Radiation Processing of Polycyclic Aromatic Hydrocarbons (PAHs) in Space: ICEE PoC

NASA Technical Reports Server (NTRS)

Mattioda, Andrew; Cruz-Diaz, Gustavo; Barnhardt, Michael; Ging, Andrew; Schneider, Todd; Vaughn, Jason; Quigley, Emmett; Phillips, Brandon

2017-01-01

Small Polycyclic Aromatic Hydrocarbon molecules or PAHs (<30 carbon atoms) have been identified in comets, meteorites, asteroids, and interplanetary dust particles in our Solar System, while PAHs in the Interstellar Medium (ISM) tend to be much larger, usually between 50 to 100 carbon atoms in size. The cause of the size disparity between PAHs found in the ISM and Solar System as well as their influence on Solar System organics is not yet understood. Two chemical evolutionary paths have been proposed to explain the inventory of solar system organics. In one the prebiotic material was formed from the radiation induced modification of large pre-solar carbon-bearing species (e.g. ISM PAHs). The second path suggests that Solar System prebiotic matter is the result of bottom-up synthesis from small reactive molecules after the Solar System was formed. In this second scenario very few ISM PAHs survived the harsh pre-solar radiation as aromatic structures. ICEE PoC (ICEE Proof of Concept) investigated factors impacting the chemical evolution of large PAHs irradiated under conditions similar to the proto-solar nebula. Likewise ICEE PoC will refine the technical parameters of the proposed ICEE (Institute for Carbon Evolution Experiment) laboratory.

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.

Solar Thermal Small Power Systems Study. Inventory of US industrial small electric power generating systems. [Less than 10 MW

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

Not Available

This inventory of small industrial electric generating systems was assembled by The Aerospace Corporation to provide a data base for analyses being conducted to estimate the potential for displacement of these fossil-fueled systems by solar thermal electric systems no larger than 10 MW in rated capacity. The approximately 2100 megawatts generating capacity of systems in this category constitutes a potential market for small solar thermal and other solar electric power systems. The sources of data for this inventory were the (former) Federal Power Commission (FPC) Form 4 Industrial Ledger and Form 12-C Ledger for 1976. Table 1 alphabetically lists generatingmore » systems located at industrial plants and at Federal government installations in each of the 50 states. These systems are differentiated by type of power plant: steam turbine, diesel generator, or gas turbine. Each listing is designated as a power system rather than a power unit because the FPC Ledgers do not provide a means of determining whether more than one unit is associated with each industrial installation. Hence, the user should consider each listing to be a system capacity rating wherein the system may consist of one or more generating units with less than 10 MW/sub e/ combined rating. (WHK)« less

Life Cycle Cost of Solar Biomass Hybrid Dryer Systems for Cashew Drying of Nuts in India

NASA Astrophysics Data System (ADS)

Dhanushkodi, Saravanan; Wilson, Vincent H.; Sudhakar, Kumarasamy

2015-12-01

Cashew nut farming in India is mostly carried out in small and marginal holdings. Energy consumption in the small scale cashew nut processing industry is very high and is mainly due to the high energy consumption of the drying process. The drying operation provides a lot of scope for energy saving and substitutions of other renewable energy sources. Renewable energy-based drying systems with loading capacity of 40 kg were proposed for application in small scale cashew nut processing industries. The main objective of this work is to perform economic feasibility of substituting solar, biomass and hybrid dryer in place of conventional steam drying for cashew drying. Four economic indicators were used to assess the feasibility of three renewable based drying technologies. The payback time was 1.58 yr. for solar, 1.32 for biomass and 1.99 for the hybrid drying system, whereas as the cost-benefit estimates were 5.23 for solar, 4.15 for biomass and 3.32 for the hybrid system. It was found that it is of paramount importance to develop solar biomass hybrid dryer for small scale processing industries.

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.

Solar thermal power plants in small utilities - An economic impact analysis

NASA Technical Reports Server (NTRS)

Bluhm, S. A.; Ferber, R. R.; Mayo, L. G.

1979-01-01

A study was performed to assess the potential economic impact of small solar thermal electric power systems in statistically representative synthetic small utilities of the Southwestern United States. Power supply expansion plans were compared on the basis of present worth of future revenue requirements for 1980-2000 with and without solar thermal plants. Coal-fired and oil-fired municipal utility expansion plans with 5 percent solar penetration were 0.5 percent and 2.25 percent less expensive, respectively, than the corresponding conventional plan. At $969/kWe, which assumes the same low cost solar equipment but no improvement in site development costs, solar penetration of 5 percent in the oil-fired municipal reduced revenue requirements 0.88 percent. The paper concludes that some solar thermal plants are potentially economic in small community utilities of the Southwest.

Small Scale Solar Cooling Unit in Climate Conditions of Latvia: Environmental and Economical Aspects

NASA Astrophysics Data System (ADS)

Jaunzems, Dzintars; Veidenbergs, Ivars

2010-01-01

The paper contributes to the analyses from the environmental and economical point of view of small scale solar cooling system in climate conditions of Latvia. Cost analyses show that buildings with a higher cooling load and full load hours have lower costs. For high internal gains, cooling costs are around 1,7 €/kWh and 2,5 €/kWh for buildings with lower internal gains. Despite the fact that solar cooling systems have significant potential to reduce CO2 emissions due to a reduction of electricity consumption, the economic feasibility and attractiveness of solar cooling system is still low.

Selection and development of small solar thermal power applications

NASA Technical Reports Server (NTRS)

Bluhm, S. A.; Kuehn, T. J.; Gurfield, R. M.

1979-01-01

The paper discusses the approach of the JPL Point Focusing Thermal and Electric Power Applications Project to selecting and developing applications for point-focusing distributed-receiver solar thermal electric power systems. Six application categories are defined. Results of application studies of U.S. utilities are presented. The economic value of solar thermal power systems was found to range from $900 to $2100/kWe in small community utilities of the Southwest.

Small Body Exploration Technologies as Precursors for Interstellar Robotics

NASA Astrophysics Data System (ADS)

Noble, R. J.; Sykes, M. V.

The scientific activities undertaken to explore our Solar System will be very similar to those required someday at other stars. The systematic exploration of primitive small bodies throughout our Solar System requires new technologies for autonomous robotic spacecraft. These diverse celestial bodies contain clues to the early stages of the Solar System's evolution, as well as information about the origin and transport of water-rich and organic material, the essential building blocks for life. They will be among the first objects studied at distant star systems. The technologies developed to address small body and outer planet exploration will form much of the technical basis for designing interstellar robotic explorers. The Small Bodies Assessment Group, which reports to NASA, initiated a Technology Forum in 2011 that brought together scientists and technologists to discuss the needs and opportunities for small body robotic exploration in the Solar System. Presentations and discussions occurred in the areas of mission and spacecraft design, electric power, propulsion, avionics, communications, autonomous navigation, remote sensing and surface instruments, sampling, intelligent event recognition, and command and sequencing software. In this paper, the major technology themes from the Technology Forum are reviewed, and suggestions are made for developments that will have the largest impact on realizing autonomous robotic vehicles capable of exploring other star systems.

Small Body Exploration Technologies as Precursors for Interstellar Robotics

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

Noble, Robert; /SLAC; Sykes, Mark V.

The scientific activities undertaken to explore our Solar System will be the same as required someday at other stars. The systematic exploration of primitive small bodies throughout our Solar System requires new technologies for autonomous robotic spacecraft. These diverse celestial bodies contain clues to the early stages of the Solar System's evolution as well as information about the origin and transport of water-rich and organic material, the essential building blocks for life. They will be among the first objects studied at distant star systems. The technologies developed to address small body and outer planet exploration will form much of themore » technical basis for designing interstellar robotic explorers. The Small Bodies Assessment Group, which reports to NASA, initiated a Technology Forum in 2011 that brought together scientists and technologists to discuss the needs and opportunities for small body robotic exploration in the Solar System. Presentations and discussions occurred in the areas of mission and spacecraft design, electric power, propulsion, avionics, communications, autonomous navigation, remote sensing and surface instruments, sampling, intelligent event recognition, and command and sequencing software. In this paper, the major technology themes from the Technology Forum are reviewed, and suggestions are made for developments that will have the largest impact on realizing autonomous robotic vehicles capable of exploring other star systems.« less

Small Satellite Constellations for Geospace Sciences

NASA Astrophysics Data System (ADS)

Spence, H. E.

2016-12-01

The recent National Academy of Sciences Solar and Space Physics Decadal Survey (DS) identified community-consensus science priorities for the decade spanning 2013 - 2022. In this talk, we discuss the ways by which small satellite constellations are already and may soon accelerate progress toward achieving many of these science targets. The DS outlined four overarching science goals: (1) determine the origins of the Sun's activity and predict the variations in the space environment; (2) determine the dynamics and coupling of Earth's magnetosphere, ionosphere, and atmosphere and their response to solar and terrestrial inputs; (3) determine the interaction of the Sun with the solar system and the interstellar medium; and, (4) discover and characterize fundamental processes that occur both within the heliosphere and throughout the universe. These DS science goals provide the context for key science challenges in the three connected parts of the system that encompass all of solar and space physics, herein referred to as geospace: the Sun and heliosphere; the coupled solar wind-magnetosphere system; and, the coupled atmosphere-ionosphere-magnetosphere system. The DS further presented the role that small satellites play in resolving many of these science challenges, with a particular emphasis on the role that constellations of small satellites will play. While once considered by many as being "futuristic" or even "unrealizable", constellations of small satellites are already making important contributions to geospace science and with the promise for more to come. Using the DS as a guidepost, in this presentation, we outline representative small satellite constellation missions alread underway, some in development, and others notionally proposed over the next several years that employ small satellite constellations to tackle large science imperatives. Finally, we give examples of key small satellite technologies in development that will potentially enable great scientific return with comparatively low investments in small satellite missions.

Powering a Home with Just 25 Watts of Solar PV. Super-Efficient Appliances Can Enable Expanded Off-Grid Energy Service Using Small Solar Power Systems

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

Phadke, Amol A.; Jacobson, Arne; Park, Won Young

Highly efficient direct current (DC) appliances have the potential to dramatically increase the affordability of off-grid solar power systems used for rural electrification in developing countries by reducing the size of the systems required. For example, the combined power requirement of a highly efficient color TV, four DC light emitting diode (LED) lamps, a mobile phone charger, and a radio is approximately 18 watts and can be supported by a small solar power system (at 27 watts peak, Wp). Price declines and efficiency advances in LED technology are already enabling rapidly increased use of small off-grid lighting systems in Africamore » and Asia. Similar progress is also possible for larger household-scale solar home systems that power appliances such as lights, TVs, fans, radios, and mobile phones. When super-efficient appliances are used, the total cost of solar home systems and their associated appliances can be reduced by as much as 50%. The results vary according to the appliances used with the system. These findings have critical relevance for efforts to provide modern energy services to the 1.2 billion people worldwide without access to the electrical grid and one billion more with unreliable access. However, policy and market support are needed to realize rapid adoption of super-efficient appliances.« less

Phase Curves of Nix and Hydra from the New Horizons Imaging Cameras

NASA Astrophysics Data System (ADS)

Verbiscer, Anne J.; Porter, Simon B.; Buratti, Bonnie J.; Weaver, Harold A.; Spencer, John R.; Showalter, Mark R.; Buie, Marc W.; Hofgartner, Jason D.; Hicks, Michael D.; Ennico-Smith, Kimberly; Olkin, Catherine B.; Stern, S. Alan; Young, Leslie A.; Cheng, Andrew; (The New Horizons Team

2018-01-01

NASA’s New Horizons spacecraft’s voyage through the Pluto system centered on 2015 July 14 provided images of Pluto’s small satellites Nix and Hydra at viewing angles unattainable from Earth. Here, we present solar phase curves of the two largest of Pluto’s small moons, Nix and Hydra, observed by the New Horizons LOng Range Reconnaissance Imager and Multi-spectral Visible Imaging Camera, which reveal the scattering properties of their icy surfaces in visible light. Construction of these solar phase curves enables comparisons between the photometric properties of Pluto’s small moons and those of other icy satellites in the outer solar system. Nix and Hydra have higher visible albedos than those of other resonant Kuiper Belt objects and irregular satellites of the giant planets, but not as high as small satellites of Saturn interior to Titan. Both Nix and Hydra appear to scatter visible light preferentially in the forward direction, unlike most icy satellites in the outer solar system, which are typically backscattering.

Orbit Mechanics about Small Asteroids

NASA Technical Reports Server (NTRS)

Scheeres, D. J.

2007-01-01

Space missions to small solar system bodies must deal with multiple perturbations acting on the spacecraft. These include strong perturbations from the gravity field and solar tide, but for small bodies the most important perturbations may arise from solar radiation pressure (SRP) acting on the spacecraft. Previous research has generally investigated the effect of the gravity field, solar tide, and SRP acting on a spacecraft trajectory about an asteroid in isolation and has not considered their joint effect. In this paper a more general theoretical discussion of the joint effects of these forces is given.

JPL - Small Power Systems Applications Project. [for solar thermal power plant development and commercialization

NASA Technical Reports Server (NTRS)

Ferber, R. R.; Marriott, A. T.; Truscello, V.

1978-01-01

The Small Power Systems Applications (SPSA) Project has been established to develop and commercialize small solar thermal power plants. The technologies of interest include all distributed and central receiver technologies which are potentially economically viable in power plant sizes of one to 10 MWe. The paper presents an overview of the SPSA Project and briefly discusses electric utility involvement in the Project.

Application of small-signal modeling and measurement techniques to the stability analysis of an integrated switching-mode power system. [onboard Dynamics Explorer Satellite

NASA Technical Reports Server (NTRS)

Wong, R. C.; Owen, H. A., Jr.; Wilson, T. G.; Rodriguez, G. E.

1980-01-01

Small-signal modeling techniques are used in a system stability analysis of a breadboard version of a complete functional electrical power system. The system consists of a regulated switching dc-to-dc converter, a solar-cell-array simulator, a solar-array EMI filter, battery chargers and linear shunt regulators. Loss mechanisms in the converter power stage, including switching-time effects in the semiconductor elements, are incorporated into the modeling procedure to provide an accurate representation of the system without requiring frequency-domain measurements to determine the damping factor. The small-signal system model is validated by the use of special measurement techniques which are adapted to the poor signal-to-noise ratio encountered in switching-mode systems. The complete electrical power system with the solar-array EMI filter is shown to be stable over the intended range of operation.

Electrical design for origami solar panels and a small spacecraft test mission

NASA Astrophysics Data System (ADS)

Drewelow, James; Straub, Jeremy

2017-05-01

Efficient power generation is crucial to the design of spacecraft. Mass, volume, and other limitations prevent the use of traditional spacecraft support structures from being suitable for the size of solar array required for some missions. Folding solar panel / panel array systems, however, present a number of design challenges. This paper considers the electrical design of an origami system. Specifically, it considers how to provide low impedance, durable channels for the generated power and the electrical aspects of the deployment system and procedure. The ability to dynamically reconfigure the electrical configuration of the solar cells is also discussed. Finally, a small satellite test mission to demonstrate the technology is proposed, before concluding.

Developing a hybrid solar/wind powered irrigation system for crops in the Great Plains

USDA-ARS?s Scientific Manuscript database

Some small scale irrigation systems (< 2 ha) powered by wind or solar do not require subsidies, but this paper discusses ways to achieve an economical renewable energy powered center pivot irrigation system for crops in the Great Plains. By adding a solar-photovoltaic (PV) array together with a wind...

K2 & Solar System Science

NASA Technical Reports Server (NTRS)

Lissauer, Jack

2015-01-01

All of the fields that K2 observes are near the ecliptic plane in order to minimize the spin-up of the spacecraft in response to the effects of solar irradiation. The fields observed by K2 are thus rich in Solar System objects including planets, asteroids and trans-Neptunian objects (TNOs). K2 has already performed observations of Neptune and its large moon Triton, 68 Trojan and Hilda asteroids, 5 TNOs (including Pluto) and Comet C/2013 A1 (Siding Springs). About 10,000 main-belt asteroids that fell into the pixel masks of stars have been serendipitously observed. Observations of small bodies are especially useful for determining rotation periods. Uranus will be observed in a future campaign (C8), as will many more small Solar System bodies. The status of various K2 Solar System studies will be reviewed and placed within the context of our current knowledge of the objects being observed.

Solar Energy and Other Appropriate Technologies for Small ...

EPA Pesticide Factsheets

This Region 2 research demonstration project presentation studied the efficacy of sustainable solar-powered water delivery and monitoring systems to reduce the economic burden of operating and maintaining Non-PRASA drinking water systems and to reduce the impact of climate change resulting from the use of fossil fuels in Puerto Rico. In Puerto Rico, petroleum (65%), natural gas (18%) and coal (16%) are imported to generate electricity resulting in electrical rates that are more than twice the US average. In 2012, only 1% of electricity came from renewable energy (US Energy Information Administration). One major cost for electricity for small communities in Puerto Rico is the transfer, treatment and distribution of drinking water. These small communities (Non-PRASA communities) are not able to afford electrical costs and many have abandoned their groundwater sources and reverted to unfiltered surface water systems, creating serious public health risks and non-compliance. Many Non-PRASA groundwater systems (141 out of 247) could use solar-powered pumps to extract and deliver groundwater. Solar power would also extend the life of system electrical components by improving the quality of electrical power supply. Solar power as a renewable energy source for Non-PRASA water systems is a viable approach that also reduces the impact of climate change in the Caribbean.

Proceedings of Small Power Systems Solar Electric Workshop. Volume 2: Invited papers

NASA Technical Reports Server (NTRS)

Ferber, R. (Editor)

1978-01-01

The focus of this work shop was to present the committment to the development of solar thermal power plants for a variety of applications including utility applications. Workshop activities included panel discussions, formal presentations, small group interactive discussions, question and answer periods, and informal gatherings. Discussion on topics include: (1) solar power technology options; (2) solar thermal power programs currently underway at the DOE, JPL, Electric Power Research Institute (EPRI), and Solar Energy Research Institute (SERI); (3) power options competing with solar; (4) institutional issues; (5) environmental and siting issues; (6) financial issues; (7) energy storage; (8) site requirements for experimental solar installations, and (9) utility planning.

System design package for SIMS prototype system 4, solar heating and domestic hot water

NASA Technical Reports Server (NTRS)

1978-01-01

The system consisted of a modular designed prepackaged solar unit, containing solar collectors, a rock storage container, blowers, dampers, ducting, air-to-water heat exchanger, DHW preheat tank, piping, and system controls. The system was designed to be installed adjacent to a small single family dwelling. The description, performance specification, subsystem drawings, verification plan/procedure, and hazard analysis of the system were packaged for evaluation.

Phase 1 of the First Small Power System Experiment (engineering Experiment No. 1). Volume 4: Commercial System Definition. [development and testing of a solar thermal power plant

NASA Technical Reports Server (NTRS)

Holl, R. J.

1979-01-01

The development and design of a modular solar thermal power system for application in the 1 to 10 MWe range is described. The system is used in remote utility applications, small communities, rural areas, and for industrial uses. The operational reliability, the minimum risk of failure, and the maintenance and repair characteristics are determined and the commercial system design is defined.

Long-Lived In-Situ Solar System Explorer (LLISSE)

NASA Technical Reports Server (NTRS)

Kremic, Tibor; Hunter, Gary; Rock, Jennifer

2017-01-01

This presentation provides an update on development of the Long-Lived In-situ Solar System Explorer (LLISSE). LLISSE is a small probe being developed to provide long-term measurements of simple but important scientific parameters from the surface of Venus. High level summary of recent activities and progress is provided. LLISSE is a small and completely independent probe for Venus surface applications

Search for water and life's building blocks in the universe: A summary

NASA Astrophysics Data System (ADS)

Ehrenfreund, Pascale; Kwok, Sun; Bergin, Edwin

2015-08-01

Water and organic compounds are essential ingredients for life on Earth and possibly elsewhere. In gaseous form water acts as a coolant that allows interstellar gas clouds to collapse to form stars, whereas water ice covers small dust particles that agglomerate to form planetesimals and planets. The variety of organic compounds identified in interstellar and circumstellar regions reflects complex reaction schemes in the gaseous and icy/solid state. Interstellar volatiles and refractory materials were processed and radially mixed within the protostellar disk from which our solar system formed. But the dynamic solar nebula was also a source for new materials and the search for water and life’s building blocks on terrestrial planets, most of the outer-solar-system satellites as well as small solar system bodies reveals exciting new findings. The analysis of small bodies and their fragments, meteorites and interplanetary dust particles, sheds lights onto the extraterrestrial delivery process of prebiotic molecules to young planets and the pathways to life’s origin on Earth and possibly elsewhere. We summarize the results of invited and contributed papers of this Focus Meeting which will allow us to better assess the habitability of objects in our solar system and provide constraints for exoplanets.

Phase 1 of the First Solar Small Power System Experiment (experimental System No. 1). Volume 3: Appendix E - N

NASA Technical Reports Server (NTRS)

Clark, T. B. (Editor)

1979-01-01

The design of a solar electric power plant for a small community is reported. Topics covered include: (1) control configurations and interface requirements for the baseline power system; (2) annual small power system output; (3) energy requirements for operation of the collectors and control building; (4) life cycle costs and reliability predictions; (5) thermal conductivities and costs of receiver insulation materials; (6) transient thermal modelling for the baseline receiver/thermal transport system under normal and inclement operating conditions; (7) high temperature use of sodium; (8) shading in a field of parabolic collectors; and (9) buffer storage materials.

Advanced Deployable Shell-Based Composite Booms for Small Satellite Structural Applications Including Solar Sails

NASA Technical Reports Server (NTRS)

Fernandez, Juan M.

2017-01-01

State of the art deployable structures are mainly being designed for medium to large size satellites. The lack of reliable deployable structural systems for low cost, small volume, rideshare-class spacecraft severely constrains the potential for using small satellite platforms for affordable deep space science and exploration precursor missions that could be realized with solar sails. There is thus a need for reliable, lightweight, high packaging efficiency deployable booms that can serve as the supporting structure for a wide range of small satellite systems including solar sails for propulsion. The National Air and Space Administration (NASA) is currently investing in the development of a new class of advanced deployable shell-based composite booms to support future deep space small satellite missions using solar sails. The concepts are being designed to: meet the unique requirements of small satellites, maximize ground testability, permit the use of low-cost manufacturing processes that will benefit scalability, be scalable for use as elements of hierarchical structures (e.g. trusses), allow long duration storage, have high deployment reliability, and have controlled deployment behavior and predictable deployed dynamics. This paper will present the various rollable boom concepts that are being developed for 5-20 m class size deployable structures that include solar sails with the so-called High Strain Composites (HSC) materials. The deployable composite booms to be presented are being developed to expand the portfolio of available rollable booms for small satellites and maximize their length for a given packaged volume. Given that solar sails are a great example of volume and mass optimization, the booms were designed to comply with nominal solar sail system requirements for 6U CubeSats, which are a good compromise between those of smaller form factors (1U, 2U and 3U CubeSats) and larger ones (12 U and 27 U future CubeSats, and ESPA-class microsatellites). Solar sail missions for such composite boom systems are already under consideration and development at NASA, as well as mission studies that will benefit from planned scaled-up versions of the composite boom technologies to be introduced. The paper presents ongoing research and development of thin-shell rollable composite booms designed under the particular stringent and challenging system requirements of relatively large solar sails housed on small satellites. These requirements will be derived and listed. Several new boom concepts are proposed and other existing ones are improved upon using thin-ply composite materials to yield unprecedented compact deployable structures. Some of these booms are shown in Fig. 1. For every boom to be introduced the scalable fabrication process developed to keep the overall boom system cost down will be shown. Finally, the initial results of purposely designed boom structural characterization test methods with gravity off-loading will be presented to compare their structural performance under expected and general load cases.

Jovian Small Orbiter for Magnetospheric and Auroral Studies

NASA Astrophysics Data System (ADS)

Takashima, T.; Kasaba, Y.; Misawa, H.; Kawaguchi, J.

2005-12-01

Solar-Sail Project to have been examined by ISAS/JAXA as an engineering mission has a possibility of a small probe into the Jovian orbit. This paper summarizes the basic design of Jovian magnetospheric and auroral studies by this small chance. The large-scale Jovian mission has been a hope since the 1970s when the examinations of planetary exploration were started in Japan. In the one of plans, the largest planet in the solar system would be solved by two main objectives: (1) Structure of a gas planet: the internal & atmospheric structures of a gas planet which could not become a star (following the objectives of Planet-C and BepiColombo). (2) Jovian-type magnetosphere: the process of a pulsar-like magnetosphere with the strongest magnetospheric activities in the solar system (following the objectives of BepiColombo and SCOPE). The small polar-orbit orbiter in Solar-Sail Project aims to establish the feasibility of such future outer planet missions by ISAS/JAXA. It aims the former target in its limited resources.

Instability timescale for the inclination instability in the solar system

NASA Astrophysics Data System (ADS)

Zderic, Alexander; Madigan, Ann-Marie; Fleisig, Jacob

2018-04-01

The gravitational influence of small bodies is often neglected in the study of solar system dynamics. However, this is not always an appropriate assumption. For example, mutual secular torques between low mass particles on eccentric orbits can result in a self-gravity instability (`inclination instability'; Madigan & McCourt 2016). During the instability, inclinations increase exponentially, eccentricities decrease (detachment), and orbits cluster in argument of perihelion. In the solar system, the orbits of the most distant objects show all three of these characteristics (high inclination: Volk & Malhotra (2017), detachment: Delsanti & Jewitt (2006), and argument of perihelion clustering: Trujillo & Sheppard (2014)). The inclination instability is a natural explanation for these phenomena.Unfortunately, full N-body simulations of the solar system are unfeasible (N ≈ O(1012)), and the behavior of the instability depends on N, prohibiting the direct application of lower N simulations. Here we present the instability timescale's functional dependence on N, allowing us to extrapolate our simulation results to that appropriate for the solar system. We show that ~5 MEarth of small icy bodies in the Sedna region is sufficient for the inclination instability to occur in the outer solar system.

Exploring small bodies in the outer solar system with stellar occultations

NASA Technical Reports Server (NTRS)

Elliot, Jim L.; Dunham, Edward W.; Olkin, C. B.

1995-01-01

Stellar occultation observations probe the atmospheric structure and extinction of outer solar system bodies with a spatial resolution of a few kilometers, and an airborne platform allows the observation of occultations by small bodies that are not visible from fixed telescopes. Results from occultations by Triton, Pluto, and Chiron observed with KAO are discussed, and future directions for this program are presented.

Reliability and cost/worth evaluation of generating systems utilizing wind and solar energy

NASA Astrophysics Data System (ADS)

Bagen

The utilization of renewable energy resources such as wind and solar energy for electric power supply has received considerable attention in recent years due to adverse environmental impacts and fuel cost escalation associated with conventional generation. At the present time, wind and/or solar energy sources are utilized to generate electric power in many applications. Wind and solar energy will become important sources for power generation in the future because of their environmental, social and economic benefits, together with public support and government incentives. The wind and sunlight are, however, unstable and variable energy sources, and behave far differently than conventional sources. Energy storage systems are, therefore, often required to smooth the fluctuating nature of the energy conversion system especially in small isolated applications. The research work presented in this thesis is focused on the development and application of reliability and economic benefits assessment associated with incorporating wind energy, solar energy and energy storage in power generating systems. A probabilistic approach using sequential Monte Carlo simulation was employed in this research and a number of analyses were conducted with regards to the adequacy and economic assessment of generation systems containing wind energy, solar energy and energy storage. The evaluation models and techniques incorporate risk index distributions and different operating strategies associated with diesel generation in small isolated systems. Deterministic and probabilistic techniques are combined in this thesis using a system well-being approach to provide useful adequacy indices for small isolated systems that include renewable energy and energy storage. The concepts presented and examples illustrated in this thesis will help power system planners and utility managers to assess the reliability and economic benefits of utilizing wind energy conversion systems, solar energy conversion systems and energy storage in electric power systems and provide useful input to the managerial decision process.

Phase 1 of the First Solar Small Power System Experiment (experimental System No. 1). Volume 1: Technical Studies for Solar Point-focusing, Distributed Collector System, with Energy Conversion at the Collector, Category C

NASA Technical Reports Server (NTRS)

Clark, T. B. (Editor)

1979-01-01

The technical and economic feasibility of a solar electric power plant for a small community is evaluated and specific system designs for development and demonstration are selected. All systems investigated are defined as point focusing, distributed receiver concepts, with energy conversion at the collector. The preferred system is comprised of multiple parabolic dish concentrators employing Stirling cycle engines for power conversion. The engine, AC generator, cavity receiver, and integral sodium pool boiler/heat transport system are combined in a single package and mounted at the focus of each concentrator. The output of each concentrator is collected by a conventional electrical distribution system which permits grid-connected or stand-alone operation, depending on the storage system selected.

Radiation forces on small particles in the solar system

NASA Technical Reports Server (NTRS)

Burns, J. A.; Lamy, P. L.; Soter, S.

1979-01-01

Solar radiation forces on small particles in the solar system are examined, and the resulting orbital evolution of interplanetary and circumplanetary dust is considered. An expression is derived for the effects of radiation pressure and Poynting-Robertson drag on small, spherical particles using the energy and momentum transformation laws of special relativity, and numerical examples are presented to illustrate that radiation pressure and Poynting-Robertson drag are only important for particles within a narrow size range. The orbital consequences of these radiation forces are considered both for heliocentric and planetocentric orbiting particles, and the coupling between particle sizes and dynamics is discussed. A qualitative derivation is presented for the differential Doppler effect, which is due to the differential Doppler shifting of radiation from approaching and receding solar hemispheres, and the Yarkovsky effect, which is important for rotating meter-to kilometer-sized particles, is briefly described.

Meteoroids: The Smallest Solar System Bodies

NASA Technical Reports Server (NTRS)

Moser, Danielle E. (Compiler); Hardin, B. F. (Compiler); Janches, Diego (Compiler)

2011-01-01

This volume is a compilation of articles reflecting the current state of knowledge on the physics, chemistry, astronomy, and aeronomy of small bodies in the solar system. The articles included here represent the most recent results in meteor, meteoroid, and related research fields and were presented May 24-28, 2010, in Breckenridge, Colorado, USA at Meteoroids 2010: An International Conference on Minor Bodies in the Solar System.

Papaya drying and waste conversion system. Final report

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

Not Available

1982-02-12

This project, performed under United States Department of Energy Small-scale Appropriate Energy Technology Grant, involves demonstration of an integrated system using solar energy to process off-grade or reject fruit into marketable food products. The integrated system consists of three phases: (1) solar dehydration of usable fruit; (2) solar vacuum distillation of fermented wastes (peelings, rinds, skins, and seeds) to produce an ethanol fuel to use as a backup source of heat for dehydration; and (3) land reclamation by mixing stillage and compost with volcanic cinder and ash to produce on marginal land a rich soil suitable for growing more cropsmore » to dry. Although the system is not 100% complete the investigators have demonstrated that a small business can efficiently use solar energies in an integrated fashion to process waste into food, improve the quality of the land, and provide meaningful jobs in a region of very high unemployment.« less

Sample Return from Small Solar System Bodies

NASA Astrophysics Data System (ADS)

Orgel, L.; A'Hearn, M.; Bada, J.; Baross, J.; Chapman, C.; Drake, M.; Kerridge, J.; Race, M.; Sogin, M.; Squyres, S.

With plans for multiple sample return missions in the next decade, NASA requested guidance from the National Research Council's SSB on how to treat samples returned from solar system bodies such as planetary satellites, asteroids and comets. A special Task Group assessed the potential for a living entity to be included in return samples from various bodies as well as the potential for large scale effects if such an entity were inadvertently introduced into the Earth's biosphere. The Group also assessed differences among solar system bodies, identified investigations that could reduce uncertainty about the bodies, and considered risks of returned samples compared to natural influx of material to the Earth in the form of interplanetary dust particles, meteorites and other small impactors. The final report (NRC, 1998) provides a decision making framework for future missions and makes recommendations on how to handle samples from different planetary satellites and primitive solar system bodies

Structure and evolutionary history of the solar system

NASA Technical Reports Server (NTRS)

Alfven, H.; Arrhenius, G.

1975-01-01

General principles and observational facts concerning the solar system are examined, taking into account the orbits of planets and satellites, the small bodies, the resonance structure, spin and tides, and postaccretional changes in the solar system. A description is given of the accretion of celestial bodies and the plasma phase is considered. Aspects of chemical differentiation and the matrix of the groups of bodies are also discussed, giving attention to chemical compositions in the solar system, meteorites and their precursor states, mass distribution and the critical velocity, and the structure of the groups.

Asteroid-comet continuum objects in the solar system.

PubMed

Hsieh, Henry H

2017-07-13

In this review presented at the Royal Society meeting, 'Cometary science after Rosetta', I present an overview of studies of small solar system objects that exhibit properties of both asteroids and comets (with a focus on so-called active asteroids). Sometimes referred to as 'transition objects', these bodies are perhaps more appropriately described as 'continuum objects', to reflect the notion that rather than necessarily representing actual transitional evolutionary states between asteroids and comets, they simply belong to the general population of small solar system bodies that happen to exhibit a continuous range of observational, physical and dynamical properties. Continuum objects are intriguing because they possess many of the properties that make classical comets interesting to study (e.g. relatively primitive compositions, ejection of surface and subsurface material into space where it can be more easily studied, and orbital properties that allow us to sample material from distant parts of the solar system that would otherwise be inaccessible), while allowing us to study regions of the solar system that are not sampled by classical comets.This article is part of the themed issue 'Cometary science after Rosetta'. © 2017 The Author(s).

Momentum Management for the NASA Near Earth Asteroid Scout Solar Sail Mission

NASA Technical Reports Server (NTRS)

Heaton, Andrew; Diedrich, Benjamin L.; Orphee, Juan; Stiltner, Brandon; Becker, Christopher

2017-01-01

The Momentum Management (MM) system is described for the NASA Near Earth Asteroid Scout (NEA Scout) cubesat solar sail mission. Unlike many solar sail mission proposals that used solar torque as the primary or only attitude control system, NEA Scout uses small reaction wheels (RW) and a reaction control system (RCS) with cold gas thrusters, as described in the abstract "Solar Sail Attitude Control System for Near Earth Asteroid Scout Cubesat Mission." The reaction wheels allow fine pointing and higher rates with low mass actuators to meet the science, communication, and trajectory guidance requirements. The MM system keeps the speed of the wheels within their operating margins using a combination of solar torque and the RCS.

Surface elements and landing strategies for small bodies missions - Philae and beyond

NASA Astrophysics Data System (ADS)

Ulamec, Stephan; Biele, Jens

2009-10-01

The investigation of small bodies, comets and asteroids, can contribute substantially to our understanding of the formation and history of the Solar System. In-situ observations by Landers play a prominent role in this field. The Rosetta Lander - Philae - is currently on its way to comet 67P/Churyumov-Gerasimenko. It will land in November 2014 and perform numerous experiments with a suite of 10 scientific instruments. Philae has been designed to cope with a wide range of possible comet properties. The considerations taken during its development are relevant for future Lander missions to small bodies in the Solar System. In addition the paper provides a review of alternative concepts, studied or developed for various missions like Phobos, Hayabusa/Minerva or Géocroiseur/Leonard. Various missions to small bodies in the Solar System, including Landers, are currently studied (e.g., Marco Polo). The paper will address the mission options and compare applicable technologies with the solutions chosen for Philae.

Phase 1 of the First Small Power System Experiment (engineering Experiment No. 1). Volume 5: Supporting Analyses and Trade Studies. [development and testing of a solar thermal power plant

NASA Technical Reports Server (NTRS)

Holl, R. J.

1979-01-01

The development and design of a modular solar thermal power system for application in the 1 to 10 MWe range is described. The system is used in remote utility applications, small communities, rural areas, and for industrial uses. Thermal and stress analyses are performed on the collector subsystem, energy storage subsystem, energy transport subsystem, the power conversion subsystem, and the plant control subsystem.

Solar power satellite system definition study. Volume 5: Space transportation analysis, phase 3

NASA Technical Reports Server (NTRS)

1980-01-01

A small Heavy Lift Launch Vehicle (HLLV) for the Solar Power Satellites (SPS) System was analyzed. It is recommended that the small HLLV with a payload of 120 metric tons be adopted as the SPS launch vehicle. The reference HLLV, a shuttle-derived option with a payload of 400 metric tons, should serve as a backup and be examined further after initial flight experience. The electric orbit transfer vehicle should be retained as the reference orbit-to-orbit cargo system.

