ranges for small spacecraft. Taken together, they may enable a host of new deep space destinations to be reached by a generation of spacecraft smaller and more capable than ever before.

Complexity of the Earth's space-atmosphere interaction region (SAIR) response to the solar flux at 10.7 cm as seen through the evaluation of five solar cycle two-line element (TLE) records

NASA Astrophysics Data System (ADS)

Molaverdikhani, Karan; Ajabshirizadeh, Ali; Davoudifar, Pantea; Lashkanpour, Majid

2016-09-01

Orbital debris are long-standing threats to space systems. They also contribute to the flux of macroscopic particles into the Earth's atmosphere and eventually affects environmental processes across several other related regions. As impactful space debris may be, debris along with other Low Earth Orbit (LEO) orbiting objects, also serve as valuable long-monitoring probes to deduce the properties of geospace environment in-situ. We define the Daily Decay Rate (DDR) as a suitable indicator of how the Earth's space-atmosphere interaction region (SAIR) responds to solar activity and how solar activity directly affects the orbital evolution of a LEO orbiter. We present a computationally simplified technique that simultaneously solves the motion equations for DDR and cross-sectional area to mass ratio (A/m) from consecutive TLE records. By evaluating more than 50 million TLE records we estimate A/m of 15,307 NORAD-indexed objects and determine how DDR varies. We observe the thermospheric ;natural thermostat; in our results, consistent with previous studies. We compare the observed DDRs with two models based on NRLMSISE-00 and DTM-2013, and present evidence the models display a systemic altitudinal bias. We propose several possibilities to explain this altitudinal bias including the overestimated CD at low altitudes in our models (presumably due to the despinning effect of perturbing forces on the orbiting objects), and incomplete and limited coverage of in-situ observations at high solar activity. We conclude that the density models do not reliably reproduce the densities and atmospheric-thermospheric behaviors at high solar active conditions, especially for F10.7 cm above 300 sfu.

The International Solar Terrestrial Physics Program: A Model for International Cooperation in Space Research

NASA Astrophysics Data System (ADS)

Acuña, M.

The International Solar Terrestrial Physics Program (ISTP) evolved from the individual plans of US, Japanese and European countries to develop space missions to expand our knowledge of the Sun-Earth connection as a "system". Previous experience with independent missions amply illustrated the critical need for coordinated and simultaneous observations in key regions of Sun-Earth space in order to resolve time-space ambiguities and cause-effect relationships. Mission studies such as the US Origins of Plasmas in the Earth's Neighborhood (OPEN), Geotail in Japan, the Solar Heliospheric Observatory in Europe and the Regatta and other magnetospheric missions in the former Soviert Union, formed the early conceptual elements that eventually led to the ISTP program. The coordinating role developed by the Inter-Agency-Consultative-Group (IACG) integrated by NASA, ESA, ISAS and IKI and demonstrated during the comet Halley apparition in 1986, was continued to include solar-terrestrial research and the mission elements described above. In addition to the space elements, a most important component of the coordination effort was the inclusion of data networks, analysis and planning tools as well as globally accessible data sets by the scientific community at large. This approach enabled the active and direct participation of scientists in developing countries in one of the most comprehensive solar-terrestrial research programs implemented to date. The creation of multiple ISTP data repositories throughout the world has enabled a large number of scientists in developing countries to have direct access to the latest spacecraft observations and a most fruitful interaction with fellow researchers throughout the world. This paper will present a review of the evolution of the ISTP program, its products, analysis tools, data bases, infrastructure and lessons learned applicable to future international collaborative programs.

The development of a solar-powered residential heating and cooling system

NASA Technical Reports Server (NTRS)

1974-01-01

Efforts to demonstrate the engineering feasibility of utilizing solar power for residential heating and cooling are described. These efforts were concentrated on the analysis, design, and test of a full-scale demonstration system which is currently under construction at the National Aeronautics and Space Administration, Marshall Space Flight Center, Huntsville, Alabama. The basic solar heating and cooling system under development utilizes a flat plate solar energy collector, a large water tank for thermal energy storage, heat exchangers for space heating and water heating, and an absorption cycle air conditioner for space cooling.

Support and maneuvering apparatus for solar energy receivers

DOEpatents

Murphy, L.M.

1988-07-28

A support and maneuvering apparatus is disclosed for a solar energy receiving device adapted for receiving and concentrating solar energy and having a central axis extending through the center thereof. The apparatus includes a frame for mounting the perimeter of said solar energy receiving device. A support member extends along the central axis of the receiving device and has a base end passing through the center of the receiving device and an outer distal end adapted for carrying a solar energy receiving and conversion mechanism. A variable tension mechanism interconnects the support member with the frame to provide stiffening for the support member and the frame and to assist in the alignment of the frame to optimize the optical efficiency of the solar energy receiving device. A rotatable base is provided, and connecting members extend from the base for pivotable attachment to the frame at spaced positions therealong. Finally, an elevation assembly is connected to the receiving device for selectively pivoting the receiving about an axis defined between the attachment positions of the connecting members on the frame. 4 figs.

Support and maneuvering apparatus for solar energy receivers

DOEpatents

Murphy, Lawrence M.

1989-01-01

A support and maneuvering apparatus is disclosed for a solar energy receiving device adpated for receiving and concentrating solar energy and having a central axis extending through the center thereof. The apparatus includes a frame for mounting the perimeter of said solar energy receiving device. A support member extends along the central axis of the receiving device and has a base end passing through the center of the receiving device and an outer distal end adapted for carrying a solar energy receiving and conversion mechanism. A variable tension mechanism interconnects the support member with the frame to provide stiffening for the support member and the frame and to assist in the alignment of the frame to optimize the optical efficiency of the solar energy receiving device. A rotatable base is provided, and connecting members extend from the base for pivotable attachment to the frame at spaced positions therealong. Finally, an elevation assembly is connected to the receiving device for selectively pivoting the receiving device about an axis defined between the attachment positions of the connecting members on the frame.

Current Status of Study on Hydrogen Production with Space Solar Power Systems (SSPS)

NASA Astrophysics Data System (ADS)

Mori, M.; Kagawa, H.; Nagayama, H.; Saito, Y.

2004-12-01

Japan Aerospace Exploration Agency (JAXA) has been conducting studies on Space Solar Power Systems (SSPS) using microwave and laser beams for years since FY1998 organizing a special committee and working groups. The microwave based SSPS are huge solar power systems that generate GW power by solar cells. The electric power is transmitted via microwave from the SSPS to the ground. In the laser based SSPS, a solar condenser equipped with lenses or mirrors and laser-generator would be put into orbit. A laser beam would be sent to Earth-based hydrogen generating device. We are proposing a roadmap that consists of a stepwise approach to achieve commercial SSPS in 20-30 years. The first step is 50kW class Technology Demonstration Satellite to demonstrate microwave power transmission. The second step is to demonstrate robotic assembly of 10MW class large scale flexible structure in space on ISS co-orbit. The third step is to build a prototype SSPS in GEO. The final step is to build commercial SSPS in GEO. We continue the study of SSPS concepts and architectures, technology flight demonstration and major technology development. System design of tens of kW class Technology Demonstration Satellite and conceptual study of 10MW class demonstration system on ISS co-orbit are also conducted. Several key technologies which are needed to be developed in appropriate R&D roadmap, such as high-voltage solar cell array, fiber type of direct solar pumping solid-state laser, high efficiency magnetron, thermal control technology and control technology of large scale flexible structure etc. are also investigated. In the study of concept design of commercial SSPS mentioned above, we have studied some configurations of both microwave based SSPS and laser based SSPS. In case of microwave based SSPS, the solar energy must be converted to electricity and then converted to a microwave beam. The on-ground rectifying antenna will collect the microwave beam and convert it to electricity to connect to commercial power grids. From the past experiences of the conceptual design of the1GW class SSPS, it is clear that system with the mirrors and modularized unit which integrated solar cells and microwave power transmitters is promising. In this type of SSPS, the solar lights are directed to the energy conversion unit integrated solar cells and microwave power transmitters using mirrors. The key factor in designing systems is feasibility of thermal system. Considering above these factors, some reference models are being considered now. FY2003 reference model is the model for formation flight without the center truss which connect to primary mirrors to energy conversion unit. Using this model as basis, we are carrying out examination from various viewpoints aiming at the cost minimum to build and maintain the systems. In case of laser based SSPS, the laser beam would be directly produced from the solar light using the direct solar pumping solid-state laser device. This laser beams would be collected on ground and used to produce hydrogen from seawater. The receiving / energy conversion station is settled on an ocean, and producing hydrogen can be stored and transported by ships to consumers. In designing laser based SSPS, conversion efficiency of the direct solar pumping solid-state laser and feasibility of thermal system are critical factors. Since magnification of solar concentrator is very high, improvement of thermal control system is important. Feasibility of its ground facilities and production technology of hydrogen using laser beams has been also studied. Both hydrogen generating systems with photo-catalyst device and electrolytic ones have been examined. From the past experiences of this study, high efficient electric power generating technology using the solar cell which suited the wavelength of laser is promising. The life cycle cost model of laser based SSPS was created and evaluated its validity. Sensitivity analysis of laser based SSPS are also continued aiming at hydrogen generating cost of around 20 cent per Nm3 . This paper presents a summary of studies on SSPS that JAXA has examined.

Space Station Freedom Solar Array design development

NASA Technical Reports Server (NTRS)

Winslow, Cindy; Bilger, Kevin; Baraona, Cosmo R.

1989-01-01

The Space Station Freedom Solar Array Program is required to provide a 75 kW power module that uses eight solar array (SA) wings over a four-year period in low Earth orbit (LEO). Each wing will be capable of providing 23.4 kW at the 4-year design point. Lockheed Missles and Space Company, Inc. (LMSC) is providing the flexible substrate SAs that must survive exposure to the space environment, including atomic oxygen, for an operating life of fifteen years. Trade studies and development testing, important for evolving any design to maturity, are presently underway at LMSC on the flexible solar array. The trade study and development areas being investigated include solar cell module size, solar cell weld pads, panel stiffener frames, materials inherently resistant to atomic oxygen, and weight reduction design alternatives.

Climate responses to SATIRE and SIM-based spectral solar forcing in a 3D atmosphere-ocean coupled GCM

NASA Astrophysics Data System (ADS)

Wen, Guoyong; Cahalan, Robert F.; Rind, David; Jonas, Jeffrey; Pilewskie, Peter; Wu, Dong L.; Krivova, Natalie A.

2017-03-01

We apply two reconstructed spectral solar forcing scenarios, one SIM (Spectral Irradiance Monitor) based, the other the SATIRE (Spectral And Total Irradiance REconstruction) modeled, as inputs to the GISS (Goddard Institute for Space Studies) GCMAM (Global Climate Middle Atmosphere Model) to examine climate responses on decadal to centennial time scales, focusing on quantifying the difference of climate response between the two solar forcing scenarios. We run the GCMAM for about 400 years with present day trace gas and aerosol for the two solar forcing inputs. We find that the SIM-based solar forcing induces much larger long-term response and 11-year variation in global averaged stratospheric temperature and column ozone. We find significant decreasing trends of planetary albedo for both forcing scenarios in the 400-year model runs. However the mechanisms for the decrease are very different. For SATIRE solar forcing, the decreasing trend of planetary albedo is associated with changes in cloud cover. For SIM-based solar forcing, without significant change in cloud cover on centennial and longer time scales, the apparent decreasing trend of planetary albedo is mainly due to out-of-phase variation in shortwave radiative forcing proxy (downwelling flux for wavelength >330 nm) and total solar irradiance (TSI). From the Maunder Minimum to present, global averaged annual mean surface air temperature has a response of 0.1 °C to SATIRE solar forcing compared to 0.04 °C to SIM-based solar forcing. For 11-year solar cycle, the global surface air temperature response has 3-year lagged response to either forcing scenario. The global surface air 11-year temperature response to SATIRE forcing is about 0.12 °C, similar to recent multi-model estimates, and comparable to the observational-based evidence. However, the global surface air temperature response to 11-year SIM-based solar forcing is insignificant and inconsistent with observation-based evidence.

Relation between the electromagnetic processes in the near-Earth space and dynamics of the biological resources in Russian Arctic

NASA Astrophysics Data System (ADS)

Makarova, L. N.; Shirochkov, A. V.; Tumanov, I. L.

The start of the satellite era in the Space explorations led to new and more profound knowledge of the solar physics and the sources of its activity. From these points of view, it is worthy to examine again the relations between biological processes and the solar activity. We explore the relation between dynamics of the solar activity (including the solar wind) and changes in population of some species of Arctic fauna (lemmings, polar foxes, caribous, wolves, elks, etc.). The data include statistical rows of various lengths (30 80 years). The best correlation between two data sets is found when the solar wind dynamic pressure as well as variations of the total solar irradiance (i.e., level of the solar UV radiation) is taken as the space parameters. Probably the electromagnetic fields of space origin are an important factor determining dynamics of population of the Arctic fauna species.

Electrochemical Characterization of InP and GaAs Based Structures for Space Solar Cell Applications.

NASA Technical Reports Server (NTRS)

Faur, Maria; Faur, Mircea; Jenkins, Philip P.; Goradia, Manju; Wilt, David M.

1994-01-01

In this paper the emphasis is on accurate majority carrier concentration EC-V profiling of structures based on Indium Phosphide and Gallium Arsenide, using a newly developed electrolyte based on Hydrogen Flouride, Acetic Acid, Phosphoric Acid, 1-phenyl-2-propanamine and Ammonia Diflouride. Some preliminary data on the use of this electrolyte for determining the energy distribution of surface and deep states of these structures, applicable to fabrication process optimization and radiation induced defects studies of solar cells, are also provided.

The SOLAR-C Mission: Science Objectives and Current Status

NASA Astrophysics Data System (ADS)

Suematsu, Y.; Solar-C Working Group

2016-04-01

The SOLAR-C is a Japan-led international solar mission for mid-2020s designed to investigate the magnetic activities of the Sun, focusing on the study in heating and dynamical phenomena of the chromosphere and corona, and to advance algorithms for predicting short and long term solar magnetic activities. For these purposes, SOLAR-C will carry three dedicated instruments; the Solar UV-Vis-IR Telescope (SUVIT), the EUV Spectroscopic Telescope (EUVST) and the High Resolution Coronal Imager (HCI), to jointly observe the entire visible solar atmosphere with essentially the same high spatial resolution (0.1"-0.3"), performing high resolution spectroscopic measurements over all atmospheric regions and spectro-polarimetric measurements from the photosphere through the upper chromosphere. SOLAR-C will also contribute to understand the solar influence on the Sun-Earth environments with synergetic wide-field observations from ground-based and other space missions.

Radiation Physics for Space and High Altitude Air Travel

NASA Technical Reports Server (NTRS)

Cucinotta, F. A.; Wilson, J. W.; Goldhagen, P.; Saganti, P.; Shavers, M. R.; McKay, Gordon A. (Technical Monitor)

2000-01-01

Galactic cosmic rays (GCR) are of extra-solar origin consisting of high-energy hydrogen, helium, and heavy ions. The GCR are modified by physical processes as they traverse through the solar system, spacecraft shielding, atmospheres, and tissues producing copious amounts of secondary radiation including fragmentation products, neutrons, mesons, and muons. We discuss physical models and measurements relevant for estimating biological risks in space and high-altitude air travel. Ambient and internal spacecraft computational models for the International Space Station and a Mars mission are discussed. Risk assessment is traditionally based on linear addition of components. We discuss alternative models that include stochastic treatments of columnar damage by heavy ion tracks and multi-cellular damage following nuclear fragmentation in tissue.

Design challenges and methodology for developing new integrated circuits for the robotics exploration of the solar system

NASA Technical Reports Server (NTRS)

Mojarradi, Mohammad M.; Kolawa, Elizabeth; Blalock, Benjamin; Johnson, R. Wayne

2005-01-01

Next generation space-based robotics systems will be constructed using distributed architectures where electronics capable of working in the extreme environments of the planets of the solar system are integrated with the sensors and actuators in plug-and-play modules and are connected through common multiple redundant data and power buses.

Space manufacturing in the construction of solar power satellites

NASA Astrophysics Data System (ADS)

Ruth, J.; Westphal, W.

This paper deals with ongoing research work concerning energy budget and cost of the solar Satellite Power System (SPS). The fundamental model of such a total system including ground and space facilities, transportation vehicles, power satellites and rectennas is presented. The main purpose of this model is to examine the applicability of different construction scenarios to allow comparison under nearly identical constraints. Using this model in a first attempt the blankets—meaning the main part of the space segment by weight, energy investment needs and cost—are chosen representatively for the energy and cost comparison of two construction alternatives of the same SPS concept. These construction alternatives are defined just by ground and space based manufacturing of the solar blankets, while all other subsystems, operations and the transportation profiles are considered to be kept the same. It can be shown that the energy "payback" time does not only depend on the SPS concept selected but also very much on the construction and implementation scenario. The cost comparison of these alternative approaches presents not very significant differences but advantages for the space manufacturing option with potential higher differences for a less conservative approach which may apply benefits of space manufacturing meaning, for example, considerable mass savings in space. Some preliminary results are discussed and an outlook is given over the next steps to be investigated, comprising the extension of the fundamental model to include use of lunar raw materials.

NASA Solar Sail Propulsion Technology Development

NASA Technical Reports Server (NTRS)

Johnson, Les; Montgomery, Edward E.; Young, Roy; Adams, Charles

2007-01-01

NASA's In-Space Propulsion Technology Program has developed the first generation of solar sail propulsion systems sufficient to accomplish inner solar system science and exploration missions. These first generation solar sails, when operational, will range in size from 40 meters to well over 100 meters in diameter and have an areal density of less than 13 grams per square meter. A rigorous, multi-year technology development effort culminated in 2005 with the testing of two different 20-m solar sail systems under thermal vacuum conditions. The first system, developed by ATK Space Systems of Goleta, California, uses rigid booms to deploy and stabilize the sail. In the second approach, L'Garde, Inc. of Tustin, California uses inflatable booms that rigidize in the coldness of space to accomplish sail deployment. This effort provided a number of significant insights into the optimal design and expected performance of solar sails as well as an understanding of the methods and costs of building and using them. In a separate effort, solar sail orbital analysis tools for mission design were developed and tested. Laboratory simulations of the effects of long-term space radiation exposure were also conducted on two candidate solar sail materials. Detailed radiation and charging environments were defined for mission trajectories outside the protection of the earth's magnetosphere, in the solar wind environment. These were used in other analytical tools to prove the adequacy of sail design features for accommodating the harsh space environment. Preceding and in conjunction with these technology efforts, NASA sponsored several mission application studies for solar sails. Potential missions include those that would be flown in the near term to study the sun and be used in space weather prediction to one that would use an evolved sail capability to support humanity's first mission into nearby interstellar space. This paper will describe the status of solar sail propulsion within NASA, nearterm solar sail mission applications, and near-term plans for further development.

Space Science

NASA Image and Video Library

2002-04-01

Using the Solar Vector Magnetograph, a solar observation facility at NASA's Marshall Space Flight Center (MSFC), scientists from the National Space Science and Technology Center (NSSTC) in Huntsville, Alabama, are monitoring the explosive potential of magnetic areas of the Sun. This effort could someday lead to better prediction of severe space weather, a phenomenon that occurs when blasts of particles and magnetic fields from the Sun impact the magnetosphere, the magnetic bubble around the Earth. When massive solar explosions, known as coronal mass ejections, blast through the Sun's outer atmosphere and plow toward Earth at speeds of thousands of miles per second, the resulting effects can be harmful to communication satellites and astronauts outside the Earth's magnetosphere. Like severe weather on Earth, severe space weather can be costly. On the ground, magnetic storms wrought by these solar particles can knock out electric power. Photographed are a group of contributing researchers in front of the Solar Vector Magnetograph at MSFC. The researchers are part of NSSTC's solar physics group, which develops instruments for measuring magnetic fields on the Sun. With these instruments, the group studies the origin, structure, and evolution of the solar magnetic fields and the impact they have on Earth's space environment.

Space Solar Power Program. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arif, Humayun; Barbosa, Hugo; Bardet, Christophe

1992-08-01

Information pertaining to the Space Solar Power Program is presented on energy analysis; markets; overall development plan; organizational plan; environmental and safety issues; power systems; space transportation; space manufacturing, construction, operations; design examples; and finance.

Working with NASA's OSS E/PO Support Network

NASA Astrophysics Data System (ADS)

Miner, E. D.; Lowes, L. L.

2001-11-01

With greater and greater emphasis on the inclusion of a public engagement component in all government-supported research funding, many members of the DPS are finding it difficult to find sufficient time and funding to develop a wide-reaching and effective E/PO program. NASA's Office of Space Science, over the last five years, has built a Support Network to assist its funded scientists to establish partnerships with local and/or national science formal or informal education organizations, who are anxious to connect with and use the expertise of space scientists. The OSS Support Network consists of four theme-based 'Forums,' including the Solar System Exploration (SSE) Forum, specifically designed for working with planetary scientists, and seven regional 'Brokers-Facilitators' who are more familiar with partnership and other potential avenues for involvement by scientists. The services provided by the Support Network are free to both the scientists and their potential partners and is not limited to NASA-funded scientists. In addition to its assistance to space scientists, the Support Network is involved in a number of other overarching efforts, including support of a Solar System Ambassador Program, a Solar System Educator Program, Space Place (web and e-mail science products for libraries and small planetariums and museums), an on-line Space Science Resource Directory, annual reports of Space Science E/PO activity, identifying and filling in 'holes' and 'over-populations' in a solar system E/PO product matrix of grade level versus product versus content, research on product effectiveness, and scientific and educational evaluation of space science products. Forum and Broker-Facilitator contact information is available at http://spacescience.nasa.gov/education/resources/ecosystem/index.htm. Handouts with additional information will be available at the meeting.

The solar flare myth

NASA Technical Reports Server (NTRS)

Gosling, J. T.

1993-01-01

Many years of research have demonstrated that large, nonrecurrent geomagnetic storms, shock wave disturbances in the solar wind, and energetic particle events in interplanetary space often occur in close association with large solar flares. This result has led to a pradigm of cause and effect - that large solar flares are the fundamental cause of these events in the near-Earth space environmemt. This paradigm, which I call 'the solar flare myth,' dominates the popular perception of the relationship between solar activity and interplanetary and geomagnetic events and has provided much of the pragmatic rationale for the study of the solar flare phenomenon. Yet there is good evidence that this paradigm is wrong and that flares do not generally play a central role in producing major transient disturbances in the near-Earth space environment. In this paper I outline a different paradigm of cause and effect that removes solar flares from their central position in the chain of events leading from the Sun to near-Earth space. Instead, this central role is given to events known as coronal mass ejections.

Lunar Swirls: Plasma Magnetic Field Interaction and Dust Transport

NASA Astrophysics Data System (ADS)

Dropmann, Michael; Laufer, Rene; Herdrich, Georg; Matthews, Lorin; Hyde, Truell

2013-10-01

In close collaboration between the Center for Astrophysics, Space Physics and Engineering Research (CASPER) at Baylor University, Texas, and the Institute of Space Systems (IRS) at the University of Stuttgart, Germany, two plasma facilities have been established using the Inductively heated Plasma Generator 6 (IPG6), based on proven IRS designs. A wide range of applications is currently under consideration for both test and research facilities. Basic investigations in the area of plasma radiation and catalysis, simulation of certain parameters of fusion divertors and space applications are planned. In this paper, the facility at Baylor University (IPG6-B) will be used for simulation of mini-magnetospheres on the Moon. The interaction of the solar wind with magnetic fields leads to the formation of electric fields, which can influence the incoming solar wind ion flux and affect dust transport processes on the lunar surface. Both effects may be partially responsible for the occurrence of lunar swirls. Interactions of the solar wind with such mini-magnetospheres will be simulated in the IPG6-B by observing the interaction between a plasma jet and a permanent magnet. The resulting data should lead to better models of dust transport processes and solar wind deflection on the moon.