Key techniques for space-based solar pumped semiconductor lasers

NASA Astrophysics Data System (ADS)

He, Yang; Xiong, Sheng-jun; Liu, Xiao-long; Han, Wei-hua

2014-12-01

In space, the absence of atmospheric turbulence, absorption, dispersion and aerosol factors on laser transmission. Therefore, space-based laser has important values in satellite communication, satellite attitude controlling, space debris clearing, and long distance energy transmission, etc. On the other hand, solar energy is a kind of clean and renewable resources, the average intensity of solar irradiation on the earth is 1353W/m2, and it is even higher in space. Therefore, the space-based solar pumped lasers has attracted much research in recent years, most research focuses on solar pumped solid state lasers and solar pumped fiber lasers. The two lasing principle is based on stimulated emission of the rare earth ions such as Nd, Yb, Cr. The rare earth ions absorb light only in narrow bands. This leads to inefficient absorption of the broad-band solar spectrum, and increases the system heating load, which make the system solar to laser power conversion efficiency very low. As a solar pumped semiconductor lasers could absorb all photons with energy greater than the bandgap. Thus, solar pumped semiconductor lasers could have considerably higher efficiencies than other solar pumped lasers. Besides, solar pumped semiconductor lasers has smaller volume chip, simpler structure and better heat dissipation, it can be mounted on a small satellite platform, can compose satellite array, which can greatly improve the output power of the system, and have flexible character. This paper summarizes the research progress of space-based solar pumped semiconductor lasers, analyses of the key technologies based on several application areas, including the processing of semiconductor chip, the design of small and efficient solar condenser, and the cooling system of lasers, etc. We conclude that the solar pumped vertical cavity surface-emitting semiconductor lasers will have a wide application prospects in the space.

Solar Energy and Other Appropriate Technologies for Small Potable Water Systems in Puerto Rico

EPA Science Inventory

This Region 2 research demonstration project presentation studied the efficacy of sustainable solar-powered water delivery and monitoring systems to reduce the economic burden of operating and maintaining Non-PRASA drinking water systems and to reduce the impact of climate change...

An experimental study of potential residential and commercial applications of small-scale hybrid power systems

NASA Astrophysics Data System (ADS)

Acosta, Michael Anthony

The research presented in this thesis provides an understanding of small-scale hybrid power systems. Experiments were conducted to identify potential applications of renewable energy in residential and commercial applications in the Rio Grande Valley of Texas. Solar and wind energy converted into electric energy was stored in batteries and inverted to power common household and commercial appliances. Several small to medium size hybrid power systems were setup and utilized to conduct numerous tests to study renewable energy prospects and feasibility for various applications. The experimental results obtained indicate that carefully constructed solar power systems can provide people living in isolated communities with sufficient energy to consistently meet their basic power needs.

Terahertz photometers to observe solar flares from space (SOLAR-T project)

NASA Astrophysics Data System (ADS)

Kaufmann, Pierre; Raulin, Jean-Pierre

The space experiment SOLAR-T designed to observe solar flares at THz frequencies was completed. We present the concept, fabrication and performance of a double THz photometers system. An innovative optical setup allows observations of the full solar disk and the detection of small burst transients at the same time. It is the first detecting system conceived to observe solar flare THz emissions on board of stratospheric balloons. The system has been integrated to data acquisition and telemetry modules for this application. SOLAR-T uses two Golay cell detectors preceded by low-pass filters made of rough surface primary mirrors and membranes, 3 and 7 THz band-pass filters, and choppers. Its photometers can detect small solar bursts (tens of solar flux units) with sub second time resolution. One artificial Sun setup was developed to simulate actual observations. Tests comprised the whole system performance, on ambient and low pressure and temperature conditions. It is intended to provide data on the still unrevealed spectral shape of the mysterious THz solar flares emissions. The experiment is planned to be on board of two long-duration stratospheric balloon flights over Antarctica and Russia in 2014-2016. The SOLAR-T development, fabrication and tests has been accomplished by engineering and research teams from Mackenzie, Unicamp and Bernard Lyot Solar Observatory; Propertech Ltda.; Neuron Ltda.; and Samsung, Brazil; Tydex LCC, Russia; CONICET, Argentina; the stratospheric balloon missions will be carried in cooperation with teams from University of California, Berkeley, USA (flight over Antarctica), and Lebedev Physical Institute, Moscow, Russia (flight over Russia).

Energy Primer: Solar, Water, Wind, and Biofuels.

ERIC Educational Resources Information Center

Portola Inst., Inc., Menlo Park, CA.

This is a comprehensive, fairly technical book about renewable forms of energy--solar, water, wind, and biofuels. The biofuels section covers biomass energy, agriculture, aquaculture, alcohol, methane, and wood. The focus is on small-scale systems which can be applied to the needs of the individual, small group, or community. More than one-fourth…

Small- Geo Solar Array: New Generation Of Solar Arrays For Commercial Telecom Satellites For Power Ranges Between 2,5 KW And 7,5 KW

NASA Astrophysics Data System (ADS)

Paarmann, Carola; Muller, Jens; Mende, Thomas; Borner, Carsten; Mascher, Rolf

2011-10-01

In the frame of the ESA supported Artes 11 program a new generation of GEO telecommunication satellites is under development. This platform will cover the power range from 2 to 5 kW. ASTRIUM GmbH is contracted to develop and design the Solar Array for this platform. Furthermore the manufacturing and the qualification of a PFM wing for the first flight model is foreseen. The satellite platform, called Small-GEO, is developed under the responsibility of OHB System. This first Small-GEO satellite is designated to be delivered to HISPASAT for operation. The concept of ASTRIUM GmbH is to use all the experiences from the very successful EUROSTAR 2000+, EUROSTAR-3000 and the ALPHABUS platform and to adapt the technologies to the Small- GEO Solar Array. With the benefit of the huge in-orbit heritage of these programs, the remaining risks for the Small-GEO Solar Array can be minimized. The development of the Small-GEO Solar Array extends the ASTRIUM GmbH product portfolio by covering now the complete power range between 2 kW and 31 kW. This paper provides an overview of the different configurations, their main design features and parameters.

Advancements of the Lightweight Integrated Solar Array and Transceiver (LISA-T) Small Spacecraft System

NASA Technical Reports Server (NTRS)

Lockett, Tiffany Russell; Martinez, Armando; Boyd, Darren; SanSouice, Michael; Farmer, Brandon; Schneider, Todd; Laue, Greg; Fabisinski, Leo; Johnson, Les; Carr, John A.

2015-01-01

This paper describes recent advancements of the Lightweight Integrated Solar Array and Transceiver (LISA-T) currently being developed at NASA's Marshall Space Flight Center. The LISA-T array comprises a launch stowed, orbit deployed structure on which thin-film photovoltaic (PV) and antenna devices are embedded. The system provides significant electrical power generation at low weights, high stowage efficiency, and without the need for solar tracking. Leveraging high-volume terrestrial-market PVs also gives the potential for lower array costs. LISA-T is addressing the power starvation epidemic currently seen by many small-scale satellites while also enabling the application of deployable antenna arrays. Herein, an overview of the system and its applications are presented alongside sub-system development progress and environmental testing plans.

Advancements of the Lightweight Integrated Solar Array and Transceiver (LISA-T) Small Spacecraft System

NASA Technical Reports Server (NTRS)

Russell, Tiffany; Martinez, Armando; Boyd, Darren; SanSoucie, Michael; Farmer, Brandon; Schneider, Todd; Fabisinski, Leo; Johnson, Les; Carr, John A.

2015-01-01

This paper describes recent advancements of the Lightweight Integrated Solar Array and Transceiver (LISA-T) currently being developed at NASA's Marshall Space Flight Center. The LISA-T array comprises a launch stowed, orbit deployed structure on which thin-film photovoltaic (PV) and antenna devices are embedded. The system provides significant electrical power generation at low weights, high stowage efficiency, and without the need for solar tracking. Leveraging high-volume terrestrial-market PVs also gives the potential for lower array costs. LISA-T is addressing the power starvation epidemic currently seen by many small-scale satellites while also enabling the application of deployable antenna arrays. Herein, an overview of the system and its applications are presented alongside sub-system development progress and environmental testing plans/initial results.

The dish-Rankine SCSTPE program (Engineering Experiment no. 1). [systems engineering and economic analysis for a small community solar thermal electric system

NASA Technical Reports Server (NTRS)

Pons, R. L.; Grigsby, C. E.

1980-01-01

Activities planned for phase 2 Of the Small Community Solar Thermal Power Experiment (PFDR) program are summarized with emphasis on a dish-Rankine point focusing distributed receiver solar thermal electric system. Major design efforts include: (1) development of an advanced concept indirect-heated receiver;(2) development of hardware and software for a totally unmanned power plant control system; (3) implementation of a hybrid digital simulator which will validate plant operation prior to field testing; and (4) the acquisition of an efficient organic Rankine cycle power conversion unit. Preliminary performance analyses indicate that a mass-produced dish-Rankine PFDR system is potentially capable of producing electricity at a levelized busbar energy cost of 60 to 70 mills per KWh and with a capital cost of about $1300 per KW.

Charging system using solar panels and a highly resonant wireless power transfer model for small UAS applications

NASA Astrophysics Data System (ADS)

Hallman, Sydney N.; Huck, Robert C.; Sluss, James J.

2016-05-01

The use of a wireless charging system for small, unmanned aircraft system applications is useful for both military and commercial consumers. An efficient way to keep the aircraft's batteries charged without interrupting flight would be highly marketable. While the general concepts behind highly resonant wireless power transfer are discussed in a few publications, the details behind the system designs are not available even in academic journals, especially in relation to avionics. Combining a highly resonant charging system with a solar panel charging system can produce enough power to extend the flight time of a small, unmanned aircraft system without interruption. This paper provides an overview of a few of the wireless-charging technologies currently available and outlines a preliminary design for an aircraft-mounted battery charging system.

Appropriate technology for rural India - solar decontamination of water for emergency settings and small communities.

PubMed

Kang, Gagandeep; Roy, Sheela; Balraj, Vinohar

2006-09-01

A commercial solar water heating system was evaluated for its effectiveness in decontaminating drinking water with a view to use in emergency situations. A total of 18 seeding experiments carried out over 6 months with 10(5) to 10(7)Escherichia coli/ml showed that the solar heater produced 125 l of bacteriologically safe water in 4 h when the ambient temperature was above 30 degrees C, with a holding time of at least 2 h. The solar water heating system is inexpensive, easy to transport and set up and could provide safer drinking water for 50 people a day. It would be effective in the decrease and prevention of waterborne disease in emergency situations, and is appropriate for use in small communities.

Observations of Planet Crossing Asteroids

NASA Technical Reports Server (NTRS)

Tholen, David J.

1999-01-01

This grant funds the investigation of the Solar System's planet crossing asteroid population, principally the near Earth and trans-Neptunian objects, but also the Centaurs. Investigations include colorimetry at both visible and near infrared wavelengths, light curve photometry, astrometry, and a pilot project to find near Earth objects with small aphelion distances, which requires observations at small solar elongations.

78 FR 19183 - Notice of Funding Availability for the Rural Energy for America Program

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-29

... project contains a wind and solar photovoltaic components. The wind system will cost $30,000 (75 percent... facilities. For example, a rural small business owner owns five retail stores and wishes to install solar... solar panels on the five stores. However, if this same owner wishes to install solar panels on three of...

Connective power: Solar electrification and social change in Kenya

NASA Astrophysics Data System (ADS)

Jacobson, Arne Edward

Household solar photovoltaic systems have emerged as a key alternative to grid-based rural electrification in many developing countries. This may seem a victory for appropriate technology advocates, but my research indicates that the social significance of solar electrification in Kenya, which is among the largest developing country solar markets per capita, is far removed from the classic "small is beautiful" neo-populist vision of building small-scale alternatives to global capitalism. Instead, solar electrification is more closely connected to neo-liberal goals of market-based service provision and economic integration. In this study I combine quantitative and qualitative methods, including surveys, intra-household energy allocation studies, and historical analysis, to analyze the social significance of solar electrification in Kenya. I find that "connective" applications, including television, radio, and cellphones, are centrally important. Television is especially notable; the expansion of TV broadcasting to rural areas was a key condition for solar market development. Solar electricity is also used for lighting. In Kenya, income and work related uses of solar lighting are modest, while education uses are more significant. However, in many households, especially those with small systems, intra-household dynamics constrain key social uses (e.g. children's studying), as the energy is allocated to other uses. Social use patterns combine with access dynamics in Kenya's unsubsidized market to shape the social significance of solar electrification. Solar ownership is dominated by the rural upper and middle classes. Thus, productivity and education uses make small contributions to differentiation and middle class formation. Additionally, solar electrification's role in supporting rural television and radio use improves business advertisers' ability to expand consumer goods markets. These findings link solar electrification to important processes of rural development and social change. Mainstream policy makers have sought to expand the market through credit-based sales. However, my analysis indicates that, without subsidies, credit-based sales are unlikely to deepen access beyond levels established in the existing cash market. Thus, while solar electrification may potentially contribute to sustainable development, concerns about equity and other social issues indicate a need for careful attention to the implications of policy choices and processes that influence the social use possibilities of the technology.

Phase 1 of the First Small Power System Experiment (engineering Experiment No. 1). Volume 1: Executive Summary. [development and testing of a solar thermal power plant

NASA Technical Reports Server (NTRS)

Holl, R. J.

1979-01-01

The development of a modular solar thermal power system for application in the 1 to 10 MWe range is presented. The system is used in remote utility applications, small communities, rural areas, and for industrial uses. Investigations are performed on the energy storage requirements and type of energy storage, concentrator design and field optimization, energy transport, and power conversion subsystems. The system utilizes a Rankine cycle, an axial flow steam turbine for power conversion, and heat transfer sodium for collector fluid.

Multiscale Molecular Simulation of Solution Processing of SMDPPEH: PCBM Small-Molecule Organic Solar Cells.

PubMed

Lee, Cheng-Kuang; Pao, Chun-Wei

2016-08-17

Solution-processed small-molecule organic solar cells are a promising renewable energy source because of their low production cost, mechanical flexibility, and light weight relative to their pure inorganic counterparts. In this work, we developed a coarse-grained (CG) Gay-Berne ellipsoid molecular simulation model based on atomistic trajectories from all-atom molecular dynamics simulations of smaller system sizes to systematically study the nanomorphology of the SMDPPEH/PCBM/solvent ternary blend during solution processing, including the blade-coating process by applying external shear to the solution. With the significantly reduced overall system degrees of freedom and computational acceleration from GPU, we were able to go well beyond the limitation of conventional all-atom molecular simulations with a system size on the order of hundreds of nanometers with mesoscale molecular detail. Our simulations indicate that, similar to polymer solar cells, the optimal blending ratio in small-molecule organic solar cells must provide the highest specific interfacial area for efficient exciton dissociation, while retaining balanced hole/electron transport pathway percolation. We also reveal that blade-coating processes have a significant impact on nanomorphology. For given donor/acceptor blending ratios, applying an external shear force can effectively promote donor/acceptor phase segregation and stacking in the SMDPPEH domains. The present study demonstrated the capability of an ellipsoid-based coarse-grained model for studying the nanomorphology evolution of small-molecule organic solar cells during solution processing/blade-coating and provided links between fabrication protocols and device nanomorphologies.

Techno-economic projections for advanced small solar thermal electric power plants to years 1990-2000

NASA Technical Reports Server (NTRS)

Fujita, T.; Manvi, R.; Roschke, E. J.; El-Gabalawi, N.; Herrera, G.; Kuo, T. J.; Chen, K. H.

1979-01-01

Advanced technologies applicable to solar thermal electric power systems in the 1990-200 time-frame are delineated for power applications that fulfill a wide spectrum of small power needs with primary emphasis on power ratings less than 10MWe. Projections of power system characteristics (energy and capital costs as a function of capacity factor) are made based on development of identified promising technologies and are used as the basis for comparing technology development options and combinations of these options to determine developmental directions offering potential for significant improvements. Stirling engines, Brayton/Rankine combined cycles and storage/transport concepts encompassing liquid metals, and reversible-reaction chemical systems are considered for two-axis tracking systems such as the central receiver or power tower concept and distributed parabolic dish receivers which can provide efficient low-cost solar energy collection while achieving high temperatures for efficient energy conversion. Pursuit of advanced technology across a broad front can result in post-1985 solar thermal systems having the potential of approaching the goal of competitiveness with conventional power systems.

Trojan Tour and Rendezvous (TTR): A New Frontiers Mission to Explore the Origin and Evolution of the Early Solar System

NASA Astrophysics Data System (ADS)

Bell, J. F., III; Olkin, C.; Castillo, J. C.

2015-12-01

The orbital properties, compositions, and physical properties of the diverse populations of small outer solar system bodies provide a forensic map of how our solar system formed and evolved. Perhaps the most potentially diagnostic, but least explored, of those populations are the Jupiter Trojan asteroids, which orbit at ~5 AU in the L4 and L5 Lagrange points of Jupiter. More than 6200 Jupiter Trojans are presently known, but these are predicted to be only a small fraction of the 500,000 to 1 million Trojans >1 km in size. The Trojans are hypothesized to be either former Kuiper Belt Objects (KBOs) that were scattered into the inner solar system by early giant planet migration and then trapped in the 1:1 Jupiter mean motion resonance, or bodies formed near 5 AU in a much more quiescent early solar system, and then trapped at L4 and L5. The 2011 Planetary Science Decadal Survey identified important questions about the origin and evolution of the solar system that can be addressed by studying of the Trojan asteroids, including: (a) How did the giant planets and their satellite systems accrete, and is there evidence that they migrated to new orbital positions? (b) What is the relationship between large and small KBOs? Is the small population derived by impact disruption of the large one? (c) What kinds of surface evolution, radiation chemistry, and surface-atmosphere interactions occur on distant icy primitive bodies? And (d) What are the sources of asteroid groups (Trojans and Centaurs) that remain to be explored by spacecraft? The Trojan Tour and Rendezvous (TTR) is a New Frontiers-class mission designed to answer these questions, and to test hypotheses for early giant planet migration and solar system evolution. Via close flybys of a large number of these objects,, and orbital characterization of at least one large Trojan, TTR will enable the first-time exploration of this population. Our primary mission goals are to characterize the overall surface geology, geochemistry and mineralogy of these worlds; to characterize their internal structure and dynamical properties; to investigate the nature, sources and history of activity on these bodies; and to explore the diversity of the broader Trojan asteroid population.

Preferences and concerns of potential users in the selection of solar thermal systems for industrial and small utility applications

NASA Astrophysics Data System (ADS)

Gresham, J. B.; Kriz, T. A.

1981-03-01

To achieve widespread application in the industrial and utility sectors, solar systems must be economically competitive. Economic viability is, in turn, determined by a number of supporting criteria, ranging from system reliability to dispatch characteristics to how the system supports the main product line. In addition, solar systems possess some inherent attributes that may render some of the traditional supporting criteria inappropriate or require their redefinition. Those criteria and their relation to the solar investments are discussed in three steps. First, the main concerns and preferences of the potential users, as identified in recent SERI studies, are identified. Second, the equitability of the resulting decision criteria for solar investments are examined. Finally, the implications of these criteria for solar energy's penetration into these markets are discussed.

Lightweight Inflatable Solar Array: Providing a Flexible, Efficient Solution to Space Power Systems for Small Spacecraft

NASA Technical Reports Server (NTRS)

Johnson, Les; Fabisinski, Leo; Justice, Stefanie

2014-01-01

Affordable and convenient access to electrical power is critical to consumers, spacecraft, military and other applications alike. In the aerospace industry, an increased emphasis on small satellite flights and a move toward CubeSat and NanoSat technologies, the need for systems that could package into a small stowage volume while still being able to power robust space missions has become more critical. As a result, the Marshall Space Flight Center's Advanced Concepts Office identified a need for more efficient, affordable, and smaller space power systems to trade in performing design and feasibility studies. The Lightweight Inflatable Solar Array (LISA), a concept designed, prototyped, and tested at the NASA Marshall Space Flight Center (MSFC) in Huntsville, Alabama provides an affordable, lightweight, scalable, and easily manufactured approach for power generation in space or on Earth. This flexible technology has many wide-ranging applications from serving small satellites to soldiers in the field. By using very thin, ultraflexible solar arrays adhered to an inflatable structure, a large area (and thus large amount of power) can be folded and packaged into a relatively small volume (shown in artist rendering in Figure 1 below). The proposed presentation will provide an overview of the progress to date on the LISA project as well as a look at its potential, with continued development, to revolutionize small spacecraft and portable terrestrial power systems.

Title Requested

NASA Astrophysics Data System (ADS)

Ruzmaikina, T. V.

2000-12-01

Precise measurements of D/H in Halley and Hyakutake reveal larger excess of D than in Uranus and Neptune. This might imply that at least a fraction of Oort cloud comets have been accumulated in a cooler environment beyond the planetary system. This paper suggests that the scattering of planetesimals from the periphery of the protoplanetary disk by a passing star might have included them in the populating of the Oort cloud. The probability of the necessary close encounter is very small in the present Galactic environment of the solar system. However it might be relatively high if the solar system was formed in a denser environment, like the Rho Ophiuchus star-forming region or a small and dense cloud core which fragmented during the collapse to form a small group of stars. Outcomes of a passage of a star with mass 1 to 0.3 solar masses were studied numerically by Everhart method. Disk penetrating or disk grazing encounters revealed that planetesimals closest to the stellar trajectory can be ejected from the solar system or sent on highly eccentric bound orbits. Some planetesimals acquire orbits with perihelion distances larger than planet orbits, i.e., become immediate members of the Oort cloud. For others, external pertubations cause stochastic growth of perihelion distances and decoupling from the planetary system, transferring them into the Oort cloud. These Oort cloud bodies could be accumulated well beyond the planetary system, and preserve higher D/H, CO ice, etc.

Heat engine development for solar thermal power systems

NASA Astrophysics Data System (ADS)

Pham, H. Q.; Jaffe, L. D.

The parabolic dish solar collector systems for converting sunlight to electrical power through a heat engine will, require a small heat engine of high performance long lifetime to be competitive with conventional power systems. The most promising engine candidates are Stirling, high temperature Brayton, and combined cycle. Engines available in the current market today do not meet these requirements. The development of Stirling and high temperature Brayton for automotive applications was studied which utilizes much of the technology developed in this automotive program for solar power engines. The technical status of the engine candidates is reviewed and the components that may additional development to meet solar thermal system requirements are identified.

Proof-of-Concept Testing of the Passive Cooling System (T-CLIP™) for Solar Thermal Applications at an Elevated Temperature

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

Kim, Seung Jun; Quintana, Donald L.; Vigil, Gabrielle M.

2015-11-30

The Applied Engineering and Technology-1 group (AET-1) at Los Alamos National Laboratory (LANL) conducted the proof-of-concept tests of SolarSPOT LLC’s solar thermal Temperature- Clipper, or T-CLIP™ under controlled thermal conditions using a thermal conditioning unit (TCU) and a custom made environmental chamber. The passive T-CLIP™ is a plumbing apparatus that attaches to a solar thermal collector to limit working fluid temperature and to prevent overheating, since overheating may lead to various accident scenarios. The goal of the current research was to evaluate the ability of the T-CLIP™ to control the working fluid temperature by using its passive cooling mechanism (i.e.more » thermosiphon, or natural circulation) in a small-scale solar thermal system. The assembled environmental chamber that is thermally controlled with the TCU allows one to simulate the various possible weather conditions, which the solar system will encounter. The performance of the T-CLIP™ was tested at two different target temperatures: 1) room temperature (70 °F) and 2) an elevated temperature (130 °F). The current test campaign demonstrated that the T-CLIP™ was able to prevent overheating by thermosiphon induced cooling in a small-scale solar thermal system. This is an important safety feature in situations where the pump is turned off due to malfunction or power outages.« less

Geostationary Space Launch Vehicles and the U.S. Dilemma

DTIC Science & Technology

1994-06-17

solar panels for power generation and no attitude control system for orbit stabilization. The communications circuits were underpowered because the... solar panels were small compared to the ones used on GEO satellites today. Although the lack of attitude control systems greatly reduced the weight of...to ten year useful life has been realized using good fuel management techniques. The size of the solar panels on GEO satellites have been the

Advanced subsystems development

NASA Technical Reports Server (NTRS)

Livingston, F. R.

1978-01-01

The concept design for a small (less than 10 MWe) solar thermal electric generating plant was completed using projected 1985 technology. The systems requirements were defined and specified. The components, including an engineering prototype for one 15 kWe module of the generating plant, were conceptually designed. Significant features of the small solar thermal power plant were identified as the following: (1) 15 kWe Stirling-cycle engine/alternator with constant power output; (2) 10 meter point-focusing paraboloidal concentrator with cantilevered cellular glass reflecting panels; (3) primary heat pipe with 800 C output solar cavity receiver; (4) secondary heat pipe with molten salt thermal energy storage unit; (5) electric energy transport system; and (6) advanced battery energy storage capability.

Villacidro solar demo plant: Integration of small-scale CSP and biogas power plants in an industrial microgrid

NASA Astrophysics Data System (ADS)

Camerada, M.; Cau, G.; Cocco, D.; Damiano, A.; Demontis, V.; Melis, T.; Musio, M.

2016-05-01

The integration of small scale concentrating solar power (CSP) in an industrial district, in order to develop a microgrid fully supplied by renewable energy sources, is presented in this paper. The plant aims to assess in real operating conditions, the performance, the effectiveness and the reliability of small-scale concentrating solar power technologies in the field of distributed generation. In particular, the potentiality of small scale CSP with thermal storage to supply dispatchable electricity to an industrial microgrid will be investigated. The microgrid will be realized in the municipal waste treatment plant of the Industrial Consortium of Villacidro, in southern Sardinia (Italy), which already includes a biogas power plant. In order to achieve the microgrid instantaneous energy balance, the analysis of the time evolution of the waste treatment plant demand and of the generation in the existing power systems has been carried out. This has allowed the design of a suitable CSP plant with thermal storage and an electrochemical storage system for supporting the proposed microgrid. At the aim of obtaining the expected energy autonomy, a specific Energy Management Strategy, which takes into account the different dynamic performances and characteristics of the demand and the generation, has been designed. In this paper, the configuration of the proposed small scale concentrating solar power (CSP) and of its thermal energy storage, based on thermocline principle, is initially described. Finally, a simulation study of the entire power system, imposing scheduled profiles based on weather forecasts, is presented.

Developing wind and/or solar powered crop irrigation systems for the Great Plains

USDA-ARS?s Scientific Manuscript database

Some small scale, off-grid irrigation systems (less than 2.5 ha) that are powered by wind or solar energy are cost effective, but this paper discusses ways to achieve an economical renewable energy powered center pivot irrigation system for crops in the Great Plains. It was found that partitioning t...

Revitalize Electrical Program with Renewable Energy Focus

ERIC Educational Resources Information Center

Karns, Robert J.

2012-01-01

Starting a renewable energy technology (RET) program can be as simple as shifting the teaching and learning focus of a traditional electricity program toward energy production and energy control systems. Redirecting curriculum content and delivery to address photovoltaic solar (PV solar) technology and small wind generation systems is a natural…

Solar parabolic dish technology evaluation report

NASA Technical Reports Server (NTRS)

Lucas, J. W.

1984-01-01

The activities of the JPL Solar Thermal Power Systems Parabolic Dish Project for FY 1983 are summarized. Included are discussions on designs of module development including concentrator, receiver, and power conversion subsystems together with a separate discussion of field tests, Small Community Experiment system development, and tests at the Parabolic Dish Test Site.

A novel photovoltaic power system which uses a large area concentrator mirror

NASA Technical Reports Server (NTRS)

Arrison, Anne; Fatemi, Navid

1987-01-01

A preliminary analysis has been made of a novel photovoltaic power system concept. The system is composed of a small area, dense photovoltaic array, a large area solar concentrator, and a battery system for energy storage. The feasibility of such a system is assessed for space power applications. The orbital efficiency, specific power, mass, and area of the system are calculated under various conditions and compared with those for the organic Rankine cycle solar dynamic system proposed for Space Station. Near term and advanced large area concentrator photovoltaic systems not only compare favorably to solar dynamic systems in terms of performance but offer other benefits as well.

German-Korean cooperation for erection and test of industrialized solar technologies

NASA Astrophysics Data System (ADS)

Pfeiffer, H.

1986-01-01

A combined small solar-wind power station and a solar-thermal experimental plant were built. The plants are designed to demonstrate the effective exploitation of solar energy and wind energy and enhanced availability achievable through combination of these two energy sources. A 14 kW wind energy converter and a 2.5 kW solar-cell generator were operated in parallel. The biaxial tracking system used on the solar generator leads to increased and constant generation of electricity throughout the day. A consumer control system switches the energy generators and the consumers in autonomous mode according to changing supply and demand. The solar powered air conditioning unit operates with an absorption type refrigerating unit, high-output flat collectors and an automatic control system. All design values are achieved on start-up of the plant.

A small electron donor in cobalt complex electrolyte significantly improves efficiency in dye-sensitized solar cells

PubMed Central

Hao, Yan; Yang, Wenxing; Zhang, Lei; Jiang, Roger; Mijangos, Edgar; Saygili, Yasemin; Hammarström, Leif; Hagfeldt, Anders; Boschloo, Gerrit

2016-01-01

Photoelectrochemical approach to solar energy conversion demands a kinetic optimization of various light-induced electron transfer processes. Of great importance are the redox mediator systems accomplishing the electron transfer processes at the semiconductor/electrolyte interface, therefore affecting profoundly the performance of various photoelectrochemical cells. Here, we develop a strategy—by addition of a small organic electron donor, tris(4-methoxyphenyl)amine, into state-of-art cobalt tris(bipyridine) redox electrolyte—to significantly improve the efficiency of dye-sensitized solar cells. The developed solar cells exhibit efficiency of 11.7 and 10.5%, at 0.46 and one-sun illumination, respectively, corresponding to a 26% efficiency improvement compared with the standard electrolyte. Preliminary stability tests showed the solar cell retained 90% of its initial efficiency after 250 h continuous one-sun light soaking. Detailed mechanistic studies reveal the crucial role of the electron transfer cascade processes within the new redox system. PMID:28000672

Solar/hydrogen systems assessment. Volume 1: Solar/hydrogen systems for the 1985 - 2000 time frame

NASA Technical Reports Server (NTRS)

Foster, R. W.; Tison, R. R.; Escher, W. J. D.; Hanson, J. A.

1980-01-01

Opportunities for commercialization of systems capable of producing hydrogen from solar energy were studied. The hydrogen product costs that might be achieved by the four selected candidate systems was compared with the pricing structure and practices of the commodity gas market. Subsequently, product cost and market price match was noted to exist in the small user sector of the hydrogen marketplace. Barriers to and historical time lags in, commercialization of new technologies are reviewed. Recommendations for development and demonstration programs designed to accelerate the commercialization of the candidate systems are presented.

Solar/hydrogen systems assessment. Volume 1: Solar/hydrogen systems for the 1985 - 2000 time frame

NASA Astrophysics Data System (ADS)

Foster, R. W.; Tison, R. R.; Escher, W. J. D.; Hanson, J. A.

1980-06-01

Opportunities for commercialization of systems capable of producing hydrogen from solar energy were studied. The hydrogen product costs that might be achieved by the four selected candidate systems was compared with the pricing structure and practices of the commodity gas market. Subsequently, product cost and market price match was noted to exist in the small user sector of the hydrogen marketplace. Barriers to and historical time lags in, commercialization of new technologies are reviewed. Recommendations for development and demonstration programs designed to accelerate the commercialization of the candidate systems are presented.

The future of Stardust science

NASA Astrophysics Data System (ADS)

Westphal, A. J.; Bridges, J. C.; Brownlee, D. E.; Butterworth, A. L.; de Gregorio, B. T.; Dominguez, G.; Flynn, G. J.; Gainsforth, Z.; Ishii, H. A.; Joswiak, D.; Nittler, L. R.; Ogliore, R. C.; Palma, R.; Pepin, R. O.; Stephan, T.; Zolensky, M. E.

2017-09-01

Recent observations indicate that >99% of the small bodies in the solar system reside in its outer reaches—in the Kuiper Belt and Oort Cloud. Kuiper Belt bodies are probably the best-preserved representatives of the icy planetesimals that dominated the bulk of the solid mass in the early solar system. They likely contain preserved materials inherited from the protosolar cloud, held in cryogenic storage since the formation of the solar system. Despite their importance, they are relatively underrepresented in our extraterrestrial sample collections by many orders of magnitude ( 1013 by mass) as compared with the asteroids, represented by meteorites, which are composed of materials that have generally been strongly altered by thermal and aqueous processes. We have only begun to scratch the surface in understanding Kuiper Belt objects, but it is already clear that the very limited samples of them that we have in our laboratories hold the promise of dramatically expanding our understanding of the formation of the solar system. Stardust returned the first samples from a known small solar system body, the Jupiter-family comet 81P/Wild 2, and, in a separate collector, the first solid samples from the local interstellar medium. The first decade of Stardust research resulted in more than 142 peer-reviewed publications, including 15 papers in Science. Analyses of these amazing samples continue to yield unexpected discoveries and to raise new questions about the history of the early solar system. We identify nine high-priority scientific objectives for future Stardust analyses that address important unsolved problems in planetary science.

Phase 1 of the First Small Power System Experiment (engineering Experiment No. 1). Volume 2: System Concept Selection. [development and testing of a solar thermal power plant

NASA Technical Reports Server (NTRS)

Holl, R. J.

1979-01-01

The development of a modular solar thermal power system for application in the 1 to 10 MWe range is presented. The system is used in remote utility applications, small communities, rural areas, and for industrial uses. Systems design and systems optimization studies are conducted which consider plant size, annual capacity factors, and startup time as variables. Investigations are performed on the energy storage requirements and type of energy storage, concentrator design and field optimization, energy transport, and power conversion subsystems. The system utilizes a Rankine cycle, an axial flow steam turbine for power conversion, and heat transfer sodium for collector fluid.

77 FR 26507 - Application(s) for Duty-Free Entry of Scientific Instruments

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-04

...: FEI Company, Czech Republic. Intended Use: The instrument will be used for research on primitive solar system materials extracted from meteorites as well as on samples from NASA sample return missions, such... chemical origin of the solar system and the processes by which its small bodies evolved. Justification for...

Exploring the Solar System? Let the Math Teachers Help!

ERIC Educational Resources Information Center

Charles, Karen; Canales, J. D.; Smith, Angela; Zimmerman, Natalie

2012-01-01

Scale measurement and ratio and proportion are topics that fall clearly in the middle-grades mathematics curriculum in Texas. So does the solar system. In their experience, the authors have found that students have trouble manipulating, much less comprehending, very large numbers and very small numbers. These concepts can be brought into students'…

Small solar thermal electric power plants with early commercial potential

NASA Technical Reports Server (NTRS)

Jones, H. E.; Bisantz, D. J.; Clayton, R. N.; Heiges, H. H.; Ku, A. C.

1979-01-01

Cost-effective small solar thermal electric power plants (1- to 10-MW nominal size) offer an attractive way of helping the world meet its future energy needs. The paper describes the characteristics of a conceptual near-term plant (about 1 MW) and a potential 1990 commercial version. The basic system concept is one in which steam is generated using two-axis tracking, parabolic dish, and point-focusing collectors. The steam is transported through low-loss piping to a central steam turbine generator unit where it is converted to electricity. The plants have no energy storage and their output power level varies with the solar insolation level. This system concept, which is firmly based on state-of-the-art technology, is projected to offer one of the fastest paths for U.S. commercialization of solar thermal electric power plants through moderate technology advances and mass production.

Designing a Small-Sized Engineering Model of Solar EUV Telescopr for a Korean Satellite

NASA Astrophysics Data System (ADS)

Han, Jung-Hoon; Jang, Min-Hwan; Kim, Sang-Joon

2001-11-01

For the research of solar EUV (extreme ultraviolet) radiation, we have designed a small-sized engineering model of solar EUV telescope, which is suitable for a Korean satellite. The EUV solar telescope was designed to observe the sun at 584.3Å (He¥°) and 629.7Å (O¥´). The optical system is an f/8 Ritchey-Chrètien, and the effective diameter and focal length are 80§® and 640§®, respectively. The He¥°and O¥´ filters are loaded in a filter wheel. In the detection part, the MCP (MicroChannel Plate) type is Z-stack, and the channel-to-diameter ratio is 40:1. MCP and CCD are connected by fiber optic taper. A commercial optical design software is used for the analysis of the optical system design.

Small solar system bodies as granular systems

NASA Astrophysics Data System (ADS)

Hestroffer, Daniel; Campo Bagatín, Adriano; Losert, Wolfgang; Opsomer, Eric; Sánchez, Paul; Scheeres, Daniel J.; Staron, Lydie; Taberlet, Nicolas; Yano, Hajime; Eggl, Siegfried; Lecomte, Charles-Edouard; Murdoch, Naomi; Radjai, Fahrang; Richardson, Derek C.; Salazar, Marcos; Schwartz, Stephen R.; Tanga, Paolo

2017-06-01

Asteroids and other Small Solar System Bodies (SSSBs) are currently of great scientific and even industrial interest. Asteroids exist as the permanent record of the formation of the Solar System and therefore hold many clues to its understanding as a whole, as well as insights into the formation of planetary bodies. Additionally, SSSBs are being investigated in the context of impact risks for the Earth, space situational awareness and their possible industrial exploitation (asteroid mining). In all these aspects, the knowledge of the geophysical characteristics of SSSB surface and internal structure are of great importance. Given their size, constitution, and the evidence that many SSSBs are not simple monoliths, these bodies should be studied and modelled as self-gravitating granular systems in general, or as granular systems in micro-gravity environments in particular contexts. As such, the study of the geophysical characteristics of SSSBs is a multi-disciplinary effort that lies at the crossroads between Granular Mechanics, Celestial Mechanics, Soil Mechanics, Aerospace Engineering and Computer Sciences.