Monitoring solar energetic particles with an armada of European spacecraft and the new automated SEPF (Solar Energetic Proton Fluxes) Tool

NASA Astrophysics Data System (ADS)

Sandberg, I.; Daglis, I. A.; Anastasiadis, A.; Balasis, G.; Georgoulis, M.; Nieminen, P.; Evans, H.; Daly, E.

2012-01-01

Solar energetic particles (SEPs) observed in interplanetary medium consist of electrons, protons, alpha particles and heavier ions (up to Fe), with energies from dozens of keVs to a few GeVs. SEP events, or SEPEs, are particle flux enhancements from background level (< 1 pfu, particle flux unit = particle cm-2sr-1s-1) to several orders of magnitude in the MeV range, and lasting from several hours to a few days. Intense SEPEs can reach fluence values as high as 1010 protons cm-2 for E > 30 MeV. The main part of SEPEs results from the acceleration of particles either by solar flares and/or by interplanetary shocks driven by Coronal Mass Ejections (CMEs); these accelerated particles propagate through the heliosphere, traveling along the interplanetary magnetic field (IMF). SEPEs show significant variability from one event to another and are an important part of space weather, because they pose a serious health risk to humans in space and a serious radiation hazard for the spacecraft hardware which may lead to severe damages. As a consequence, engineering models, observations and theoretical investigations related to the high energy particle environment is a priority issue for both robotic and manned space missions. The European Space Agency operates the Standard Radiation Environment Monitor (SREM) on-board six spacecraft: Proba-1, INTEGRAL, Rosetta, Giove-B, Herschel and Planck, which measures high-energy protons and electrons with a fair angular and spectral resolution. The fact that several SREM units operate in different orbits provides a unique chance for comparative studies of the radiation environment based on multiple data gathered by identical detectors. Furthermore, the radiation environment monitoring by the SREM unit onboard Rosetta may reveal unknown characteristics of SEPEs properties given the fact that the majority of the available radiation data and models only refer to 1AU solar distances. The Institute for Space Applications and Remote Sensing of the National Observatory of Athens (ISARS/NOA) has developed and validated a novel method to obtain flux spectra from SREM count rates. Using this method and by conducting detailed scientific studies we have showed in previous presentations and papers that the exploration and analysis of SREM data may contribute significantly to investigations and modeling efforts of SPE generation and propagation in the heliosphere and in the Earth's magnetosphere. ISARS/NOA recently released an automated software tool for the monitoring of Solar Energetic Proton Fluxes (SEPF) using measurements of SREM. The SEPF tool is based on the automated implementation of the inverse method developed by ISARS/NOA, permitting the calculation of high-energy proton fluxes from SREM data. Results of the method have been validated for selected number of past solar energetic particle events using measurements from other space-born proton monitors. The SEPF tool unfolds downlinked SREM count-rates, calculates the omnidirectional differential proton fluxes and provides results to the space weather community acting as a multi-point proton flux monitor on a daily-basis. The SEPF tool is a significant European space weather asset and will support the efforts towards an efficient European Space Situational Awareness programme.

Radiation and Internal Charging Environments for Thin Dielectrics in Interplanetary Space

NASA Technical Reports Server (NTRS)

Minow, Joseph I.; Parker, Linda Neergaard; Altstatt, Richard L.

2004-01-01

Spacecraft designs using solar sails for propulsion or thin membranes to shade instruments from the sun to achieve cryogenic operating temperatures are being considered for a number of missions in the next decades. A common feature of these designs are thin dielectric materials that will be exposed to the solar wind, solar energetic particle events, and the distant magnetotail plasma environments encountered by spacecraft in orbit about the Earth-Sun L2 point. This paper will discuss the relevant radiation and internal charging environments developed to support spacecraft design for both total dose radiation effects as well as dose rate dependent phenomenon, such as internal charging in the solar wind and distant magnetotail environments. We will describe the development of radiation and internal charging environment models based on nearly a complete solar cycle of Ulysses solar wind plasma measurements over a complete range of heliocentric latitudes and the early years of the Geotail mission where distant magnetotail plasma environments were sampled beyond X(sub GSE) = -100 Re to nearly L2 (X(sub GSE) -236 Re). Example applications of the environment models are shown to demonstrate the radiation and internal charging environments of thin materials exposed to the interplanetary space plasma environments.

Analysis of Direct Solar Illumination on the Backside of Space Station Solar Cells

NASA Technical Reports Server (NTRS)

Delleur, Ann M.; Kerslake, Thomas W.; Scheiman, David A.

1999-01-01

The International Space Station (ISS) is a complex spacecraft that will take several years to assemble in orbit. During many of the assembly and maintenance procedures, the space station's large solar arrays must he locked, which can significantly reduce power generation. To date, power generation analyses have not included power generation from the backside of the solar cells in a desire to produce a conservative analysis. This paper describes the testing of ISS solar cell backside power generation, analytical modeling and analysis results on an ISS assembly mission.

Thermal Deformation of Very Slender Triangular Rollable and Collapsible Booms

NASA Technical Reports Server (NTRS)

Stohlman, Olive R.; Loper, Erik R.

2016-01-01

Metallic triangular rollable and collapsible (TRAC) booms have deployed two Cubesat-based solar sails in low Earth orbit, making TRAC booms the most popular solar sail deployment method in practice. This paper presents some concerns and solutions surrounding the behavior of these booms in the space thermal environment. A 3.5-cm-tall, 4-meter-long TRAC boom of Elgiloy cobalt alloy, when exposed to direct sunlight in a 1 AU deep space environment, has a predicted tip motion of as much as 0.5 meters. Such large thermal deflections could generate unacceptable distortions in the shape of a supported solar sail, making attitude control of the solar sail spacecraft difficult or impossible. As a possible means of mitigating this issue, the thermal distortion behaviors of three alternative material TRAC booms are investigated and compared with the uncoated Elgiloy baseline boom. A tenfold decrease in induced curvature is shown to be possible relative to the baseline boom. Potential thermal distortions of the LightSail-A solar sail TRAC booms are also examined and compared, although inconclusively, with available on-orbit camera imagery.

Analysis of Nd3+:glass, solar-pumped, high-powr laser systems

NASA Technical Reports Server (NTRS)

Zapata, L. E.; Williams, M. D.

1989-01-01

The operating characteristics of Nd(3+):glass lasers energized by a solar concentrator were analyzed for the hosts YAG, silicate glass, and phosphate glass. The modeling is based on the slab zigzag laser geometry and assumes that chemical hardening methods for glass are successful in increasing glass hardness by a factor of 4. On this basis, it was found that a realistic 1-MW solar-pumped laser might be constructed from phosphate glass 4 sq m in area and 2 mm thick. If YAG were the host medium, a 1-MW solar-pumped laser need only be 0.5 sq m in area and 0.5 cm thick, which is already possible. In addition, Nd(3+) doped glass fibers were found to be excellent solar-pumped laser candidates. The small diameter of fibers eliminates thermal stress problems, and if their diameter is kept small (10 microns), they propagate a Gaussian single mode which can be expanded and transmitted long distances in space. Fiber lasers could then be used for communications in space or could be bundled and the individual beams summed or phase-matched for high-power operation.

Multi-physics simulations of space weather

NASA Astrophysics Data System (ADS)

Gombosi, Tamas; Toth, Gabor; Sokolov, Igor; de Zeeuw, Darren; van der Holst, Bart; Cohen, Ofer; Glocer, Alex; Manchester, Ward, IV; Ridley, Aaron

Presently magnetohydrodynamic (MHD) models represent the "workhorse" technology for simulating the space environment from the solar corona to the ionosphere. While these models are very successful in describing many important phenomena, they are based on a low-order moment approximation of the phase-space distribution function. In the last decade our group at the Center for Space Environment Modeling (CSEM) has developed the Space Weather Modeling Framework (SWMF) that efficiently couples together different models describing the interacting regions of the space environment. Many of these domain models (such as the global solar corona, the inner heliosphere or the global magnetosphere) are based on MHD and are represented by our multiphysics code, BATS-R-US. BATS-R-US can solve the equations of "standard" ideal MHD, but it can also go beyond this first approximation. It can solve resistive MHD, Hall MHD, semi-relativistic MHD (that keeps the displacement current), multispecies (different ion species have different continuity equations) and multifluid (all ion species have separate continuity, momentum and energy equations) MHD. Recently we added two-fluid Hall MHD (solving the electron and ion energy equations separately) and are working on extended magnetohydrodynamics with anisotropic pressures. This talk will show the effects of added physics and compare space weather simulation results to "standard" ideal MHD.

From space weather toward space climate time scales: Substorm analysis from 1993 to 2008

NASA Astrophysics Data System (ADS)

Tanskanen, E. I.; Pulkkinen, T. I.; Viljanen, A.; Mursula, K.; Partamies, N.; Slavin, J. A.

2011-05-01

Magnetic activity in the Northern Hemisphere auroral region was examined during solar cycles 22 and 23 (1993-2008). Substorms were identified from ground-based magnetic field measurements by an automated search engine. On average, 550 substorms were observed per year, which gives in total about 9000 substorms. The interannual, seasonal and solar cycle-to-cycle variations of the substorm number (Rss), substorm duration (Tss), and peak amplitude (Ass) were examined. The declining phases of both solar cycles 22 and 23 were more active than the other solar cycle phases due to the enhanced solar wind speed. The spring substorms during the declining solar cycle phase (∣Ass,decl∣ = 500 nT) were 25% larger than the spring substorms during the ascending solar cycle years (∣Ass,acs∣ = 400 nT). The following seasonal variation was found: the most intense substorms occurred during spring and fall, the largest substorm frequency in the Northern Hemisphere winter, and the longest-duration substorms in summer. Furthermore, we found a winter-summer asymmetry in the substorm number and duration, which is speculated to be due to the variations in the ionospheric conductivity. The solar cycle-to-cycle variation was found in the yearly substorm number and peak amplitude. The decline from the peak substorm activity in 1994 and 2003 to the following minima took 3 years during solar cycle 22, while it took 6 years during solar cycle 23.

Plasma physics and the 2013-2022 decadal survey in solar and space physics

NASA Astrophysics Data System (ADS)

Baker, Daniel N.

2016-11-01

The U.S. National Academies established in 2011 a steering committee to develop a comprehensive strategy for solar and space physics research. This updated and extended the first (2003) solar and space physics decadal survey. The latest decadal study implemented a 2008 Congressional directive to NASA for the fields of solar and space physics, but also addressed research in other federal agencies. The new survey broadly canvassed the fields of research to determine the current state of the discipline, identified the most important open scientific questions, and proposed the measurements and means to obtain them so as to advance the state of knowledge during the years 2013-2022. Research in this field has sought to understand: dynamical behaviour of the Sun and its heliosphere; properties of the space environments of the Earth and other solar system bodies; multiscale interaction between solar system plasmas and the interstellar medium; and energy transport throughout the solar system and its impact on the Earth and other solar system bodies. Research in solar and space plasma processes using observation, theory, laboratory studies, and numerical models has offered the prospect of understanding this interconnected system well enough to develop a predictive capability for operational support of civil and military space systems. We here describe the recommendations and strategic plans laid out in the 2013-2022 decadal survey as they relate to measurement capabilities and plasma physical research. We assess progress to date. We also identify further steps to achieve the Survey goals with an emphasis on plasma physical aspects of the program.