Navigation for Rendezvous and Orbit Missions to Small Solar-System Bodies

NASA Technical Reports Server (NTRS)

Helfrich, C. E.; Scheeres, D. J.; Williams, B. G.; Bollman, W. E.; Davis, R. P.; Synnott, S. P.; Yeomans, D. K.

1994-01-01

All previous spacecraft encounters with small solar-system bodies, such as asteroids and comets, have been flybys (e.g. Galileo's flybys of the asteroids Gaspra and Ida). Several future projects plan to build on the flyby experience and progress to the next level with rendezvous and orbit missions to small bodies. This presents several new issues and challenges for navigation which have never been considered before. This paper addresses these challenges by characterizing the different phases of a small body rendezvous and by describing the navigation requirements and goals of each phase. Prior to the encounter with the small body, improvements to its ephemeris and initial estimates of its physical parameters, e.g. size, shape, mass, rotation rate, rotation pole, and possibly outgassing, are made as accurately as ground-based measurements allow. This characterization can take place over years...

Lightweight Solar Power for Small Satellites

NASA Technical Reports Server (NTRS)

Nabors, Sammy A.

2015-01-01

The innovation targets small satellites or CubeSats for which conventional deployable arrays are not feasible due to their size, weight and complexity. This novel solar cell array includes a thin and flexible photovoltaic cell applied to an inflatable structure to create a high surface area array for collecting solar energy in a lightweight, simple and deployable structure. The inflatable array, with its high functional surface area, eliminates the need and the mechanisms required to point the system toward the sun. The power density achievable in these small arrays is similar to that of conventional high-power deployable/pointable arrays used on large satellites or space vehicles. Although inflatable solar arrays have been previously considered by others, the arrays involved the use of traditional rigid solar cells. Researchers are currently working with thin film photovoltaics from various suppliers so that the NASA innovation is not limited to any particular solar cell technology. NASA has built prototypes and tested functionality before and after inflation. As shown in the current-voltage currents below, deployment does not damage the cell performance.

Filling in the Gaps: Xenoliths in Meteorites are Samples of "Missing" Asteroid Lithologies

NASA Technical Reports Server (NTRS)

Zolensky, Mike

2016-01-01

We know that the stones that fall to earth as meteorites are not representative of the full diversity of small solar system bodies, because of the peculiarities of the dynamical processes that send material into Earth-crossing paths [1] which result in severe selection biases. Thus, the bulk of the meteorites that fall are insufficient to understand the full range of early solar system processes. However, the situation is different for pebble- and smaller-sized objects that stream past the giant planets and asteroid belts into the inner solar system in a representative manner. Thus, micrometeorites and interplanetary dust particles have been exploited to permit study of objects that do not provide meteorites to earth. However, there is another population of materials that sample a larger range of small solar system bodies, but which have received little attention - pebble-sized foreign clasts in meteorites (also called xenoliths, dark inclusions, clasts, etc.). Unfortunately, most previous studies of these clasts have been misleading, in that these objects have simply been identified as pieces of CM or CI chondrites. In our work we have found this to be generally erroneous, and that CM and especially CI clasts are actually rather rare. We therefore test the hypothesis that these clasts sample the full range of small solar system bodies. We have located and obtained samples of clasts in 81 different meteorites, and have begun a thorough characterization of the bulk compositions, mineralogies, petrographies, and organic compositions of this unique sample set. In addition to the standard e-beam analyses, recent advances in technology now permit us to measure bulk O isotopic compositions, and major- though trace-element compositions of the sub-mm-sized discrete clasts. Detailed characterization of these clasts permit us to explore the full range of mineralogical and petrologic processes in the early solar system, including the nature of fluids in the Kuiper belt and the outer main asteroid belt, as revealed by the mineralogy of secondary phases.

Should the USAF be Involved in Planetary Defense

DTIC Science & Technology

2009-04-01

pebbles.6 The impact of most of these objects can be neglected because of their small size. However, there are plenty of other objects in our solar ...the scientific community of end-bringing objects we know about in our solar system is asteroid Apophasis. Astronomers initially thought for a while...the solar system and could come across the orbit of the earth. The density of these objects also varies greatly. Some meteors are made of an almost

NanoSail-D: A Solar Sail Demonstration Mission

NASA Technical Reports Server (NTRS)

Johnson, Les; Whorton, Mark; Heaton, Andy; Pinson, robin; Laue, Greg; Adams, Charles

2009-01-01

During the past decade, within the United States, NASA Marshall Space Flight Center (MSFC) was heavily engaged in the development of revolutionary new technologies for in-space propulsion. One of the major in-space propulsion technologies developed was a solar sail propulsion system. Solar sail propulsion uses the solar radiation pressure exerted by the momentum transfer of reflected photons to generate a net force on a spacecraft. To date, solar sail propulsion systems have been designed for large spacecraft in the tens to hundreds of kilograms mass range. Recently, however, MSFC has been investigating the application of solar sails for small satellite propulsion. Likewise, NASA Ames Research Center (ARC) has been developing small spacecraft missions that have a need for amass-efficient means of satisfying deorbit requirements. Hence, a synergistic collaboration was established between these two NASA field Centers with the objective of conducting a flight demonstration of solar sail technologies for small satellites. The NanoSail-D mission flew onboard the ill-fated Falcon Rocket launched August 2, 2008, and, due to the failure of that rocket, never achieved orbit. The NanoSail-D flight spare is ready for flight and a suitable launch arrangement is being actively pursued. Both the original sailcraft and the flight spare are hereafter referred to as NanoSail-D. The sailcraft consists of a sail subsystem stowed in a three-element CubeSat. Shortly after deployment of the NanoSail-D, the solar sail will deploy and mission operations will commence. This demonstration flight has two primary technical objectives: (1) to successfully stow and deploy the sail and (2) to demonstrate deorbit functionality. Given a near-term opportunity for launch on Falcon, the project was given the challenge of delivering the flight hardware in 6 mo, which required a significant constraint on flight system functionality. As a consequence, passive attitude stabilization of the spacecraft will be achieved using permanent magnets to detumble and orient the body with the magnetic field lines and then rely on atmospheric drag to passively stabilize the sailcraft in an essentially maximum drag attitude. This paper will present an introduction to solar sail propulsion systems and an overview of the NanoSail-D spacecraft.

Small Solar Electric Propulsion Spacecraft Concept for Near Earth Object and Inner Solar System Missions

NASA Technical Reports Server (NTRS)

Lang, Jared J.; Randolph, Thomas M.; McElrath, Timothy P.; Baker, John D.; Strange, Nathan J.; Landau, Damon; Wallace, Mark S.; Snyder, J. Steve; Piacentine, Jamie S.; Malone, Shane;

Lunar and Planetary Science XXXV: Origin of Planetary Systems

NASA Technical Reports Server (NTRS)

2004-01-01

The session "Origin of Planetary Systems" included the following reports: (12753) Povenmire - Standard Comparison Small Main Belt Asteroid?; Gravitational Frequencies of Extra-Solar Planets; 'Jumping Jupiters' in Binary Star Systems; Hermes, Asteroid 2002 SY50 and the Northern Cetids - No Link Found!; What Kind of Accretion Model is Required for the Solar System; and Use of an Orbital Phase Curve of Extrasolar Planet for Specification of its Mass.

Solar thermal power systems point-focusing thermal and electric applications projects. Volume 1: Executive summary

NASA Technical Reports Server (NTRS)

Marriott, A.

1980-01-01

The activities of the Point-Focusing Thermal and Electric Applications (PETEA) project for the fiscal year 1979 are summarized. The main thrust of the PFTEA Project, the small community solar thermal power experiment, was completed. Concept definition studies included a small central receiver approach, a point-focusing distributed receiver system with central power generation, and a point-focusing distributed receiver concept with distributed power generation. The first experiment in the Isolated Application Series was initiated. Planning for the third engineering experiment series, which addresses the industrial market sector, was also initiated. In addition to the experiment-related activities, several contracts to industry were let and studies were conducted to explore the market potential for point-focusing distributed receiver (PFDR) systems. System analysis studies were completed that looked at PFDR technology relative to other small power system technology candidates for the utility market sector.

Challenges of Communications and Tracking for Solar System Small Body Exploration

NASA Technical Reports Server (NTRS)

Rush, John J.; Lichten, Stephen M.; Srinivasan, Jeffrey M.

2011-01-01

This presentation will address: (1) Communications capabilities that will be needed for space missions for Small Planetary Body exploration (2) Utilization of large ground-based radar capabilities for Small Body remote sensing and mission planning

Nonimaging concentrators for solar thermal energy

NASA Astrophysics Data System (ADS)

Winston, R.; Gallagher, J. J.

1980-03-01

A small experimental solar collector test facility was used to explore applications of nonimaging optics for solar thermal concentration in three substantially different configurations: a single stage system with moderate concentration on an evacuated absorber (a 5.25X evacuated tube Compound Parabolic Concentrator or CPC), a two stage system with high concentration and a non-evacuated absorber (a 16X Fresnel lens/CPC type mirror) and moderate concentration single stage systems with non-evacuated absorbers for lower temperature (a 3X and a 6.5X CPC). Prototypes of each of these systems were designed, built and tested. The performance characteristics are presented.

Spacecraft/Rover Hybrids for the Exploration of Small Solar System Bodies. [NASA NIAC Phase I Study

NASA Technical Reports Server (NTRS)

Pavone, Marco; Castillo-Rogez, Julie C.; Hoffman, Jeffrey A.; Nesnas, Issa A. D.

2012-01-01

This study investigated a novel mission architecture for the systematic and affordable in-situ exploration of small Solar System bodies. Specifically, a mother spacecraft would deploy over the surface of a small body one, or several, spacecraft/rover hybrids, which are small, multi-faceted enclosed robots with internal actuation and external spikes. They would be capable of 1) long excursions (by hopping), 2) short traverses to specific locations (through a sequence of controlled tumbles), and 3) high-altitude, attitude-controlled ballistic flight (akin to spacecraft flight). Their control would rely on synergistic operations with the mother spacecraft (where most of hybrids' perception and localization functionalities would be hosted), which would make the platforms minimalistic and, in turn, the entire mission architecture affordable.

Sino-American cooperation for rural electrification in China

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

Wallace, W.L.; Tsuo, Y.S.; Taylor, R.

1997-12-01

This paper discusses primarily two different renewable energy programs which are in progress in China. One is in Gansu province, based on a solar home system project. This project is stressing a sustainable market development, provision of small lighting systems for residential and small schools, and water pumping and telecommunications support. It seeks involvement of 600 households as a minimum over 18 months. The second project is a very aggressive renewable energy project in Inner Mongolia, where there are excellent wind and solar resources, and where there are already 110,000 small wind turbines installed, in addition to more than 9more » hybrid power systems for villages. These programs have major involvement from the Chinese government and industry, with some guidance and support from the USA.« less

Deployable Mini-Payload Missions Enabled by Small Radioisotope Power Systems (RPSs)

NASA Technical Reports Server (NTRS)

Abelson, Robert D.; Satter, Celeste M.

2005-01-01

Deployable mini-payloads are envisioned as small, simple, standalone instruments that could be deployed from a mother vehicle such as a rover or the proposed Jupiter Icy Moons Orbiter to key points of interest within the solar system. Used in conjunction with a small radioisotope power system (RPS), these payloads could potentially be used for long-duration science missions or as positional beacons for rovers or other spacecraft. The RPS power source would be suitable for deployable mini-payload missions that would take place anywhere there is limited, intermittent, or no solar insolation. This paper introduces two such concepts: (1) a seismic monitoring station deployed by a rover or aerobot, and (2) a passive fields and particles station delivered by a mother spacecraft to Jupiter.

A Small Mission Concept to the Sun-Earth Lagrangian L5 Point for Innovative Solar, Heliospheric and Space Weather Science

NASA Technical Reports Server (NTRS)

Lavraud, B.; Liu, Y.; Segura, K.; He, J.; Qin, G.; Temmer, M.; Vial, J.-C.; Xiong, M.; Davies, J. A.; Rouillard, A. P.;

A small mission concept to the Sun-Earth Lagrangian L5 point for innovative solar, heliospheric and space weather science

NASA Astrophysics Data System (ADS)

Lavraud, B.; Liu, Y.; Segura, K.; He, J.; Qin, G.; Temmer, M.; Vial, J.-C.; Xiong, M.; Davies, J. A.; Rouillard, A. P.; Pinto, R.; Auchère, F.; Harrison, R. A.; Eyles, C.; Gan, W.; Lamy, P.; Xia, L.; Eastwood, J. P.; Kong, L.; Wang, J.; Wimmer-Schweingruber, R. F.; Zhang, S.; Zong, Q.; Soucek, J.; An, J.; Prech, L.; Zhang, A.; Rochus, P.; Bothmer, V.; Janvier, M.; Maksimovic, M.; Escoubet, C. P.; Kilpua, E. K. J.; Tappin, J.; Vainio, R.; Poedts, S.; Dunlop, M. W.; Savani, N.; Gopalswamy, N.; Bale, S. D.; Li, G.; Howard, T.; DeForest, C.; Webb, D.; Lugaz, N.; Fuselier, S. A.; Dalmasse, K.; Tallineau, J.; Vranken, D.; Fernández, J. G.

2016-08-01

We present a concept for a small mission to the Sun-Earth Lagrangian L5 point for innovative solar, heliospheric and space weather science. The proposed INvestigation of Solar-Terrestrial Activity aNd Transients (INSTANT) mission is designed to identify how solar coronal magnetic fields drive eruptions, mass transport and particle acceleration that impact the Earth and the heliosphere. INSTANT is the first mission designed to (1) obtain measurements of coronal magnetic fields from space and (2) determine coronal mass ejection (CME) kinematics with unparalleled accuracy. Thanks to innovative instrumentation at a vantage point that provides the most suitable perspective view of the Sun-Earth system, INSTANT would uniquely track the whole chain of fundamental processes driving space weather at Earth. We present the science requirements, payload and mission profile that fulfill ambitious science objectives within small mission programmatic boundary conditions.

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.

Hot Thermal Storage in a Variable Power, Renewable Energy System

DTIC Science & Technology

2014-06-01

vehicle PV photovoltaic SCES super capacitors energy storage SPIDERS Smart Power Infrastructure Demonstration for Energy Reliability TE thermoelectric ...4  Figure 3.  Photovoltaic solar resources of the United States, from [24]. ...........................9  Figure 4.  Annual...collectors, solar photovoltaic collectors and small wind turbines coupled with facility suitable thermal storage systems. D. LITERATURE REVIEW The

Solar Parabolic Dish Annual Technology Evaluation Report

NASA Technical Reports Server (NTRS)

1983-01-01

The activities of the JPL Solar Thermal Power Systems Parabolic Dish Project for FY 1982 are summarized. Included are discussions on designs of module development including their concentrator, receiver, and power conversion subsystems. Analyses and test results, along with progress on field tests, Small Community Experiment System development, and tests at the Parabolic Dish Test Site are also included.

Efficient structures for geosynchronous spacecraft solar arrays. Phase 1, 2 and 3

NASA Astrophysics Data System (ADS)

Adams, L. R.; Hedgepeth, J. M.

1981-09-01

Structural concepts for deploying and supporting lightweight solar-array blankets for geosynchronous electrical power are evaluated. It is recommended that the STACBEAM solar-array system should be the object of further study and detailed evaluation. The STACBEAM system provides high stiffness at low mass, and with the use of a low mass deployment mechanism, full structural properties can be maintained throughout deployment. The stowed volume of the STACBEAM is acceptably small, and its linear deployment characteristic allows periodic attachments to the solar-array blanket to be established in the stowed configuration and maintained during deployment.

Efficient structures for geosynchronous spacecraft solar arrays. Phase 1, 2 and 3

NASA Technical Reports Server (NTRS)

Adams, L. R.; Hedgepeth, J. M.

1981-01-01

Structural concepts for deploying and supporting lightweight solar-array blankets for geosynchronous electrical power are evaluated. It is recommended that the STACBEAM solar-array system should be the object of further study and detailed evaluation. The STACBEAM system provides high stiffness at low mass, and with the use of a low mass deployment mechanism, full structural properties can be maintained throughout deployment. The stowed volume of the STACBEAM is acceptably small, and its linear deployment characteristic allows periodic attachments to the solar-array blanket to be established in the stowed configuration and maintained during deployment.

Investigations on physics of planetary atmospheres and small bodies of the Solar system, extrasolar planets and disk structures around the stars

NASA Astrophysics Data System (ADS)

Vidmachenko, A. P.; Delets, O. S.; Dlugach, J. M.; Zakhozhay, O. V.; Kostogryz, N. M.; Krushevska, V. M.; Kuznyetsova, Y. G.; Morozhenko, O. V.; Nevodovskyi, P. V.; Ovsak, O. S.; Rozenbush, O. E.; Romanyuk, Ya. O.; Shavlovskiy, V. I.; Yanovitskij, E. G.

2015-12-01

The history and main becoming stages of Planetary system physics Department of the Main astronomical observatory of National academy of Sciences of Ukraine are considered. Fundamental subjects of department researches and science achievements of employees are presented. Fields of theoretical and experimental researches are Solar system planets and their satellites; vertical structures of planet atmospheres; radiative transfer in planet atmospheres; exoplanet systems of Milky Way; stars having disc structures; astronomical engineering. Employees of the department carry out spectral, photometrical and polarimetrical observations of Solar system planets, exoplanet systems and stars with disc structures. 1. From the history of department 2. The main directions of department research 3. Scientific instrumentation 4. Telescopes and observation stations 5. Theoretical studies 6. The results of observations of planets and small Solar system bodies and their interpretation 7. The study of exoplanets around the stars of our galaxy 8. Spectral energy distribution of fragmenting protostellar disks 9. Cooperation with the National Technical University of Ukraine (KPI) and National University of Ukraine "Lviv Polytechnic" to study the impact of stratospheric aerosol changes on weather and climate of the Earth 10. International relations. Scientific and organizational work. Scientific conferences, congresses, symposia 11. The main achievements of the department 12. Current researches 13. Anniversaries and awards

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.

Probable Disastrous Consequences of Collision Between Unknown Small (100 m) Asteroids with Known (Approximately 1 km) Near Earth Orbiting (NEO) Asteroids

NASA Technical Reports Server (NTRS)

Smalley, Larry

2003-01-01

The long-term stability of the Solar System is not well understood. Ironically its stability is taken for granted even though our knowledge of all the constituents [comets, asteroids. (The Asteroid Belt between Mars and Jupiter, Trojan Asteroids, Kuiper belt, Ort Cloud), planetoids, planets, moons, etc], and its long-term dynamics cannot be easily computed. At best one might say that the solar system is chaotic, but much of the time it seems to exists near a quasi-stationary state. An asteroid that passes near the Earth regularly returns with clock-like precision. Taking into account every known detail of its path through the solar system, its orbit is calculated forward thousands of years with no untoward calamity on the horizon. And then one day, this passive visitor slams into the Earth during a sunny afternoon picnic! Can this happen? Unfortunately, this is a real possibility in the ordinary history of the solar system. In fact our knowledge of the solar system in the small is sketchy, as will be pointed out. Events, which lie outside our awareness, can precipitate disasters that we may perceive when it's too late to launch effective counter measures. In this work, one such scenario is described and the direct consequences for the Earth are calculated.

Early accretion of water and volatile elements to the inner Solar System: evidence from angrites

NASA Astrophysics Data System (ADS)

Sarafian, Adam R.; Hauri, Erik H.; McCubbin, Francis M.; Lapen, Thomas J.; Berger, Eve L.; Nielsen, Sune G.; Marschall, Horst R.; Gaetani, Glenn A.; Righter, Kevin; Sarafian, Emily

2017-04-01

Inner Solar System bodies are depleted in volatile elements relative to chondrite meteorites, yet the source(s) and mechanism(s) of volatile-element depletion and/or enrichment are poorly constrained. The timing, mechanisms and quantities of volatile elements present in the early inner Solar System have vast implications for diverse processes, from planetary differentiation to the emergence of life. We report major, trace and volatile-element contents of a glass bead derived from the D'Orbigny angrite, the hydrogen isotopic composition of this glass bead and that of coexisting olivine and silicophosphates, and the 207Pb-206Pb age of the silicophosphates, 4568 ± 20 Ma. We use volatile saturation models to demonstrate that the angrite parent body must have been a major body in the early inner Solar System. We further show via mixing calculations that all inner Solar System bodies accreted volatile elements with carbonaceous chondrite H and N isotope signatures extremely early in Solar System history. Only a small portion (if any) of comets and gaseous nebular H species contributed to the volatile content of the inner Solar System bodies. This article is part of the themed issue 'The origin, history and role of water in the evolution of the inner Solar System'.

Early accretion of water and volatile elements to the inner Solar System: evidence from angrites.

PubMed

Sarafian, Adam R; Hauri, Erik H; McCubbin, Francis M; Lapen, Thomas J; Berger, Eve L; Nielsen, Sune G; Marschall, Horst R; Gaetani, Glenn A; Righter, Kevin; Sarafian, Emily

2017-05-28

Inner Solar System bodies are depleted in volatile elements relative to chondrite meteorites, yet the source(s) and mechanism(s) of volatile-element depletion and/or enrichment are poorly constrained. The timing, mechanisms and quantities of volatile elements present in the early inner Solar System have vast implications for diverse processes, from planetary differentiation to the emergence of life. We report major, trace and volatile-element contents of a glass bead derived from the D'Orbigny angrite, the hydrogen isotopic composition of this glass bead and that of coexisting olivine and silicophosphates, and the 207 Pb- 206 Pb age of the silicophosphates, 4568 ± 20 Ma. We use volatile saturation models to demonstrate that the angrite parent body must have been a major body in the early inner Solar System. We further show via mixing calculations that all inner Solar System bodies accreted volatile elements with carbonaceous chondrite H and N isotope signatures extremely early in Solar System history. Only a small portion (if any) of comets and gaseous nebular H species contributed to the volatile content of the inner Solar System bodies.This article is part of the themed issue 'The origin, history and role of water in the evolution of the inner Solar System'. © 2017 The Author(s).

Solar electric power for instruments at remote sites

USGS Publications Warehouse

McChesney, P.J.

2000-01-01

Small photovoltaic (PV) systems are the preferred method to power instruments operating at permanent locations away from the electric power grid. The low-power PV power system consists of a solar panel or small array of panels, lead-acid batteries, and a charge controller. Even though the small PV power system is simple, the job of supplying power at a remote site can be very demanding. The equipment is often exposed to harsh conditions. The site may be inaccessible part of the year or difficult and expensive to reach at any time. Yet the system must provide uninterrupted power with minimum maintenance at low cost. This requires good design. Successful small PV systems often require modifications by a knowledgeable fieldworker to adapt to conditions at the site. Much information is available in many places about solar panels, lead-acid batteries, and charging systems but very little of it applies directly to low power instrument sites. The discussion here aims to close some of the gap. Each of the major components is described in terms of this application with particular attention paid to batteries. Site problems are investigated. Finally, maintenance and test procedures are given. This document assumes that the reader is engaged in planning or maintaining low-power PV sites and has basic electrical and electronic knowledge. The area covered by the discussion is broad. To help the reader with the many terms and acronyms used, they are shown in bold when first used and a glossary is provided at the end of the paper.

The performance of solar thermal electric power systems employing small heat engines

NASA Technical Reports Server (NTRS)

Pons, R. L.

1980-01-01

The paper presents a comparative analysis of small (10 to 100 KWe) heat engines for use with a solar thermal electric system employing the point-focusing, distributed receiver (PF-DR) concept. Stirling, Brayton, and Rankine cycle engines are evaluated for a nominal overall system power level of 1 MWe, although the concept is applicable to power levels up to at least 10 MWe. Multiple concentrators are electrically connected to achieve the desired plant output. Best performance is achieved with the Stirling engine, resulting in a system Levelized Busbar Energy Cost of just under 50 mills/kWH and a Capital Cost of $900/kW, based on the use of mass-produced components. Brayton and Rankine engines show somewhat less performance but are viable alternatives with particular benefits for special applications. All three engines show excellent performance for the small community application.

SPS market analysis. [small solar thermal power systems

NASA Technical Reports Server (NTRS)

Goff, H. C.

1980-01-01

A market analysis task included personal interviews by GE personnel and supplemental mail surveys to acquire statistical data and to identify and measure attitudes, reactions and intentions of prospective small solar thermal power systems (SPS) users. Over 500 firms were contacted, including three ownership classes of electric utilities, industrial firms in the top SIC codes for energy consumption, and design engineering firms. A market demand model was developed which utilizes the data base developed by personal interviews and surveys, and projected energy price and consumption data to perform sensitivity analyses and estimate potential markets for SPS.

Efficient use of land to meet sustainable energy needs

NASA Astrophysics Data System (ADS)

Hernandez, Rebecca R.; Hoffacker, Madison K.; Field, Christopher B.

2015-04-01

The deployment of renewable energy systems, such as solar energy, to achieve universal access to electricity, heat and transportation, and to mitigate climate change is arguably the most exigent challenge facing humans today. However, the goal of rapidly developing solar energy systems is complicated by land and environmental constraints, increasing uncertainty about the future of the global energy landscape. Here, we test the hypothesis that land, energy and environmental compatibility can be achieved with small- and utility-scale solar energy within existing developed areas in the state of California (USA), a global solar energy hotspot. We found that the quantity of accessible energy potentially produced from photovoltaic (PV) and concentrating solar power (CSP) within the built environment (`compatible’) exceeds current statewide demand. We identify additional sites beyond the built environment (`potentially compatible’) that further augment this potential. Areas for small- and utility-scale solar energy development within the built environment comprise 11,000-15,000 and 6,000 TWh yr-1 of PV and CSP generation-based potential, respectively, and could meet the state of California’s energy consumptive demand three to five times over. Solar energy within the built environment may be an overlooked opportunity for meeting sustainable energy needs in places with land and environmental constraints.

Advanced Solar-propelled Cargo Spacecraft for Mars Missions

NASA Technical Reports Server (NTRS)

Auziasdeturenne, Jacqueline; Beall, Mark; Burianek, Joseph; Cinniger, Anna; Dunmire, Barbrina; Haberman, Eric; Iwamoto, James; Johnson, Stephen; Mccracken, Shawn; Miller, Melanie

1989-01-01

Three concepts for an unmanned, solar powered, cargo spacecraft for Mars support missions were investigated. These spacecraft are designed to carry a 50,000 kg payload from a low Earth orbit to a low Mars orbit. Each design uses a distinctly different propulsion system: A Solar Radiation Absorption (SRA) system, a Solar-Pumped Laser (SPL) system and a solar powered magnetoplasmadynamic (MPD) arc system. The SRA directly converts solar energy to thermal energy in the propellant through a novel process. In the SPL system, a pair of solar-pumped, multi-megawatt, CO2 lasers in sunsynchronous Earth orbit converts solar energy to laser energy. The MPD system used indium phosphide solar cells to convert sunlight to electricity, which powers the propulsion system. Various orbital transfer options are examined for these concepts. In the SRA system, the mother ship transfers the payload into a very high Earth orbit and a small auxiliary propulsion system boosts the payload into a Hohmann transfer to Mars. The SPL spacecraft and the SPL powered spacecraft return to Earth for subsequent missions. The MPD propelled spacecraft, however, remains at Mars as an orbiting space station. A patched conic approximation was used to determine a heliocentric interplanetary transfer orbit for the MPD propelled spacecraft. All three solar-powered spacecraft use an aerobrake procedure to place the payload into a low Mars parking orbit. The payload delivery times range from 160 days to 873 days (2.39 years).

Advanced Solar Receivers

NASA Technical Reports Server (NTRS)

Owen, W. A.

1984-01-01

Low thermal efficiencies in solar receivers are discussed in terms of system design. It is recommended that careful attention be given to the overall thermal systems design, especially to conductive losses about the window and areas of relatively thin insulation. If the cavity design is carefully managed to insure a small, minimally reradiating aperture, the goal of a very high efficiency cavity receiver is a realistic one.

Long-Term Dynamics of Small Bodies in the Solar System

NASA Technical Reports Server (NTRS)

Saunders, Steve (Technical Monitor); Holman, Matthew J.

2005-01-01

As part of the NASA Planetary Geology and Geophysics program Prof. Norm Murray (CITA) and I have been conducting investigations of the long-term dynamics of small bodies in the outer solar system. This grant, and its predecessor NAG5-7761, supported travel for collaboration by the Investigators and also supports Murray during an annual one month visit to the CfA for further collaboration. In the course of this grant we made a number of advances in solar system dynamics. For example, we developed an analytic model for the origin and consequence of chaos associated with three-body resonances in the asteroid belt. This has been shown to be important for the delivery of near Earth objects. We later extended this model to three-body resonances among planets. We were able to show that the numerically identified chaos among the outer planets results from a three-body resonance involving Jupiter, Saturn, and Uranus. The resulting paper was awarded the 1999 Newcomb Cleveland award from the AAAS. This award singles out one paper published in Science each year for distinction. This grant has also supported, in part, my participate in other solar system dynamics projects. The results from those collaborations are also listed.

A 'two-tank' seasonal storage concept for solar space heating of buildings

NASA Astrophysics Data System (ADS)

Cha, B. K.; Connor, D. W.; Mueller, R. O.

This paper presents an analysis of a novel 'two-tank' water storage system, consisting of a large primary water tank for seasonal storage of solar energy plus a much smaller secondary water tank for storage of solar energy collected during the heating season. The system offers the advantages of high collection efficiency during the early stages of the heating season, a period when the temperature of the primary tank is generally high. By preferentially drawing energy from the small secondary tank to meet load, its temperature can be kept well below that of the larger primary tank, thereby providing a lower-temperature source for collector inlet fluid. The resulting improvement in annual system efficiency through the addition of a small secondary tank is found to be substantial - for the site considered in the paper (Madison, Wisconsin), the relative percentage gain in annual performance is in the range of 10 to 20%. A simple computer model permits accurate hour-by-hour transient simulation of thermal performance over a yearly cycle. The paper presents results of detailed simulations of collectors and storage sizing and design trade-offs for solar energy systems supplying 90% to 100% of annual heating load requirements.

An analysis of thrust of a realistic solar sail with focus on a flight validation mission in a geocentric orbit

NASA Astrophysics Data System (ADS)

Campbell, Bruce A.

Several scientifically important space flight missions have been identified that, at this time, can only be practically achieved using a solar sail propulsion system. These missions take advantage of the potentially continuous force on the sail, provided by solar radiation, to produce significant changes in the spacecraft's velocity, in both magnitude and/or direction, without the need for carrying the enormous amount of fuel that conventional propulsion systems would require to provide the same performance. However, to provide thrust levels that would support these missions requires solar sail areas in the (tens of) thousands of square meter sizes. To realize this, many technical areas must be developed further and demonstrated in space before solar sails will be accepted as a viable space mission propulsion system. One of these areas concerns understanding the propulsion performance of a realistic solar sail well enough for mission planning. Without this understanding, solar sail orbits could not be predicted well enough to meet defined mission requirements, such as rendezvous or station-keeping, and solar sail orbit optimization, such as minimizing flight time, could be close to impossible. In most mission studies, either an "ideal" sail's performance is used for mission planning, or some top-level assumptions of certain nonideal sail characteristics are incorporated to give a slightly better estimate of the sail performance. This paper identifies the major sources of solar sail thrust performance uncertainty, and analyzes the most significant ones to provide a more comprehensive understanding of thrust generation by a "realistic" solar sail. With this understanding, mission planners will be able to more confidently and accurately estimate the capabilities of such a system. The first solar sail mission will likely be a system validation mission, using a relatively small sail in a geocentric (Earth-centered) orbit. The author has been involved in conceptual design of such missions, and through this became aware of the current status in solar sail system development, and the need for a better understanding of the thrust performance of a "realistic" solar sail. Such a validation mission is significantly different than most of the "operational" science missions envisioned to utilize a solar sail propulsion system. These future missions will likely use very large, very light sails in heliocentric orbits far away from major gravity fields like planets, have very long mission lifetimes (years), and will conduct relatively minor and slow orbital and attitude control maneuvers. Nonetheless, most of the capabilities of later systems can be gleaned from a small geocentric validation mission. This paper is a significant step toward understanding the thrust characteristics and performance of a realistic solar sail, and provides insight to the methods by which this understanding can be corroborated by a solar sail validation mission.

Transformative Small Body Science Enabled with Pan-STARSS Survey Data

NASA Astrophysics Data System (ADS)

Meech, Karen J.; Kleyna, Jan T.; Keane, Jacqueline V.; Hainaut, Olivier R.; MIcheli, Marco

2018-01-01

In the first 5 Myr of Solar System formation, gas imprinted a local chemical signature on the planetesimals which were subsequently redistributed during planet formation. Decades-long ground- and space-based studies have tried to map our solar system’s protoplanetary disk chemistry using volatiles in comets. We now know that comet volatiles (H2O, CO, CO2 and organics) have distinct chemical classes. This data contradicts traditional ideas that all volatile-rich bodies formed in the outer disk. In-situ space comet missions have suggested, however, that comets preserve their pristine volatile inventory, and perhaps even their heritage of ices prior to the protoplanetary disk. Recently, a profusion of dynamical models has been developed that can reproduce some of the key characteristics of today’s solar system. Some models require significant giant planet migration, while others do not. The UH-led Pan-STARRS1 survey (PS1) can offer transformative insight into small bodies and the early solar system, providing a preview of LSST. In 2013 PS1 discovered an asteroidal object on a long-period comet orbit, the first of a class of tailless objects informally called Manxes. The second Manx discovered had a surface composition similar to inner solar system rocky S-type material, suggesting the intriguing possibility that we are looking at fresh inner solar system Earth-forming material, preserved for billions of years in the Oort cloud. Currently 10-15 of these objects are discovered each year, with PS1 dominating the discoveries. The number of rocky inner solar system Manx objects can be used to constrain solar system formation models. PS1 is also very good at discovering faint active objects at large distances, including the remarkable discovery of a comet active beyond 16 au from the sun. By searching the PS1 database once these discoveries are made, it is possible to extend the orbit arc backwards in time, allowing us to model the activity, and understand the chemistry and physics of ices and activity in the outer solar system. These discoveries will help us tie together chemistry and dynamics in our solar system with new resolved ALMA observations of protoplanetary disks. Support from NSF grants AST-1617015, 1413736.

An Investigation of the Effectiveness of Solar Power on Navy Surface Combatants

DTIC Science & Technology

2013-09-01

addition , this could cause a measureable reduction in the Navy’s environmental impact, especially since solar power can be generated both when the ships...that a relatively small addition in overall ship’s displacement would be required to implement a solar power system. Additionally, the solar cells...as a source of pulse power for large electrical loads such as high - energy weapons or radars. Both these applications are well within the current

Solar array maximum power tracking with closed-loop control of a 30-centimeter ion thruster

NASA Technical Reports Server (NTRS)

Gruber, R. P.

1977-01-01

A new solar array/ion thruster system control concept has been developed and demonstrated. An ion thruster beam load is used to automatically and continuously operate an unregulated solar array at its maximum power point independent of variations in solar array voltage and current. Preliminary tests were run which verified that this method of control can be implemented with a few, physically small, signal level components dissipating less than two watts.

First Results of the Near Real-Time Imaging Reconstruction System at Big Bear Solar Observatory

NASA Astrophysics Data System (ADS)

Yang, G.; Denker, C.; Wang, H.

2003-05-01

The Near Real-Time Imaging Reconstruction system (RTIR) at Big Bear Solar Observatory (BBSO) is designed to obtain high spatial resolution solar images at a cadence of 1 minute utilizing the power of parallel processing. With this system, we can compute near diffraction-limited images without saving huge amounts of data that are involved in the speckle masking reconstruction algorithm. It enables us to monitor active regions and give fast response to the solar activity. In this poster we present the first results of our new 32-CPU Beowulf cluster system. The images are 1024 x 1024 and the field of view (FOV) is 80'' x 80''. Our target is an active region with complex magnetic configuration. We focus on pores and small spots in the active region with the goal of better understanding the formation of penumbra structure. In addition we expect to study evolution of active regions during solar flares.

Why we need asteroid sample return mission?