Probabilistic Solar Wind Forecasting Using Large Ensembles of Near-Sun Conditions With a Simple One-Dimensional "Upwind" Scheme

NASA Astrophysics Data System (ADS)

Owens, Mathew J.; Riley, Pete

2017-11-01

Long lead-time space-weather forecasting requires accurate prediction of the near-Earth solar wind. The current state of the art uses a coronal model to extrapolate the observed photospheric magnetic field to the upper corona, where it is related to solar wind speed through empirical relations. These near-Sun solar wind and magnetic field conditions provide the inner boundary condition to three-dimensional numerical magnetohydrodynamic (MHD) models of the heliosphere out to 1 AU. This physics-based approach can capture dynamic processes within the solar wind, which affect the resulting conditions in near-Earth space. However, this deterministic approach lacks a quantification of forecast uncertainty. Here we describe a complementary method to exploit the near-Sun solar wind information produced by coronal models and provide a quantitative estimate of forecast uncertainty. By sampling the near-Sun solar wind speed at a range of latitudes about the sub-Earth point, we produce a large ensemble (N = 576) of time series at the base of the Sun-Earth line. Propagating these conditions to Earth by a three-dimensional MHD model would be computationally prohibitive; thus, a computationally efficient one-dimensional "upwind" scheme is used. The variance in the resulting near-Earth solar wind speed ensemble is shown to provide an accurate measure of the forecast uncertainty. Applying this technique over 1996-2016, the upwind ensemble is found to provide a more "actionable" forecast than a single deterministic forecast; potential economic value is increased for all operational scenarios, but particularly when false alarms are important (i.e., where the cost of taking mitigating action is relatively large).

Probabilistic Solar Wind Forecasting Using Large Ensembles of Near-Sun Conditions With a Simple One-Dimensional "Upwind" Scheme.

PubMed

Owens, Mathew J; Riley, Pete

2017-11-01

Long lead-time space-weather forecasting requires accurate prediction of the near-Earth solar wind. The current state of the art uses a coronal model to extrapolate the observed photospheric magnetic field to the upper corona, where it is related to solar wind speed through empirical relations. These near-Sun solar wind and magnetic field conditions provide the inner boundary condition to three-dimensional numerical magnetohydrodynamic (MHD) models of the heliosphere out to 1 AU. This physics-based approach can capture dynamic processes within the solar wind, which affect the resulting conditions in near-Earth space. However, this deterministic approach lacks a quantification of forecast uncertainty. Here we describe a complementary method to exploit the near-Sun solar wind information produced by coronal models and provide a quantitative estimate of forecast uncertainty. By sampling the near-Sun solar wind speed at a range of latitudes about the sub-Earth point, we produce a large ensemble (N = 576) of time series at the base of the Sun-Earth line. Propagating these conditions to Earth by a three-dimensional MHD model would be computationally prohibitive; thus, a computationally efficient one-dimensional "upwind" scheme is used. The variance in the resulting near-Earth solar wind speed ensemble is shown to provide an accurate measure of the forecast uncertainty. Applying this technique over 1996-2016, the upwind ensemble is found to provide a more "actionable" forecast than a single deterministic forecast; potential economic value is increased for all operational scenarios, but particularly when false alarms are important (i.e., where the cost of taking mitigating action is relatively large).

Solar and Space Physics PhD Production and Job Availability: Implications for the Future of the Space Weather Research Workforce

NASA Astrophysics Data System (ADS)

Moldwin, M.; Morrow, C. A.; Moldwin, L. A.; Torrence, J.

2012-12-01

To assess the state-of-health of the field of Solar and Space Physics an analysis of the number of Ph.D.s produced and number of Job Postings each year was done for the decade 2001-2010. To determine the number of Ph.D's produced in the field, the University of Michigan Ph.D. Dissertation Archive (Proquest) was queried for Solar and Space Physics dissertations produced in North America. The field generated about 30 Ph.D. per year from 2001 to 2006, but then saw the number increase to 50 to 70 per year for the rest of the decade. Only 14 institutions account for the majority of Solar and Space Physics PhDs. To estimate the number of jobs available each year in the field, a compilation of the job advertisements listed in the American Astronomical Society's Solar Physics Division (SPD) and the American Geophysical Union's Space Physics and Aeronomy (SPA) electronic newsletters was done. The positions were sorted into four types (Faculty, Post-doctoral Researcher, and Scientist/Researcher or Staff), institution type (academic, government lab, or industry) and if the position was located inside or outside the United States. Overall worldwide, 943 Solar and Space Physics positions were advertised over the decade. Of this total, 52% were for positions outside the US. Within Solar Physics, 44% of the positions were in the US, while in Space Physics 57% of the positions were for US institutions. The annual average for positions in the US were 26.9 for Solar Physics and 31.5 for Space Physics though there is much variability year-to-year particularly in Solar Physics positions outside the US. A disconcerting trend is a decline in job advertisements in the last two years for Solar Physics positions and between 2009 and 2010 for Space Physics positions. For both communities within the US in 2010, the total job ads reached their lowest levels in the decade (14), approximately half the decadal average number of job advertisements.

Global Navigation Satellite Systems and Space Weather: Building upon the International Space Weather Initiative

NASA Astrophysics Data System (ADS)

Gadimova, S. H.; Haubold, H. J.

2014-01-01

Globally there is growing interest in better unders tanding solar-terrestrial interactions, particularly patterns and trends in space weather. This is not only for scientific reasons, but also because the reliable operation of ground-based and space-based assets and infrastructures is increasingly dependent on their robustness against the detrimental effects of space weather. Consequently, in 2009, the United Nations Committee on the Peaceful Uses of Outer Space (COPUOS) proposed the International Space Weather Initiative (ISWI), as a follow-up activity to the International Heliophysical Year 2007 (IHY2007), to be implemented under a three-year workplan from 2010 to 2012 (UNGA Document, A/64/20). All achievements of international cooperation and coordination for ISWI, including instrumentation, data analysis, modelling, education, training and public outreach, are made a vailable through the ISWI Newsletter and the ISWI Website (http://www.iswi-secretariat.org/). Since the last solar maximum in 2000, societal dependence on global navigation satellite system (GNSS) has increased substantially. This situation has brought increasing attention to the subject of space weather and its effects on GNSS systems and users. Results concerning the impact of space weather on GNSS are made available at the Information Portal (www.unoosa.org) of the International Committee on Global Navigati on Satellite Systems (ICG). This paper briefly reviews the curre nt status of ISWI with regard to GNSS.

Photons and Ground-Based

NASA Technical Reports Server (NTRS)

Spann, James F.; Moore, Thomas E.

2017-01-01

A Conference on Measurement Techniques for Solar and Space Physics was held on 20-24 April 2015 in Boulder, Colorado, at the National Center for Atmospheric Research Center Green Campus. The present volume collects together the conference papers for photons and ground-based categories. This gathering of over 200 scientists and instrumentalists was born out of the desire to collect in one place the latest experiment and instrument technologies required for advancement of scientific knowledge in the disciplines of solar and space physics. The two goals for this conference and the subsequent publication of its content are (a) to describe measurement techniques and technology development needed to advance high priority science in the fields of solar and space physics; and (b) to provide a survey or reference of techniques for in situ measurement and remote sensing of space plasmas. Towards this end, our goal has always been inspired by the two 1998 Geophysical Monographs (Nos. 102 and 103) entitled, "Measurement Techniques in Space Plasmas" (particles and fields) [Pfaff et al., 1998a, 1998b], which have served as a reference and resource for advanced students, engineers, and scientists who wish to learn the fundamentals of measurement techniques and technology in this field. Those monographs were the product of an American Geophysical Union Chapman Conference that took place in Santa Fe, NM, in 1995: "Measurement Techniques in Space Plasmas-What Works, What Doesn't." Two decades later, we believe that it is appropriate to revisit this subject, in light of recent advances in technology, research platforms, and analysis techniques. Moreover, we now include direct measurements of neutral gases in the upper atmosphere, optical imaging techniques, and remote observations in space and on the ground. Accordingly, the workshop was organized among four areas of measurement techniques: particles, fields, photons, and ground-based. This two-set volume is largely composed of the content of that workshop. Special attention is given to those techniques and technologies that demonstrate promise of significant advancement in measurements that will enable the highest priority science as described in the 2012 National Research Council Decadal Survey [Baker and Zurbuchen et al., 2013]. Additionally, a broad tutorial survey of the current technologies is provided to serve as reference material and as a basis from which advanced and innovative ideas can be discussed and pursued. Included are instrumentation and techniques to observe the solar environment from its interior to its outer atmosphere, the heliosphere out to the interstellar regions, in geospace, and other planetary magnetospheres and atmospheres. To make significant progress in priority science as expressed in the National Research Council solar and space physics decadal survey and recent NASA Heliophysics roadmaps, identification of enabling new measurement techniques and technologies to be developed is required. Also, it is valuable to the community and future scientists and engineers to have a complete survey of the techniques and technologies used by the practitioners of solar and space physics. As with the 1995 conference and subsequent 1998 publication, it is incumbent on the community to identify those measurements that are particularly challenging and still require new techniques to be identified and tested to enable the necessary accuracy and resolution of certain parameters to be achieved. The following is a partial list of the measurement technique categories that are featured in these special publications: Particles; Thermal plasma to MeV energetic particles, neutral gas properties including winds, density, temperature, and composition, and enhanced neutral atom imaging; Fields; DC electric and magnetic fields, plasma waves, and electron drift instruments from which the plasma velocity information provides a measure of the DC electric field; Photons; Instruments sensitive from the near-infrared to X-rays; Contributions of techniques and technology for optical design, optical components, sensors, material selection for cameras, telescopes, and spectrographs; Ground based; Remote sensing methods for solar and geospace activity and space weather. The focus includes solar observatories, all-sky cameras, lidars, and ionosphere thermosphere mesosphere observatory systems such as radars, ionosondes, GPS receivers, magnetometers, conjugate observations, and airborne campaigns. The present volume collects together the papers for photons and ground-based categories. The companion volume collects together the papers for particles and fields categories. It is recognized that there are measurement techniques that overlap among the four categories. For example, use of microchannel plate detectors is used in photon and particle measurement techniques or the observation of visible photons and magnetic fields in space and on the ground share common technologies. Therefore, the reader should consider the entire collection of papers as they seek to understand particular applications. We hope that these volumes will be as valuable as a reference for our community as the earlier 1998 volumes have been.

Introduction: Photons and Ground-Based

NASA Technical Reports Server (NTRS)

Spann, James; Moore, Thomas

2017-01-01

A Conference on Measurement Techniques for Solar and Space Physics was held on 20-24 April 2015 in Boulder, Colorado, at the National Center for Atmospheric Research Center Green Campus. The present volume collects together the conference papers for photons and ground-based categories. This gathering of over 200 scientists and instrumentalists was born out of the desire to collect in one place the latest experiment and instrument technologies required for advancement of scientific knowledge in the disciplines of solar and space physics. The two goals for this conference and the subsequent publication of its content are (a) to describe measurement techniques and technology development needed to advance high priority science in the fields of solar and space physics; and (b) to provide a survey or reference of techniques for in situ measurement and remote sensing of space plasmas. Towards this end, our goal has always been inspired by the two 1998 Geophysical Monographs (Nos. 102 and 103) entitled, "Measurement Techniques in Space Plasmas" (particles and fields) [Pfaff et al., 1998a, 1998b], which have served as a reference and resource for advanced students, engineers, and scientists who wish to learn the fundamentals of measurement techniques and technology in this field. Those monographs were the product of an American Geophysical Union Chapman Conference that took place in Santa Fe, NM, in 1995: "Measurement Techniques in Space Plasmas-What Works, What Doesn't." Two decades later, we believe that it is appropriate to revisit this subject, in light of recent advances in technology, research platforms, and analysis techniques. Moreover, we now include direct measurements of neutral gases in the upper atmosphere, optical imaging techniques, and remote observations in space and on the ground. Accordingly, the workshop was organized among four areas of measurement techniques: particles, fields, photons, and ground-based. This two-set volume is largely composed of the content of that workshop. Special attention is given to those techniques and technologies that demonstrate promise of significant advancement in measurements that will enable the highest priority science as described in the 2012 National Research Council Decadal Survey [Baker and Zurbuchen et al., 2013]. Additionally, a broad tutorial survey of the current technologies is provided to serve as reference material and as a basis from which advanced and innovative ideas can be discussed and pursued. Included are instrumentation and techniques to observe the solar environment from its interior to its outer atmosphere, the heliosphere out to the interstellar regions, in geospace, and other planetary magnetospheres and atmospheres. To make significant progress in priority science as expressed in the National Research Council solar and space physics decadal survey and recent NASA Heliophysics roadmaps, identification of enabling new measurement techniques and technologies to be developed is required. Also, it is valuable to the community and future scientists and engineers to have a complete survey of the techniques and technologies used by the practitioners of solar and space physics. As with the 1995 conference and subsequent 1998 publication, it is incumbent on the community to identify those measurements that are particularly challenging and still require new techniques to be identified and tested to enable the necessary accuracy and resolution of certain parameters to be achieved. The following is a partial list of the measurement technique categories that are featured in these special publications: Particles; Thermal plasma to MeV energetic particles, neutral gas properties including winds, density, temperature, and composition, and enhanced neutral atom imaging; Fields; DC electric and magnetic fields, plasma waves, and electron drift instruments from which the plasma velocity information provides a measure of the DC electric field; Photons; Instruments sensitive from the near-infrared to X-rays; Contributions of techniques and technology for optical design, optical components, sensors, material selection for cameras, telescopes, and spectrographs; Ground based; Remote sensing methods for solar and geospace activity and space weather. The focus includes solar observatories, all-sky cameras, lidars, and ionosphere thermosphere mesosphere observatory systems such as radars, ionosondes, GPS receivers, magnetometers, conjugate observations, and airborne campaigns. The present volume collects together the papers for photons and ground-based categories. The companion volume collects together the papers for particles and fields categories. It is recognized that there are measurement techniques that overlap among the four categories. For example, use of microchannel plate detectors is used in photon and particle measurement techniques or the observation of visible photons and magnetic fields in space and on the ground share common technologies. Therefore, the reader should consider the entire collection of papers as they seek to understand particular applications. We hope that these volumes will be as valuable as a reference for our community as the earlier 1998 volumes have been.