NASA Astrophysics Data System (ADS)

Barucci, Maria Antonietta

2016-07-01

Small bodies retain evidence of the primordial solar nebula and the earliest solar system processes that shaped their evolution. They may also contain pre-solar material as well as complex organic molecules, which could have a major role to the development of life on Earth. For these reasons, asteroids and comets have been targets of interest for missions for over three decades. However, our knowledge of these bodies is still very limited, and each asteroid or comet visited by space mission has revealed unexpected scientific results, e.g. the structure and nature of comet 67P/Churyumov-Gerasimenko (67P/C-G) visited by the Rosetta mission. Only in the laboratory can instruments with the necessary precision and sensitivity be applied to individual components of the complex mixture of materials that forms a small body regolith, to determine their precise chemical and isotopic composition. Such measurements are vital for revealing the evidence of stellar, interstellar medium, pre-solar nebula and parent body processes that are retained in primitive material, unaltered by atmospheric entry or terrestrial contamination. For those reasons, sample return missions are considered a high priority by a number of the leading space agencies. Abundant within the inner Solar System and the main impactors on terrestrial planets, small bodies may have been the principal contributors of the water and organic material essential to create life on Earth. Small bodies can therefore be considered to be equivalent to DNA for unravelling our solar system's history, offering us a unique window to investigate both the formation of planets and the origin of life. A sample return mission to a primitive Near-Earth Asteroid (NEA) has been study at ESA from 2008 in the framework of ESA's Cosmic Vision (CV) programme, with the objective to answer to the fundamental CV questions "How does the Solar System work?" and "What are the conditions for life and planetary formations?". The returned material will allow us to study in terrestrial laboratories some of the most primitive materials available to investigate early solar system formation processes, to explore initial stages of habitable planet formation, to identify and characterize the organics and volatiles in a primitive asteroid. The ideal easy target body for such mission is a D type NEA. D types are the most abundant asteroids beyond the outer edge of the main belt. It is likely that they formed much further out in the Solar System, possibly as far as the transneptunian objects, and were subsequently captured in their present locations following the migration of the gas giants. Spectral features indicate that these bodies are organic rich, contain fine anhydrous minerals but also may be volatile rich and appear to be the most primitive rocky material present in the solar system. In addition to addressing the major science goals, sample return mission from a NEA also involved innovative European technologies. The key sample return capabilities, i.e. asteroid navigation, touch and go, sampling mechanism and the re-entry capsule have reached at ESA a validation status to enter implementation phase. The development of sample return technology represents in Europe a crucial element for planetary science and for the space technology development.

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.

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.

Origin of Outer Solar System

NASA Technical Reports Server (NTRS)

Holman, Matthew J.; Lindstrom, David (Technical Monitor)

2005-01-01

Our ongoing research program combines extensive deep and wide-field observations using a variety of observational platforms with numerical studies of the dynamics of small bodies in the outer solar system in order to advance the main scientific goals of the community studying the Kuiper belt and the outer solar system. These include: (1) determining the relative populations of the known classes of KBOs as well as other possible classes; ( 2 ) determining the size distributions or luminosity function of the individual populations or the Kuiper belt as a whole; (3) determining the inclinations distributions of these populations; (4) establishing the radial extent of the Kuiper belt; ( 5 ) measuring and relating the physical properties of different types of KBOs to those of other solar system bodies; and, (6) completing our systematic inventory of the satellites of the outer planets.

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

An innovative deployable solar panel system for Cubesats

NASA Astrophysics Data System (ADS)

Santoni, Fabio; Piergentili, Fabrizio; Donati, Serena; Perelli, Massimo; Negri, Andrea; Marino, Michele

2014-02-01

One of the main Cubesat bus limitations is the available on-board power. The maximum power obtained using body mounted solar panels and advanced triple junction solar cells on a triple unit Cubesat is typically less than 10 W. The Cubesat performance and the mission scenario opened to these small satellite systems could be greatly enhanced by an increase of the available power. This paper describes the design and realization of a modular deployable solar panel system for Cubesats, consisting of a modular hinge and spring system that can be potentially used on-board single (1U), double(2U), triple (3U) and six units (6U) Cubesats. The size of each solar panels is the size of a lateral Cubesat surface. The system developed is the basis for a SADA (Solar Array Drive Assembly), in which a maneuvering capability is added to the deployed solar array in order to follow the apparent motion of the sun. The system design trade-off is discussed, comparing different deployment concepts and architectures, leading to the final selection for the modular design. A prototype of the system has been realized for a 3U Cubesat, consisting of two deployable solar panel systems, made of three solar panels each, for a total of six deployed solar panels. The deployment system is based on a plastic fiber wire and thermal cutters, guaranteeing a suitable level of reliability. A test-bed for the solar panel deployment testing has been developed, supporting the solar array during deployment reproducing the dynamical situation in orbit. The results of the deployment system testing are discussed, including the design and realization of the test-bed, the mechanical stress given to the solar cells by the deployment accelerations and the overall system performance. The maximum power delivered by the system is about 50.4 W BOL, greatly enhancing the present Cubesat solar array performance.

Kinetic Interactions Between the Solar Wind and Lunar Magnetic Fields

NASA Astrophysics Data System (ADS)

Halekas, J. S.; Poppe, A. R.; Fatemi, S.; Turner, D. L.; Holmstrom, M.

2016-12-01

Despite their relatively weak strength, small scale, and incoherence, lunar magnetic anomalies can affect the incoming solar wind flow. The plasma interaction with lunar magnetic fields drives significant compressions of the solar wind plasma and magnetic field, deflections of the incoming flow, and a host of plasma waves ranging from the ULF to the electrostatic range. Recent work suggests that the large-scale features of the solar wind-magnetic anomaly interactions may be driven by ion-ion instabilities excited by reflected ions, raising the possibility that they are analogous to ion foreshock phenomena. Indeed, despite their small scale, many of the phenomena observed near lunar magnetic anomalies appear to have analogues in the foreshock regions of terrestrial planets. We discuss the charged particle distributions, fields, and waves observed near lunar magnetic anomalies, and place them in a context with the foreshocks of the Earth, Mars, and other solar system objects.

The carbon budget in the outer solar nebula

NASA Technical Reports Server (NTRS)

Simonelli, Damon P.; Pollack, James B.; Mckay, Christopher P.; Reynolds, Ray T.; Summers, Audrey L.

1989-01-01

The compositional contrast between the giant-planet satellites and the significantly rockier Pluto/Charon system is indicative of different formation mechanisms; cosmic abundance calculations, in conjunction with an assumption of the Pluto/Charon system's direct formation from solar nebula condensates, strongly suggest that most of the carbon in the outer solar nebula was in CO form, in keeping with both the inheritance from the dense molecular clouds in the interstellar medium, and/or the Lewis and Prinn (1980) kinetic-inhibition model of solar nebula chemistry. Laboratory studies of carbonaceous chondrites and Comet Halley flyby studies suggest that condensed organic material, rather than elemental carbon, is the most likely candidate for the small percentage of the carbon-bearing solid in the outer solar nebula.

Coupled orbit-attitude dynamics and relative state estimation of spacecraft near small Solar System bodies

NASA Astrophysics Data System (ADS)

Misra, Gaurav; Izadi, Maziar; Sanyal, Amit; Scheeres, Daniel

2016-04-01

The effects of dynamical coupling between the rotational (attitude) and translational (orbital) motion of spacecraft near small Solar System bodies is investigated. This coupling arises due to the weak gravity of these bodies, as well as solar radiation pressure. The traditional approach assumes a point-mass spacecraft model to describe the translational motion of the spacecraft, while the attitude motion is considered to be completely decoupled from the translational motion. The model used here to describe the rigid-body spacecraft dynamics includes the non-uniform rotating gravity field of the small body up to second degree and order along with the attitude dependent terms, solar tide, and solar radiation pressure. This model shows that the second degree and order gravity terms due to the small body affect the dynamics of the spacecraft to the same extent as the orbit-attitude coupling due to the primary gravity (zeroth order) term. Variational integrators are used to simulate the dynamics of both the rigid spacecraft and the point mass. The small bodies considered here are modeled after Near-Earth Objects (NEO) 101955 Bennu, and 25143 Itokawa, and are assumed to be triaxial ellipsoids with uniform density. Differences in the numerically obtained trajectories of a rigid spacecraft and a point mass are then compared, to illustrate the impact of the orbit-attitude coupling on spacecraft dynamics in proximity of small bodies. Possible implications on the performance of model-based spacecraft control and on the station-keeping budget, if the orbit-attitude coupling is not accounted for in the model of the dynamics, are also discussed. An almost globally asymptotically stable motion estimation scheme based solely on visual/optical feedback that estimates the relative motion of the asteroid with respect to the spacecraft is also obtained. This estimation scheme does not require a model of the dynamics of the asteroid, which makes it perfectly suited for asteroids whose properties are not well known.

A Big Year for Small Bodies

NASA Astrophysics Data System (ADS)

Mayo, Louis; Erickson, K.

2013-10-01

2013 is a watershed year for celestial events involving the solar system’s unsung heroes, small bodies. The Cosmic Valentine of Asteroid 2012 DA14 which passed within ~ 3.5 Earth radii of the Earth's surface (February 15, 2013), Comet C/2011 L4 PANSTARRS and the Thanksgiving 2013 pass of Comet ISON, which will pass less than 0.012 AU (1.8 million km) from the solar surface and could be visible during the day. All this in addition to Comet Lemmon and a host of meteor showers makes 2013 a landmark year to deliver the excitement of planetary science to the audiences worldwide. To deliver the excitement and wonder of our solar system’s small bodies to worldwide audiences, NASA’s JPL and GSFC education teams in partnership with NASA EDGE will reach out to the public through multiple venues including broadcast media, social media, science and math focused educational activities, observing challenges, interactive visualization tools like “Eyes on the Solar System” and more culminating in the Thanksgiving Day Comet ISON perihelion passage. This talk will highlight NASA’s focused education effort to engage the public in small bodies science and the role these objects play in our understanding of the formation and evolution of the solar system.

What Do Millimeter Continuum and Spectral Line Observations Tell Us about Solar System Bodies?

NASA Technical Reports Server (NTRS)

Milam, Stefanie N.

2013-01-01

Solar system objects are generally cold and radiate at low frequencies and tend to have strong molecular rotational transitions. Millimeter continuum and spectral line observations provide detailed information for nearly all solar system bodies. At these wavelengths, details of the bulk physical composition of icy surfaces, the size and albedo of small objects, the composition of planetary atmospheres can be measured as well as monitoring of time variable phenomena for extended periods (not restricted to nighttime observations), etc. Major issues in solar system science can be addressed by observations in the millimeter/sub-millimeter regime such as the origin of the solar system (isotope ratios, composition) and the evolution of solar system objects (dynamics, atmospheric constituents, etc). ALMA s exceptional sensitivity, large spectral bandwidth, high spectral resolution, and angular resolution (down to 10 milliarcsec) will enable researchers for the first time to better resolve the smallest bodies in the solar system and provide detailed maps of the larger objects. Additionally, measurements with nearly 8 GHz of instantaneous bandwidth to fully characterize solar system object s spectrum and detect trace species. The spatial information and line profiles can be obtained over 800 GHz of bandwidth in 8 receiver bands to not only assist in the identification of spectral lines and emission components for a given species but also to help elucidate the chemistry of the extraterrestrial bodies closest to us.

Heat pumps could inject life into solar energy

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

Butler, P.

1977-07-14

Prospects for the use of solar energy in Great Britain are discussed. The only economically feasible solar system is considered to be a solar assisted heat pump. One of the factors included in an economic assessment of the solar system include the degree to which the house is insulated. Government incentives were suggested to increase solar consumerism. Detailed calculations showed that solar collectors on small British houses were currently uneconomical. The most promising market for solar collectors is outside the domestic market. The lack of standardization of solar collectors also is a hindrance to public acceptance of solar. Heat pumpsmore » with a coefficient of performance of 3:1 and giving a heat output of 3 kW for every 1 kW of electricity are considered economically feasible. Wind powered heat pumps are considered. Estimates of future heat pump use are as high as 30% of the domestic heating market. The US is considered technically more advanced than Britain for many types of solar applications. Technology of solar cells in the United States as opposed to Britain is also discussed.« less

Thermal Storage Applications Workshop. Volume 1: Plenary Session Analysis

NASA Technical Reports Server (NTRS)

1979-01-01

The importance of the development of inexpensive and efficient thermal and thermochemical energy storage technology to the solar power program is discussed in a summary of workship discussions held to exchange information and plan for future systems. Topics covered include storage in central power applications such as the 10 MW-e demonstration pilot receiver to be constructed in Barstow, California; storage for small dispersed systems, and problems associated with the development of storage systems for solar power plants interfacing with utility systems.

Solar Electricity

NASA Technical Reports Server (NTRS)

1988-01-01

ARCO Solar manufactures PV Systems tailored to a broad variety of applications. PV arrays are routinely used at remote communications installations to operate large microwave repeaters, TV and radio repeaters rural telephone, and small telemetry systems that monitor environmental conditions. Also used to power agricultural water pumping systems, to provide electricity for isolated villages and medical clinics, for corrosion protection for pipelines and bridges, to power railroad signals, air/sea navigational aids, and for many types of military systems. ARCO is now moving into large scale generation for utilities.

Chaotic Motion in the Solar System and Beyond

NASA Technical Reports Server (NTRS)

Lissauer, Jack; DeVincenzi, Donald (Technical Monitor)

2001-01-01

The motion of planetary bodies is the archetypal clockwork system. Indeed, clocks and calendars were developed to keep track of the relative motions of the Earth, the Sun and the Moon. However, studies over the past few decades imply that this predictable regularity does not extend to small bodies, nor does it apply to the precise trajectories of the planets themselves over long timescale.s. Various examples of chaotic motion within our Solar System and, extrasolar planetary systems will be discussed.

Anchoring Technology for In Situ Exploration of Small Bodie

NASA Technical Reports Server (NTRS)

Steltzner, A.; Nasif, A.

2000-01-01

Comets, asteroids and other small bodies found in the solar system do not possess enough gravity to ensure spacecraft contact forces sufficient to allow many types of in situ science, such as core or surface sampling.

Method of determining the orbits of the small bodies in the solar system based on an exhaustive search of orbital planes

NASA Astrophysics Data System (ADS)

Bondarenko, Yu. S.; Vavilov, D. E.; Medvedev, Yu. D.

2014-05-01

A universal method of determining the orbits of newly discovered small bodies in the Solar System using their positional observations has been developed. The proposed method suggests determining geocentric distances of a small body by means of an exhaustive search for heliocentric orbital planes and subsequent determination of the distance between the observer and the points at which the chosen plane intersects with the vectors pointing to the object. Further, the remaining orbital elements are determined using the classical Gauss method after eliminating those heliocentric distances that have a fortiori low probabilities. The obtained sets of elements are used to determine the rms between the observed and calculated positions. The sets of elements with the least rms are considered to be most probable for newly discovered small bodies. Afterwards, these elements are improved using the differential method.

Aperture Shield Materials Characterized and Selected for Solar Dynamic Space Power System

NASA Technical Reports Server (NTRS)

1995-01-01

The aperture shield in a solar dynamic space power system is necessary to prevent thermal damage to the heat receiver should the concentrated solar radiation be accidentally or intentionally focused outside of the heat receiver aperture opening and onto the aperture shield itself. Characterization of the optical and thermal properties of candidate aperture shield materials was needed to support the joint U.S./Russian solar dynamic space power effort for Mir. The specific objective of testing performed at the NASA Lewis Research Center was to identify a high-temperature material with a low specular reflectance, a low solar absorptance, and a high spectral emittance so that during an off-pointing event, the amount of solar energy reflecting off the aperture shield would be small, the ratio of solar absorptance to spectral emittance would provide the lowest possible equilibrium temperature, and the integrity of the aperture shield would remain intact.

Social and Economic Impact of Solar Electricity at Schuchuli Village

NASA Technical Reports Server (NTRS)

Bifano, W. J.; Ratajczak, A. F.; Bahr, D. M.; Garrett, B. G.

1979-01-01

Schuchuli, a small remote village on the Papago Indian Reservation in southwest Arizona, is 27 kilometers (17 miles) from the nearest available utility power. Its lack of conventional power is due to the prohibitive cost of supplying a small electrical load with a long-distance distribution line. Furthermore, alternate energy sources are expensive and place a burden on the resources of the villagers. On December 16, 1978, as part of a federally funded project, a solar cell power system was put into operation at Schuchuli. The system powers the village water pump, lighting for homes and other village buildings, family refrigerators and a communal washing machine and sewing machine.

Numerical Study on Radiation Effects to Evaporator in Natural Vacuum Solar Desalination System

NASA Astrophysics Data System (ADS)

Siregar, R. E. T.; Ronowikarto, A. D.; Setyawan, E. Y.; Ambarita, H.

2018-01-01

The need for clean water is increasing day by day due to the increasing factor of living standard of mankind, hence designed natural vacuum solar desalination. The natural vacuum Solar desalination is studied experimentally. A small-scale natural vacuum desalination study consists of evaporator and condenser as the main components designed and manufactured. To transfer heat from the solar collector into the evaporator, the fluid transfer system uses a pump powered by a solar cell. Thus, solar collectors are called hybrid solar collectors. The main purpose of this exposure is to know the characteristics of the radiation effects on incoming energy on the evaporator during the process. This system is tested by exposing the unit to the solar radiation in the 4th floor building in Medan. The experiment was conducted from 8.00 to 16.00 local time. The results show that natural vacuum solar desalination with hybrid solar collectors can be operated perfectly. If the received radiation is high, then the incoming energy received by the evaporator will also be high. From measurements with HOBO microstation, obtained the highest radiation 695.6 W/m2, and the calculation result of incoming energy received evaporator obtained highest result 1807.293 W.

Assessment of distributed solar power systems: Issues and impacts

NASA Astrophysics Data System (ADS)

Moyle, R. A.; Chernoff, H.; Schweizer, T. C.; Patton, J. B.

1982-11-01

The installation of distributed solar-power systems presents electric utilities with a host of questions. Some of the technical and economic impacts of these systems are discussed. Among the technical interconnect issues are isolated operation, power quality, line safety, and metering options. Economic issues include user purchase criteria, structures and installation costs, marketing and product distribution costs, and interconnect costs. An interactive computer program that allows easy calculation of allowable system prices and allowable generation-equipment prices was developed as part of this project. It is concluded that the technical problems raised by distributed solar systems are surmountable, but their resolution may be costly. The stringent purchase criteria likely to be imposed by many potential system users and the economies of large-scale systems make small systems (less than 10 to 20 kW) less attractive than larger systems. Utilities that consider life-cycle costs in making investment decisions and third-party investors who have tax and financial advantages are likely to place the highest value on solar-power systems.

PHOBOS Exploration using Two Small Solar Electric Propulsion (SEP) Spacecraft

NASA Technical Reports Server (NTRS)

Lang, J. J.; Baker, J. D.; McElrath, T. P.; Piacentine, J. S.; Snyder, J. S.

2012-01-01

Phobos Surveyor Mission concept provides an innovative low cost, highly reliable approach to exploring the inner solar system 1/16/2013 3 Dual manifest launch. Use only flight proven, well characterize commercial off-the-shelf components. Flexible mission architecture allows for a slew of unique measurements.

Terrestrial record of the solar system's oscillation about the galactic plane

NASA Technical Reports Server (NTRS)

Stothers, R. B.

1985-01-01

A new study is presented of the observational evidence pertaining to the theory which attributes the episodic component of the earth's impact cratering record over the past 600 Myr to gravitational encounters between the solar system and interstellar clouds that cause comets to fall into the solar system and impact the earth. Contrary to a claim by Thaddeus and Chanan (1985), the vertical scale height of the clouds seems to be sufficently small and the sun's vertical trajectory sufficiently large for the modulating effect of the sun's galactovertical motion to be detectable in the terrestrial record of impact cratering with at least a 50 percent a priori probability.

Measurements of Shock Effects Recorded by Hayabusa Samples

NASA Technical Reports Server (NTRS)

Zolensky, Michael; Mikouchi, Takashi; Hagiya, Kenji; Ohsumi, Kazumasa; Martinez, James; Komatsu, Mutsumi; Chan, Queenie H-.S.

2015-01-01

We requested and have been approved for 5 Hayabusa samples in order definitively establish the degree of shock experienced by the regolith of asteroid Itokawa, and to devise a bridge between shock determinations by standard light optical petrography, crystal structures as determined by synchrotron X-ray diffraction (SXRD), and degree of crystallinity as determined by electron back-scattered diffraction (EBSD) [1,2]. As of the writing of this abstract we are awaiting the approved samples. We propose measurements of astromaterial crystal structures and regolith processes. The proposed research work will improve our understanding of how small, primitive solar system bodies formed and evolved, and improve understanding of the processes that determine the history and future of habitability of environments on other solar system bodies. The results of the proposed research will directly enrich the ongoing asteroid and comet exploration missions by NASA, JAXA and ESA, and broaden our understanding of the origin and evolution of small bodies in the early solar system, and elucidate the nature of asteroid and comet regolith.

Measurements of Shock Effects Recorded by Itokawa Samples

NASA Technical Reports Server (NTRS)

Zolensky, Michael; Mikouchi, Takashi; Hagiya, Kenji; Ohsumi, Kazumasa; Martinez, James; Komatsu, Mutsumi; Chan, Queenie H-.S.

2016-01-01

We requested and have been approved for 5 Hayabusa samples in order definitively establish the degree of shock experienced by the regolith of asteroid Itokawa, and to devise a bridge between shock determinations by standard light optical petrography, crystal structures as determined by synchrotron X-ray diffraction (SXRD), and degree of crystallinity as determined by electron back-scattered diffraction (EBSD). As of the writing of this abstract we are awaiting the approved samples. We propose measurements of astromaterial crystal structures and regolith processes. The proposed research work will improve our understanding of how small, primitive solar system bodies formed and evolved, and improve understanding of the processes that determine the history and future of habitability of environments on other solar system bodies. The results of the proposed research will directly enrich the ongoing asteroid and comet exploration missions by NASA, JAXA and ESA, and broaden our understanding of the origin and evolution of small bodies in the early solar system, and elucidate the nature of asteroid and comet regolith.

Getting Involved with the Discovery Program

NASA Technical Reports Server (NTRS)

Asplund, Shari

2000-01-01

NASA's Discovery Program represents the implementation of NASA Administrator Daniel Goldin's vision of 'faster, better, cheaper' planetary missions; encompasses a series of low-cost solar system exploration missions intended to accomplish high quality, focused planetary science investigations using innovative, streamlined, and efficient approaches to assure the highest science value for the cost; and aims to enhance our understanding of the solar system by exploring the planets, their moons and other small bodies, either by traveling to them or remotely from the vicinity of Earth. The objectives of this program include the following: (1) Provide exciting and important scientific data to the global community; (2) Pursue new and innovative ways of doing business; (3) Encourage technological development by designing and testing new technologies and transferring them to the private sector; (4) Increase public awareness of, and appreciation for, solar system exploration through exciting education and public outreach activities; (5) Support national education initiatives through mission-specific programs; and (6) Ensure participation of small disadvantaged businesses, women-owned businesses, HBCUs, and other minority educational institutions in procurements.

Solar-thermal jet pumping for irrigation

NASA Astrophysics Data System (ADS)

Clements, L. D.; Dellenback, P. A.; Bell, C. A.

1980-01-01

This paper describes a novel concept in solar powered irrigation pumping, gives measured performance data for the pump unit, and projected system performance. The solar-thermal jet pumping concept is centered around a conventional jet eductor pump which is commercially available at low cost. The jet eductor pump is powered by moderate temperature, moderate pressure Refrigerant-113 vapor supplied by a concentrating solar collector field. The R-113 vapor is direct condensed by the produced water and the two fluids are separated at the surface. The water goes on to use and the R-113 is repressurized and returned to the solar field. The key issue in the solar-thermal jet eductor concept is the efficiency of pump operation. Performance data from a small scale experimental unit which utilizes an electrically heated boiler in place of the solar field is presented. The solar-thermal jet eductor concept is compared with other solar irrigation concepts and optimal application situations are identified. Though having lower efficiencies than existing Rankine cycle solar-thermal irrigation systems, the mechanical and operational simplicity of this concept make it competitive with other solar powered irrigation schemes.

Solar Energy Systems for Ohioan Residential Homeowners

NASA Astrophysics Data System (ADS)

Luckett, Rickey D.

Dwindling nonrenewable energy resources and rising energy costs have forced the United States to develop alternative renewable energy sources. The United States' solar energy industry has seen an upsurge in recent years, and photovoltaic holds considerable promise as a renewable energy technology. The purpose of this case study was to explore homeowner's awareness of the benefits of solar energy. Disruptive-innovation theory was used to explore marketing strategies for conveying information to homeowners about access to new solar energy products and services. Twenty residential homeowners were interviewed face-to-face to explore (a) perceived benefits of solar energy in their county in Ohio, and (b) perceptions on the rationale behind the marketing strategy of solar energy systems sold for residential use. The study findings used inductive analyses and coding interpretation to explore the participants' responses that revealed 3 themes: the existence of environmental benefits for using solar energy systems, the expensive cost of equipment associated with government incentives, and the lack of marketing information that is available for consumer use. The implications for positive social change include the potential to enable corporate leaders, small business owners, and entrepreneurs to develop marketing strategies for renewable energy systems. These strategies may promote use of solar energy systems as a clean, renewable, and affordable alternative electricity energy source for the 21st century.

Different parameter and technique affecting the rate of evaporation on active solar still -a review

NASA Astrophysics Data System (ADS)

A, Muthu Manokar; D, Prince Winston; A. E, Kabeel; Sathyamurthy, Ravishankar; T, Arunkumar

2018-03-01

Water is one of the essential sources for the endurance of human on the earth. As earth having only a small amount of water resources for consumption purpose people in rural and urban areas are getting affected by consuming dirty water that leads to water-borne diseases. Even though ground water is available in small quantity, it has to be treated properly before its use for internal consumption. Brackish water contains dissolve and undissolved contents, and hence it is not suitable for the household purpose. Nowadays, distillation process is done by using passive and active solar stills. The major problem in using passive solar still is meeting higher demand for fresh water. The fresh water production from passive solar still is critically low to meet the demand. To improve the productivity of conventional solar still, input feed water is preheated by integrating the solar still to different collector panels. In this review article, the different parameters that affect the rate of evaporation in an active solar still and the different methods incorporated has been presented. In addition to active distillation system, forced convection technique can be incorporated to increase the yield of fresh water by decreasing the temperature of cover. Furthermore, it is identified that the yield of fresh water from the active desalination system can be improved by sensible and latent heat energy storage. This review will motivate the researchers to decide appropriate active solar still technology for promoting development.

The Effect of Tropopause Seeing on Solar Telescope Site Testing

NASA Astrophysics Data System (ADS)

Beckers, Jacques M.

2017-08-01

The site testing for and seeing correction planning of the 4-m solar telescopes has failed to take into account the significant amount of seeing at tropopause levels (10-20 km altitude).The worst aspect of that seeing layer is its small isoplanatic patch size which at low solar elevations can be significantly less than 1 arcsec. The CLEAR/ATST/DKIST SDIMM seeing monitor is insensitive to this type of seeing. A correction for this missed seeing significantly decreases the measured seeing qualities for the sites tested especially in the early morning and late afternoon. It clearly shows the lake site to be superior with mid-day observations much to be preferred. The small tropopause isoplanatic patch size values also complicate the implementation of the solar MCAO systems aimed at large field-of-view sun imaging. Currently planned systems only correct for lower-layer seeing for which the isoplanatic patch size is about one arc minute. To fully achieve the diffraction limit of the 4-meter class (0.025 arcsec at 500 nm), over a large enough field-of-view to be of scientific interest, complicated Multi-Conjugate Adaptive Optics systems will be needed.

Clues in the rare gas isotopes to early solar system history

NASA Technical Reports Server (NTRS)

Reynolds, J. H.

1977-01-01

The results of the radioactive dating and the discovery of gas-rich meteorites on the Moon surface are reviewed. Special attention is paid to the extinct radioactivity iodine-129. This radioactivity is produced by r-process of nucleosynthesis and it decays with a half-life of 17 m.y. It provides a clock sensitive to small changes in the early years of the solar system.

Weak localization of electromagnetic waves and opposition phenomena exhibited by high-albedo atmosphereless solar system objects.

PubMed

Mishchenko, Michael I; Rosenbush, Vera K; Kiselev, Nikolai N

2006-06-20

The totality of new and previous optical observations of a class of high-albedo solar system objects at small phase angles reveals a unique combination of extremely narrow brightness and polarization features centered at exactly the opposition. The specific morphological parameters of these features provide an almost unequivocal evidence that they are caused by the renowned effect of coherent backscattering.

CSP cogeneration of electricity and desalinated water at the Pentakomo field facility

NASA Astrophysics Data System (ADS)

Papanicolas, C. N.; Bonanos, A. M.; Georgiou, M. C.; Guillen, E.; Jarraud, N.; Marakkos, C.; Montenon, A.; Stiliaris, E.; Tsioli, E.; Tzamtzis, G.; Votyakov, E. V.

2016-05-01

The Cyprus Institute's Pentakomo Field Facility (PFF) is a major infrastructure for research, development and testing of technologies relating to concentrated solar power (CSP) and solar seawater desalination. It is located at the south coast of Cyprus near the sea and its environmental conditions are fully monitored. It provides a test facility specializing in the development of CSP systems suitable for island and coastal environments with particular emphasis on small units (<25 MWth) endowed with substantial storage, suitable for use in isolation or distributed in small power grids. The first major experiment to take place at the PFF concerns the development of a pilot/experimental facility for the co-generation of electricity and desalinated seawater from CSP. Specifically, the experimental plant consists of a heliostat-central receiver system for solar harvesting, thermal energy storage in molten salts followed by a Rankine cycle for electricity production and a multiple-effect distillation (MED) unit for desalination.

A small satellite design for deep space network testing and training

NASA Technical Reports Server (NTRS)

Mcwilliams, Dennis; Slatton, Clint; Norman, Cassidy; Araiza, Joe; Jones, Jason; Tedesco, Mark; Wortman, Michael; Opiela, John; Lett, Pat; Clavenna, Michael

1993-01-01

With the continuing exploration of the Solar System and the reemphasis on Earth focused missions, the need for faster data transmission rates has grown. Ka-band could allow a higher data delivery rate over the current X-band, however the adverse effects of the Earth's atmosphere on Ka are as yet unknown. The Deep Space Network and Jet Propulsion Lab have proposed to launch a small satellite that would simultaneously transmit X and Ka signals to test the viability of switching to Ka-band. The Mockingbird Design Team at the University of Texas at Austin applied small satellite design principles to achieve this objective. The Mockingbird design, named BATSAT, incorporates simple, low-cost systems designed for university production and testing. The BATSAT satellite is a 0.64 m diameter, spherical panel led satellite, mounted with solar cells and omni-directional antennae. The antennae configuration negates the need for active attitude control or spin stabilization. The space-frame truss structure was designed for 11 g launch loads while allowing for easy construction and solar-panel mounting. The communication system transmits at 1 mW by carrying the required Ka and X-band transmitters, as well as an S band transmitter used for DSN training. The power system provides the 8.6 W maximum power requirements via silicon solar arrays and nickel-cadmium batteries. The BATSAT satellite will be lofted into an 1163 km, 70 deg orbit by the Pegasus launch system. This orbit fulfills DSN dish slew rate requirements while keeping the satellite out of the heaviest regions of the Van Allen radiation belts. Each of the three DSN stations capable of receiving Ka-band (Goldstone, Canberra, and Madrid) will have an average of 85 minutes of view-time per day over the satellites ten year design life. Mockingbird Designs hopes that its small satellite design will not only be applicable to this specific mission scenario, but that it could easily be modified for instrument capability for university, government, and/or commercial research.

Places Only Sails Can Go

NASA Technical Reports Server (NTRS)

Montgomery, Edward E., IV; Heaton, Andrew F.; Garbe, Gregory P.

2003-01-01

Solar sails are a near term, low thrust, propellantless propulsion technology suitable for orbital maneuvering, station keeping, and attitude control applications for small payloads. Furthermore, these functions can be highly integrated, reducing mass, cost and complexity. The solar sail concept is based on momentum exchange with solar flux reflected from a large, deployed thin membrane. Thrust performance increases as the square of the distance to the sun. In comparison to conventional chemical systems, there are missions where solar sails are vastly more and less economical. The less attractive applications involve large payloads, outer solar system transfers, and short trip times. However, for inclination changes and station keeping at locations requiring constant thrust, the solar sail is the only economical option for missions of more than a few weeks duration. We compare the location and energies required for these applications between solar sails, advanced electric propulsion, and conventional rockets. We address the effect on mass fraction to understand solar sail mission cost and capability. Finally, the benefit of potential applications to near term science missions is reported.

Support System for Solar Receivers

NASA Technical Reports Server (NTRS)

Kiceniuk, T.

1985-01-01

Hinged split-ring mounts insure safe support of heavy receivers. In addition to safer operation and damage-free mounting system provides more accurate focusing, and small incremental adjustments of ring more easily made.

Non-Solar Photovoltaics for Small Space Missions

NASA Technical Reports Server (NTRS)

Landis, Geoffrey A.; Bailey, Sheila G.; Clark, Eric B.; Myers, Matthew G.; Piszazor, Michael F.; Murbach, Marcus S.

2012-01-01

NASA has missions planned to targets in the solar system ranging from the permanently shadowed craters of Mercury to the icy reaches of the Kuiper belt and beyond. In 2011, the NASA Office of the Chief Technologist (OCT) requested the NASA Ames and Glenn Research Centers to assess the potential of small power supplies based on direct conversion of energy from radioisotope sources for future NASA missions; and in particular to assess whether alphavoltaic and betavoltaic power sources could be of potential benefit in small missions, as well as examining the use of miniaturized thermophotovoltaic power supplies. This paper summarizes the results of that assessment.

Microprocessor control of multiple peak power tracking DC/DC converters for use with solar cell arrays

NASA Technical Reports Server (NTRS)

Frederick, Martin E. (Inventor); Jermakian, Joel (Inventor)

1991-01-01

A method and an apparatus is provided for efficiently controlling the power output of a solar cell array string or a plurality of solar cell array strings to achieve a maximum amount of output power from the strings under varying conditions of use. Maximum power output from a solar array string is achieved through control of a pulse width modulated DC/DC buck converter which transfers power from a solar array to a load or battery bus. The input voltage from the solar array to the converter is controlled by a pulse width modulation duty cycle, which in turn is controlled by a differential signal controller. By periodically adjusting the control voltage up or down by a small amount and comparing the power on the load or bus with that generated at different voltage values a maximum power output voltage may be obtained. The system is totally modular and additional solar array strings may be added to the system simply by adding converter boards to the system and changing some constants in the controller's control routines.

Feasibility study of a 110 watt per kilogram lightweight solar array system

NASA Technical Reports Server (NTRS)

Shepard, N. F.; Stahle, C. V.; Schneider, A.; Hanson, K. L.

1972-01-01

An investigation of the feasibility of a solar array panel subsystem which will produce 10,000 watts of electrical output at 1 A.U. with an overall beginning-of-life power-to-weight ratio of at least 110 watt/kg is reported. A description of the current baseline configuration which meets these requirements is presented. A parametric analysis of the single boom, two blanket planar solar array system was performed to arrive at the optimum system aspect ratio. A novel concept for the stiffening of a lightweight solar array by canting the solar cell blankets at a small angle to take advantage of the inherent in-plane stiffness to increase the symmetric out-of-plane frequency is introduced along with a preliminary analysis of the stiffening effect. A comparison of welded and soldered solar cell interconnections leads to the conclusion that welding is required on this ultralightweight solar array. The use of a boron/aluminum composite material in a BI-STEM type deployable boom is investigated as a possible advancement in the state-of-the-art.

Utah | Midmarket Solar Policies in the United States | Solar Research |

Science.gov Websites

Credit: Net excess generation is credited at the retail rate for residential and small commercial customers; large commercial and industrial customers with demand charge may choose between valuing net cost) for residential taxpayers; $50,000 (or 10% of system cost) for commercial taxpayers. Renewable

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.

Goulds Belt, Interstellar Clouds, and the Eocene Oligocene Helium-3 Enhancement

NASA Technical Reports Server (NTRS)

Rubincam, David Parry

2015-01-01

Drag from hydrogen in the interstellar cloud which formed Gould's Belt may have sent interplanetary dust particle (IDPs) and small meteoroids with embedded helium to the Earth, perhaps explaining part the helium-3 flux increase seen in the sedimentary record near the Eocene-Oligocene transition. Assuming the Solar System passed through part of the cloud, IDPs in the inner Solar System may have been dragged to Earth, while dust and small meteoroids in the asteroid belt up to centimeter size may have been dragged to the resonances, where their orbital eccentricities were pumped up into Earth-crossing orbits; however, this hypotheses does not explain the Popigai and Chesapeake Bay impacts.

Meteorites and the Evolution of Our Solar System

NASA Technical Reports Server (NTRS)

Nava, David F.

1999-01-01

The study of meteorites has long been of intense interest ever since these objects were discovered to be of extraterrestrial origin. Meteorite research contributes to unraveling the mysteries in understanding the formation and evolution processes of our solar system. Meteorites, of which there are a variety of widely diverse types of chemical and mineralogical compositions, are the most ancient of solar system objects that can be studied in the laboratory. They preserve a unique historical record of the astronomical and astrophysical events of our solar system. This record is being discerned by a host of ever evolving analytical laboratory methods. Recent discoveries of what are believed to be Martian meteorites, lunar meteorites, a meteorite containing indigenous water, and the recovery from the Cretaceous layer of a small meteorite fragment thought to be from the dinosaur-killing asteroid have fueled additional excitement for studying meteorites.

An interstellar origin for Jupiter's retrograde co-orbital asteroid

NASA Astrophysics Data System (ADS)

Namouni, F.; Morais, M. H. M.