P6 Truss, Photovoltaic (PV) Solar Array Wing (SAW)

NASA Image and Video Library

2000-12-07

STS097-376-019 (7 December 2000) --- A close-up view of the P6 solar array on the International Space Station (ISS), backdropped against the blackness of space and the Earth’s horizon. The P6 solar array is the first of eight sets of solar arrays that at the completion of the space station construction in 2006, will comprise the station’s electrical power system, converting sunlight to electricity.

P6 Truss, Photovoltaic (PV) Solar Array Wing (SAW)

NASA Image and Video Library

2000-12-07

STS097-376-006 (7 Dec 2000) --- A close-up view of the P6 solar array on the International Space Station (ISS), backdropped against the blackness of space and the Earth?s horizon. The P6 solar array is the first of eight sets of solar arrays that at the completion of the space station construction in 2006, will comprise the station?s electrical power system, converting sunlight to electricity.

Solar Power Generation in Extreme Space Environments

NASA Technical Reports Server (NTRS)

Elliott, Frederick W.; Piszczor, Michael F.

2016-01-01

The exploration of space requires power for guidance, navigation, and control; instrumentation; thermal control; communications and data handling; and many subsystems and activities. Generating sufficient and reliable power in deep space through the use of solar arrays becomes even more challenging as solar intensity decreases and high radiation levels begin to degrade the performance of photovoltaic devices. The Extreme Environments Solar Power (EESP) project goal is to develop advanced photovoltaic technology to address these challenges.

The OAST space power program

NASA Technical Reports Server (NTRS)

Bennett, Gary L.

1991-01-01

The NASA Office of Aeronautics and Space Technology (OAST) space power program was established to provide the technology base to meet power system requirements for future space missions, including the Space Station, earth orbiting spacecraft, lunar and planetary bases, and solar system exploration. The program spans photovoltaic energy conversion, chemical energy conversion, thermal energy conversion, power management, thermal management, and focused initiatives on high-capacity power, surface power, and space nuclear power. The OAST space power program covers a broad range of important technologies that will enable or enhance future U.S. space missions. The program is well under way and is providing the kind of experimental and analytical information needed for spacecraft designers to make intelligent decisions about future power system options.

Electron Radiation Effects on Candidate Solar Sail Material

NASA Technical Reports Server (NTRS)

Edwards, David L.; Hollerman, William A.; Hubbs, Whitney S.; Gray, Perry A.; Wertz, George E.; Hoppe, David T.; Nehls, Mary K.; Semmel, Charles L.

2003-01-01

Solar sailing is a unique form of propulsion where a spacecraft gains momentum from incident photons. Solar sails are not limited by reaction mass and provide continual acceleration, reduced only by the lifetime of the lightweight film in the space environment and the distance to the Sun. Once thought to be difficult or impossible, solar sailing has come out of science fiction and into the realm of possibility. Any spacecraft using this propulsion method would need to deploy a thin sail that could be as large as many kilometers in extent. The availability of strong, ultra lightweight, and radiation resistant materials will determine the future of solar sailing. The National Aeronautics and Space Administration's (NASA) Marshall Space Flight Center (MSFC) is concentrating research into the utilization of ultra lightweight materials for spacecraft propulsion. The Space Environmental Effects Team at MSFC is actively characterizing candidate solar sail material to evaluate the thermo-optical and mechanical properties after exposure to space environmental effects. This paper will describe the irradiation of candidate solar sail materials to energetic electrons, in vacuum, to determine the hardness of several candidate sail materials.

Engineering Resilience Into The Marine Expeditionary Units Resupply System Through Military Foraging

DTIC Science & Technology

2017-09-01

19 Figure 7. Solar Portable Alternative Communications Energy System ( SPACES ) Source...sustained operations ashore SPACES solar portable alternative communications energy system STOM ship-to-objective maneuver STSM ship-to-shore movement... Communications Energy System Solar Portable Alternative Communications Energy System ( SPACES ) is a man-portable energy generation system for mounted

Solar Electric Propulsion System Integration Technology (SEPSIT). Volume 2: Encke rendezvous mission and space vehicle functional description

NASA Technical Reports Server (NTRS)

Gardner, J. A.

1972-01-01

A solar electric propulsion system integration technology study is discussed. Detailed analyses in support of the solar electric propulsion module were performed. The thrust subsystem functional description is presented. The space vehicle and the space mission to which the propulsion system is applied are analyzed.

Energy Action Day

NASA Image and Video Library

2017-10-25

John Sherwin of the Florida Solar Energy Center in Cocoa speaks during the Energy Action Day employee event held in NASA Kennedy Space Center's Space Station Processing Facility. Part of Energy Awareness Month, the event featured subject matter experts in the area of solar energy, its connections to the space program and options for residential solar power.

History of Hubble Space Telescope (HST)

NASA Image and Video Library

1985-01-01

This is a view of a solar cell blanket deployed on a water table during the Solar Array deployment test. The Hubble Space Telescope (HST) Solar Arrays provide power to the spacecraft. The arrays are mounted on opposite sides of the HST, on the forward shell of the Support Systems Module. Each array stands on a 4-foot mast that supports a retractable wing of solar panels 40-feet (12.1-meters) long and 8.2-feet (2.5-meters) wide, in full extension. The arrays rotate so that the solar cells face the Sun as much as possible to harness the Sun's energy. The Space Telescope Operations Control Center at the Goddard Space Center operates the array, extending the panels and maneuvering the spacecraft to focus maximum sunlight on the arrays. The purpose of the HST, the most complex and sensitive optical telescope ever made, is to study the cosmos from a low-Earth orbit. By placing the telescope in space, astronomers are able to collect data that is free of the Earth's atmosphere. The HST Solar Array was designed by the European Space Agency and built by British Aerospace. The Marshall Space Flight Center had overall responsibility for design, development, and construction of the HST.

NASA's Chemical Transfer Propulsion Program for Pathfinder

NASA Technical Reports Server (NTRS)

Hannum, Ned P.; Berkopec, Frank D.; Zurawski, Robert L.

1989-01-01

Pathfinder is a research and technology project, with specific deliverables, initiated by the National Aeronautics and Space Administration (NASA) which will strengthen the technology base of the United States civil space program in preparation for future space exploration missions. Pathfinder begins in Fiscal Year 1989, and is to advance a collection of critical technologies for these missions and ensure technology readiness for future national decisions regarding exploration of the solar system. The four major thrusts of Pathfinder are: surface exploration, in-space operations, humans-in-space, and space transfer. The space transfer thrust will provide the critical technologies needed for transportation to, and return from, the Moon, Mars, and other planets in the solar system, as well as for reliable and cost-effective Earth-orbit operations. A key element of this thrust is the Chemical Transfer Propulsion program which will provide the propulsion technology for high performance, liquid oxygen/liquid hydrogen expander cycle engines which may be operated and maintained in space. Described here are the program overview including the goals and objectives, management, technical plan, and technology transfer for the Chemical Transfer Propulsion element of Pathfinder.

In-Space Propulsion: Connectivity to In-Space Fabrication and Repair

NASA Technical Reports Server (NTRS)

Johnson, L.; Harris, D.; Trausch, A.; Matloff, G. L.; Taylor, T.; Cutting, K.

2005-01-01

The connectivity between new in-space propulsion technologies and the ultimate development of an in-space fabrication and repair infrastructure are described in this Technical Memorandum. A number of advanced in-space propulsion technologies are being developed by NASA, many of which are directly relevant to the establishment of such an in-space infrastructure. These include aerocapture, advanced solar-electric propulsion, solar-thermal propulsion, advanced chemical propulsion, tethers, and solar photon sails. Other, further-term technologies have also been studied to assess their utility to the development of such an infrastructure.

Light intensity dependence of open-circuit voltage and short-circuit current of polymer/fullerene solar cells

NASA Astrophysics Data System (ADS)

Koster, L. Jan A.; Mihailetchi, Valentin D.; Ramaker, Robert; Xie, Hangxing; Blom, Paul W. M.

2006-04-01

The open-circuit voltage (Voc) of polymer/fullerene bulk heterojunction solar cells is investigated as a function of light intensity for different temperatures. The observed photogenerated current and V oc are at variance with classical p-n junctionbased models. The influence of light intensity and recombination strength on V oc is consistently explained by a model based on the notion that the quasi-Fermi levels are constant throughout the device, including both drift and diffusion of charge carriers. The light intensity dependence of the short-circuit current density (J sc) is also addressed. A typical feature of polymer/fullerene based solar cells is that Jsc does not scale exactly linearly with light intensity (I). Instead, a power law relationship is found given by Jsc~ Iα, where α ranges from 0.9 to 1. In a number of reports this deviation from unity is attributed to the occurrence of bimolecular recombination. We demonstrate that the dependence of the photocurrent in bulk heterojunction solar cells is governed by the build-up of space charge in the device. The occurrence of space-charge stems from the difference in charge carrier mobility of electrons and holes. In blends of poly(3-hexylthiophene) and 6,6- phenyl C61-butyric acid methyl ester this mobility difference can be tuned in between one and three orders of magnitude, depending on the annealing conditions. This allows us to experimentally verify the relation between space charge build-up and intensity dependence of Jsc. Model calculations confirm that bimolecular recombination leads only to a typical loss of 1% of all free charge carriers at Jsc for these devices. Therefore, bimolecular recombination plays only a minor role as compared to the effect of space charge in the intensity dependence of J sc.

Study of a Solar Sensor for use in Space Vehicle Orientation Control Systems

NASA Technical Reports Server (NTRS)

Spencer, Paul R.

1961-01-01

The solar sensor described herein may be used for a variety of space operations requiring solar orientation. The use of silicon solar cells as the sensing elements provides the sensor with sufficient capability to withstand the hazards of a space environment. A method of arranging the cells in a sensor consists simply of mounting them at a large angle to the base. The use of an opaque shield placed between the cells and perpendicular to the base enhances the small-angle sensitivity while adding slightly to the bulk of the sensor. The difference in illumination of these cells as the result of an oblique incidence of the light rays from the reference source causes an electrical error signal which, when used in a battery-bridge circuit, requires a minimum of electrical processing for use in a space-vehicle orientation control system. An error which could occur after prolonged operation of the sensor is that resulting from asymmetrical aging of opposite cells. This could be periodically corrected with a balance potentiometer. A more routine error in the sensor is that produced by reflected earth radiation. This error may be eliminated over a large portion of the operation time by restricting the field of view and, consequently, the capture capability. A more sophisticated method of eliminating this error is to use separate sensors, for capture and fine pointing, along with a switching device. An experimental model has been constructed and tested to yield an output sensitivity of 1.2 millivolts per second of arc with a load resistance of 1,000 ohms and a reference light source of approximately 1,200 foot-candles delivered at the sensor.

NASA philosophy concerning space stations as operations centers for construction and maintenance of large orbiting energy systems

NASA Technical Reports Server (NTRS)

Freitag, R. F.

1976-01-01

Future United States plans for manned space-flight activities are summarized, emphasizing the long-term goals of achieving permanent occupancy and limited self-sufficiency in space. NASA-sponsored studies of earth-orbiting Space Station concepts are reviewed along with lessons learned from the Skylab missions. Descriptions are presented of the Space Transportation System, the Space Construction Base, and the concept of space industrialization (the processing and manufacturing of goods in space). Future plans for communications satellites, solar-power satellites, terrestrial observations from space stations, and manned orbital-transfer vehicles are discussed.

Utility of Thin-Film Solar Cells on Flexible Substrates for Space Power

NASA Technical Reports Server (NTRS)

Dickman, J. E.; Hepp, A. F.; Morel, D. L.; Ferekides, C. S.; Tuttle, J. R.; Hoffman, D. J.; Dhere, N. G.

2004-01-01

The thin-film solar cell program at NASA GRC is developing solar cell technologies for space applications which address two critical metrics: specific power (power per unit mass) and launch stowed volume. To be competitive for many space applications, an array using thin film solar cells must significantly increase specific power while reducing stowed volume when compared to the present baseline technology utilizing crystalline solar cells. The NASA GRC program is developing two approaches. Since the vast majority of the mass of a thin film solar cell is in the substrate, a thin film solar cell on a very lightweight flexible substrate (polymer or metal films) is being developed as the first approach. The second approach is the development of multijunction thin film solar cells. Total cell efficiency can be increased by stacking multiple cells having bandgaps tuned to convert the spectrum passing through the upper cells to the lower cells. Once developed, the two approaches will be merged to yield a multijunction, thin film solar cell on a very lightweight, flexible substrate. The ultimate utility of such solar cells in space require the development of monolithic interconnections, lightweight array structures, and ultra-lightweight support and deployment techniques.

Space solar cell research - Problems and potential

NASA Technical Reports Server (NTRS)

Flood, Dennis J.

1986-01-01

The value of a passive, maintenance-free, renewable energy source was immediately recognized in the early days of the space program, and the silicon solar cell, despite its infancy, was quickly pressed into service. Efficiencies of those early space solar arrays were low, and lifetimes shorter than hoped for, but within a decade significant advances had been made in both areas. Better performance was achieved because of a variety of factors, ranging from improvements in silicon single crystal material, to better device designs, to a better understanding of the factors that affect the performance of a solar cell in space. Chief among the latter, particularly for the mid-to-high altitude (HEO) and geosynchronous (GEO) orbits, are the effects of the naturally occurring particulate radiation environment. Although not as broadly important to the photovoltaic community at large as increased efficiency, the topic of radiation damage is critically important to use of solar cells in space, and is a major component of the NASA research program in space photovoltaics. This paper will give a brief overview of some of the opportunities and challenges for space photovoltaic applications, and will discuss some of the current reseach directed at achieving high efficiency and controlling the effects of radiation damage in space solar cells.

Solar heating, cooling, and domestic hot water system installed at Kaw Valley State Bank and Trust Company, Topeka, Kansas

NASA Technical Reports Server (NTRS)

1980-01-01

The building has approximately 5600 square feet of conditioned space. Solar energy was used for space heating, space cooling, and preheating domestic hot water (DHW). The solar energy system had an array of evacuated tube-type collectors with an area of 1068 square feet. A 50/50 solution of ethylene glycol and water was the transfer medium that delivered solar energy to a tube-in-shell heat exchanger that in turn delivered solar heated water to a 1100 gallon pressurized hot water storage tank. When solar energy was insufficient to satisfy the space heating and/or cooling demand, a natural gas-fired boiler provided auxiliary energy to the fan coil loops and/or the absorption chillers. Extracts from the site files, specification references, drawings, and installation, operation and maintenance instructions are presented.

Thermal performance evaluation of the Northrop model NSC-01-0732 concentrating solar collector array at outdoor conditions. [Marshall Space Flight Center solar house test facility

NASA Technical Reports Server (NTRS)

1979-01-01

The thermal efficiency of the concentrating, tracking solar collector was tested after ten months of operation at the Marshall Space Flight Center solar house. The test procedures and results are presented.

Research Technology

NASA Image and Video Library

2004-04-15

Harnessing the Sun's energy through Solar Thermal Propulsion will propel vehicles through space by significantly reducing weight, complexity, and cost while boosting performance over current conventional upper stages. Another solar powered system, solar electric propulsion, demonstrates ion propulsion is suitable for long duration missions. Pictured is an artist's concept of space flight using solar thermal propulsion.

The Ultimate Destination: Choice of Interplanetary Exploration Path can define Future of Interstellar Spaceflight

NASA Astrophysics Data System (ADS)

Silin, D. V.

Manned interstellar spaceflight is facing multiple challenges of great magnitude; among them are extremely large distances and the lack of known habitable planets other than Earth. Many of these challenges are applicable to manned space exploration within the Solar System to the same or lesser degree. If these issues are resolved on an interplanetary scale, better position to pursue interstellar exploration can be reached. However, very little progress (if any) was achieved in manned space exploration since the end of Space Race. There is no lack of proposed missions, but all of them require considerable technological and financial efforts to implement while yielding no tangible benefits that would justify their costs. To overcome this obstacle highest priority in future space exploration plans should be assigned to the creation of added value in outer space. This goal can be reached if reductions in space transportation, construction and maintenance of space-based structures costs are achieved. In order to achieve these requirements several key technologies have to be mastered, such as near-Earth object mining, space- based manufacturing, agriculture and structure assembly. To keep cost and difficulty under control next exploration steps can be limited to nearby destinations such as geostationary orbit, low lunar orbit, Moon surface and Sun-Earth L1 vicinity. Completion of such a program will create a solid foundation for further exploration and colonization of the Solar System, solve common challenges of interplanetary and interstellar spaceflight and create useful results for the majority of human population. Another important result is that perception of suitable destinations for interstellar missions will change significantly. If it becomes possible to create habitable and self-sufficient artificial environments in the nearby interplanetary space, Earth-like habitable planets will be no longer required to expand beyond our Solar System. Large fraction of the stars in the observable Universe will become valid targets for interstellar missions.

Near Sun Free-Space Optical Communications from Space

NASA Technical Reports Server (NTRS)

Biswas, Abhijit; Khatri, F.; Boroson, D.

2006-01-01

Free-space optical communications offers expanded data return capacity, from probes distributed throughout the solar system and beyond. Space-borne and Earth-based optical transceivers used for communicating optically, will periodically encounter near Sun pointing. This will result in an increase in the scattered background light flux, often contributing to degraded link performance. The varying duration of near Sun pointing link operations relative to the location of space-probes, is discussed in this paper. The impact of near Sun pointing on link performance for a direct detection photon-counting communications system is analyzed for both ground- and space-based Earth receivers. Finally, impact of near Sun pointing on spaceborne optical transceivers is discussed.

Analysis of radiative and phase-change phenomena with application to space-based thermal energy storage

NASA Technical Reports Server (NTRS)

Lund, Kurt O.

1991-01-01

The simplified geometry for the analysis is an infinite, axis symmetric annulus with a specified solar flux at the outer radius. The inner radius is either adiabatic (modeling Flight Experiment conditions), or convective (modeling Solar Dynamic conditions). Liquid LiF either contacts the outer wall (modeling ground based testing), or faces a void gap at the outer wall (modeling possible space based conditions). The analysis is presented in three parts: Part 3 considers and adiabatic inner wall and linearized radiation equations; part 2 adds effects of convection at the inner wall; and part 1 includes the effect of the void gap, as well as previous effects, and develops the radiation model further. The main results are the differences in melting behavior which can occur between ground based 1 g experiments and the microgravity flight experiments. Under 1 gravity, melted PCM will always contact the outer wall having the heat flux source, thus providing conductance from this source to the phase change front. In space based tests where a void gap may likely form during solidification, the situation is reversed; radiation is now the only mode of heat transfer and the majority of melting takes place from the inner wall.

Deployable Propulsion and Power Systems for Solar System Exploration

NASA Technical Reports Server (NTRS)

Johnson, Les; Carr, John

2017-01-01

NASA is developing thin-film based, deployable propulsion, power and communication systems for small spacecraft that could provide a revolutionary new capability allowing small spacecraft exploration of the solar system. The Near Earth Asteroid (NEA) Scout reconnaissance mission will demonstrate solar sail propulsion on a 6U CubeSat interplanetary spacecraft and lay the groundwork for their future use in deep space science and exploration missions. Solar sails use sunlight to propel vehicles through space by reflecting solar photons from a large, mirror-like sail made of a lightweight, highly reflective material. This continuous photon pressure provides propellantless thrust, allowing for very high delta V maneuvers on long-duration, deep space exploration. Since reflected light produces thrust, solar sails require no onboard propellant. The Lightweight Integrated Solar Array and Transceiver (LISA-T) is a launch stowed, orbit deployed array on which thin-film photovoltaic and antenna elements are embedded. Inherently, small satellites are limited in surface area, volume, and mass allocation; driving competition between power, communications, and GN&C (guidance navigation and control) subsystems. This restricts payload capability and limits the value of these low-cost satellites. LISA-T is addressing this issue, deploying large-area arrays from a reduced volume and mass envelope - greatly enhancing power generation and communications capabilities of small spacecraft. The NEA Scout mission, funded by NASA's Advanced Exploration Systems Program and managed by NASA MSFC, will use the solar sail as its primary propulsion system, allowing it to survey and image one or more NEA's of interest for possible future human exploration. NEA Scout uses a 6U cubesat (to be provided by NASA's Jet Propulsion Laboratory), an 86 sq m solar sail and will weigh less than 12 kilograms. NEA Scout will be launched on the first flight of the Space Launch System in 2018. Similar in concept to the NEA Scout solar sail, the LISA-T array is designed to fit into a very small volume and provide abundant power and omnidirectional communications in just about any deployment configuration. The technology is being proposed for flight validation as early as 2019 in a low earth orbit demonstration using a 3U cubesat, of which less than 1U will be devoted to the LISA-T power and propulsion system. By leveraging recent advancements in thin films, photovoltaics and miniaturized electronics, new mission-level capabilities will be enabled aboard lower-cost small spacecraft instead of their more expensive, traditional counterparts, enabling a new generation of frequent, inexpensive deep space missions.

Geomagnetic and Solar Indices Data at NGDC

NASA Astrophysics Data System (ADS)

Mabie, J. J.

2012-12-01

The National Geophysical Data Center, Solar and Terrestrial Physics Indices program is a central repository for global indices derived at numerous organizations around the world. These datasets are used by customers to drive models, evaluate the solar and geomagnetic environment, and to understand space climate. Our goal is to obtain and disseminate this data in a timely and accurate manner, and to provide the short term McNish-Lincoln sunspot number prediction. NGDC is in partnership with the NOAA Space Weather Prediction Center (SWPC), University Center for Atmospheric Sciences (UCAR), the Potsdam Helmholtz Center (GFZ), the Solar Indices Data Center (SIDC), the World Data Center for Geomagnetism Kyoto and many other organizations. The large number of available indices and the complexity in how they are derived makes understanding the data one of the biggest challenges for the users of indices. Our data services include expertise in our indices and related datasets to provide feedback and analysis for our global customer base.

Energy Action Day

NASA Image and Video Library

2017-10-25

NASA Kennedy Space Center's Sam Ball, third from left, speaks during the Energy Action Day employee event held in NASA Kennedy Space Center's Space Station Processing Facility. Part of Energy Awareness Month, the event featured subject matter experts in the area of solar energy, its connections to the space program and options for residential solar power. From left to right are Nick Murdock, energy and water program manager at Kennedy; Chuck Tatro of NASA's Launch Services Program; Ball; Anuj Chokshi of FPL; Bill McMullen of Southern Power; John Sherwin of the Florida Solar Energy Center in Cocoa; and Lorraine Koss of the Brevard County Solar Co-op.