2018-06-01

Asteroid (514107) 2015 BZ509 was discovered recently in Jupiter's co-orbital region with a retrograde motion around the Sun. The known chaotic dynamics of the outer Solar system have so far precluded the identification of its origin. Here, we perform a high-resolution statistical search for stable orbits and show that asteroid (514107) 2015 BZ509 has been in its current orbital state since the formation of the Solar system. This result indicates that (514107) 2015 BZ509 was captured from the interstellar medium 4.5 billion years in the past as planet formation models cannot produce such a primordial large-inclination orbit with the planets on nearly coplanar orbits interacting with a coplanar debris disc that must produce the low-inclination small-body reservoirs of the Solar system such as the asteroid and Kuiper belts. This result also implies that more extrasolar asteroids are currently present in the Solar system on nearly polar orbits.

Lightweight DC-DC Converter with Partial Power Processing and MPPT for a Solar Powered Aircraft

NASA Astrophysics Data System (ADS)

Diab-Marzouk, Ahmad

A lightweight dc-dc partial power processing converter is demonstrated for solar aerospace applications. A system-level model is conceived to determine conformity to payload and target distance objectives, with the Solarship aircraft used as an application example. The concept of partial power processing is utilized to realize a high efficiency lightweight converter that performs Max Peak Power Tracking (MPPT) to transfer power from the aircraft solar array to the high-voltage battery bus. The isolated Cuk is determined to be a suitable converter topology for the application. A small-signal model is derived for control design. The operation of a 400V, 2.7 kW prototype is verified at high frequency (200 kHz), high efficiency (> 98%), small mass (0.604 kg), and uses no electrolytic capacitors. MPPT operation is verified on a 376 V commercial solar installation at The University of Toronto. The prototype serves as an enabling technology for solar aerospace applications.

Prediction of transits of Solar system objects in Kepler/K2 images: an extension of the Virtual Observatory service SkyBoT

NASA Astrophysics Data System (ADS)

Berthier, J.; Carry, B.; Vachier, F.; Eggl, S.; Santerne, A.

2016-05-01

All the fields of the extended space mission Kepler/K2 are located within the ecliptic. Many Solar system objects thus cross the K2 stellar masks on a regular basis. We aim at providing to the entire community a simple tool to search and identify Solar system objects serendipitously observed by Kepler. The sky body tracker (SkyBoT) service hosted at Institut de mécanique céleste et de calcul des éphémérides provides a Virtual Observatory compliant cone search that lists all Solar system objects present within a field of view at a given epoch. To generate such a list in a timely manner, ephemerides are pre-computed, updated weekly, and stored in a relational data base to ensure a fast access. The SkyBoT web service can now be used with Kepler. Solar system objects within a small (few arcminutes) field of view are identified and listed in less than 10 s. Generating object data for the entire K2 field of view (14°) takes about a minute. This extension of the SkyBoT service opens new possibilities with respect to mining K2 data for Solar system science, as well as removing Solar system objects from stellar photometric time series.

Selection and Manufacturing of Membrane Materials for Solar Sails

NASA Technical Reports Server (NTRS)

Bryant, Robert G.; Seaman, Shane T.; Wilkie, W. Keats; Miyaucchi, Masahiko; Working, Dennis C.

2013-01-01

Commercial metallized polyimide or polyester films and hand-assembly techniques are acceptable for small solar sail technology demonstrations, although scaling this approach to large sail areas is impractical. Opportunities now exist to use new polymeric materials specifically designed for solar sailing applications, and take advantage of integrated sail manufacturing to enable large-scale solar sail construction. This approach has, in part, been demonstrated on the JAXA IKAROS solar sail demonstrator, and NASA Langley Research Center is now developing capabilities to produce ultrathin membranes for solar sails by integrating resin synthesis with film forming and sail manufacturing processes. This paper will discuss the selection and development of polymer material systems for space, and these new processes for producing ultrathin high-performance solar sail membrane films.

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.

Design approach for solar cell and battery of a persistent solar powered GPS tracker

NASA Astrophysics Data System (ADS)

Sahraei, Nasim; Watson, Sterling M.; Pennes, Anthony; Marius Peters, Ian; Buonassisi, Tonio

2017-08-01

Sensors with wireless communication can be powered by photovoltaic (PV) devices. However, using solar power requires thoughtful design of the power system, as well as a careful management of the power consumption, especially for devices with cellular communication (because of their higher power consumption). A design approach can minimize system size, weight, and/or cost, while maximizing device performance (data transmission rate and persistence). In this contribution, we describe our design approach for a small form-factor, solar-powered GPS tracker with cellular communication. We evaluate the power consumption of the device in different stages of operation. Combining measured power consumption and the calculated energy-yield of a solar cell, we estimate the battery capacity and solar cell area required for 5 years of continuous operation. We evaluate trade-offs between PV and battery size by simulating the battery state of charge. The data show a trade-off between battery capacity and solar-cell area for given target data transmission rate and persistence. We use this analysis to determine the combination of solar panel area and battery capacity for a given application and the data transmission rate that results in minimum cost or total weight of the system.

Solar Hot Water Heater

NASA Technical Reports Server (NTRS)

1978-01-01

The solar panels pictured below, mounted on a Moscow, Idaho home, are part of a domestic hot water heating system capable of providing up to 100 percent of home or small business hot water needs. Produced by Lennox Industries Inc., Marshalltown, Iowa, the panels are commercial versions of a collector co-developed by NASA. In an effort to conserve energy, NASA has installed solar collectors at a number of its own facilities and is conducting research to develop the most efficient systems. Lewis Research Center teamed with Honeywell Inc., Minneapolis, Minnesota to develop the flat plate collector shown. Key to the collector's efficiency is black chrome coating on the plate developed for use on spacecraft solar cells, the coating prevents sun heat from "reradiating," or escaping outward. The design proved the most effective heat absorber among 23 different types of collectors evaluated in a Lewis test program. The Lennox solar domestic hot water heating system has three main components: the array of collectors, a "solar module" (blue unit pictured) and a conventional water heater. A fluid-ethylene glycol and water-is circulated through the collectors to absorb solar heat. The fluid is then piped to a double-walled jacket around a water tank within the solar module.

Holographic Solar Photon Thrusters

NASA Technical Reports Server (NTRS)

Johnson, Les; Matloff, Greg

2006-01-01

A document discusses a proposal to incorporate holographic optical elements into solar photon thrusters (SPTs). First suggested in 1990, SPTs would be systems of multiple reflective, emissive, and absorptive surfaces (solar sails) that would be attached to spacecraft orbiting the Earth to derive small propulsive forces from radiation pressures. An SPT according to the proposal would include, among other things, a main sail. One side of the sail would be highly emissive and would normally face away from the Earth. The other side would be reflective and would be covered by white-light holographic images that would alternately become reflective, transmissive, and absorptive with small changes in the viewing angle. When the spacecraft was at a favorable orbital position, the main sail would be oriented to reflect sunlight in a direction to maximize the solar thrust; when not in a favorable position, the main sail would be oriented to present a substantially absorptive/emissive aspect to minimize the solar drag. By turning the main sail slightly to alternate between the reflective and absorptive/ emissive extremes, one could achieve nearly a doubling or halving of the radiational momentum transfer and, hence, of the solar thrust.

Long-term influence of asteroids on planet longitudes and chaotic dynamics of the solar system

NASA Astrophysics Data System (ADS)

Woillez, E.; Bouchet, F.

2017-11-01

Over timescales much longer than an orbital period, the solar system exhibits large-scale chaotic behavior and can thus be viewed as a stochastic dynamical system. The aim of the present paper is to compare different sources of stochasticity in the solar system. More precisely we studied the importance of the long term influence of asteroids on the chaotic dynamics of the solar system. We show that the effects of asteroids on planets is similar to a white noise process, when those effects are considered on a timescale much larger than the correlation time τϕ ≃ 104 yr of asteroid trajectories. We computed the timescale τe after which the effects of the stochastic evolution of the asteroids lead to a loss of information for the initial conditions of the perturbed Laplace-Lagrange secular dynamics. The order of magnitude of this timescale is precisely determined by theoretical argument, and we find that τe ≃ 104 Myr. Although comparable to the full main-sequence lifetime of the sun, this timescale is considerably longer than the Lyapunov time τI ≃ 10 Myr of the solar system without asteroids. This shows that the external sources of chaos arise as a small perturbation in the stochastic secular behavior of the solar system, rather due to intrinsic chaos.

Heliostat kinematic system calibration using uncalibrated cameras

NASA Astrophysics Data System (ADS)

Burisch, Michael; Gomez, Luis; Olasolo, David; Villasante, Cristobal

2017-06-01

The efficiency of the solar field greatly depends on the ability of the heliostats to precisely reflect solar radiation onto a central receiver. To control the heliostats with such a precision accurate knowledge of the motion of each of them modeled as a kinematic system is required. Determining the parameters of this system for each heliostat by a calibration system is crucial for the efficient operation of the solar field. For small sized heliostats being able to make such a calibration in a fast and automatic manner is imperative as the solar field potentially contain tens or even hundreds of thousands of them. A calibration system which can rapidly recalibrate a whole solar field would also allow reducing costs. Heliostats are generally designed to provide stability over a large period of time. Being able to relax this requirement and compensate any occurring error by adapting parameters in a model, the costs of the heliostat can be reduced. The presented method describes such an automatic calibration system using uncalibrated cameras rigidly attached to each heliostat. The cameras are used to observe targets spread out through the solar field; based on this the kinematic system of the heliostat can be estimated with high precision. A comparison of this approach to similar solutions shows the viability of the proposed solution.

The application of Fourier transform spectroscopy to the remote identification of solids in the solar system

NASA Technical Reports Server (NTRS)

Larson, H. P.; Fink, U.

1977-01-01

The techniques of Fourier transform spectroscopy combined with large aperture telescopes and advances in detector technology now permit infrared (at a wavelength greater than 1 micron) observations of the surfaces of small solar system objects such as asteroids and satellites. The results demonstrate that this activity can produce important new compositional information related to the origin and evolution of the solar system. The detection of water ice in Saturn's rings and on some of the satellites of Jupiter and Saturn confirm expectations that ices are important mineralogical components in the chemistry of the outer solar system. More recent studies of the mineralogical composition of the surfaces of asteroids provide a new observational link to the origin of meteorites and the early thermal history of the solar system. These results have been dependent upon supporting laboratory studies of the spectral behavior of ices and minerals to define the potential, and limitations, of the method. Since many of the astronomical observations have been exploratory in nature, prospects are good that continued refinement of the techniques will lead to additional insights.

Power processing and control requirements of dispersed solar thermal electric generation systems

NASA Technical Reports Server (NTRS)

Das, R. L.

1980-01-01

Power Processing and Control requirements of Dispersed Receiver Solar Thermal Electric Generation Systems are presented. Kinematic Stirling Engines, Brayton Engines and Rankine Engines are considered as prime movers. Various types of generators are considered for ac and dc link generations. It is found that ac-ac Power Conversion is not suitable for implementation at this time. It is also found that ac-dc-ac Power Conversion with a large central inverter is more efficient than ac-dc-ac Power Conversion using small dispersed inverters. Ac-link solar thermal electric plants face potential stability and synchronization problems. Research and development efforts are needed in improving component performance characteristics and generation efficiency to make Solar Thermal Electric Generation economically attractive.

Hypervelocity impacts and magnetization of small bodies in the Solar System

NASA Technical Reports Server (NTRS)

Chen, Guangqing; Ahrens, Thomas J.; Hide, Raymond

1995-01-01

The observed magnetism of asteroids such as Gaspra and Ida (and other small bodies in the solar system including the Moon and meteorites) may have resulted from an impact-induced shock wave producing a thermodynamic state in which iron-nickel alloy, dispersed in a silicate matrix, is driven from the usual low-temperature, low-pressure, alpha, kaemacite, phase to the paramagnetic, epsilon (hcp), phase. The magnetization was acquired upon rarefaction and reentry into the ferromagnetic, alpha, structure. The degree of remagnetization depends on the strength of the ambient field, which may have been associated with a Solar-System-wide magnetic field. A transient field induced by the impact event itself may have resulted in a significant, or possibly, even a dominant contribution, as well. The scaling law of Housen et al. (Housen, K. R., R. M. Schmidt, and K. A. Holsapple 1991) for catastrophic asteroid impact disaggregation imposes a constraint on the degree to which small planetary bodies may be magnetized and yet survive fragmentation by the same event. Our modeling results show it is possible that Ida was magnetized when a large impact fractured a 125 +/- 22-km-radius protoasteroid to form the Koronis family. Similarly, we calculate that Gaspra could be a magnetized fragment of a 45 +/- 15 km-radius protoasteroid.

Optimization study of small-scale solar membrane distillation desalination systems (s-SMDDS).

PubMed

Chang, Hsuan; Chang, Cheng-Liang; Hung, Chen-Yu; Cheng, Tung-Wen; Ho, Chii-Dong

2014-11-24

Membrane distillation (MD), which can utilize low-grade thermal energy, has been extensively studied for desalination. By incorporating solar thermal energy, the solar membrane distillation desalination system (SMDDS) is a potential technology for resolving energy and water resource problems. Small-scale SMDDS (s-SMDDS) is an attractive and viable option for the production of fresh water for small communities in remote arid areas. The minimum cost design and operation of s-SMDDS are determined by a systematic method, which involves a pseudo-steady-state approach for equipment sizing and dynamic optimization using overall system mathematical models. Two s-SMDDS employing an air gap membrane distillation module with membrane areas of 11.5 m(2) and 23 m(2) are analyzed. The lowest water production costs are $5.92/m(3) and $5.16/m(3) for water production rates of 500 kg/day and 1000 kg/day, respectively. For these two optimal cases, the performance ratios are 0.85 and 0.91; the recovery ratios are 4.07% and 4.57%. The effect of membrane characteristics on the production cost is investigated. For the commercial membrane employed in this study, the increase of the membrane mass transfer coefficient up to two times is beneficial for cost reduction.

Optimization Study of Small-Scale Solar Membrane Distillation Desalination Systems (s-SMDDS)

PubMed Central

Chang, Hsuan; Chang, Cheng-Liang; Hung, Chen-Yu; Cheng, Tung-Wen; Ho, Chii-Dong

2014-01-01

Membrane distillation (MD), which can utilize low-grade thermal energy, has been extensively studied for desalination. By incorporating solar thermal energy, the solar membrane distillation desalination system (SMDDS) is a potential technology for resolving energy and water resource problems. Small-scale SMDDS (s-SMDDS) is an attractive and viable option for the production of fresh water for small communities in remote arid areas. The minimum cost design and operation of s-SMDDS are determined by a systematic method, which involves a pseudo-steady-state approach for equipment sizing and dynamic optimization using overall system mathematical models. Two s-SMDDS employing an air gap membrane distillation module with membrane areas of 11.5 m2 and 23 m2 are analyzed. The lowest water production costs are $5.92/m3 and $5.16/m3 for water production rates of 500 kg/day and 1000 kg/day, respectively. For these two optimal cases, the performance ratios are 0.85 and 0.91; the recovery ratios are 4.07% and 4.57%. The effect of membrane characteristics on the production cost is investigated. For the commercial membrane employed in this study, the increase of the membrane mass transfer coefficient up to two times is beneficial for cost reduction. PMID:25421065

Solar-heating and hot water system--St. Louis, Missouri

NASA Technical Reports Server (NTRS)

1981-01-01

Sunlight supplies about half heat energy needs of small office. System includes six tilt-adjustable commercial collectors and 1,000 gallon energy storage tank. Report contains description of system and components, drawings and photographs, manufacturer's data, and related material.

Pacific Regional Solar Heating Handbook. Second Edition.

ERIC Educational Resources Information Center

Writers' Development Trust, Toronto (Ontario).

This handbook is intended as a guide for engineers, architects, and individuals familiar with heating and ventilating applications who wish to design a solar heating system for a residential or small commercial building in the Pacific Coast Region. The climate of the region is discussed by selected cities in terms of the effect of climate on solar…

Solar Energy system performance evaluation: El Toro, California, March 1981-November 1981

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

Pakkala, P.A.

The El Toro Library is a public library facility in California with an active solar energy system designed to supply 97% of the heating load and 60% of the cooling load. The system is equipped with 1427 square feet of evacuated tube collectors, a 1500-gallon steel storage tank, and an auxiliary natural-gas-fired heating unit. During the period from March 1981 through November 1981 the system supplied only 16% of the space cooling load, far short of the 60% design value. Problems are reported related to control of a valve and of collection, low absorption chiller coefficient of performance during partmore » of the period, and small collector area. Performance data are reported for the system, including solar savings ratio, conventional fuel savings, system performance factor, system coefficient of performance, solar energy utilization, and system operation. Subsystem performance data are also given for the collector, storage, and space cooling subsystems and absorption chiller. The system is briefly described along with performance evaluation techniques and sensors, and typical data are presented for one month. Some weather data are also included. (LEW)« less

Recent work on use of lunar materials for SPS construction

NASA Technical Reports Server (NTRS)

Oneill, G. K.

1980-01-01

The feasibility of mounting a small operation on the Moon to productively use lunar materials in support of programs such as the solar power satellite is addressed. A cost effective scenario of a small chemical process plant on the surface of the Moon and a small machine shop located in orbit is presented. The mass of the space installation is compared to the projected outputs in 90 days. It is indicated that the system would have the capability of replicating about 90% of its own components and would provide the metals, glasses, and silicon needed for the contruction of 90% to 96% of the mass of one solar power satellite per year.

Fast Imaging Solar Spectrograph System in New Solar Telescope

NASA Astrophysics Data System (ADS)

Park, Y.-D.; Kim, Y. H.; Chae, J.; Goode, P. R.; Cho, K. S.; Park, H. M.; Nah, J. K.; Jang, B. H.

2010-12-01

In 2004, Big Bear Solar Observatory in California, USA launched a project for construction of the world's largest aperture solar telescope (D = 1.6m) called New Solar Telescope(NST). University of Hawaii (UH) and Korea Astronomy and Space Science Institute(KASI) partly collaborate on the project. NST is a designed off-axis parabolic Gregorian reflector with very high spatial resolution(0.07 arcsec at 5000A) and is equipped with several scientific instruments such as Visible Imaging Magnetograph (VIM), InfraRed Imaging Magnetograph IRIM), and so on. Since these scientific instruments are focused on studies of the solar photosphere, we need a post-focus instrument for the NST to study the fine structures and dynamic patterns of the solar chromosphere and low Transition Region (TR) layer, including filaments/prominences, spicules, jets, micro flares, etc. For this reason, we developed and installed a fast imaging solar spectrograph(FISS) system on the NST withadvantages of achieving compact design with high spectral resolution and small aberration as well as recording many solar spectral lines in a single and/or dual band mode. FISS was installed in May, 2010 and now we carry out a test observation. In this talk, we introduce the FISS system and the results of the test observation after FISS installation.

Doing more with less - The new way of exploring the solar system

NASA Technical Reports Server (NTRS)

Ridenoure, Rex

1992-01-01

Exploration of the solar system is considered in the light of existing economic factors and scientific priorities, and a general blueprint for an exploration strategy is set forth. Attention is given to mission costs, typical schedules, and the scientific findings of typical projects which create the need for collaboration and diversification in mission development. The combined technologies and cooperative efforts of several small organizations can lead to missions with short schedules and low costs.

Doing more with less - The new way of exploring the solar system

NASA Astrophysics Data System (ADS)

Ridenoure, Rex

1992-08-01

Exploration of the solar system is considered in the light of existing economic factors and scientific priorities, and a general blueprint for an exploration strategy is set forth. Attention is given to mission costs, typical schedules, and the scientific findings of typical projects which create the need for collaboration and diversification in mission development. The combined technologies and cooperative efforts of several small organizations can lead to missions with short schedules and low costs.

Solar system for exploitation of the whole collected energy

NASA Astrophysics Data System (ADS)

Ciamberlini, C.; Francini, F.; Longobardi, G.; Piattelli, M.; Sansoni, P.

2003-09-01

An innovative architecture for the exploitation of the whole collected solar energy is described. A sun pointing optical concentrator focuses the received energy, containing the part of the required solar spectrum, in a low loss optical fibre transmission line. The optical panel is small in size and able to follow the sun in order to collect the maximum of its energy. The support is flat, 5 mm thick and includes four optical concentrators. The efficiency of the optical system depends on the optical configuration and on the material utilised for the optical components. Single commercial connector to the fixed fibres connects the fibre optics' four free ends. The energy is therefore properly transported to any user's end with an easy installation. The system was experimented for lightening, during the day, dissipated in a dark load in order to produce heat in some equipment and for photovoltaic applications. The total efficiency of the system was between 68% and 72%. Once the solar energy reaches the end of the transmission line, it can be addressed to the required utilisation by means of an optical switch, which redirects the sunlight towards the desired applicator. This procedure allows utilising the 100% of the sun-collected energy. Since the size of the panel was small, it can be placed, on the roof, on the garden, on the window-sill, on the field and on all sides exposed to sunlight.

Spacewatch Survey of the Solar System

NASA Technical Reports Server (NTRS)

McMillan, Robert S.

2000-01-01

The purpose of the Spacewatch project is to explore the various populations of small objects throughout the solar system. Statistics on all classes of small bodies are needed to infer their physical and dynamical evolution. More Earth Approachers need to be found to assess the impact hazard. (We have adopted the term "Earth Approacher", EA, to include all those asteroids, nuclei of extinct short period comets, and short period comets that can approach close to Earth. The adjective "near" carries potential confusion, as we have found in communicating with the media, that the objects are always near Earth, following it like a cloud.) Persistent and voluminous accumulation of astrometry of incidentally observed main belt asteroids MBAs will eventually permit the Minor Planet Center (MPQ to determine the orbits of large numbers (tens of thousands) of asteroids. Such a large body of information will ultimately allow better resolution of orbit classes and the determinations of luminosity functions of the various classes, Comet and asteroid recoveries are essential services to planetary astronomy. Statistics of objects in the outer solar system (Centaurs, scattered-disk objects, and Trans-Neptunian Objects; TNOs) ultimately will tell part of the story of solar system evolution. Spacewatch led the development of sky surveying by electronic means and has acted as a responsible interface to the media and general public on this discipline and on the issue of the hazard from impacts by asteroids and comets.

Time-Resolved Records of Magnetic Activity on the Pallasite Parent Body and Psyche

NASA Astrophysics Data System (ADS)

Bryson, J. F. J.; Nichols, C. I. O.; Herrero-Albillos, J.; Kronast, F.; Kasama, T.; Alimadadi, H.; van der Laan, G.; Nimmo, F.; Harrison, R. J.

2014-12-01

Although many small bodies apparently generated dynamo fields in the early solar system, the nature and temporal evolution of these fields has remained enigmatic. Time-resolved records of the Earth's planetary field have been essential in understanding the dynamic history of our planet, and equivalent information from asteroids could provide a unique insight into the development of the solar system. Here we present time-resolved records of magnetic activity on the main-group pallasite parent body and (16) Psyche, obtained using newly-developed nanomagnetic imaging techniques. For the pallasite parent body, the inferred field direction remained relatively constant and the intensity was initially stable at ~100 μT before it decreased in two discrete steps down to 0 μT. We interpret this behaviour as due to vigorous dynamo activity driven by compositional convection in the core, ultimately transitioning from a dipolar to multipolar field as the inner core grew from the bottom-up. For Psyche (measured from IVA iron meteorites), the inferred field direction reversed, while the intensity remained stable at >50 μT. Psyche cooled rapidly as an unmantled core, although the resulting thermal convection alone cannot explain these observations. Instead, this behaviour required top-down core solidification, and is attributed either to compositional convection (if the core also solidified from the bottom-up) or convection generated directly by top-down solidification (e.g. Fe-snow). The mechanism governing convection in small body cores is an open question (due partly to uncertainties in the direction of core solidification), and these observations suggest that unconventional (i.e. not thermal) mechanisms acted in the early solar system. These mechanisms are very efficient at generating convection, implying a long-lasting and widespread epoch of dynamo activity among small bodies in the early solar system.

Evaluating a Small Structural Insulated Panel (SIP) Designed Solar Kiln in Southwestern New Mexico - Part 1

Treesearch

Richard D. Bergman; Ted E.M. Bilek

2012-01-01

With increasing energy costs, using small dry kilns for drying lumber for small-volume value-added wood products has become more of an option when compared with conventional drying. Small solar kilns are one such option, and a number of solar kiln designs exist and are in use. However, questions remain about the design and operation of solar kilns, particularly during...

Long-Term Dynamics of Small Bodies in the Solar System

NASA Technical Reports Server (NTRS)

Holman, Matthew J.

2004-01-01

As part of the NASA Planetary Geology and Geophysics program Prof. Norm Murray (CITA) and I have been conducting investigations of the long-term dynamics of small bodies in the outer solar system. This grant, and its predecessor NAG5- 7761, supports travel for collaboration by the Investigators and also supports Murray during an annual one month visit to the CfA for further collaboration. In the course of this grant we made a number of advances in solar system dynamics. For example, we developed an analytic model for the origin and consequence of chaos associated with three-body resonances in the asteroid belt. This has been shown to be important for the delivery of near Earth objects. We later extended this model to three- body resonances among planets. We were able to show that the numerically identified chaos among the outer planets results from a three-body resonance involving Jupiter, Saturn, and Uranus. The resulting paper was awarded the 1999 Newcomb Cleveland award from the AAAS. This award singles out one paper published in Science each year for distinction.

Origin of the terrestrial planets and the moon.

PubMed

Taylor, S R

1996-03-01

Our ideas about the origin and evolution of the solar system have advanced significantly as a result of the past 25 years of space exploration. Metal-sulfide-silicate partitioning seems to have been present in the early dust components of the solar nebula, prior to chondrule formation. The inner solar nebula was depleted in volatile elements by early solar activity. The early formation of the gas giant, Jupiter, affected the subsequent development of inner solar system and is responsible for the existence of the asteroid belt, and the small size of Mars. The Earth and the other terrestrial planets accreted in a gas-free environment, mostly from volatile-depleted planetesimals which were already differentiated into metallic cores and silicate mantles. The origin of the Moon by a single massive impact with a body larger than Mars explains the angular momentum, orbital characteristics and unique nature of the Earth-Moon system. The density and chemical differences between the Earth and Moon are accounted for by deriving the Moon from the mantle of the impactor.

High efficiency solar cells for concentrator systems: silicon or multi-junction?

NASA Astrophysics Data System (ADS)

Slade, Alexander; Stone, Kenneth W.; Gordon, Robert; Garboushian, Vahan

2005-08-01

Amonix has become the first company to begin production of high concentration silicon solar cells where volumes are over 10 MW/year. Higher volumes are available due to the method of manufacture; Amonix solely uses semiconductor foundries for solar cell production. In the previous years of system and cell field testing, this method of manufacturing enabled Amonix to maintain a very low overhead while incurring a high cost for the solar cell. However, recent simplifications to the solar cell processing sequence resulted in cost reduction and increased yield. This new process has been tested by producing small qualities in very short time periods, enabling a simulation of high volume production. Results have included over 90% wafer yield, up to 100% die yield and world record performance (η =27.3%). This reduction in silicon solar cell cost has increased the required efficiency for multi-junction concentrator solar cells to be competitive / advantageous. Concentrator systems are emerging as a low-cost, high volume option for solar-generated electricity due to the very high utilization of the solar cell, leading to a much lower $/Watt cost of a photovoltaic system. Parallel to this is the onset of alternative solar cell technologies, such as the very high efficiency multi-junction solar cells developed at NREL over the last two decades. The relatively high cost of these type of solar cells has relegated their use to non-terrestrial applications. However, recent advancements in both multi-junction concentrator cell efficiency and their stability under high flux densities has made their large-scale terrestrial deployment significantly more viable. This paper presents Amonix's experience and testing results of both high-efficiency silicon rear-junction solar cells and multi-junction solar cells made for concentrated light operation.

Space Weathering Radiation Environment of the Inner Solar System from the Virtual Energetic Particle Observatory

NASA Astrophysics Data System (ADS)

Cooper, J. F.; Papitashvili, N. E.

2016-12-01

The surfaces of Mercury, the Moon, the moons of Mars, the asteroids, and other small bodies of the inner solar system have been directly weathered for millions to billions of years by solar wind, energetic particle, and solar ultraviolet irradiation. Surface regolith layers to meters in depth are formed by impacts of smaller bodies and micrometeoroids. Sample return missions to small bodies, such as Osiris-REx to the asteroid Bennu, are intended to recover information on the early history of solar system formation, but must contend with the long-term space weathering effects that perturb the original structure and composition of the affected bodies. Solar wind plasma ions at keV energies penetrate only to sub-micron depths, while more energetic solar & heliospheric particles up to MeV energies reach centimeter depths, and higher-energy galactic cosmic rays to GeV energies fully penetrate through the impact regolith. The weathering effects vary with energy and penetration depth from ion implantation and erosive sputtering at solar wind energies to chemical and structural evolution driven by MeV - GeV particles. The energy versus depth dependence of such effects is weighted by the differential flux distributions of the incident particles as measured near the orbits of the affected bodies over long periods of time. Our Virtual Energetic Particle Observatory (http://vepo.gsfc.nasa.gov/) enables simultaneous access to multiple data sets from 1973 through the present in the form of differential flux spectral plots and downloadable data tables. The most continuous VEPO coverage exists for geospace data sources at 1 AU from the Interplanetary Monitoring Platform 8 (IMP-8), launched in 1973, through the present 1-AU constellation including the ACE, WIND, SOHO, and Stereo-A/B spacecraft. Other mission data, e.g. more occasionally from Pioneer-10/11, Helios-1/2, Voyager-1/2, and Ulysses, extend heliospheric coverage from the orbit of Mercury to that of Mars, the asteroid belt, and beyond. Using data from the VEPO services, we show the time-averaged spectra of protons and helium during 1973 - 2016 from Mercury to Mars. The main contributors on solar cycle time scales at keV to MeV energies are large solar flare and ICME events. These time-averaged spectra can then be used for space weathering models of the inner solar system.

Physics and chemistry of the solar nebula.

PubMed

Lunine, J I

1997-06-01

The solar system is thought to have begun in a flattened disk of gas and dust referred to traditionally as the solar nebula. Such a construct seems to be a natural product of the collapse of dense parts of giant molecular clouds, the vast star-forming regions that pepper the Milky Way and other galaxies. Gravitational, magnetic and thermal forces within the solar nebula forced a gradual evolution of mass toward the center (where the sun formed) and angular momentum (borne by a small fraction of the mass) toward the outer more distant regions of the disk. This evolution was accompanied by heating and a strong temperature contrast from the hot, inner regions to the cold, more remote parts of the disk. The resulting chemistry in the disk determined the initial distribution of organic matter in the planets; most of the reduced carbon species, in condensed form, were located beyond the asteroid belt (the 'outer' solar system). The Earth could have received much of its inventory of pre-biological material from comets and other icy fragments of the process of planetary formation in the outer solar system.

The application of simulation modeling to the cost and performance ranking of solar thermal power plants

NASA Technical Reports Server (NTRS)

Rosenberg, L. S.; Revere, W. R.; Selcuk, M. K.

1981-01-01

Small solar thermal power systems (up to 10 MWe in size) were tested. The solar thermal power plant ranking study was performed to aid in experiment activity and support decisions for the selection of the most appropriate technological approach. The cost and performance were determined for insolation conditions by utilizing the Solar Energy Simulation computer code (SESII). This model optimizes the size of the collector field and energy storage subsystem for given engine generator and energy transport characteristics. The development of the simulation tool, its operation, and the results achieved from the analysis are discussed.

A Small Particle Solar Receiver for High Temperature Brayton Power Cycles

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

Miller, Fletcher John

The objective of this project is to design, construct, and test at the Sandia NSTTF a revolutionary high temperature air-cooled solar receiver in the multi-MW range that can be used to drive a gas turbine, to generate low-cost electricity at $.06/kWh when considered as part of an optimized CSP combined cycle system. The receiver being developed in this research uses a dilute suspension of selectively absorbing carbon nano-particles to absorb highly concentrated solar flux. The concept of a volumetric, selective, and continually replenishable absorber is unique in the solar field.

Recent Progress in Heliogyro Solar Sail Structural Dynamics

NASA Technical Reports Server (NTRS)

Wilkie, William K.; Warren, Jerry E.; Horta, Lucas G.; Juang, Jer-Nan; Gibbs, Samuel C.; Dowell, E.; Guerrant, Daniel; Lawrence Dale

2014-01-01

Results from recent National Aeronautics and Space Administration (NASA) research on the structural dynamics and control characteristics of heliogyro solar sails are summarized. Specific areas under investigation include coupled nonlinear finite element analysis of heliogyro membrane blade with solar radiation pressure effects, system identification of spinning membrane structures, solarelastic stability analysis of heliogyro solar sails, including stability during blade deployment, and results from small-scale in vacuo dynamics experiments with spinning high-aspect ratio membranes. A low-cost, rideshare payload heliogyro technology demonstration mission concept, used as a mission context for these heliogyro structural dynamics and solarelasticity investigations, is also described.

Thermal power systems small power systems applications project. Decision analysis for evaluating and ranking small solar thermal power system technologies. Volume 1: A brief introduction to multiattribute decision analysis. [explanation of multiattribute decision analysis methods used in evaluating alternatives for small powered systems

NASA Technical Reports Server (NTRS)

Feinberg, A.; Miles, R. F., Jr.

1978-01-01

The principal concepts of the Keeney and Raiffa approach to multiattribute decision analysis are described. Topics discussed include the concepts of decision alternatives, outcomes, objectives, attributes and their states, attribute utility functions, and the necessary independence properties for the attribute states to be aggregated into a numerical representation of the preferences of the decision maker for the outcomes and decision alternatives.

DEVELOP A CONCENTRATED SOLAR POWER-BASED THERMAL COOLING SYSTEM VIA SIMULATION AND EXPERIMENTAL STUDIES

EPA Science Inventory

A small scale CSP-based cooling system prototype (300W cooling capacity) and the system performance simulation tool will be developed as a proof of concept. Practical issues will be identified to improve our design.

AGUACLARA: CLEAN WATER FOR SMALL COMMUNITIES

EPA Science Inventory

We will systematically evaluate commercially available solar thermal collectors and thermal storage systems for use in residential scale co-generative heat and electrical power systems. Currently, reliable data is unavailable over the range of conditions and installations thes...

Thermo-Magneto-Electric Generator Arrays for Active Heat Recovery System

PubMed Central

Chun, Jinsung; Song, Hyun-Cheol; Kang, Min-Gyu; Kang, Han Byul; Kishore, Ravi Anant; Priya, Shashank

2017-01-01

Continued emphasis on development of thermal cooling systems is being placed that can cycle low grade heat. Examples include solar powered unmanned aerial vehicles (UAVs) and data storage servers. The power efficiency of solar module degrades at elevated temperature, thereby, necessitating the need for heat extraction system. Similarly, data centres in wireless computing system are facing increasing efficiency challenges due to high power consumption associated with managing the waste heat. We provide breakthrough in addressing these problems by developing thermo-magneto-electric generator (TMEG) arrays, composed of soft magnet and piezoelectric polyvinylidene difluoride (PVDF) cantilever. TMEG can serve dual role of extracting the waste heat and converting it into useable electricity. Near room temperature second-order magnetic phase transition in soft magnetic material, gadolinium, was employed to obtain mechanical vibrations on the PVDF cantilever under small thermal gradient. TMEGs were shown to achieve high vibration frequency at small temperature gradients, thereby, demonstrating effective heat transfer. PMID:28145516

Thermo-Magneto-Electric Generator Arrays for Active Heat Recovery System.

PubMed

Chun, Jinsung; Song, Hyun-Cheol; Kang, Min-Gyu; Kang, Han Byul; Kishore, Ravi Anant; Priya, Shashank

2017-02-01

Continued emphasis on development of thermal cooling systems is being placed that can cycle low grade heat. Examples include solar powered unmanned aerial vehicles (UAVs) and data storage servers. The power efficiency of solar module degrades at elevated temperature, thereby, necessitating the need for heat extraction system. Similarly, data centres in wireless computing system are facing increasing efficiency challenges due to high power consumption associated with managing the waste heat. We provide breakthrough in addressing these problems by developing thermo-magneto-electric generator (TMEG) arrays, composed of soft magnet and piezoelectric polyvinylidene difluoride (PVDF) cantilever. TMEG can serve dual role of extracting the waste heat and converting it into useable electricity. Near room temperature second-order magnetic phase transition in soft magnetic material, gadolinium, was employed to obtain mechanical vibrations on the PVDF cantilever under small thermal gradient. TMEGs were shown to achieve high vibration frequency at small temperature gradients, thereby, demonstrating effective heat transfer.

Kuiper Belt Dust Grains as a Source of Interplanetary Dust Particles

NASA Technical Reports Server (NTRS)

Liou, Jer-Chyi; Zook, Herbert A.; Dermott, Stanley F.