Recent Advances in Atmospheric, Solar-Terrestrial Physics and Space Weather From a North-South network of scientists [2006-2016] PART B : Results and Capacity Building

NASA Astrophysics Data System (ADS)

Amory-Mazaudier, C.; Fleury, R.; Petitdidier, M.; Soula, S.; Masson, F.; Davila, J.; Doherty, P.; Elias, A.; Gadimova, S.; Makela, J.; Nava, B.; Radicella, S.; Richardson, J.; Touzani, A.; Girgea Team

2017-12-01

This paper reviews scientific advances achieved by a North-South network between 2006 and 2016. These scientific advances concern solar terrestrial physics, atmospheric physics and space weather. This part B is devoted to the results and capacity building. Our network began in 1991, in solar terrestrial physics, by our participation in the two projects: International Equatorial Electrojet Year IEEY [1992-1993] and International Heliophysical Year IHY [2007-2009]. These two projects were mainly focused on the equatorial ionosphere in Africa. In Atmospheric physics our research focused on gravity waves in the framework of the African Multidisciplinary Monsoon Analysis project n°1 [2005-2009 ], on hydrology in the Congo river basin and on lightning in Central Africa, the most lightning part of the world. In Vietnam the study of a broad climate data base highlighted global warming. In space weather, our results essentially concern the impact of solar events on global navigation satellite system GNSS and on the effects of solar events on the circulation of electric currents in the earth (GIC). This research began in the framework of the international space weather initiative project ISWI [2010-2012]. Finally, all these scientific projects have enabled young scientists from the South to publish original results and to obtain positions in their countries. These projects have also crossed disciplinary boundaries and defined a more diversified education which led to the training of specialists in a specific field with knowledge of related scientific fields.

Three-dimensional exploration of the solar wind using observations of interplanetary scintillation

PubMed Central

TOKUMARU, Munetoshi

2013-01-01

The solar wind, a supersonic plasma flow continuously emanating from the Sun, governs the space environment in a vast region extending to the boundary of the heliosphere (∼100 AU). Precise understanding of the solar wind is of importance not only because it will satisfy scientific interest in an enigmatic astrophysical phenomenon, but because it has broad impacts on relevant fields. Interplanetary scintillation (IPS) of compact radio sources at meter to centimeter wavelengths serves as a useful ground-based method for investigating the solar wind. IPS measurements of the solar wind at a frequency of 327 MHz have been carried out regularly since the 1980s using the multi-station system of the Solar-Terrestrial Environment Laboratory (STEL) of Nagoya University. This paper reviews new aspects of the solar wind revealed from our IPS observations. PMID:23391604

Optimization of an Advanced Multi-Junction Solar-Cell Design for Space Environments (AM0) Using Nearly Orthogonal Latin Hypercubes

DTIC Science & Technology

2017-06-01

AN ADVANCED MULTI-JUNCTION SOLAR -CELL DESIGN FOR SPACE ENVIRONMENTS (AM0) USING NEARLY ORTHOGONAL LATIN HYPERCUBES by Silvio Pueschel June...ADVANCED MULTI-JUNCTION SOLAR -CELL DESIGN FOR SPACE ENVIRONMENTS (AM0) USING NEARLY ORTHOGONAL LATIN HYPERCUBES 5. FUNDING NUMBERS 6. AUTHOR(S) Silvio...multi-junction solar cells with Silvaco Atlas simulation software. It introduces the nearly orthogonal Latin hypercube (NOLH) design of experiments (DoE

REU Solar and Space Physics Summer School

NASA Astrophysics Data System (ADS)

Snow, M. A.; Wood, E. L.

2011-12-01

The Research Experience for Undergrads (REU) program in Solar and Space Physics at the University of Colorado begins with a week of lectures and labs on Solar and Space Physics. The students in our program come from a variety of majors (physics, engineering, meteorology, etc.) and from a wide range of schools (small liberal arts colleges up through large research universities). The majority of the students have never been exposed to solar and space physics before arriving in Boulder to begin their research projects. We have developed a week-long crash course in the field using the expertise of scientists in Boulder and the labs designed by the Center for Integrated Space Weather Modeling (CISM).

Summary of solar cell data from the Long Duration Exposure Facility (LDEF)

NASA Technical Reports Server (NTRS)

Hill, David C.; Rose, M. Frank

1994-01-01

The Long Duration Exposure Facility (LDEF) was composed of many separate experiments, some of which contained solar cells. These solar cells were distributed at various positions on the LDEF and, therefore, were exposed to the space environment with an orientational dependence. This report will address the space environmental effects on solar cells and solar cell assemblies (SCA's), including electrical interconnects and associated insulation blankets where flown in conjunction with solar cells.

Phase fluctuations model for EM wave propagation through solar scintillation at superior solar conjunction

NASA Astrophysics Data System (ADS)

Xu, Guanjun; Song, Zhaohui

2017-04-01

Traveling solar wind disturbances have a significant influence on radio wave characteristics during the superior solar conjunction communication. This paper considers the impact of solar scintillation on phase fluctuations of electromagnetic (EM) wave propagation during the superior solar conjunction. Based on the Geometric Optics approximation, the close-form approximation model for phase fluctuations is developed. Both effects of anisotropic temporal variations function of plasma irregularities and their power spectrum are presented and analyzed numerically. It is found that phase fluctuations rapidly decrease with increasing Sun-Earth-Probe angle and decrease with increasing frequency at the rate of 1/f2. Moreover, the role of various features of the solar wind irregularities and their influence on the EM wave characteristic parameters is studied and discussed. Finally, we study the phase fluctuations of typical cases in order to better understand the impact of phase fluctuations in future deep space communication scenarios during solar conjunction periods.

Emerging US Space Launch, Trends and Space Solar Power

NASA Technical Reports Server (NTRS)

Zapata, Edgar

2015-01-01

Reviews the state of the art of emerging US space launch and spacecraft. Reviews the NASA budget ascontext, while providing example scenarios. Connects what has been learned in space systems commercial partnershipsto a potential path for consideration by the space solar power community.

Expanding Public Outreach: The Solar System Ambassadors Program

NASA Astrophysics Data System (ADS)

Ferrari, K.

2001-12-01

The Solar System Ambassadors Program is a public outreach program designed to work with motivated volunteers across the nation. These competitively selected volunteers organize and conduct public events that communicate exciting discoveries and plans in Solar System research, exploration and technology through non-traditional forums. In 2001, 206 Ambassadors from almost all 50 states bring the excitement of space to the public. Ambassadors are space enthusiasts, who come from all walks of life. Last year, Ambassadors conducted almost 600 events that reached more than one-half million people in communities across the United States. The Solar System Ambassadors Program is sponsored by the Jet Propulsion Laboratory (JPL) in Pasadena, California, an operating division of the California Institute of Technology (Caltech) and a lead research and development center for the National Aeronautics and Space Administration (NASA). Participating JPL organizations include Cassini, Galileo, STARDUST, Outer Planets mission, Genesis, Ulysses, Voyager, Mars missions, Discovery missions NEAR and Deep Impact, Deep Space Network, Solar System Exploration Forum and the Education and Public Outreach Office. Each Ambassador participates in on-line (web-based) training sessions that provide interaction with NASA scientists, engineers and project team members. As such, each Ambassador's experience with the space program becomes personalized. Training sessions provide Ambassadors with general background on each mission and educate them concerning specific mission milestones, such as launches, planetary flybys, first image returns, arrivals, and ongoing key discoveries. Additionally, projects provide limited supplies of materials, online resource links and information. Integrating volunteers across the country in a public-engagement program helps optimize project funding set aside for education and outreach purposes, establishing a nationwide network of regional contacts. At the same time, members of communities across the country become an extended part of each mission's team and an important interface between the space exploration community and the general public at large. >http://www.jpl.nasa.gov/ambassador/front.html

Expanding Public Outreach: The Solar System Ambassadors Program

NASA Astrophysics Data System (ADS)

Ferrari, K. A.

2000-12-01

The Solar System Ambassadors Program is a public outreach program designed to work with motivated volunteers across the nation. Those volunteers organize and conduct public events that communicate exciting discoveries and plans in Solar System research, exploration and technology through non-traditional forums, e.g. community service clubs, libraries, museums, planetariums, ``star parties," mall displays, etc. In 2001, 200 Ambassadors from almost all 50 states bring the excitement of space to the public. Ambassadors are space enthusiasts, K-12 in-service educators, retirees, community college teachers, and other members of the general public interested in providing greater service and inspiration to the community at large. Last year, Ambassadors conducted approximately 600 events that directly reached more than one-half million people in communities across the United States. The Solar System Ambassadors Program is sponsored by the Jet Propulsion Laboratory (JPL) in Pasadena, California, an operating division of the California Institute of Technology (Caltech) and a lead research and development center for the National Aeronautics and Space Administration (NASA). Participating JPL projects include Cassini, Galileo, STARDUST, Outer Planets mission, Solar Probe, Genesis, Ulysses, Voyager, Mars missions, Discovery missions NEAR-Shoemaker and Deep Impact, and the Deep Space Network. Each Ambassador participates in on-line (web-based) training sessions that provide interaction with NASA scientists, engineers and project team members. As such, each Ambassador's experience with the space program becomes personalized. Training sessions provide Ambassadors with general background on each mission and educate concerning specific mission milestones, such as launches, planetary flybys, first image returns, arrivals, and ongoing key discoveries. Additionally, projects provide videos, slide sets, booklets, pamphlets, posters, postcards, lithographs, on-line materials, resource links and information. Integrating nation-wide volunteers in a public-engagement program helps optimize project funding set aside for education and outreach purposes. At the same time, members of communities across the country become an extended part of each mission's team and an important interface between the space exploration community and the general public at large.

Midlatitude atmospheric OH response to the most recent 11-y solar cycle.

PubMed

Wang, Shuhui; Li, King-Fai; Pongetti, Thomas J; Sander, Stanley P; Yung, Yuk L; Liang, Mao-Chang; Livesey, Nathaniel J; Santee, Michelle L; Harder, Jerald W; Snow, Martin; Mills, Franklin P

2013-02-05

The hydroxyl radical (OH) plays an important role in middle atmospheric photochemistry, particularly in ozone (O(3)) chemistry. Because it is mainly produced through photolysis and has a short chemical lifetime, OH is expected to show rapid responses to solar forcing [e.g., the 11-y solar cycle (SC)], resulting in variabilities in related middle atmospheric O(3) chemistry. Here, we present an effort to investigate such OH variability using long-term observations (from space and the surface) and model simulations. Ground-based measurements and data from the Microwave Limb Sounder on the National Aeronautics and Space Administration's Aura satellite suggest an ∼7-10% decrease in OH column abundance from solar maximum to solar minimum that is highly correlated with changes in total solar irradiance, solar Mg-II index, and Lyman-α index during SC 23. However, model simulations using a commonly accepted solar UV variability parameterization give much smaller OH variability (∼3%). Although this discrepancy could result partially from the limitations in our current understanding of middle atmospheric chemistry, recently published solar spectral irradiance data from the Solar Radiation and Climate Experiment suggest a solar UV variability that is much larger than previously believed. With a solar forcing derived from the Solar Radiation and Climate Experiment data, modeled OH variability (∼6-7%) agrees much better with observations. Model simulations reveal the detailed chemical mechanisms, suggesting that such OH variability and the corresponding catalytic chemistry may dominate the O(3) SC signal in the upper stratosphere. Continuing measurements through SC 24 are required to understand this OH variability and its impacts on O(3) further.

Midlatitude atmospheric OH response to the most recent 11-y solar cycle

PubMed Central

Wang, Shuhui; Li, King-Fai; Pongetti, Thomas J.; Sander, Stanley P.; Yung, Yuk L.; Liang, Mao-Chang; Livesey, Nathaniel J.; Santee, Michelle L.; Harder, Jerald W.; Snow, Martin; Mills, Franklin P.