1996-01-01

The recent discovery of the so-called Kuiper belt objects has prompted the idea that these objects produce dust grains that may contribute significantly to the interplanetary dust population. In this paper, the orbital evolution of dust grains, of diameters 1 to 9 microns, that originate in the region of the Kuiper belt is studied by means of direct numerical integration. Gravitational forces of the Sun and planets, solar radiation pressure, as well as Poynting-Robertson drag and solar wind drag are included. The interactions between charged dust grains and solar magnetic field are not considered in the model. Because of the effects of drag forces, small dust grains will spiral toward the Sun once they are released from their large parent bodies. This motion leads dust grains to pass by planets as well as encounter numerous mean motion resonances associated with planets. Our results show that about 80% of the Kuiper belt grains are ejected from the Solar System by the giant planets, while the remaining 20% of the grains evolve all the way to the Sun. Surprisingly, the latter dust grains have small orbital eccentricities and inclinations when they cross the orbit of the Earth. This makes them behave more like asteroidal than cometary-type dust particles. This also enhances their chances of being captured by the Earth and makes them a possible source of the collected interplanetary dust particles; in particular, they represent a possible source that brings primitive/organic materials from the outer Solar System to the Earth. When collisions with interstellar dust grains are considered, however, Kuiper belt dust grains around 9 microns appear likely to be collisionally shattered before they can evolve toward the inner part of the Solar System. The collision destruction can be applied to Kuiper belt grains up to about 50 microns. Therefore, Kuiper belt dust grains within this range may not be a significant part of the interplanetary dust complex in the inner Solar System.

Evaluation of Installed Solar Systems at Navy, Army and Air Force Bases.

DTIC Science & Technology

1986-05-01

8217 heVAting, space cooling, and domeistic hot \\\\.0tr I\\ Ntti lit t h \\ s it’ T all ill si/c tlitm smAll t\\%,t) collectr systems to large arra .\\i inti...sites and project personnel. NCEL project personnel were present at most but not all Navy evaluations. The purpose of the evaluations is to gain insight...of solar systems as well as to help develop preventive maintenance programs. The onsite inspections performed by LANL for the Navy and the other

Mars’ Growth Stunted by an Early Giant Planet Instability

NASA Astrophysics Data System (ADS)

Clement, Matthew; Kaib, Nathan A.; Raymond, Sean N.; Walsh, Kevin J.

2017-10-01

Many dynamical aspects of the solar system can be explained by the outer planets experiencing a period of orbital instability. Though often correlated with a perceived delayed spike in the lunar cratering record known as the Late Heavy Bombardment (LHB), recent work suggests that this event may have occurred during the epoch of terrestrial planet formation. Though current simulations of terrestrial accretion can reproduce many observed qualities of the solar system, replicating the small mass of Mars requires modification to standard planet formation models. Here we use direct numerical simulations to show that an early instability in the outer solar system regularly yields properly sized Mars analogues. In 80% of simulations, we produce a Mars of the appropriate mass. Our most successful outcomes occur when the terrestrial planets evolve 10 million years (Myr), and accrete several Mars sized embryos in the Mars forming region before the instability takes place. Mars is left behind as a stranded embryo, while the remainder of these bodies are either ejected from the system or scattered towards the inner solar system where they deliver water to Earth. An early giant planet instability can thus replicate both the inner and outer solar system in a single model.

Studies of new media radiation induced laser

NASA Technical Reports Server (NTRS)

Han, K. S.; Shiu, Y. J.; Raju, S. R.; Hwang, I. H.; Tabibi, B.

1984-01-01

Various lasants were investigated especially, 2-iodohepafluoropropane (i-C3F7I) for the direct solar pumped lasers. Optical pumping of iodine laser was achieved using a small flashlamp. Using i-C3F7I as a laser gain medium, threshold inversion density, small signal gain, and laser performance at the elevated temperature were measured. The experimental results and analysis are presented. The iodine laser kinetics of the C3F7I and IBr system were numerically simulated. The concept of a direct solar-pumped laser amplifier using (i-C3F7I) as the laser material was evaluated and several kinetic coefficients for i-C3F7I laser system were reexamined. The results are discussed.

Advanced turbine systems program conceptual design and product development. Task 3 -- System selection; Topical report

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

White, D.J.

1994-07-01

Solar Turbines Incorporated has elected to pursue an intercooled and recuperated (ICR) gas turbine system to exceed the goals of the DOE Advanced Turbine Systems (ATS) program, which are to develop and commercialize an industrial gas turbine system that operates at thermal efficiencies at least 15% higher than 1991 products, and with emissions not exceeding eight ppmv NOx and 20 ppmv CO and UHC. Solar`s goal is to develop a commercially viable industrial system (3--20 MW) driven by a gas turbine engine with a thermal efficiency of 50% (ATS50), with the flexibility to meet the differing operational requirements of variousmore » markets. Dispersed power generation is currently considered to be the primary future target market for the ICR in the 5--15 MW size class. The ICR integrated system approach provides an ideal candidate for the assumed dispersed power market, with its small footprint, easy transportability, and environmental friendliness. In comparison with other systems that use water or toxic chemicals such as ammonia for NOx control, the ICR has no consumables other than fuel and air. The low pressure ratio of the gas turbine engine also is favorable in that less parasitic power is needed to pump the natural gas into the combustor than for simple-cycle machines. Solar has narrowed the ICR configuration to two basic approaches, a 1-spool, and a 2-spool version of the ATS50. The 1-spool engine will have a lower first-cost but lower part-power efficiencies. The 2-spool ATS may not only have better part-power efficiency, its efficiency will also be less sensitive to reduced turbine rotor inlet temperature levels. Thus hot-end parts life can be increased with only small sacrifices in efficiency. The flexibility of the 2-spool arrangement in meeting customer needs is its major advantage over the 1-spool. This Task 3 Topical Report is intended to present Solar`s preliminary system selection based upon the initial trade-off studies performed to date.« less

RADIOISOTOPE-DRIVEN DUAL-MODE PROPULSION SYSTEM FOR CUBESAT-SCALE PAYLOADS TO THE OUTER PLANETS

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

N. D. Jerred; T. M. Howe; S. D. Howe

It is apparent the cost of planetary exploration is rising as mission budgets declining. Currently small scientific beds geared to performing limited tasks are being developed and launched into low earth orbit (LEO) in the form of small-scale satellite units, i.e., CubeSats. These micro- and nano-satellites are gaining popularity among the university and science communities due to their relatively low cost and design flexibility. To date these small units have been limited to performing tasks in LEO utilizing solar-based power. If a reasonable propulsion system could be developed, these CubeSat platforms could perform exploration of various extra-terrestrial bodies within themore » solar system engaging a broader range of researchers. Additionally, being mindful of mass, smaller cheaper launch vehicles (approximately 1,000 kgs to LEO) can be targeted. Thus, in effect, allows for beneficial exploration to be conducted within limited budgets. Researchers at the Center for Space Nuclear Research (CSNR) are proposing a low mass, radioisotope-based, dual-mode propulsion system capable of extending the exploration realm of these CubeSats out of LEO.« less

Adaptive Optics Imaging of Solar System Objects

NASA Technical Reports Server (NTRS)

Roddier, Francois; Owen, Toby

1999-01-01

Most solar system objects have never been observed at wavelengths longer than the R band with an angular resolution better than 1". The Hubble Space Telescope itself has only recently been equipped to observe in the infrared. However, because of its small diameter, the angular resolution is lower than that one can now achieved from the ground with adaptive optics, and time allocated to planetary science is limited. We have successfully used adaptive optics on a 4-m class telescope to obtain 0.1" resolution images of solar system objects in the far red and near infrared (0.7-2.5 microns), aE wavelengths which best discl"lmlnate their spectral signatures. Our efforts have been put into areas of research for which high angular resolution is essential.

Our Solar System Features Eight Planets

NASA Technical Reports Server (NTRS)

2009-01-01

Our solar system features eight planets, seen in this artist's diagram. Although there is some debate within the science community as to whether Pluto should be classified as a Planet or a dwarf planet, the International Astronomical Union has decided on the term plutoid as a name for dwarf planets like Pluto.

This representation is intentionally fanciful, as the planets are depicted far closer together than they really are. Similarly, the bodies' relative sizes are inaccurate. This is done for the purpose of being able to depict the solar system and still represent the bodies with some detail. (Otherwise the Sun would be a mere speck, and the planets even the majestic Jupiter would be far too small to be seen.)

Energy harvesting concepts for small electric unmanned systems

NASA Astrophysics Data System (ADS)

Qidwai, Muhammad A.; Thomas, James P.; Kellogg, James C.; Baucom, Jared N.

2004-07-01

In this study, we identify and survey energy harvesting technologies for small electrically powered unmanned systems designed for long-term (>1 day) time-on-station missions. An environmental energy harvesting scheme will provide long-term, energy additions to the on-board energy source. We have identified four technologies that cover a broad array of available energy sources: solar, kinetic (wind) flow, autophagous structure-power (both combustible and metal air-battery systems) and electromagnetic (EM) energy scavenging. We present existing conceptual designs, critical system components, performance, constraints and state-of-readiness for each technology. We have concluded that the solar and autophagous technologies are relatively matured for small-scale applications and are capable of moderate power output levels (>1 W). We have identified key components and possible multifunctionalities in each technology. The kinetic flow and EM energy scavenging technologies will require more in-depth study before they can be considered for implementation. We have also realized that all of the harvesting systems require design and integration of various electrical, mechanical and chemical components, which will require modeling and optimization using hybrid mechatronics-circuit simulation tools. This study provides a starting point for detailed investigation into the proposed technologies for unmanned system applications under current development.

Status of Solar Sail Technology Within NASA

NASA Technical Reports Server (NTRS)

Johnson, Les; Young, Roy; Montgomery, Edward; Alhorn, Dean

2010-01-01

In the early 2000s, NASA made substantial progress in the development of solar sail propulsion systems for use in robotic science and exploration of the solar system. Two different 20-m solar sail systems were produced and they successfully completed functional vacuum testing in NASA Glenn Research Center's (GRC's) Space Power Facility at Plum Brook Station, Ohio. The sails were designed and developed by ATK Space Systems and L Garde, respectively. The sail systems consist of a central structure with four deployable booms that support the sails. These sail designs are robust enough for deployment in a one-atmosphere, one-gravity environment and were scalable to much larger solar sails perhaps as large as 150 m on a side. Computation modeling and analytical simulations were also performed to assess the scalability of the technology to the large sizes required to implement the first generation of missions using solar sails. Life and space environmental effects testing of sail and component materials were also conducted. NASA terminated funding for solar sails and other advanced space propulsion technologies shortly after these ground demonstrations were completed. In order to capitalize on the $30M investment made in solar sail technology to that point, NASA Marshall Space Flight Center (MSFC) funded the NanoSail-D, a subscale solar sail system designed for possible small spacecraft applications. The NanoSail-D mission flew on board the ill-fated Falcon-1 Rocket launched August 2, 2008, and due to the failure of that rocket, never achieved orbit. The NanoSail-D flight spare will be flown in the Fall of 2010. This paper will summarize NASA's investment in solar sail technology to-date and discuss future opportunities

Status of solar sail technology within NASA

NASA Astrophysics Data System (ADS)

Johnson, Les; Young, Roy; Montgomery, Edward; Alhorn, Dean

2011-12-01

In the early 2000s, NASA made substantial progress in the development of solar sail propulsion systems for use in robotic science and exploration of the solar system. Two different 20-m solar sail systems were produced. NASA has successfully completed functional vacuum testing in their Glenn Research Center's Space Power Facility at Plum Brook Station, Ohio. The sails were designed and developed by Alliant Techsystems Space Systems and L'Garde, respectively. The sail systems consist of a central structure with four deployable booms that support each sail. These sail designs are robust enough for deployment in a one-atmosphere, one-gravity environment and are scalable to much larger solar sails - perhaps as large as 150 m on a side. Computation modeling and analytical simulations were performed in order to assess the scalability of the technology to the larger sizes that are required to implement the first generation of missions using solar sails. Furthermore, life and space environmental effects testing of sail and component materials was also conducted.NASA terminated funding for solar sails and other advanced space propulsion technologies shortly after these ground demonstrations were completed. In order to capitalize on the $30 M investment made in solar sail technology to that point, NASA Marshall Space Flight Center funded the NanoSail-D, a subscale solar sail system designed for possible small spacecraft applications. The NanoSail-D mission flew on board a Falcon-1 rocket, launched August 2, 2008. As a result of the failure of that rocket, the NanoSail-D was never successfully given the opportunity to achieve orbit. The NanoSail-D flight spare was flown in the Fall of 2010. This review paper summarizes NASA's investment in solar sail technology to date and discusses future opportunities.

Theoretical studies of volatile processes in the outer solar system

NASA Technical Reports Server (NTRS)

Lunine, Jonathan I.

1991-01-01

Four studies of volatile processes in the outer solar system are discussed. Researchers suggest that the convective and conductive regions of Triton's atmosphere join at the tropopause near 10 km. A model of volatile transport on Triton's surface was constructed that predicts that Triton's surface north of 15 degrees north latitude is experiencing deposition of nitrogen frosts, as are the bright portions of the south polar cap near the equator. Also discussed are numerical models of the evolution of Titan's surface and atmosphere. Results of a study of the rheology of ammonia-water liquids were applied to the icy satellites of the outer solar system. Finally, the researchers examined the frictional heating, sublimation, and re-condensation of grains free-falling into the solar nebula from a surrounding interstellar cloud. The sublimation model includes the effect of various volatile species and accounts for the poor radiating properties of small grains using Mie theory.

Modeling and Simulation for an 8 kW Three-Phase Grid-Connected Photo-Voltaic Power System

NASA Astrophysics Data System (ADS)

Cen, Zhaohui

2017-09-01

Gird-connected Photo-Voltaic (PV) systems rated as 5-10 kW level have advantages of scalability and energy-saving, so they are very typical for small-scale household solar applications. In this paper, an 8 kW three-phase grid-connected PV system model is proposed and studied. In this high-fidelity model, some basic PV system components such as solar panels, DC-DC converters, DC-AC inverters and three-phase utility grids are mathematically modelled and organized as a complete simulation model. Also, an overall power controller with Maximum Power Point Control (MPPT) is proposed to achieve both high-efficiency for solar energy harvesting and grid-connection stability. Finally, simulation results demonstrate the effectiveness of the PV system model and the proposed controller, and power quality issues are discussed.

Thin concentrator photovoltaic module with micro-solar cells which are mounted by self-align method using surface tension of melted solder

NASA Astrophysics Data System (ADS)

Hayashi, Nobuhiko; Terauchi, Masaharu; Aya, Youichirou; Kanayama, Shutetsu; Nishitani, Hikaru; Nakagawa, Tohru; Takase, Michihiko

2017-09-01

We are developing a thin and lightweight CPV module using small size lens system made from poly methyl methacrylate (PMMA) with a short focal length and micro-solar cells to decrease the transporting and the installing costs of CPV systems. In order to achieve high conversion efficiency in CPV modules using micro-solar cells, the micro-solar cells need to be mounted accurately to the irradiated region of the concentrated sunlight. In this study, we have successfully developed self-align method thanks to the surface tension of the melted solder even utilizing commercially available surface-mounting technology (SMT). Solar cells were self-aligned to the specified positions of the circuit board by this self-align method with accuracy within ±10 µm. We actually fabricated CPV modules using this self-align method and demonstrated high conversion efficiency of our CPV module.

Cost-Effective Icy Bodies Exploration using Small Satellite Missions

NASA Technical Reports Server (NTRS)

Jonsson, Jonas; Mauro, David; Stupl, Jan; Nayak, Michael; Aziz, Jonathan; Cohen, Aaron; Colaprete, Anthony; Dono-Perez, Andres; Frost, Chad; Klamm, Benjamin;

Japanese Exploration to Solar System Small Bodies: Rewriting a Planetary Formation Theory with Astromaterial Connection (Invited)

NASA Astrophysics Data System (ADS)

Yano, H.

2013-12-01

Three decades ago, Japan's deep space exploration started with Sakigake and Suisei, twin flyby probes to P/Halley. Since then, the Solar System small bodies have been one of focused destinations to the Japanese solar system studies even today. Only one year after the Halley armada launch, the very first meeting was held for an asteroid sample return mission at ISAS, which after 25 years, materialized as the successful Earth return of Hayabusa , an engineering verification mission for sample return from surfaces of an NEO for the first time in the history. Launched in 2003 and returned in 2010, Hayabusa became the first to visit a sub-km, rubble-pile potentially hazardous asteroid in near Earth space. Its returned samples solved S-type asteroid - ordinary chondrite paradox by proving space weathering evidences in sub-micron scale. Between the Halley missions and Hayabusa, SOCCER concept by M-V rocket was jointly studied between ISAS and NASA; yet it was not realized due to insufficient delta-V for intact capture by decelerating flyby/encounter velocity to a cometary coma. The SOCCER later became reality as Stardust, NASA Discovery mission for cometary coma dust sample return in1999-2006. Japan has collected the second largest collection of the Antarctic meteorites and micrometeorites of the world and asteromaterial scientists are eager to collaborate with space missions. Also Japan enjoyed a long history of collaborations between professional astronomers and high-end amateur observers in the area of observational studies of asteroids, comets and meteors. Having these academic foundations, Japan has an emphasis on programmatic approach to sample returns of Solar System small bodies in future prospects. The immediate follow-on to Hayabusa is Hayabusa-2 mission to sample return with an artificial impactor from 1999 JU3, a C-type NEO in 2014-2020. Following successful demonstration of deep space solar sail technique by IKAROS in 2010-2013, the solar power sail is a deep space probe with hybrid propulsion of solar photon sail and ion engine system that will enable Japan to reach out deep interplanetary space beyond the main asteroid belt. Since 2002, Japanese scientists and engineers have been investigating the solar power sail mission to Jupiter Trojans and interdisciplinary cruising science, such as infrared observation of zodiacal light due to cosmic dust, which at the same time hit a large cross section of the solar sail membrane dust detector, concentrating inside the main asteroid belt. Now the mission design has extended from cruising and fly-by only to rendezvous and sample return options from Jupiter Trojan asteroids. Major scientific goal of Jupiter Trojan exploration is to constrain its origin between two competing hypothesis such as remnants of building blocks the Jovian system as the classic model and the second generation captured EKBOs as the planetary migration models, in which several theories are in deep discussion. Also important is to better understand mixing process of material and structure of the early Solar System just beyond snow line. The current plan involves its launch and both solar photon and IES accelerations combined with Earth and Jupiter gravity assists in 2020's, detailed rendezvous investigation of a few 10-km sized D-type asteroid among Jupiter Trojans in early 2030's and an optional sample return of its surface materials to the Earth in late 2030's.

Discovery: Near-Earth Asteroid Rendezvous (NEAR)

NASA Technical Reports Server (NTRS)

Veverka, Joseph

1992-01-01

The work carried out under this grant consisted of two parallel studies aimed at defining candidate missions for the initiation of the Discovery Program being considered by NASA's Solar System Exploration Division. The main study considered a Discover-class mission to a Near Earth Asteroid (NEA); the companion study considered a small telescope in Earth-orbit dedicated to ultra violet studies of solar system bodies. The results of these studies are summarized in two reports which are attached (Appendix 1 and Appendix 2).

Measurement and Modeling of Electromagnetic Scattering by Particles and Particle Groups. Chapter 3

NASA Technical Reports Server (NTRS)

Mishchenko, Michael I.

2015-01-01

Small particles forming clouds of interstellar and circumstellar dust, regolith surfaces of many solar system bodies, and cometary atmospheres have a strong and often controlling effect on many ambient physical and chemical processes. Similarly, aerosol and cloud particles exert a strong influence on the regional and global climates of the Earth, other planets of the solar system, and exoplanets. Therefore, detailed and accurate knowledge of physical and chemical characteristics of such particles has the utmost scientific importance.

Dark matter in the outer solar system

NASA Technical Reports Server (NTRS)

Owen, T.; Cruikshank, D.; De Bergh, C.; Geballe, T.

1994-01-01

There are now a large number of small bodies in the outer solar system that are known to be covered with dark material. Attempts to identify that material have been thwarted by the absence of discrete absorption features in the reflection spectra of these planetesimals. An absorption at 2.2 micrometers that appeared to be present in several objects has not been confirmed by new observations. Three absorptions in the spectrum of the unusually red planetesimal 5145 Pholus are well-established, but their identity remains a mystery.

Electrical research on solar cells and photovoltaic materials

NASA Technical Reports Server (NTRS)

Orehotsky, J.

1984-01-01

The flat-plate solar cell array program which increases the service lifetime of the photovoltaic modules used for terrestrial energy applications is discussed. The current-voltage response characteristics of the solar cells encapsulated in the modules degrade with service time and this degradation places a limitation on the useful lifetime of the modules. The most desirable flat-plate array system involves solar cells consisting of highly polarizable materials with similar electrochemical potentials where the cells are encapsulated in polymers in which ionic concentrations and mobilities are negligibly small. Another possible mechanism limiting the service lifetime of the photovoltaic modules is the gradual loss of the electrical insulation characteristics of the polymer pottant due to water absorption or due to polymer degradation from light or heat effects. The mechanical properties of various polymer pottant materials and of electrochemical corrosion mechanisms in solar cell material are as follows: (1) electrical and ionic resistivity; (2) water absorption kinetics and water solubility limits; and (3) corrosion characterization of various metallization systems used in solar cell construction.

Direct solar-pumped iodine laser amplifier

NASA Technical Reports Server (NTRS)

Han, Kwang S.; Hwang, In Heon; Stock, Larry V.

1989-01-01

This semiannual progress report covers the period from September 1, 1988 to February 28, 1989 under NASA grant NAG-1-441 entitled, Direct Solar-Pumped Iodine Laser Amplifier. During this period, the research effort was concentrated on the solar pumped master oscillator power amplifier (MOPA) system using n-C3F7I. In the experimental work, the amplification measurement was conducted to identify the optimum conditions for amplification of the center's Vortek solar simulator pumped iodine laser amplifier. A modeling effort was also pursued to explain the experimental results in the theoretical work. The amplification measurement of the solar simulator pumped iodine laser amplifier is the first amplification experiment on the continuously pumped amplifier. The small signal amplification of 5 was achieved for the triple pass geometry of the 15 cm long solar simulator pumped amplifier at the n-C3F7I pressure of 20 torr, at the flow velocity of 6 m/sec and at the pumping intensity of 1500 solar constants. The XeCl laser pumped iodine laser oscillator, which was developed in the previous research, was employed as the master oscillator for the amplification measurement. In the theoretical work, the rate equations of the amplifier was established and the small signal amplification was calculated for the solar simulator pumped iodine laser amplifier. The amplification calculated from the kinetic equations with the previously measured rate coefficients reveals very large disagreement with experimental measurement. Moreover, the optimum condition predicted by the kinetic equation is quite discrepant with that measured by experiment. This fact indicates the necessity of study in the measurement of rate coefficients of the continuously pumped iodine laser system.

Trojan Tour and Rendezvous (TTR): A New Frontiers Mission to Conduct the First Detailed Reconnaissance of the Jupiter Trojan Asteroids

NASA Astrophysics Data System (ADS)

Bell, James F.; Olkin, Cathy; Castillo-Rogez, Julie

2015-11-01

Among the most potentially diagnostic but least explored populations of small bodies are the Jupiter Trojan asteroids, which orbit at ~5 AU in the L4 and L5 Lagrange points of Jupiter. The Trojans provide a unique perspective on solar system history, because their locations and physical, compositional, and mineralogic properties preserve evidence for important gravitational interactions among the giant planets. The locations and orbital properties of more than 6200 Jupiter Trojans are now known, but that is likely only a small fraction of a population of up to ~1e6 Trojans >1 km in size. The Trojans are hypothesized to be either former KBOs scattered into the inner solar system by early giant planet migration and then trapped in L4 and L5, or bodies formed near 5 AU in a more quiescent early solar system.Important Planetary Decadal Survey questions that can be addressed by studying the Trojans include: (a) How did the giant planets and their satellite systems accrete, and is there evidence that they migrated to new orbital positions? (b) What is the relationship between large and small KBOs? Is the small population derived by impact disruption of the large one? (c) What kinds of surface evolution, radiation chemistry, and surface-atmosphere interactions occur on distant icy primitive bodies? And (d) What are the sources of asteroid groups (Trojans and Centaurs) that remain to be explored by spacecraft?Here we describe the Trojan Tour and Rendezvous (TTR) New Frontiers mission concept, which is designed to answer these Decadal questions and to test hypotheses for early giant planet migration and solar system evolution. Via close flybys of many of these objects, and orbital characterization of at least one large Trojan, TTR will enable the initial up-close exploration of this population. Our primary mission goals are to characterize the overall surface geology, geochemistry and mineralogy of these worlds; to characterize their internal structure and dynamical properties; to investigate the nature, sources and history of activity on these bodies; and to explore the diversity of the broader Trojan asteroid population.

Application of an electrochemical chlorine-generation system combined with solar energy as appropriate technology for water disinfection.

PubMed

Choi, Jusol; Park, Chan Gyu; Yoon, Jeyong

2013-02-01

Affordable water disinfection is key to reducing the waterborne disease experienced worldwide where resources are limited. A simple electrochemical system that can generate chlorine as a disinfectant from the electrolysis of sodium chloride is an appropriate technology to produce clean water, particularly if driven by solar energy. This study examined the affordability of an electrochemical chlorine generation system using solar energy and developed the necessary design information for its implementation. A two-electrode batch reactor, equipped with commercial IrO(2)-coated electrodes and a solar panel (approximate area 0.2 m(2)), was used to produce chlorine from a 35g/L solution of NaCl. Within 1 h, sufficient chlorine (0.8 g) was generated to produce clean drinking water for about 80 people for 1 day (target microorganism: Escherichia coli; daily drinking water requirement: 2 L per person; chlorine demand: 4 mg/L; solar power: 650 W/m(2) in Seoul, Korea. Small household batteries were demonstrated to be a suitable alternative power source when there is insufficient solar irradiation. Using a 1 m(2) solar panel, the reactor would take only 15 min in Seoul, Korea, or 7 min in the tropics (solar power 1300 W/m(2)), to generate 1 g of chlorine. The solar-powered electrochemical chlorine generation system for which design information is provided here is a simple and affordable way to produce chlorine with which to convert contaminated water into clean drinking water.

Performance Comparisons and Down Selection of Small Motors for Two-Blade Heliogyro Solar Sail 6U CubeSat

NASA Technical Reports Server (NTRS)

Wiwattananon, Peerawan; Bryant, Robert G.

2015-01-01

This report compiles a review of 130 commercial small scale motors (piezoelectric and electric motors) and almost 20 researched-type small scale piezoelectricmotors for potential use in a 2 blades Heliogyro Solar Sail 6U CubeSat. In this application, a motor and gearhead (drive system) will deploy a roll of solar sailthin film (2 um thick)accommodated in a 2U CubeSat (100 x 200 x 100 mm) housing. The application requirements are: space rated, output torque at fulldeployment of 0.8 Nm, reel speed of 3 rpm, drive system weight limited to 150 grams, diameter limited to 50 mm, and the length not to exceed 40 mm. The 50mm diameter limit was imposed as motors with larger diameters would likely weigh too much and use more space on the satellite wall. This would limit theamount of the payload. The motors performance are compared between small scale, volume within 3x102 cm3 (3x105 mm3), commercial electric DC motors,commercial piezoelectric motors, and researched-type (non-commercial) piezoelectric motors extracted from scientific and product literature. The comparisonssuggest that piezoelectric motors without a gearhead exhibit larger output torque with respect to their volume and weight and require less input power toproduce high torque. A commercially available electric motor plus a gearhead was chosen through a proposed selection process to meet the applications designrequirements.

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.

Discovering the Solar System

NASA Astrophysics Data System (ADS)

Jones, Barrie W.

1999-04-01

Discovering the Solar System Barrie W. Jones The Open University, Milton Keynes, UK Discovering the Solar System is a comprehensive, up-to-date account of the Solar System and of the ways in which the various bodies have been investigated and modelled. The approach is thematic, with sequences of chapters on the interiors of planetary bodies, on their surfaces, and on their atmospheres. Within each sequence there is a chapter on general principles and processes followed by one or two chapters on specific bodies. There is also an introductory chapter, a chapter on the origin of the Solar System, and a chapter on asteroids, comets and meteorites. Liberally illustrated with diagrams, black and white photographs and colour plates, Discovering the Solar System also features: * tables of essential data * question and answers within the text * end of section review questions with answers and comments Discovering the Solar System is essential reading for all undergraduate students for whom astronomy or planetary science are components of their degrees, and for those at a more advanced level approaching the subject for the first time. It will also be of great interest to non-specialists with a keen interest in astronomy. A small amount of scientific knowledge is assumed plus familiarity with basic algebra and graphs. There is no calculus. Praise for this book includes: ".certainly qualifies as an authoritative text. The author clearly has an encyclopedic knowledge of the subject." Meteorics and Planetary Science ".liberally doused with relevant graphs, tables, and black and white figures of good quality." EOS, Transactions of the American Geophysical Union ".one of the best books on the Solar System I have seen. The general accuracy and quality of the content is excellent." Journal of the British Astronomical Association

A modular electric power system test bed for small spacecraft

NASA Technical Reports Server (NTRS)

Button, Robert M.; Baez, Anastacio N.

1994-01-01

In the new climate of smaller, faster, and cheaper space science satellites, a new power system topology has been developed at the NASA Lewis Research Center. This new topology is based on a series connected boost converter (SCBC) and can greatly affect the size, weight, fault tolerance, and cost of any small spacecraft using photovoltaic solar arrays. The paper presents electric power system design factors and requirements as background information. The series connected boost converter topology is discussed and several advantages over existing technologies are illustrated. Besides being small, lightweight, and efficient, this topology has the added benefit of inherent fault tolerance. A positive ground power system test bed has been developed for the TROPIX spacecraft program. Performance of the SCBC in the test bed is described in detail. SCBC efficiencies of 95 percent to 98 percent have been measured. Finally, a modular, photovoltaic regulator 'kit' concept is presented. Two SCBC's are used to regulate solar array charging of batteries and to provide 'utilitytype' power to the user loads. The kit's modularity will allow a spacecraft electric power system to be built from off-the-shelf hardware; resulting in smaller, faster, and cheaper spacecraft.

Lightweight Innovative Solar Array (LISA): Providing Higher Power to Small Spacecraft

NASA Technical Reports Server (NTRS)

Johnson, Les; Carr, John; Fabisinski, Leo; Russell,Tiffany; Smith, Leigh

2015-01-01

Affordable and convenient access to electrical power is essential for all spacecraft and is a critical design driver for the next generation of smallsats, including cubesats, which are currently extremely power limited. The Lightweight Innovative Solar Array (LISA), a concept designed, prototyped, and tested at the NASA Marshall Space Flight Center (MSFC) in Huntsville, Alabama provides an affordable, lightweight, scalable, and easily manufactured approach for power generation in space. This flexible technology has many wide-ranging applications from serving small satellites to providing abundant power to large spacecraft in GEO and beyond. By using very thin, ultra-flexible solar arrays adhered to an inflatable structure, a large area (and thus large amount of power) can be folded and packaged into a relatively small volume. The LISA array comprises a launch-stowed, orbit-deployed structure on which lightweight photovoltaic devices and, potentially, transceiver elements are embedded. The system will provide a 2.5 to 5 fold increase in specific power generation (Watts/kilogram) coupled with a >2x enhancement of stowed volume (Watts/cubic-meter) and a decrease in cost (dollars/Watt) when compared to state-of-the-art solar arrays.

Extrapolation of space weathering processes to other small solar system bodies

NASA Astrophysics Data System (ADS)

Gaffey, M. J.

A diverse range of processes were invoked as the dominant factor or as important contributory factors in the modification of the optical surface and regolith of the moon. These include impact vitrification by large and small projectiles, solar wind implantation and the reduction of oxidized iron during energetic events, sputtering and crystal lattice damage by energetic cosmic rays, shock metamorphism of minerals, mixing of diverse lithologies by impacts, and contamination by external materials. These processes are also potentially important on the rocky surfaces of other small solar system bodies. For icy bodies, several additional processes are also possible, including formation of complex organic compounds from methane and ammonia-bearing ices by ultraviolet irradiation and the condensation of vapor species to form frost layers in the polar or cooler regions of objects at appropriate heliocentric distances. The lunar case, even when completely understood, will not extend in a simple linear fashion to other small rocky objects, nor will the optical surfaces of those objects all be affected to the same degree by each process. The major factors that will control the relative efficacy of a possible mechanism include the efficiency of ejecta retention and the degree to which the regolith materials experience multiple events (primarily a function of body size, escape velocity, and impactor velocities); the mean duration of typical regolith particle exposure at the optical surface and within reach of the micrometeorite, cosmic ray, solar wind, or UV fluxes (a function of the rate and scale of regolith mixing, production, and removal processes); the incident flux of solar (low energy) cosmic rays, solar wind, or UV radiation (inverse square of heliocentric distance) or of galactic (high energy) cosmic rays (slowly increasing flux with heliocentric distance); and the compositional and mineralogical nature of the surface being affected. In general, those processes that depend upon either the retention of impact ejecta or on the presence of multigenerational regoliths should be substantially less effective on smaller bodies with lower escape velocities. However, there are important exceptions to this generalization. For example, a process that involves the hypervelocity impact of small particles into a fine-grained regolith may be able to effectively retain highly shocked or melted material due to the nature of shock wave propagation in such a heterogeneous material.

Extrapolation of space weathering processes to other small solar system bodies

NASA Technical Reports Server (NTRS)

Gaffey, M. J.

1993-01-01

A diverse range of processes were invoked as the dominant factor or as important contributory factors in the modification of the optical surface and regolith of the moon. These include impact vitrification by large and small projectiles, solar wind implantation and the reduction of oxidized iron during energetic events, sputtering and crystal lattice damage by energetic cosmic rays, shock metamorphism of minerals, mixing of diverse lithologies by impacts, and contamination by external materials. These processes are also potentially important on the rocky surfaces of other small solar system bodies. For icy bodies, several additional processes are also possible, including formation of complex organic compounds from methane and ammonia-bearing ices by ultraviolet irradiation and the condensation of vapor species to form frost layers in the polar or cooler regions of objects at appropriate heliocentric distances. The lunar case, even when completely understood, will not extend in a simple linear fashion to other small rocky objects, nor will the optical surfaces of those objects all be affected to the same degree by each process. The major factors that will control the relative efficacy of a possible mechanism include the efficiency of ejecta retention and the degree to which the regolith materials experience multiple events (primarily a function of body size, escape velocity, and impactor velocities); the mean duration of typical regolith particle exposure at the optical surface and within reach of the micrometeorite, cosmic ray, solar wind, or UV fluxes (a function of the rate and scale of regolith mixing, production, and removal processes); the incident flux of solar (low energy) cosmic rays, solar wind, or UV radiation (inverse square of heliocentric distance) or of galactic (high energy) cosmic rays (slowly increasing flux with heliocentric distance); and the compositional and mineralogical nature of the surface being affected. In general, those processes that depend upon either the retention of impact ejecta or on the presence of multigenerational regoliths should be substantially less effective on smaller bodies with lower escape velocities. However, there are important exceptions to this generalization. For example, a process that involves the hypervelocity impact of small particles into a fine-grained regolith may be able to effectively retain highly shocked or melted material due to the nature of shock wave propagation in such a heterogeneous material.

A-π-D-π-A Electron-Donating Small Molecules for Solution-Processed Organic Solar Cells: A Review.

PubMed

Wang, Zhen; Zhu, Lingyun; Shuai, Zhigang; Wei, Zhixiang

2017-11-01

Organic solar cells based on semiconducting polymers and small molecules have attracted considerable attention in the last two decades. Moreover, the power conversion efficiencies for solution-processed solar cells containing A-π-D-π-A-type small molecules and fullerenes have reached 11%. However, the method for designing high-performance, photovoltaic small molecules still remains unclear. In this review, recent studies on A-π-D-π-A electron-donating small molecules for organic solar cells are introduced. Moreover, the relationships between molecular properties and device performances are summarized, from which inspiration for the future design of high performance organic solar cells may be obtained. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

NASA's Discovery Program: Moving Toward the Edge (of the Solar System)

NASA Technical Reports Server (NTRS)

Johnson, Les; Gilbert, Paul

2007-01-01

NASA's Planetary Science , Division sponsors a competitive program of small spacecraft missions with the goal of performing focused science investigations that complement NASA's larger planetary science explorations at relatively low cost. The goal of the Discovery program is to launch many smaller missions with fast development times to increase our understanding of the solar system by exploring the planets, dwarf planets, their moons, and small bodies such as comets and asteroids. Discovery missions are solicited from the broad planetary science community approximately every 2 years. Active missions within the Discovery program include several with direct scientific or engineering connections to potential future missions to the edge of the solar system and beyond. In addition to those in the Discovery program are the missions of the New Frontiers program. The first New Frontiers mission. is the New Horizons mission to Pluto, which will explore this 38-AU distant dwarf planet and potentially some Kuiper Belt objects beyond. The Discovery program's Dawn mission, when launched in mid-2007, will use ion drive as its primary propulsion system. Ion propulsion is one of only two technologies that appear feasible for early interstellar precursor missions with practical flight times. The Kepler mission will explore the structure and diversity of extrasolar planetary systems, with an emphasis on the detection of Earth-size planets around other stars. Kepler will survey nearby solar systems searching for planets that may fall within the habitable zone,' a region surrounding a star within which liquid water may exist on a planet's surface - an essential ingredient for life as we know it. With its open and competitive approach to mission selections, the Discovery program affords scientists the opportunity to propose missions to virtually any solar system destination. With its emphasis on science and proven openness to the use of new technologies such as ion propulsion, missions flown as part of the program will test out technologies needed for future very deep-space exploration and potentially take us to these difficult and distant destinations.

Solar water heater for NASA's Space Station

NASA Technical Reports Server (NTRS)

Somers, Richard E.; Haynes, R. Daniel

1988-01-01

The feasibility of using a solar water heater for NASA's Space Station is investigated using computer codes developed to model the Space Station configuration, orbit, and heating systems. Numerous orbit variations, system options, and geometries for the collector were analyzed. Results show that a solar water heater, which would provide 100 percent of the design heating load and would not impose a significant impact on the Space Station overall design is feasible. A heat pipe or pumped fluid radial plate collector of about 10-sq m, placed on top of the habitat module was found to be well suited for satisfying water demand of the Space Station. Due to the relatively small area required by a radial plate, a concentrator is unnecessary. The system would use only 7 to 10 percent as much electricity as an electric water-heating system.

Multifunctional Inflatable Structure Being Developed for the PowerSphere Concept

NASA Technical Reports Server (NTRS)

Peterson, Todd T.

2003-01-01

The continuing development of microsatellites and nanosatellites for low Earth orbits requires the collection of sufficient power for instruments onboard a low-weight, low-volume spacecraft. Because the overall surface area of a microsatellite or nanosatellite is small, body-mounted solar cells cannot provide enough power. The deployment of traditional, rigid, solar arrays necessitates larger satellite volumes and weights, and also requires extra apparatus for pointing. One solution to this power choke problem is the deployment of a spherical, inflatable power system. This power system, termed the "PowerSphere," has several advantages, including a high collection area, low weight and stowage volume, and the elimination of solar array pointing mechanisms.

Development of a Solar System Concept Inventory

NASA Astrophysics Data System (ADS)

Hornstein, Seth D.; Duncan, D.; S, C. A. T.

2009-01-01

Concept inventories can provide useful insight into students’ understanding of key physical concepts. Knowing what your students have learned during a course is a valuable tool for improving your own teaching. Unfortunately, current astronomy concept inventories are not suitable for an introductory solar system course because they either cover too broad of a range of topics (e.g. Astronomy Diagnostic Test) or are too narrowly focused (e.g. Greenhouse Effect Concept Inventory, Lunar Phase Concept Inventory). We have developed the Solar System Concept Inventory (SSCI) to cover those topics commonly taught in an introductory solar system course. The topics included on the SSCI were selected by having faculty identify the key concepts they address when teaching about the solar system. SSCI topics include formation mechanisms, planetary interiors, atmospheric effects, and small solar system bodies. Student interviews were conducted to identify common naive ideas and reasoning difficulties relating to these key topics. Preliminary development of the SSCI was completed at the University of Colorado and involved over 400 students. A larger, national, multi-institutional field test is planned for Spring 2009 as a Collaboration of Astronomy Teaching Scholars (CATS) research project. We present here the results from the preliminary development and proposed changes for the next stage of research. We would like to thank the NSF for funding under Grant No. 0715517, a CCLI Phase III Grant for the Collaboration of Astronomy Teaching Scholars (CATS) Program.

Enhancement of the photovoltaic performance in P3HT: PbS hybrid solar cells using small size PbS quantum dots

NASA Astrophysics Data System (ADS)

Firdaus, Yuliar; Vandenplas, Erwin; Justo, Yolanda; Gehlhaar, Robert; Cheyns, David; Hens, Zeger; Van der Auweraer, Mark

2014-09-01

Different approaches of surface modification of the quantum dots (QDs), namely, solution-phase (octylamine, octanethiol) and post-deposition (acetic acid, 1,4-benzenedithiol) ligand exchange were used in the fabrication of hybrid bulk heterojunction solar cell containing poly (3-hexylthiophene) (P3HT) and small (2.4 nm) PbS QDs. We show that replacing oleic acid by shorter chain ligands improves the figures of merit of the solar cells. This can possibly be attributed to a combination of a reduced thickness of the barrier for electron transfer and an optimized phase separation. The best results were obtained for post-deposition ligand exchange by 1,4-benzenedithiol, which improves the power conversion efficiency of solar cells based on a bulk heterojunction of lead sulfide (PbS) QDs and P3HT up to two orders of magnitude over previously reported hybrid cells based on a bulk heterojunction of P3HT:PbS QDs, where the QDs are capped by acetic acid ligands. The optimal performance was obtained for solar cells with 69 wt. % PbS QDs. Besides the ligand effects, the improvement was attributed to the formation of an energetically favorable bulk heterojunction with P3HT, when small size (2.4 nm) PbS QDs were used. Dark current density-voltage (J-V) measurements carried out on the device provided insight into the working mechanism: the comparison between the dark J-V characteristics of the bench mark system P3HT:PCBM and the P3HT:PbS blends allows us to conclude that a larger leakage current and a more efficient recombination are the major factors responsible for the larger losses in the hybrid system.

Modeling the small-scale dish-mounted solar thermal Brayton cycle

NASA Astrophysics Data System (ADS)

Le Roux, Willem G.; Meyer, Josua P.

2016-05-01

The small-scale dish-mounted solar thermal Brayton cycle (STBC) makes use of a sun-tracking dish reflector, solar receiver, recuperator and micro-turbine to generate power in the range of 1-20 kW. The modeling of such a system, using a turbocharger as micro-turbine, is required so that optimisation and further development of an experimental setup can be done. As a validation, an analytical model of the small-scale STBC in Matlab, where the net power output is determined from an exergy analysis, is compared with Flownex, an integrated systems CFD code. A 4.8 m diameter parabolic dish with open-cavity tubular receiver and plate-type counterflow recuperator is considered, based on previous work. A dish optical error of 10 mrad, a tracking error of 1° and a receiver aperture area of 0.25 m × 0.25 m are considered. Since the recuperator operates at a very high average temperature, the recuperator is modeled using an updated ɛ-NTU method which takes heat loss to the environment into consideration. Compressor and turbine maps from standard off-the-shelf Garrett turbochargers are used. The results show that for the calculation of the steady-state temperatures and pressures, there is good comparison between the Matlab and Flownex results (within 8%) except for the recuperator outlet temperature, which is due to the use of different ɛ-NTU methods. With the use of Matlab and Flownex, it is shown that the small-scale open STBC with an existing off-the-shelf turbocharger could generate a positive net power output with solar-to-mechanical efficiency of up to 12%, with much room for improvement.

On-Orbit Demonstration of a Lithium-Ion Capacitor and Thin-Film Multijunction Solar Cells

NASA Astrophysics Data System (ADS)

Kukita, Akio; Takahashi, Masato; Shimazaki, Kazunori; Kobayashi, Yuki; Sakai, Tomohiko; Toyota, Hiroyuki; Takahashi, Yu; Murashima, Mio; Uno, Masatoshi; Imaizumi, Mitsuru

2014-08-01

This paper describes an on-orbit demonstration of the Next-generation Small Satellite Instrument for Electric power systems (NESSIE) on which an aluminum- laminated lithium-ion capacitor (LIC) and a lightweight solar panel called KKM-PNL, which has space solar sheets using thin-film multijunction solar cells, were installed. The flight data examined in this paper covers a period of 143 days from launch. We verified the integrity of an LIC constructed using a simple and lightweight mounting method: no significant capacitance reduction was observed. We also confirmed that inverted metamorphic multijunction triple-junction thin-film solar cells used for evaluation were healthy at 143 days after launch, because their degradation almost matched the degradation predictions for dual-junction thin-film solar cells.

Space weathering and the color indexes of minor bodies in the outer Solar System

NASA Astrophysics Data System (ADS)

Kaňuchová, Zuzana; Brunetto, Rosario; Melita, Mario; Strazzulla, Giovanni

2012-09-01

The surfaces of small bodies in the outer Solar System are rich in organic compounds and carbonaceous refractories mixed with ices and silicates. As made clear by dedicated laboratory experiments space weathering (e.g. energetic ion bombardment) can produce red colored materials starting from bright and spectrally flat ices. In a classical scenario, the space weathering processes “nurture” alter the small bodies surface spectra but are in competition with resurfacing agents that restore the original colors, and the result of these competing processes continuously modifying the surfaces is supposed to be responsible for the observed spectral variety of those small bodies. However an alternative point of view is that the different colors are due to “nature” i.e. to the different primordial composition of different objects. In this paper we present a model, based on laboratory results, that gives an original contribution to the “nature” vs. “nurture” debate by addressing the case of surfaces showing different fractions of rejuvenated vs. space weathered surface, and calculating the corresponding color variations. We will show how a combination of increasing dose coupled to different resurfacing can reproduce the whole range of observations of small outer Solar System bodies. Here we demonstrate, for the first time that objects having a fully weathered material turn back in the color-color diagrams. At the same time, object with the different ratio of pristine and weathered surface areas lay on specific lines in color-color diagrams, if exposed to the same amount of irradiation.

Lightweight Integrated Solar Array and Transceiver. [Improving Electrical Power and Communication Capabilities in Small Spacecraft

NASA Technical Reports Server (NTRS)

Carr, John; Martinez, Andres; Petro, Andrew

2015-01-01

The Lightweight Integrated Solar Array and Transceiver (LISA-T) project will leverage several existing and on-going efforts at Marshall Space Flight Center (MSFC) for the design, development, fabrication, and test of a launch stowed, orbit deployed structure on which thin-film photovoltaics for power generation and antenna elements for communication, are embedded. Photovoltaics is a method for converting solar energy into electricity using semiconductor materials. The system will provide higher power generation with a lower mass, smaller stowage volume, and lower cost than the state of the art solar arrays, while simultaneously enabling deployable antenna concepts.

Spacelab mission 2: Experimental descriptions

NASA Technical Reports Server (NTRS)

Clifton, K. S. (Editor)

1982-01-01

The second Spacelab Mission and the 12 multidisciplinary experiments selected to fly on board are described. These experiments include the following: vitamin D metabolities and bone demineralization; interaction of oxygen and gravity influenced lignification; ejectable plasma diagnostics package; plasma depletion experiments for ionospheric and radio astronomical studies; small helium cooled IR telescope; elemental composition and energy spectra of cosmic ray nuclei; hard X-ray imaging of clusters of galaxies and other extended X-ray sources; solar magnetic and velocity field measurement system; solar coronal helium abundance Spacelab experiment; solar UV high resolution telescope and spectroraph; solar UV spectral irradiance monitor; and properties of superfluid helium in zero-G.

A survey of manufacturers of solar thermal energy systems

NASA Technical Reports Server (NTRS)

Levine, N.; Slonski, M. L.

1982-01-01

Sixty-seven firms that had received funding for development of solar thermal energy systems (STES) were surveyed. The effect of the solar thermal technology systems program in accelerating (STES) were assessed. The 54 firms still developing STES were grouped into a production typology comparing the three major technologies with three basic functions. It was discovered that large and small firms were developing primarily central receiver systems, but also typically worked on more than one technology. Most medium-sized firms worked only on distributed systems. Federal support of STES was perceived as necessary to allow producers to take otherwise unacceptable risks. Approximately half of the respondents would drop out of STES if support were terminated, including a disproportionate number of medium-sized firms. A differentiated view of the technology, taking into account differing firm sizes and the various stages of technology development, was suggested for policy and planning purposes.

A survey of manufacturers of solar thermal energy systems

NASA Astrophysics Data System (ADS)

Levine, N.; Slonski, M. L.

1982-08-01

Sixty-seven firms that had received funding for development of solar thermal energy systems (STES) were surveyed. The effect of the solar thermal technology systems program in accelerating (STES) were assessed. The 54 firms still developing STES were grouped into a production typology comparing the three major technologies with three basic functions. It was discovered that large and small firms were developing primarily central receiver systems, but also typically worked on more than one technology. Most medium-sized firms worked only on distributed systems. Federal support of STES was perceived as necessary to allow producers to take otherwise unacceptable risks. Approximately half of the respondents would drop out of STES if support were terminated, including a disproportionate number of medium-sized firms. A differentiated view of the technology, taking into account differing firm sizes and the various stages of technology development, was suggested for policy and planning purposes.

Concentrated solar power in the built environment

NASA Astrophysics Data System (ADS)

Montenon, Alaric C.; Fylaktos, Nestor; Montagnino, Fabio; Paredes, Filippo; Papanicolas, Costas N.

2017-06-01

Solar concentration systems are usually deployed in large open spaces for electricity generation; they are rarely used to address the pressing energy needs of the built environment sector. Fresnel technology offers interesting and challenging CSP energy pathways suitable for the built environment, due to its relatively light weight (<30 kg.m-2) and low windage. The Cyprus Institute (CyI) and Consorzio ARCA are cooperating in such a research program; we report here the construction and integration of a 71kW Fresnel CSP system into the HVAC (Heating, Ventilation, and Air Conditioning) system of a recently constructed office & laboratory building, the Novel Technologies Laboratory (NTL). The multi-generative system will support cooling, heating and hot water production feeding the system of the NTL building, as a demonstration project, part of the STS-MED program (Small Scale Thermal Solar District Units for Mediterranean Communities) financed by the European Commission under the European Neighbourhood and Partnership Instrument (ENPI), CBCMED program.

Studies of new media radiation induced laser. Final Report, 1 February 1979-30 April 1984

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

Han, K.S.; Shiu, Y.J.; Raju, S.R.

Various lasants were investigated especially, 2-iodohepafluoropropane (i-C3F7I) for the direct solar pumped lasers. Optical pumping of iodine laser was achieved using a small flashlamp. Using i-C3F7I as a laser gain medium, threshold inversion density, small signal gain, and laser performance at the elevated temperature were measured. The experimental results and analysis are presented. The iodine laser kinetics of the C3F7I and IBr system were numerically simulated. The concept of a direct solar-pumped laser amplifier using (i-C3F7I) as the laser material was evaluated and several kinetic coefficients for i-C3F7I laser system were reexamined. The results are discussed.

Using ANTS to explore small body populations in the solar system.

NASA Astrophysics Data System (ADS)

Clark, P. E.; Rilee, M.; Truszkowski, W.; Curtis, S.; Marr, G.; Chapman, C.

2001-11-01

ANTS (Autonomous Nano-Technology Swarm), a NASA advanced mission concept, is a large (100 to 1000 member) swarm of pico-class (1 kg) totally autonomous spacecraft that prospect the asteroid belt. Little data is available for asteroids because the vast majority are too small to be observed except in close proximity. Light curves are available for thousands of asteroids, confirmed trajectories for tens of thousands, detailed shape models for approximately ten. Asteroids originated in the transitional region between the inner (rocky) and outer (solidified gases) solar system. Many have remained largely unmodified since formation, and thus have more primitive composition than planetary surfaces. Determination of the systematic distribution of physical and compositional properties within the asteroid population is crucial in the understanding of solar system formation. The traditional exploration approach of using few, large spacecraft for sequential exploration, could be improved. Our far more cost-effective approach utilizes distributed intelligence in a swarm of tiny highly maneuverable spacecraft, each with specialized instrument capability (e.g., advanced computing, imaging, spectrometry). NASA is at the forefront of Intelligent Software Agents (ISAs) research, performing experiments in space and on the ground to advance deliberative and collaborative autonomous control techniques. The advanced development under consideration here is in the use of ISAs at a strategic level, to explore remote frontiers of the solar system, potentially involving a large class of objects such as asteroids. Supervised clusters of spacecraft operate simultaneously within a broadly defined framework of goals to select targets (> 1000) from among available candidates while developing scenarios for studying targets. Swarm members use solar sails to fly directly to asteroids > 1 kilometer in diameter, and then perform maneuvers appropriate for the instrument carried, ranging from hovering to orbiting. Selected members return with data and are replaced as needed.

Report on monitoring and support instruments for solar physics research from Spacelab

NASA Technical Reports Server (NTRS)

1978-01-01

The Quick Reaction and Special Purpose Facility Definition Team for Solar Physics Spacelab Payloads examined a variety of instruments to fulfill the following functions: (1) solar physics research appropriate to Spacelab, (2) correlative data for research in such fields as aeronomy, magnetospheric physics, ionospheric physics, meteorology and climatology, (3) target selection for activity alert monitoring and (4) pointing accuracy monitoring of Spacelab platforms. In this examination the team accepted a number of restrictions and qualifications: (1) the cost of such instruments must be low, so as not to adversely impact the development of new, research class instrumentation in the early Spacelab era; (2) the instruments should be of such a size that they each would occupy a small fraction of a pointing system, and (3) the weight and power consumption of the instruments should also be small. With these restrictions, the instruments chosen are: the visible light telescope and magnetograph, the extreme-ultraviolet telescope, and the solar irradiance monitor.

Review of biased solar array - Plasma interaction studies

NASA Technical Reports Server (NTRS)

Stevens, N. J.

1981-01-01

Possible high voltage surface interactions on the Solar Electric Propulsion System (SEPS) are examined, with particular regard for potential effects on SEPS performance. The SEPS is intended for use for geosynchronous and planetary missions, and derives power from deployed solar cell arrays which are susceptible to collecting ions and electrons from the charged and thermal particle environment of space. The charge exchange plasma which provides the thrust force can also enhance the natural charged particle environment and increase interactions between the thrust system and the biased solar array surface. Tests of small arrays have shown that snapover, where current collection becomes proportional to the panel area, can be avoided by larger cell sizes. Arcing is predicted to diminish with larger array sizes, while the problems of efflux environments are noted to be as yet undefined and require further study.

Solar Radiation on Mars: Tracking Photovoltaic Array

NASA Technical Reports Server (NTRS)

Appelbaum, Joseph; Flood, Dennis J.; Crutchik, Marcos

1994-01-01

A photovoltaic power source for surface-based operation on Mars can offer many advantages. Detailed information on solar radiation characteristics on Mars and the insolation on various types of collector surfaces are necessary for effective design of future planned photovoltaic systems. In this article we have presented analytical expressions for solar radiation calculation and solar radiation data for single axis (of various types) and two axis tracking surfaces and compared the insulation to horizontal and inclined surfaces. For clear skies (low atmospheric dust load) tracking surfaces resulted in higher insolation than stationary surfaces, whereas for highly dusty atmospheres, the difference is small. The insolation on the different types of stationary and tracking surfaces depend on latitude, season and optical depth of the atmosphere, and the duration of system operation. These insolations have to be compared for each mission.

The Evolving Market Structure of the U.S. Residential Solar PV Installation Industry, 2000-2016

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

OShaughnessy, Eric J.

This study uses data on over 900,000 solar PV installations to summarize the evolving market structure of the U.S. residential solar PV installation industry. Over 8,000 companies have installed residential PV systems in the United States. The vast majority of these installers are small local companies. At the same time, a subset of national-scale high-volume PV installation companies hold high market shares. This study examines the factors behind these trends in market concentration, including the role of customer financing options.

An Overview of Solar Sail Propulsion within NASA

NASA Technical Reports Server (NTRS)

Johnson, Les; Swartzlander, Grover A.; Artusio-Glimpse, Alexandra

2013-01-01

Solar Sail Propulsion (SSP) is a high-priority new technology within The National Aeronautics and Space Administration (NASA), and several potential future space missions have been identified that will require SSP. Small and mid-sized technology demonstration missions using solar sails have flown or will soon fly in space. Multiple mission concept studies have been performed to determine the system level SSP requirements for their implementation and, subsequently, to drive the content of relevant technology programs. The status of SSP technology and potential future mission implementation within the United States (US) will be described.

Concept definition study of small Brayton cycle engines for dispersed solar electric power systems

NASA Technical Reports Server (NTRS)

Six, L. D.; Ashe, T. L.; Dobler, F. X.; Elkins, R. T.

1980-01-01

Three first-generation Brayton cycle engine types were studied for solar application: a near-term open cycle (configuration A), a near-term closed cycle (configuration B), and a longer-term open cycle (configuration C). A parametric performance analysis was carried out to select engine designs for the three configurations. The interface requirements for the Brayton cycle engine/generator and solar receivers were determined. A technology assessment was then carried out to define production costs, durability, and growth potential for the selected engine types.

Low cost solar array project silicon materials task. Development of a process for high capacity arc heater production of silicon for solar arrays

NASA Technical Reports Server (NTRS)

Reed, W. H.

1978-01-01

Silicon tetrachloride and a reductant (sodium) will be injected into an arc heated mixture of hydrogen and argon, yielding silicon and gaseous sodium chloride. Detailed characterization of the Sonicore sodium injection nozzle, using water as the test fluid was completed. Results indicated that flow rates of 45 gph sodium and 50 scfm argon should produce sufficiently small droplet sizes. The design effort was also completed for the test system preparation which was divided into two categories: (1) system components and (2) test system-laboratory integration.

TIME DISTRIBUTIONS OF LARGE AND SMALL SUNSPOT GROUPS OVER FOUR SOLAR CYCLES

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

Kilcik, A.; Yurchyshyn, V. B.; Abramenko, V.

2011-04-10

Here we analyze solar activity by focusing on time variations of the number of sunspot groups (SGs) as a function of their modified Zurich class. We analyzed data for solar cycles 20-23 by using Rome (cycles 20 and 21) and Learmonth Solar Observatory (cycles 22 and 23) SG numbers. All SGs recorded during these time intervals were separated into two groups. The first group includes small SGs (A, B, C, H, and J classes by Zurich classification), and the second group consists of large SGs (D, E, F, and G classes). We then calculated small and large SG numbers frommore » their daily mean numbers as observed on the solar disk during a given month. We report that the time variations of small and large SG numbers are asymmetric except for solar cycle 22. In general, large SG numbers appear to reach their maximum in the middle of the solar cycle (phases 0.45-0.5), while the international sunspot numbers and the small SG numbers generally peak much earlier (solar cycle phases 0.29-0.35). Moreover, the 10.7 cm solar radio flux, the facular area, and the maximum coronal mass ejection speed show better agreement with the large SG numbers than they do with the small SG numbers. Our results suggest that the large SG numbers are more likely to shed light on solar activity and its geophysical implications. Our findings may also influence our understanding of long-term variations of the total solar irradiance, which is thought to be an important factor in the Sun-Earth climate relationship.« less

Radiation Environments for Future Human Exploration Throughout the Solar System.

NASA Astrophysics Data System (ADS)

Schwadron, N.; Gorby, M.; Linker, J.; Riley, P.; Torok, T.; Downs, C.; Spence, H. E.; Desai, M. I.; Mikic, Z.; Joyce, C. J.; Kozarev, K. A.; Townsend, L. W.; Wimmer-Schweingruber, R. F.

2016-12-01

Acute space radiation hazards pose one of the most serious risks to future human and robotic exploration. The ability to predict when and where large events will occur is necessary in order to mitigate their hazards. The largest events are usually associated with complex sunspot groups (also known as active regions) that harbor strong, stressed magnetic fields. Highly energetic protons accelerated very low in the corona by the passage of coronal mass ejection (CME)-driven compressions or shocks and from flares travel near the speed of light, arriving at Earth minutes after the eruptive event. Whether these particles actually reach Earth, the Moon, Mars (or any other point) depends on their transport in the interplanetary magnetic field and their magnetic connection to the shock. Recent contemporaneous observations during the largest events in almost a decade show the unique longitudinal distributions of this ionizing radiation broadly distributed from sources near the Sun and yet highly isolated during the passage of CME shocks. Over the last decade, we have observed space weather events as the solar wind exhibits extremely low densities and magnetic field strengths, representing states that have never been observed during the space age. The highly abnormal solar activity during cycles 23 and 24 has caused the longest solar minimum in over 80 years and continues into the unusually small solar maximum of cycle 24. As a result of the remarkably weak solar activity, we have also observed the highest fluxes of galactic cosmic rays in the space age and relatively small particle radiation events. We have used observations from LRO/CRaTER to examine the implications of these highly unusual solar conditions for human space exploration throughout the inner solar system. While these conditions are not a show-stopper for long-duration missions (e.g., to the Moon, an asteroid, or Mars), galactic cosmic ray radiation remains a significant and worsening factor that limits mission durations. If the heliospheric magnetic field continues to weaken over time, as is likely, then allowable mission durations will decrease correspondingly. Thus, we examine the rapidly changing radiation environment and its implications for human exploration destinations throughout the inner solar system.

10 CFR 470.10 - Establishment of program.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Solar Energy of DOE, an appropriate technology small grants program for the purpose of encouraging development and demonstration of, and the dissemination of information with respect to, energy-related systems...

10 CFR 470.10 - Establishment of program.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Solar Energy of DOE, an appropriate technology small grants program for the purpose of encouraging development and demonstration of, and the dissemination of information with respect to, energy-related systems...

Development of a thermal storage module using modified anhydrous sodium hydroxide

NASA Technical Reports Server (NTRS)

Rice, R. E.; Rowny, P. E.

1980-01-01

The laboratory scale testing of a modified anhydrous NaOH latent heat storage concept for small solar thermal power systems such as total energy systems utilizing organic Rankine systems is discussed. A diagnostic test on the thermal energy storage module and an investigation of alternative heat transfer fluids and heat exchange concepts are specifically addressed. A previously developed computer simulation model is modified to predict the performance of the module in a solar total energy system environment. In addition, the computer model is expanded to investigate parametrically the incorporation of a second heat exchange inside the module which will vaporize and superheat the Rankine cycle power fluid.

Binary Systems as Test-Beds of Gravity Theories

NASA Astrophysics Data System (ADS)

Damour, Thibault

The discovery of binary pulsars in 1974 [1] opened up a new testing ground for relativistic gravity. Before this discovery, the only available testing ground for relativistic gravity was the solar system. As Einstein's theory of General Relativity (GR) is one of the basic pillars of modern science, it deserves to be tested, with the highest possible accuracy, in all its aspects. In the solar sys tem, the gravitational field is slowly varying and represents only a very small deformation of a flat spacetime. As a consequence, solar system tests can only probe the quasi-stationary (non-radiative) weak-field limit of relativis tic gravity. By contrast binary systems containing compact objects (neutron stars or black holes) involve spacetime domains (inside and near the compact objects) where the gravitational field is strong. Indeed, the surface relativistic gravitational field h 00 ≈ 2 GM/c 2 R of a neutron star is of order 0.4, which is close to the one of a black hole (2GM/c 2 R = 1) and much larger than the surface gravitational fields of solar system bodies: (2GM/c 2 R)Sun ˜ 10-6, (2GM/c 2 R)Earth ˜ 10-9. In addition, the high stability of “pulsar clocks” has made it possible to monitor the dynamics of its orbital motion down to a precision allowing one to measure the small (˜ (v/c)5) orbital effects linked to the propagation of the gravitational field at the velocity of light between the pulsar and its companion.

Modeling and Observations of Debris Disks

NASA Astrophysics Data System (ADS)

Moro-Martín, Amaya

2009-08-01

Debris disks are disks of dust observed around mature main sequence stars (generally A to K2 type). They are evidence that these stars harbor a reservoir of dust-producing plantesimals on spatial scales that are similar to those found for the small-body population of our solar system. Debris disks present a wide range of sizes and structural features (inner cavities, warps, offsets, rings, clumps) and there is growing evidence that, in some cases, they might be the result of the dynamical perturbations of a massive planet. Our solar system also harbors a debris disk and some of its properties resemble those of extra-solar debris disks. The study of these disks can shed light on the diversity of planetary systems and can help us place our solar system into context. This contribution is an introduction to the debris disk phenomenon, including a summary of debris disks main properties (§1-based mostly on results from extensive surveys carried out with Spitzer), and a discussion of what they can teach us about the diversity of planetary systems (§2).

Thermal Development Test of the NEXT PM1 Ion Engine

NASA Technical Reports Server (NTRS)

Anderson, John R.; Snyder, John S.; VanNoord, Jonathan L.; Soulas, George C.

2010-01-01

NASA's Evolutionary Xenon Thruster (NEXT) is a next-generation high-power ion propulsion system under development by NASA as a part of the In-Space Propulsion Technology Program. NEXT is designed for use on robotic exploration missions of the solar system using solar electric power. Potential mission destinations that could benefit from a NEXT Solar Electric Propulsion (SEP) system include inner planets, small bodies, and outer planets and their moons. This range of robotic exploration missions generally calls for ion propulsion systems with deep throttling capability and system input power ranging from 0.6 to 25 kW, as referenced to solar array output at 1 Astronomical Unit (AU). Thermal development testing of the NEXT prototype model 1 (PM1) was conducted at JPL to assist in developing and validating a thruster thermal model and assessing the thermal design margins. NEXT PM1 performance prior to, during and subsequent to thermal testing are presented. Test results are compared to the predicted hot and cold environments expected missions and the functionality of the thruster for these missions is discussed.

First Solar System Results of the Spitzer Space Telescope

NASA Technical Reports Server (NTRS)

VanCleve, J.; Cruikshank, D. P.; Stansberry, J. A.; Burgdorf, M. J.; Devost, D.; Emery, J. P.; Fazio, G.; Fernandez, Y. R.; Glaccum, W.; Grillmair, C.

2004-01-01

The Spitzer Space Telescope, formerly known as SIRTF, is now operational and delivers unprecedented sensitivity for the observation of Solar System targets. Spitzer's capabilities and first general results were presented at the January 2004 AAS meeting. In this poster, we focus on Spitzer's performance for moving targets, and the first Solar System results. Spitzer has three instruments, IRAC, IRS, and MIPS. IRAC (InfraRed Array Camera) provides simultaneous images at wavelengths of 3.6, 4.5, 5.8, and 8.0 microns. IRS (InfraRed Spectrograph) has 4 modules providing low-resolution (R=60-120) spectra from 5.3 to 40 microns, high-resolution (R=600) spectra from 10 to 37 m, and an autonomous target acquisition system (PeakUp) which includes small-field imaging at 15 m. MIPS (Multiband Imaging Photometer for SIRTF) does imaging photometry at 24, 70, and 160 m and low-resolution (R=15-25) spectroscopy (SED) between 55 and 96 microns. Guaranteed Time Observer (GTO) programs include the moons of the outer Solar System, Pluto, Centaurs, Kuiper Belt Objects, and comets

Enhancing Performance of Large-Area Organic Solar Cells with Thick Film via Ternary Strategy.

PubMed

Zhang, Jianqi; Zhao, Yifan; Fang, Jin; Yuan, Liu; Xia, Benzheng; Wang, Guodong; Wang, Zaiyu; Zhang, Yajie; Ma, Wei; Yan, Wei; Su, Wenming; Wei, Zhixiang

2017-06-01

Large-scale fabrication of organic solar cells requires an active layer with high thickness tolerability and the use of environment-friendly solvents. Thick films with high-performance can be achieved via a ternary strategy studied herein. The ternary system consists of one polymer donor, one small molecule donor, and one fullerene acceptor. The small molecule enhances the crystallinity and face-on orientation of the active layer, leading to improved thickness tolerability compared with that of a polymer-fullerene binary system. An active layer with 270 nm thickness exhibits an average power conversion efficiency (PCE) of 10.78%, while the PCE is less than 8% with such thick film for binary system. Furthermore, large-area devices are successfully fabricated using polyethylene terephthalate (PET)/Silver gride or indium tin oxide (ITO)-based transparent flexible substrates. The product shows a high PCE of 8.28% with an area of 1.25 cm 2 for a single cell and 5.18% for a 20 cm 2 module. This study demonstrates that ternary organic solar cells exhibit great potential for large-scale fabrication and future applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Assessment of High-Voltage Photovoltaic Technologies for the Design of a Direct Drive Hall Effect Thruster Solar Array

NASA Technical Reports Server (NTRS)

Mikellides, I. G.; Jongeward, G. A.; Schneider, T.; Carruth, M. R.; Peterson, T.; Kerslake, T. W.; Snyder, D.; Ferguson, D.; Hoskins, A.

2004-01-01

A three-year program to develop a Direct Drive Hall-Effect Thruster system (D2HET) begun in 2001 as part of the NASA Advanced Cross-Enterprise Technology Development initiative. The system, which is expected to reduce significantly the power processing, complexity, weight, and cost over conventional low-voltage systems, will employ solar arrays that operate at voltages higher than (or equal to) 300 V. The lessons learned from the development of the technology also promise to become a stepping-stone for the production of the next generation of power systems employing high voltage solar arrays. This paper summarizes the results from experiments conducted mainly at the NASA Marshal Space Flight Center with two main solar array technologies. The experiments focused on electron collection and arcing studies, when the solar cells operated at high voltages. The tests utilized small coupons representative of each solar array technology. A hollow cathode was used to emulate parts of the induced environment on the solar arrays, mostly the low-energy charge-exchange plasma (1012-1013 m-3 and 0.5-1 eV). Results and conclusions from modeling of electron collection are also summarized. The observations from the total effort are used to propose a preliminary, new solar array design for 2 kW and 30-40 kW class, deep space missions that may employ a single or a cluster of Hall- Effect thrusters.

Modelling and control synthesis of a micro-combined heat and power interface for a concentrating solar power system in off-grid rural power applications

NASA Astrophysics Data System (ADS)

Prinsloo, Gerro; Dobson, Robert; Brent, Alan; Mammoli, Andrea

2016-05-01

Concentrating solar power co-generation systems have been identified as potential stand-alone solar energy supply solutions in remote rural energy applications. This study describes the modelling and synthesis of a combined heat and power Stirling CSP system in order to evaluate its potential performance in small off-grid rural village applications in Africa. This Stirling micro-Combined Heat and Power (micro-CHP) system has a 1 kW electric capacity, with 3 kW of thermal generation capacity which is produced as waste heat recovered from the solar power generation process. As part of the development of an intelligent microgrid control and distribution solution, the Trinum micro-CHP system and other co-generation systems are systematically being modelled on the TRNSYS simulation platform. This paper describes the modelling and simulation of the Trinum micro-CHP configuration on TRNSYS as part of the process to develop the control automation solution for the smart rural microgrid in which the Trinum will serve as a solar powerpack. The results present simulated performance outputs for the Trinum micro-CHP system for a number of remote rural locations in Africa computed from real-time TRNSYS solar irradiation and weather data (yearly, monthly, daily) for the relevant locations. The focus of this paper is on the parametric modelling of the Trinum Stirling micro-CHP system, with specific reference to this system as a TRNSYS functional block in the microgrid simulation. The model is used to forecast the solar energy harvesting potential of the Trinum micro-CHP unit at a number of remote rural sites in Africa.

The Planetary Terrestrial Analogues Library (PTAL)

NASA Astrophysics Data System (ADS)

Werner, S. C.; Dypvik, H.; Poulet, F.; Rull Perez, F.; Bibring, J.-P.; Bultel, B.; Casanova Roque, C.; Carter, J.; Cousin, A.; Guzman, A.; Hamm, V.; Hellevang, H.; Lantz, C.; Lopez-Reyes, G.; Manrique, J. A.; Maurice, S.; Medina Garcia, J.; Navarro, R.; Negro, J. I.; Neumann, E. R.; Pilorget, C.; Riu, L.; Sætre, C.; Sansano Caramazana, A.; Sanz Arranz, A.; Sobron Grañón, F.; Veneranda, M.; Viennet, J.-C.; PTAL Team

2018-04-01

The Planetary Terrestrial Analogues Library project aims to build and exploit a spectral data base for the characterisation of the mineralogical and geological evolution of terrestrial planets and small solar system bodies.

Control of a solar-energy-supplied electrical-power system without intermediate circuitry

NASA Astrophysics Data System (ADS)

Leistner, K.

A computer control system is developed for electric-power systems comprising solar cells and small numbers of users with individual centrally controlled converters (and storage facilities when needed). Typical system structures are reviewed; the advantages of systems without an intermediate network are outlined; the demands on a control system in such a network (optimizing generator working point and power distribution) are defined; and a flexible modular prototype system is described in detail. A charging station for lead batteries used in electric automobiles is analyzed as an example. The power requirements of the control system (30 W for generator control and 50 W for communications and distribution control) are found to limit its use to larger networks.

Terrestrial outgoing radiation measurements with small satellite mission

NASA Astrophysics Data System (ADS)

Zhu, Ping; Dewitte, Steven; Karatekin, Ozgur; Chevalier, André; Conscience, Christian

2015-04-01

The solar force is the main driver of the Earth's climate. For a balanced climate system, the incoming solar radiation is equal to the sum of the reflected visible and reemitted thermal radiation at top of the atmosphere (TOA). Thus the energy imbalance plays an important role to diagnose the health of nowadays climate. However it remains a challenge to directly track the small Energy imbalance in Earth's Radiation Budget (EIERB) from space due to the complicities of the Earth's climate system and the limitation on long term stability of space instrument. The terrestrial outgoing radiation (TOR) has been recoded with a Bolometric Oscillation Sensor onboard PICAD microsatellite. In this presentation, we will report the three years TOR observed with PICARD-BOS and its further comparison with the CERES product. However the data acquired from this mission is still not enough to derive the EIERB. But the heritage gained from this experiment shields a light on the EIERB tracking with the small satellite even a cubesat mission.