2013-01-01

The hydroxyl radical (OH) plays an important role in middle atmospheric photochemistry, particularly in ozone (O3) chemistry. Because it is mainly produced through photolysis and has a short chemical lifetime, OH is expected to show rapid responses to solar forcing [e.g., the 11-y solar cycle (SC)], resulting in variabilities in related middle atmospheric O3 chemistry. Here, we present an effort to investigate such OH variability using long-term observations (from space and the surface) and model simulations. Ground-based measurements and data from the Microwave Limb Sounder on the National Aeronautics and Space Administration’s Aura satellite suggest an ∼7–10% decrease in OH column abundance from solar maximum to solar minimum that is highly correlated with changes in total solar irradiance, solar Mg-II index, and Lyman-α index during SC 23. However, model simulations using a commonly accepted solar UV variability parameterization give much smaller OH variability (∼3%). Although this discrepancy could result partially from the limitations in our current understanding of middle atmospheric chemistry, recently published solar spectral irradiance data from the Solar Radiation and Climate Experiment suggest a solar UV variability that is much larger than previously believed. With a solar forcing derived from the Solar Radiation and Climate Experiment data, modeled OH variability (∼6–7%) agrees much better with observations. Model simulations reveal the detailed chemical mechanisms, suggesting that such OH variability and the corresponding catalytic chemistry may dominate the O3 SC signal in the upper stratosphere. Continuing measurements through SC 24 are required to understand this OH variability and its impacts on O3 further. PMID:23341617

Ensemble downscaling in coupled solar wind-magnetosphere modeling for space weather forecasting

PubMed Central

Owens, M J; Horbury, T S; Wicks, R T; McGregor, S L; Savani, N P; Xiong, M

2014-01-01

Advanced forecasting of space weather requires simulation of the whole Sun-to-Earth system, which necessitates driving magnetospheric models with the outputs from solar wind models. This presents a fundamental difficulty, as the magnetosphere is sensitive to both large-scale solar wind structures, which can be captured by solar wind models, and small-scale solar wind “noise,” which is far below typical solar wind model resolution and results primarily from stochastic processes. Following similar approaches in terrestrial climate modeling, we propose statistical “downscaling” of solar wind model results prior to their use as input to a magnetospheric model. As magnetospheric response can be highly nonlinear, this is preferable to downscaling the results of magnetospheric modeling. To demonstrate the benefit of this approach, we first approximate solar wind model output by smoothing solar wind observations with an 8 h filter, then add small-scale structure back in through the addition of random noise with the observed spectral characteristics. Here we use a very simple parameterization of noise based upon the observed probability distribution functions of solar wind parameters, but more sophisticated methods will be developed in the future. An ensemble of results from the simple downscaling scheme are tested using a model-independent method and shown to add value to the magnetospheric forecast, both improving the best estimate and quantifying the uncertainty. We suggest a number of features desirable in an operational solar wind downscaling scheme. Key Points Solar wind models must be downscaled in order to drive magnetospheric models Ensemble downscaling is more effective than deterministic downscaling The magnetosphere responds nonlinearly to small-scale solar wind fluctuations PMID:26213518

SAMPIE Measurements of the Space Station Plasma Current Analyzed

NASA Technical Reports Server (NTRS)

1996-01-01

In March of 1994, STS-62 carried the NASA Lewis Research Center's Solar Array Module Plasma Interactions Experiment (SAMPIE) into orbit, where it investigated the plasma current collected and the arcs from solar arrays and other space power materials immersed in the low-Earth-orbit space plasma. One of the important experiments conducted was the plasma current collected by a four-cell coupon sample of solar array cells for the international space station. The importance of this experiment dates back to the 1990 and 1991 meetings of the Space Station Electrical Grounding Tiger Team. The Tiger Team determined that unless the electrical potentials on the space station structure were actively controlled via a plasma contactor, the space station structure would arc into the plasma at a rate that would destroy the thermal properties of its surface coatings in only a few years of operation. The space station plasma contactor will control its potentials by emitting electrons into the surrounding low-Earth-orbit plasma at the same rate that they are collected by the solar arrays. Thus, the level at which the space station solar arrays can collect current is very important in verifying that the plasma contactor design can do its job.

Introduction: Photons and ground-based

NASA Astrophysics Data System (ADS)

Spann, James; Moore, Thomas

2017-02-01

A Conference on Measurement Techniques for Solar and Space Physics was held on 20-24 April 2015 in Boulder, Colorado, at the National Center for Atmospheric Research Center Green Campus. The present volume collects together the conference papers for photons and ground-based categories.

Probabilistic Solar Energetic Particle Models

NASA Technical Reports Server (NTRS)

Adams, James H., Jr.; Dietrich, William F.; Xapsos, Michael A.

2011-01-01

To plan and design safe and reliable space missions, it is necessary to take into account the effects of the space radiation environment. This is done by setting the goal of achieving safety and reliability with some desired level of confidence. To achieve this goal, a worst-case space radiation environment at the required confidence level must be obtained. Planning and designing then proceeds, taking into account the effects of this worst-case environment. The result will be a mission that is reliable against the effects of the space radiation environment at the desired confidence level. In this paper we will describe progress toward developing a model that provides worst-case space radiation environments at user-specified confidence levels. We will present a model for worst-case event-integrated solar proton environments that provide the worst-case differential proton spectrum. This model is based on data from IMP-8 and GOES spacecraft that provide a data base extending from 1974 to the present. We will discuss extending this work to create worst-case models for peak flux and mission-integrated fluence for protons. We will also describe plans for similar models for helium and heavier ions.

Interactive Multi-Instrument Database of Solar Flares

NASA Technical Reports Server (NTRS)

Ranjan, Shubha S.; Spaulding, Ryan; Deardorff, Donald G.

2018-01-01

The fundamental motivation of the project is that the scientific output of solar research can be greatly enhanced by better exploitation of the existing solar/heliosphere space-data products jointly with ground-based observations. Our primary focus is on developing a specific innovative methodology based on recent advances in "big data" intelligent databases applied to the growing amount of high-spatial and multi-wavelength resolution, high-cadence data from NASA's missions and supporting ground-based observatories. Our flare database is not simply a manually searchable time-based catalog of events or list of web links pointing to data. It is a preprocessed metadata repository enabling fast search and automatic identification of all recorded flares sharing a specifiable set of characteristics, features, and parameters. The result is a new and unique database of solar flares and data search and classification tools for the Heliophysics community, enabling multi-instrument/multi-wavelength investigations of flare physics and supporting further development of flare-prediction methodologies.

Space-based solar power conversion and delivery systems study. Volume 1: Executive summary

NASA Technical Reports Server (NTRS)

Hazelrigg, G. A., Jr.

1976-01-01

The technical and economic aspects of satellite solar power systems are presented with a focus on the current configuration 5000 MW system. The technical studies include analyses of the orbital system structures, control and stationkeeping, and the formulation of program plans and costs for input to the economic analyses. The economic analyses centered about the development and use of a risk analysis model for a system cost assessment, identification of critical issues and technologies, and to provide information for programmatic decision making. A preliminary economic examination of some utility interface issues is included. Under the present state-of-knowledge, it is possible to formulate a program plan for the development of a satellite solar power system that can be economically justified. The key area of technological uncertainty is man's ability to fabricate and assemble large structures in space.

Collaborative observations of the Sun during ihy

NASA Astrophysics Data System (ADS)

Strong, K. T.

2003-04-01

Many of the major solar physics space missions (Solar Max, Yohkoh, SOHO, and TRACE) have feature extensive collaborative observations with ground-based observers, sounding rocket flights and other space missions. These joint observations have produced some significant results. In preparation for IHY, this poster presents some of the lessons learned from some of these collaborations. The more successful ones have a clear scientific goal and have been planned, coordinated and advertised well in advance with at least one dry run. They have generally not relied on a particular type of solar activity being present at the time of the observations or have been very flexible in the timing of the investigation. Most importantly, they have had a plan with a set schedule to follow up the observation run with data processing, analysis and modeling workshops whether it's a large group or just individual scientists.

Nuclear Energy for Space Exploration

NASA Technical Reports Server (NTRS)

Houts, Michael G.

2010-01-01

Nuclear power and propulsion systems can enable exciting space exploration missions. These include bases on the moon and Mars; and the exploration, development, and utilization of the solar system. In the near-term, fission surface power systems could provide abundant, constant, cost-effective power anywhere on the surface of the Moon or Mars, independent of available sunlight. Affordable access to Mars, the asteroid belt, or other destinations could be provided by nuclear thermal rockets. In the further term, high performance fission power supplies could enable both extremely high power levels on planetary surfaces and fission electric propulsion vehicles for rapid, efficient cargo and crew transfer. Advanced fission propulsion systems could eventually allow routine access to the entire solar system. Fission systems could also enable the utilization of resources within the solar system. Fusion and antimatter systems may also be viable in the future

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.

Geodetic Space Weather Monitoring by means of Ionosphere Modelling

NASA Astrophysics Data System (ADS)

Schmidt, Michael

2017-04-01

The term space weather indicates physical processes and phenomena in space caused by radiation of energy mainly from the Sun. Manifestations of space weather are (1) variations of the Earth's magnetic field, (2) the polar lights in the northern and southern hemisphere, (3) variations within the ionosphere as part of the upper atmosphere characterized by the existence of free electrons and ions, (4) the solar wind, i.e. the permanent emission of electrons and photons, (5) the interplanetary magnetic field, and (6) electric currents, e.g. the van Allen radiation belt. It can be stated that ionosphere disturbances are often caused by so-called solar storms. A solar storm comprises solar events such as solar flares and coronal mass ejections (CMEs) which have different effects on the Earth. Solar flares may cause disturbances in positioning, navigation and communication. CMEs can effect severe disturbances and in extreme cases damages or even destructions of modern infrastructure. Examples are interruptions to satellite services including the global navigation satellite systems (GNSS), communication systems, Earth observation and imaging systems or a potential failure of power networks. Currently the measurements of solar satellite missions such as STEREO and SOHO are used to forecast solar events. Besides these measurements the Earth's ionosphere plays another key role in monitoring the space weather, because it responses to solar storms with an increase of the electron density. Space-geodetic observation techniques, such as terrestrial GNSS, satellite altimetry, space-borne GPS (radio occultation), DORIS and VLBI provide valuable global information about the state of the ionosphere. Additionally geodesy has a long history and large experience in developing and using sophisticated analysis and combination techniques as well as empirical and physical modelling approaches. Consequently, geodesy is predestinated for strongly supporting space weather monitoring via modelling the ionosphere and detecting and forecasting its disturbances. At present a couple of nations, such as the US, UK, Japan, Canada and China, are taken the threats from extreme space weather events seriously and support the development of observing strategies and fundamental research. However, (extreme) space weather events are in all their consequences on the modern highly technologized society, causative global problems which have to be treated globally and not regionally or even nationally. Consequently, space weather monitoring must include (1) all space-geodetic observation techniques and (2) geodetic evaluation methods such as data combination, real-time modelling and forecast. In other words, geodetic space weather monitoring comprises the basic ideas of GGOS and will provide products such as forecasts of severe solar events in order to initiate necessary activities to protect the infrastructure of modern society.

Advanced In-Space Propulsion: "Exploring the Solar System"

NASA Technical Reports Server (NTRS)

Johnson, Les

2003-01-01

This viewgraph presentation reviews a number of advanced propulsion technologies for interplanetary spacecraft. The objective of the In Space Propulsion Technology Projects Office is to develop in-space propulsion technologies that can enable and/or benefit near and mid-term NASA science missions by significantly reducing cost, mass, and/or travel times. The technologies profiled are divided into several categories: High Priority (aerocapture, next generation ion propulsion, solar sails); Medium Priority (advanced chemical propulsion, solar electric propulsion, Hall thrusters); Low Priority (solar thermal propulsion); and High Payoff/High Risk (1 g/sq m solar sails, momentum exchange tethers, and plasma sails).