Luminescent solar concentrators and all-inorganic nanoparticle solar cells for solar energy harvesting

NASA Astrophysics Data System (ADS)

Sholin, Veronica

Increasing energy demand and the parallel increase of greenhouse gas emissions are challenging researchers to find new and cleaner energy sources. Solar energy harvesting is arguably the most promising candidate for replacing fossil-fuel power generation. Photovoltaics are the most direct way of collecting solar energy; cost continues to hinder large-scale implementation of photovoltaics, however. Therefore, alternative technologies that will allow the extraction of solar power, while maintaining the overall costs of fabrication, installation, collection, and distribution low, must be explored. This thesis focuses on the fabrication and testing of two types of devices that step up to this challenge: the luminescent solar concentrator (LSC) and all-inorganic nanoparticle solar cells. In these devices I make use of novel materials, semiconducting polymers and inorganic nanoparticles, both of which have lower costs than the crystalline materials used in the fabrication of traditional photovoltaics. Furthermore, the cost of manufacturing LSCs and the nanoparticle solar cells is lower than the manufacturing cost of traditional optics-based concentrators and crystalline solar cells. An LSC is essentially a slab of luminescent material that acts as a planar light pipe. The LSC absorbs incoming photons and channels fluoresced photons toward appropriately located solar cells, which perform the photovoltaic conversion. By covering large areas with relatively inexpensive fluorescing organic dyes or semiconducting polymers, the area of solar cell needed is greatly reduced. Because semiconducting polymers and quantum dots may have small absorption/emission band overlaps, tunable absorption, and longer lifetimes, they are good candidates for LSC fabrication, promising improvement with respect to laser dyes traditionally used to fabricate LSCs. Here the efficiency of LSCs consisting of liquid solutions of semiconducting polymers encased in glass was measured and compared to the efficiency of LSCs based on small molecule laser dyes and on quantum dots. Factors affecting the optical efficiency of the system such as the luminescing properties of the fluorophors were examined. The experimental results were compared to Monte-Carlo simulations. Our results suggest that commercially available quantum dots cannot serve as viable LSC dyes because of large absorption/emission band overlap and relatively low quantum yield. Materials such as Red F demonstrate that semi-conducting polymers with high quantum yield and small absorption/emission band overlap are good candidates for LSCs. Recently, a solar cell system based purely on CdSe and Cite nanoparticles as the absorbing materials was proposed ans it was suggested that its operational mechanism was that of polymer donor/acceptor systems. Here we present solar cells consisting of a sintered active bilayer of CdSe and PbSe nanoparticles in the structure ITO/CdSe/interlayer/PbSe/Al, where an interlayer of LiF or Al2O3 was found necessary to prevent low shunt resistance from suppressing the photovoltaic behavior. We fabricated unoptimized solar cells with a short-circuit current of 6 mA/cm2, an open-circuit voltage of 0.18 V, and a fill factor of 41%. External quantum efficiency spectra revealed that photons from the infrared portion of the spectrum were not collected, suggesting that the low bandgap PbSe film did not contribute to the photocurrent of the structure despite exhibiting photoconductivity. Other measurements, however, showed that the PbSe film was indeed necessary to produce a photovoltage and transport electrons. Through sintering, the nanoparticle films acquired bandgaps similar to those of the corresponding bulk materials and became more conductive. Because the PbSe films were found to be considerably more conductive than the CdSe ones, we suggest that the PbSe layer is effectively behaving like a low conductivity electrical contact. Therefore, in contrast to the photovoltaics presented in the seminal research on CdSe/Cite solar cells, the CdSe/PbSe solar cell system presented here does not follow typical type-II heterojunction donor/acceptor models used to describe organic polymer solar cells.

On-orbit solar calibrations using the Aqua Clouds and Earth's Radiant Energy System (CERES) in-flight calibration system

NASA Astrophysics Data System (ADS)

Wilson, Robert S.; Priestley, Kory J.; Thomas, Susan; Hess, Phillip

2009-08-01

The Clouds and the Earth's Radiant Energy System (CERES) spacecraft scanning thermistor bolometers were used to measure earth-reflected solar and earth-emitted longwave radiances, at satellite altitude. The bolometers measured the earth radiances in the broadband shortwave solar (0.3 - 5.0 micrometers) and total (0.3->100 micrometers) spectral bands as well as in the (8 - 12 micrometers) water vapor window spectral band over geographical footprints as small as 10 kilometers at nadir. In May 2002, the fourth and fifth sets of CERES bolometers were launched aboard the Aqua spacecraft. Ground vacuum calibrations defined the initial count conversion coefficients that were used to convert the bolometer output voltages into filtered earth radiances. The mirror attenuator mosaic (MAM), a solar diffuser plate, was built into the CERES instrument package calibration system in order to define in-orbit shifts or drifts in the sensor responses. The shortwave and total sensors are calibrated using the solar radiances reflected from the MAM's. Each MAM consists of baffle-solar diffuser plate systems, which guide incoming solar radiances into the instrument fields-of-view of the shortwave and total wave sensor units. The MAM diffuser reflecting type surface consists of an array of spherical aluminum mirror segments, which are separated by a Merck Black A absorbing surface, overcoated with silicon dioxide. Temperature sensors are located in each MAM plate and baffle. The CERES MAM wass designed to yield calibration precisions approaching .5 percent for the total and shortwave detectors. In this paper, the MAM solar calibration procedures are presented along with on-orbit results. Comparisons are also made between the Aqua,Terra and the Tropical Rainfall Measurement Mission (TRMM) CERES MAM solar calibrations.

Ultra-modular 500m2 heliostat field for high flux/high temperature solar-driven processes

NASA Astrophysics Data System (ADS)

Romero, Manuel; González-Aguilar, José; Luque, Salvador

2017-06-01

The main objective of the European Project SUN-to-LIQUID is the scale-up and experimental demonstration of the complete process chain to solar liquid fuels from H2O and CO2. This implies moving from a 4 kW laboratory setup to a pre-commercial plant including a heliostat field. The small power and high irradiance onto the focal spot is forcing the optical design to behave half way between a large solar furnace and an extremely small central receiver system. The customized heliostat field makes use of the most recent developments on small size heliostats and a tower with reduced optical height (15 m) to minimize visual impact. A heliostat field of 250kWth (500 m2 reflective surface) has been built adjacent to IMDEA Energy premises at the Technology Park of Móstoles, Spain, and consists of 169 small size heliostats (1.9 m × 1.6 m). In spite of the small size and compactness of the field, when all heliostats are aligned, it is possible to fulfil the specified flux above 2500 kW/m2 for at least 50 kW and an aperture of 16 cm, with a peak flux of 3000 kW/m2.

Meteoritic Evidence for Injection of Trans-Neptunian Objects into the Inner Solar System

NASA Technical Reports Server (NTRS)

Zolensky, M.; Johnson, J.; Ziegler, K.; Chan, Q.; Kebukawa, Y.; Bottke, W.; Fries, M.; Martinez, J.; Le, L.

2018-01-01

There is excellent evidence that a dynamical instability in the early solar system led to gravitational interactions between the giant planets and trans-Neptunian planetesimals. Giant planetary migration triggered by the instability dispersed a disk of primordial trans-Neptunian object (TNOs) and created a number of small body reservoirs (e.g. the Kuiper Belt, scattered disk, irregular satellites, and the Jupiter/Neptune Trojan populations). It also injected numerous bodies into the main asteroid belt, where modeling shows they can successfully reproduce the observed P and D-type asteroid populations.

Lunar Get Away Special (GAS) spacecraft

NASA Technical Reports Server (NTRS)

Nock, K. T.; Aston, G.; Salazar, R. P.; Stella, P. M.

1987-01-01

A new approach to the resumption of Lunar missions is discussed which relies upon Shuttle Get-Away-Special Canisters for launch and solar electric ion propulsion for slow orbit transfer to low Lunar orbit. The technique of orbit transfer is outlined along with a summary of a mission profile for a first mission which could carry a Gamma Ray Spectrometer. System design constraints are discussed followed by a description of the low mass spacecraft concept which has been developed. Particular emphasis is placed upon describing the small solar electric, xenon ion propulsion system.

SPS attitude control and stationkeeping: Requirements and tradeoffs

NASA Technical Reports Server (NTRS)

Oglevie, R. E.

1980-01-01

The dominant control requirements of solar power satellites change appreciably relative to small contemporary spacecraft. Trade studies and analyses illustrated preferred control approaches. It was found that the geosynchronous equatorial orbit is preferred over the alternative orbits considered, that the solar pressure orbit perturbation dominates stationkeeping propulsion requirements and that a combined AC and SK system using ion electric propulsion can satisfy the attitude control requirements. It was also found that control system/structural dynamic interaction stability can be obtained through frequency separation with reasonable structural dynamic requirements and simplify spacecraft design.

Solar Electric Propulsion (SEP) Systems for SMD Mission Needs. Technology Infusion Study.

NASA Technical Reports Server (NTRS)

Anderson, David

2014-01-01

Two presentations for SBAG and OPAG meetings: 1) Solar Electric Propulsion Systems for SMD Missions, and 2) Technology Infusion Study - Draft Findings Recommendation Small Bodies Assessment Group (SBAG) meeting is January 9th in Washington D.C., and the Outer Planets Assessment Group (OPAG) meeting is January 23-14 in Tucson, AZ. NASA sponsors these assessment groups, through the NRC, for the science community to assess and provide advice. These talks are to provide a status of 2 NASA activities, and to seek feedback from the respective science communities.

Xatcobeo: Small Mechanisms for CubeSat Satellites - Antenna and Solar Array Deployment

NASA Technical Reports Server (NTRS)

EncinasPlaza, Jose Miguel; VilanVilan, Jose Antonio; AquadoAgelet, Fernando; BrandiaranMancheno, Javier; LopezEstevez, Miguel; MartinezFernandez, Cesar; SarmientoAres, Fany

2010-01-01

The Xatcobeo project, which includes the mechanisms dealt with here, is principally a university project to design and construct a CubeSat 1U-type satellite. This work describes the design and operational features of the system for antenna storage and deployment, and the design and simulations of the solar array deployment system. It explains the various problems faced and solutions adopted, with a view to providing valid data for any other applications that could find them useful, be they of a similar nature or not.

New Markets for Solar Photovoltaic Power Systems

NASA Astrophysics Data System (ADS)

Thomas, Chacko; Jennings, Philip; Singh, Dilawar

2007-10-01

Over the past five years solar photovoltaic (PV) power supply systems have matured and are now being deployed on a much larger scale. The traditional small-scale remote area power supply systems are still important and village electrification is also a large and growing market but large scale, grid-connected systems and building integrated systems are now being deployed in many countries. This growth has been aided by imaginative government policies in several countries and the overall result is a growth rate of over 40% per annum in the sales of PV systems. Optimistic forecasts are being made about the future of PV power as a major source of sustainable energy. Plans are now being formulated by the IEA for very large-scale PV installations of more than 100 MW peak output. The Australian Government has announced a subsidy for a large solar photovoltaic power station of 154 MW in Victoria, based on the concentrator technology developed in Australia. In Western Australia a proposal has been submitted to the State Government for a 2 MW photovoltaic power system to provide fringe of grid support at Perenjori. This paper outlines the technologies, designs, management and policies that underpin these exciting developments in solar PV power.

DARe: Dark Asteroid Rendezvous

NASA Technical Reports Server (NTRS)

Noll, K. S.; McFadden, L. A.; Rhoden, A. R.; Lim, L. F.; Boynton, W. V.; Carter, L. M.; Collins, G.; Englander, J. A.; Goossens, S. A.; Grundy, W. M.;

A distributed big data storage and data mining framework for solar-generated electricity quantity forecasting

NASA Astrophysics Data System (ADS)

Wang, Jianzong; Chen, Yanjun; Hua, Rui; Wang, Peng; Fu, Jia

2012-02-01

Photovoltaic is a method of generating electrical power by converting solar radiation into direct current electricity using semiconductors that exhibit the photovoltaic effect. Photovoltaic power generation employs solar panels composed of a number of solar cells containing a photovoltaic material. Due to the growing demand for renewable energy sources, the manufacturing of solar cells and photovoltaic arrays has advanced considerably in recent years. Solar photovoltaics are growing rapidly, albeit from a small base, to a total global capacity of 40,000 MW at the end of 2010. More than 100 countries use solar photovoltaics. Driven by advances in technology and increases in manufacturing scale and sophistication, the cost of photovoltaic has declined steadily since the first solar cells were manufactured. Net metering and financial incentives, such as preferential feed-in tariffs for solar-generated electricity; have supported solar photovoltaics installations in many countries. However, the power that generated by solar photovoltaics is affected by the weather and other natural factors dramatically. To predict the photovoltaic energy accurately is of importance for the entire power intelligent dispatch in order to reduce the energy dissipation and maintain the security of power grid. In this paper, we have proposed a big data system--the Solar Photovoltaic Power Forecasting System, called SPPFS to calculate and predict the power according the real-time conditions. In this system, we utilized the distributed mixed database to speed up the rate of collecting, storing and analysis the meteorological data. In order to improve the accuracy of power prediction, the given neural network algorithm has been imported into SPPFS.By adopting abundant experiments, we shows that the framework can provide higher forecast accuracy-error rate less than 15% and obtain low latency of computing by deploying the mixed distributed database architecture for solar-generated electricity.

Properties of solar generators with reflectors and radiators

NASA Astrophysics Data System (ADS)

Ebeling, W. D.; Rex, D.; Bierfischer, U.

1980-06-01

Radiation cooled concentrator systems using silicon and GaAs cells were studied. The principle of radiation cooling by the reflector surfaces is discussed for cylindrical parabolic reflectors (SARA), truncated hexagonal pyramids, and a small trough configuration. Beam paths, collection properties for imperfect orientation, and thermal optimization parameters were analyzed. The three concentrating systems with radiation cooling offer advantages over the plane panel and over the large trough. With silicon solar cells they exhibit considerably lower solar cell consumption per Kw and also lower mass per kW. With GaAs cells the SARA system reduces the number of solar cells needed per kW to less than 10%. Also in all other cases SARA offers the best values for alpha and F sub sol, as long as narrow angular tolerances of the panel orientation can be met. Analysis of the energy collecting properties for imperfect orientation shows the superiority of the hexagonal concentrator. This device can produce power for even large angles between the sun and the panel normal.

Asymptotic Giant Branch stars as a source of short-lived radioactive nuclei in the solar nebula

NASA Astrophysics Data System (ADS)

Wasserburg, G. J.; Busso, M.; Gallino, R.; Raiteri, C. M.

1994-03-01

We carried out a theoretical evaluation of the contribution of Asymptotic Giant Branch (AGB) stars to some short-lived (106 less than or equal to Tau-bar less than or equal to 2 x 107 yr) isotopes in the Interstellar Medium (ISM) and in the early solar system using stellar model calculations for thermally pulsing evolutionary phases of low-mass stars. The yields of s-process nuclei in the convective He-shell for different neutron exposures tau0 were obtained, and AGB stars were shown to produce several radioactive nuclei (especially Pd-107, Pb-205, Fe-60, Zr-93, Tc-99, Cs-135, and Hf-182) in diferent amounts. Assuming either contamination of the solar nebula from a single AGB star or models for continuous injection and mixing from many stars into the ISM, we calculate the ratios of radioactive to stable nuclei at the epoch of the Sun's formation. The dilution factor between the AGB ejecta and the early solar system matter is obtained by matching the observed Pd-107/Pd-108 and depends on the value of tau0. It is found that small masses MHe of He-shell material (10-4-10-7 solar mass) enriched in s-process nuclei are sufficient to contaminate 1 solar mass of the ISM to produce the Pd-107 found in the early solar system. Predictions are made for all of the other radioactive isotopes. The optimal model to explain several observed radioactive species at different states of the proto-solar nebula involves a single AGB star with a low neutron exposure (tau0 = 0.03 mbarn-1) which contaminated the cloud with a dilution factor of MHe/solar mass approximately 1.5 x 10-4. This will also contribute newly synthesized stable s-process nuclei in the amount of approximately 10-4 of their abundances already present in the proto-solar cloud. Variations in the degree of homogenization (approximately 30%) of the injected material may account for some of the small general isotopic anomalies found in meteorites. It is also found that Fe-60 is produced in small but significant quantities that may be sufficient to explain the observations if the time elapsed delta from the contamination of the ISM to the formation of protoplanetary bodies is not higher than delta = 5 x 106 yr. If delta is longer, up to 10 x 106 yr, this would require the single AGB star to experience enhanced neutron densities (nn approximately 3 x 109n/cu cm) in the s-processing zone in order to compensate for the branching at Fe-59. The alternative model of long-term continuous ejection of matter from many AGB stars does not appear to match the observations. We also estimate the Al-26 production from the H-shell and find that the Al-26 abundance in the early solar system may be readily explained in a self-consistent manner. Moreover, Al-26 from AGB stars may contribute substantially to the galactic Al-26 gamma-source, while no significant gamma-flux from Co-60 (deriving from Fe-60 decay) is to be expected.

Refraction-Assisted Solar Thermoelectric Generator based on Phase-Change Lens

PubMed Central

Kim, Myoung-Soo; Kim, Min-Ki; Jo, Sung-Eun; Joo, Chulmin; Kim, Yong-Jun

2016-01-01

Solar thermoelectric generators (STEGs), which are used for various applications, (particularly small size electronic devices), have optical concentration systems for high energy conversion efficiency. In this study, a refraction-assisted STEG (R-STEG) is designed based on phase-change materials. As the phase-change material (PCM) changes phase from solid to liquid, its refractive index and transmittance also change, resulting in changes in the refraction of the sunlight transmitted through it, and concentration of solar energy in the phase-change lens. This innovative design facilitates double focusing the solar energy through the optical lens and a phase-change lens. This mechanism resulted in the peak energy conversion efficiencies of the R-STEG being 60% and 86% higher than those of the typical STEG at solar intensities of 1 kW m−2 and 1.5 kW m−2, respectively. In addition, the energy stored in PCM can help to generate steady electrical energy when the solar energy was removed. This work presents significant progress regarding the optical characteristic of PCM and optical concentration systems of STEGs. PMID:27283350

Refraction-Assisted Solar Thermoelectric Generator based on Phase-Change Lens.

PubMed

Kim, Myoung-Soo; Kim, Min-Ki; Jo, Sung-Eun; Joo, Chulmin; Kim, Yong-Jun

2016-06-10

Solar thermoelectric generators (STEGs), which are used for various applications, (particularly small size electronic devices), have optical concentration systems for high energy conversion efficiency. In this study, a refraction-assisted STEG (R-STEG) is designed based on phase-change materials. As the phase-change material (PCM) changes phase from solid to liquid, its refractive index and transmittance also change, resulting in changes in the refraction of the sunlight transmitted through it, and concentration of solar energy in the phase-change lens. This innovative design facilitates double focusing the solar energy through the optical lens and a phase-change lens. This mechanism resulted in the peak energy conversion efficiencies of the R-STEG being 60% and 86% higher than those of the typical STEG at solar intensities of 1 kW m(-2) and 1.5 kW m(-2), respectively. In addition, the energy stored in PCM can help to generate steady electrical energy when the solar energy was removed. This work presents significant progress regarding the optical characteristic of PCM and optical concentration systems of STEGs.

Distributed solar photovoltaic array location and extent dataset for remote sensing object identification

PubMed Central

Bradbury, Kyle; Saboo, Raghav; L. Johnson, Timothy; Malof, Jordan M.; Devarajan, Arjun; Zhang, Wuming; M. Collins, Leslie; G. Newell, Richard

2016-01-01

Earth-observing remote sensing data, including aerial photography and satellite imagery, offer a snapshot of the world from which we can learn about the state of natural resources and the built environment. The components of energy systems that are visible from above can be automatically assessed with these remote sensing data when processed with machine learning methods. Here, we focus on the information gap in distributed solar photovoltaic (PV) arrays, of which there is limited public data on solar PV deployments at small geographic scales. We created a dataset of solar PV arrays to initiate and develop the process of automatically identifying solar PV locations using remote sensing imagery. This dataset contains the geospatial coordinates and border vertices for over 19,000 solar panels across 601 high-resolution images from four cities in California. Dataset applications include training object detection and other machine learning algorithms that use remote sensing imagery, developing specific algorithms for predictive detection of distributed PV systems, estimating installed PV capacity, and analysis of the socioeconomic correlates of PV deployment. PMID:27922592

SMART Solar Sail

NASA Technical Reports Server (NTRS)

Curtis, Steven A.

2005-01-01

A report summarizes the design concept of a super miniaturized autonomous reconfigurable technology (SMART) solar sail a proposed deployable, fully autonomous solar sail for use in very fine station keeping of a spacecraft. The SMART solar sail would include a reflective film stretched among nodes of a SMART space frame made partly of nanotubule struts. A microelectromechanical system (MEMS) at each vertex of the frame would spool and unspool nanotubule struts between itself and neighboring nodes to vary the shape of the frame. The MEMSs would be linked, either wirelessly or by thin wires within the struts, to an evolvable neural software system (ENSS) that would control the MEMSs to reconfigure the sail as needed. The solar sail would be highly deformable from an initially highly compressed configuration, yet also capable of enabling very fine maneuvering of the spacecraft by means of small sail-surface deformations. The SMART Solar Sail would be connected to the main body of the spacecraft by a SMART multi-tether structure, which would include MEMS actuators like those of the frame plus tethers in the form of longer versions of the struts in the frame.

Distributed solar photovoltaic array location and extent dataset for remote sensing object identification

NASA Astrophysics Data System (ADS)

Bradbury, Kyle; Saboo, Raghav; L. Johnson, Timothy; Malof, Jordan M.; Devarajan, Arjun; Zhang, Wuming; M. Collins, Leslie; G. Newell, Richard

2016-12-01

Earth-observing remote sensing data, including aerial photography and satellite imagery, offer a snapshot of the world from which we can learn about the state of natural resources and the built environment. The components of energy systems that are visible from above can be automatically assessed with these remote sensing data when processed with machine learning methods. Here, we focus on the information gap in distributed solar photovoltaic (PV) arrays, of which there is limited public data on solar PV deployments at small geographic scales. We created a dataset of solar PV arrays to initiate and develop the process of automatically identifying solar PV locations using remote sensing imagery. This dataset contains the geospatial coordinates and border vertices for over 19,000 solar panels across 601 high-resolution images from four cities in California. Dataset applications include training object detection and other machine learning algorithms that use remote sensing imagery, developing specific algorithms for predictive detection of distributed PV systems, estimating installed PV capacity, and analysis of the socioeconomic correlates of PV deployment.

Distributed solar photovoltaic array location and extent dataset for remote sensing object identification.

PubMed

Bradbury, Kyle; Saboo, Raghav; L Johnson, Timothy; Malof, Jordan M; Devarajan, Arjun; Zhang, Wuming; M Collins, Leslie; G Newell, Richard

2016-12-06

Earth-observing remote sensing data, including aerial photography and satellite imagery, offer a snapshot of the world from which we can learn about the state of natural resources and the built environment. The components of energy systems that are visible from above can be automatically assessed with these remote sensing data when processed with machine learning methods. Here, we focus on the information gap in distributed solar photovoltaic (PV) arrays, of which there is limited public data on solar PV deployments at small geographic scales. We created a dataset of solar PV arrays to initiate and develop the process of automatically identifying solar PV locations using remote sensing imagery. This dataset contains the geospatial coordinates and border vertices for over 19,000 solar panels across 601 high-resolution images from four cities in California. Dataset applications include training object detection and other machine learning algorithms that use remote sensing imagery, developing specific algorithms for predictive detection of distributed PV systems, estimating installed PV capacity, and analysis of the socioeconomic correlates of PV deployment.

The Evolving Market Structure of the U.S. Residential Solar PV Installation Industry, 2000-2016

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

OShaughnessy, Eric J

Market structure refers to the number of firms and the distribution of market shares among firms within an industry. In The Evolving Market Structure of the U.S. Residential Solar PV Installation Industry, 2000-2016, we examine market structure in the context of residential solar PV. We find that over 8,000 companies have installed at least one residential PV system, with about 2,900 companies active in 2016. The majority of residential PV installers are relatively small companies, with about half of installers installing fewer than five systems. At the same time, a subset of high-volume installers accumulated market share, especially beginning aroundmore » 2010 with the emergence of alternative customer financing options.« less

Continued Development of the Solar System Concept Inventory

NASA Astrophysics Data System (ADS)

Hornstein, Seth D.; Prather, E. E.; English, T. R.; Desch, S. M.; Keller, J. M.; CATS

2010-01-01

The Solar System Concept Inventory (SSCI) was developed in order to provide a pre-/post-instruction assessment instrument suitable for use in an introductory solar system course. The topics included on the SSCI focus on formation mechanisms, planetary interiors, atmospheric and surface effects, and small solar system bodies. These topics were selected by having faculty identify the key concepts they address when teaching about the solar system. Student interviews were then conducted to identify common naive ideas and reasoning difficulties relating to these key topics. As of December 2009, the SSCI has been through four semesters of both pre- and post-instruction classroom testing, involving over 2000 students and 11 institutions (ranging from two-year colleges to doctoral/research universities). After each semester of testing, item analysis statistics such as point biserial, percentage correct on pre- or post-testing, and frequently-chosen distracters (incorrect answers) were used to flag ineffective questions. Flagged questions were revised or eliminated. We present an overall outline of the SSCI development as well as our question-flagging criteria and question analyses from the latest round of field-testing. We would like to thank the NSF for funding under Grant No. 0715517, a CCLI Phase III Grant for the Collaboration of Astronomy Teaching Scholars (CATS) Program.

Energy Systems Integration News | Energy Systems Integration Facility |

Science.gov Websites

hierarchical control architecture that enables a hybrid control approach, where centralized control systems will be complemented by distributed control algorithms for solar inverters and autonomous control of ), involves developing a novel control scheme that provides system-wide monitoring and control using a small

The 1.5 meter solar telescope GREGOR

NASA Astrophysics Data System (ADS)

Schmidt, W.; von der Lühe, O.; Volkmer, R.; Denker, C.; Solanki, S. K.; Balthasar, H.; Bello Gonzalez, N.; Berkefeld, Th.; Collados, M.; Fischer, A.; Halbgewachs, C.; Heidecke, F.; Hofmann, A.; Kneer, F.; Lagg, A.; Nicklas, H.; Popow, E.; Puschmann, K. G.; Schmidt, D.; Sigwarth, M.; Sobotka, M.; Soltau, D.; Staude, J.; Strassmeier, K. G.; Waldmann , T. A.

2012-11-01

The 1.5 m telescope GREGOR opens a new window to the understanding of solar small-scale magnetism. The first light instrumentation includes the Gregor Fabry Pérot Interferometer (GFPI), a filter spectro-polarimeter for the visible wavelength range, the GRating Infrared Spectro-polarimeter (GRIS) and the Broad-Band Imager (BBI). The excellent performance of the first two instruments has already been demonstrated at the Vacuum Tower Telescope. GREGOR is Europe's largest solar telescope and number 3 in the world. Its all-reflective Gregory design provides a large wavelength coverage from the near UV up to at least 5 microns. The field of view has a diameter of 150 arcsec. GREGOR is equipped with a high-order adaptive optics system, with a subaperture size of 10 cm, and a deformable mirror with 256 actuators. The science goals are focused on, but not limited to, solar magnetism. GREGOR allows us to measure the emergence and disappearance of magnetic flux at the solar surface at spatial scales well below 100 km. Thanks to its spectro-polarimetric capabilities, GREGOR will measure the interaction between the plasma flows, different kinds of waves, and the magnetic field. This will foster our understanding of the processes that heat the chromosphere and the outer layers of the solar atmosphere. Observations of the surface magnetic field at very small spatial scales will shed light on the variability of the solar brightness.

The future of stellar occultations by distant solar system bodies: Perspectives from the Gaia astrometry and the deep sky surveys

NASA Astrophysics Data System (ADS)

Camargo, J. I. B.; Desmars, J.; Braga-Ribas, F.; Vieira-Martins, R.; Assafin, M.; Sicardy, B.; Bérard, D.; Benedetti-Rossi, G.

2018-05-01

Distant objects in the solar system are crucial to better understand the history and evolution of its outskirts. The stellar occultation technique allows the determination of their sizes and shapes with kilometric accuracy, a detailed investigation of their immediate vicinities, as well as the detection of tenuous atmospheres. The prediction of such events is a key point in this study, and yet accurate enough predictions are available to a handful of objects only. In this work, we briefly discuss the dramatic impact that both the astrometry from the Gaia space mission and the deep sky surveys - the Large Synoptic Survey Telescope in particular - will have on the prediction of stellar occultations and how they may influence the future of the study of distant small solar system bodies through this technique.

Solar System Studies in the Infrared with the Spitzer Space Telescope

NASA Technical Reports Server (NTRS)

Cruikshank, D. P.; Stansberry, J. A.; Cleve, J. Van; Burgdorf, M. J.; Fernandez, Y. R.; Meadows, V. S.; Reach, W. T.

2004-01-01

The Spitzer Space Telescope, formerly known as SIRTF, is a cryogenic telescope (85 cm diameter) operating in a heliocentric orbit trailing the Earth. Its three instruments provide capabilities for spectroscopy, wide-field and small-field imaging at many wavelengths in the range 3.5-160 microns. Observations to be executed in the first two years in programs defined by the Guaranteed Time Observer (GTO) group (the authors of this presentation) consist of photometry, spectroscopy, and radiometry of many Solar System objects, including Titan and other satellites of the outer planets, Pluto, Centaurs, trans-Neptunian objects, comers, asteroids, Uranus, and Neptune. At the time of the preparation of this abstract, some preliminary observations have been made, but the final calibration and reduction of the data are still in progress. The latest results of the Solar System investigations will be presented here.

Can The Periods of Some Extra-Solar Planetary Systems be Quantized?

NASA Astrophysics Data System (ADS)

El Fady Morcos, Abd

A simple formula was derived before by Morcos (2013 ), to relate the quantum numbers of planetary systems and their periods. This formula is applicable perfectly for the solar system planets, and some extra-solar planets , of stars of approximately the same masses like the Sun. This formula has been used to estimate the periods of some extra-solar planet of known quantum numbers. The used quantum numbers were calculated previously by other authors. A comparison between the observed and estimated periods, from the given formula has been done. The differences between the observed and calculated periods for the extra-solar systems have been calculated and tabulated. It is found that there is an error of the range of 10% The same formula has been also used to find the quantum numbers, of some known periods, exo-planet. Keywords: Quantization; Periods; Extra-Planetary; Extra-Solar Planet REFERENCES [1] Agnese, A. G. and Festa, R. “Discretization on the Cosmic Scale Inspirred from the Old Quantum Mechanics,” 1998. http://arxiv.org/abs/astro-ph/9807186 [2] Agnese, A. G. and Festa, R. “Discretizing ups-Andro- medae Planetary System,” 1999. http://arxiv.org/abs/astro-ph/9910534. [3] Barnothy, J. M. “The Stability of the Solar Systemand of Small Stellar Systems,” Proceedings of the IAU Sympo-sium 62, Warsaw, 5-8 September 1973, pp. 23-31. [4] Morcos, A.B. , “Confrontation between Quantized Periods of Some Extra-Solar Planetary Systems and Observations”, International Journal of Astronomy and Astrophysics, 2013, 3, 28-32. [5] Nottale, L. “Fractal Space-Time and Microphysics, To-wards a Theory of Scale Relativity,” World Scientific, London, 1994. [6] Nottale , L., “Scale-Relativity and Quantization of Extra- Solar Planetary Systems,” Astronomy & Astrophysics, Vol. 315, 1996, pp. L9-L12 [7] Nottale, L., Schumacher, G. and Gay, J. “Scale-Relativity and Quantization of the Solar Systems,” Astronomy & Astrophysics letters, Vol. 322, 1997, pp. 1018-10 [8]Nottale, L. “Scale-Relativity and Quantization of Exo- planet Orbital Semi-Major Axes,” Astronomy & Astro- physics, Vol. 361, 2000, pp. 379-387.

Development of the Solar System Concept Inventory

NASA Astrophysics Data System (ADS)

Hornstein, S.; Prather, E.

2009-12-01

Concept inventories can provide useful insight into students’ understanding of key physical concepts. Knowing what your students have learned during a course is a valuable tool for improving your own teaching. Unfortunately, current astronomy concept inventories are not suitable for an introductory solar system course because they either cover too broad of a range of topics (e.g. Astronomy Diagnostic Test) or are too narrowly focused (e.g. Greenhouse Effect Concept Inventory, Lunar Phase Concept Inventory). We have developed the Solar System Concept Inventory (SSCI) to cover those topics commonly taught in an introductory solar system course. The topics included on the SSCI were selected by having faculty identify the key concepts they address when teaching about the solar system. SSCI topics include formation mechanisms, planetary interiors, atmospheric effects, and small solar system bodies. Student interviews were conducted to identify common naive ideas and reasoning difficulties relating to these key topics. The SSCI has been through two semesters of national, multi-institutional field-testing, involving over 1500 students. After the first semester of testing, question statistics were used to flag ineffective questions and flagged questions were revised or eliminated. We will present an overall outline of the SSCI development as well as our question-flagging criteria and question analyses from the latest round of field-testing. We would like to thank the NSF for funding under Grant No. 0715517, a CCLI Phase III Grant for the Collaboration of Astronomy Teaching Scholars (CATS) Program.

A New Way that Planets can Affect the Sun

NASA Technical Reports Server (NTRS)

Wolff, Charles; Patrone, Paul

2010-01-01

As planets orbit the Sun, the Sun also has to move to keep the total momentum of the solar system constant. The Sun's small orbital motion plus its 25 day rotation about its axis combine to invigorate some solar instabilities. Occasional convection cells at the proper phase in their short life can be strengthened by factors of two or more. This local burst of extra kinetic energy eventually reaches the surface where it can increase the intensity of solar activity. It might explain some reports in the last century of how planetary positions correlate with solar activity. This is the first effect of planets that is large enough to cause a significant response on the Sun.

Design and evaluation of a wing with embedded payloads for Small Unmanned Aerial System (SUAS) applications

NASA Astrophysics Data System (ADS)

Pearson, Roger A.

Rapidly advancing technology has developed multiple thin filmed devices capable of expanding the abilities of Small Unmanned Aircraft Systems (SUAS). This research develops a viable solution for integrating thin film solar cells into a currently operational SUAS. A wing was designed and produced that was capable of replacing the existing wing while providing additional functionality with embedded solar arrays. The study investigates the challenges of meeting the original requirements of the original equipment manufacturer wing while adapting it to fully protect and support structurally embedded payloads. In total, seven complete wings were produced and tested. Combinations of functional and simulated payloads were fully integrated into two of these wings. The merits of these designs were quantified and validated through both ground testing and flight testing with the SUAS.

Using Residential Solar PV Quote Data to Analyze the Relationship Between Installer Pricing and Firm Size

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

O'Shaughnessy, Eric; Margolis, Robert

2017-04-01

The vast majority of U.S. residential solar PV installers are small local-scale companies, however the industry is relatively concentrated in a few large national-scale installers. We develop a novel approach using solar PV quote data to study the price behavior of large solar PV installers in the United States. Through a paired differences approach, we find that large installer quotes are about higher, on average, than non-large installer quotes made to the same customer. The difference is statistically significant and robust after controlling for factors such as system size, equipment quality, and time effects. The results suggest that low pricesmore » are not the primary value proposition of large installer systems. We explore several hypotheses for this finding, including that large installers are able to exercise some market power and/or earn returns from reputations.« less

TRAPPIST-1 Comparison to Solar System and Jovian Moons

NASA Image and Video Library

2017-02-22

All seven planets discovered in orbit around the red dwarf star TRAPPIST-1 could easily fit inside the orbit of Mercury, the innermost planet of our solar system. In fact, they would have room to spare. TRAPPIST-1 also is only a fraction of the size of our sun; it isn't much larger than Jupiter. So the TRAPPIST-1 system's proportions look more like Jupiter and its moons than those of our solar system. The seven planets of TRAPPIST-1 are all Earth-sized and terrestrial, according to research published in 2017 in the journal Nature. TRAPPIST-1 is an ultra-cool dwarf star in the constellation Aquarius, and its planets orbit very close to it. The system has been revealed through observations from NASA's Spitzer Space Telescope and the ground-based TRAPPIST (TRAnsiting Planets and PlanetesImals Small Telescope) telescope, as well as other ground-based observatories. The system was named for the TRAPPIST telescope. http://photojournal.jpl.nasa.gov/catalog/PIA21428

The Discovery of Extrasolar Planets by Backyard Astronomers

NASA Technical Reports Server (NTRS)

Castellano, Tim; Laughlin, Greg; DeVincenzi, D. (Technical Monitor)

2002-01-01

The discovery since 1995 of more than 80 planets around nearby solar-like stars and the photometric measurement of a transit of the jovian mass planet orbiting the solar-like star HD 209458 (producing a more than 1% drop in brightness that lasts 3 hours) has heralded a new era in astronomy. It has now been demonstrated that small telescopes equipped with sensitive and stable electronic detectors can produce fundamental scientific discoveries regarding the frequency and nature of planets outside the solar system. The modest equipment requirements for the discovery of extrasolar planetary transits of jovian mass planets in short period orbits around solar-like stars are fulfilled by commercial small aperture telescopes and CCD (charge coupled device) imagers common among amateur astronomers. With equipment already in hand and armed with target lists, observing techniques and software procedures developed by scientists at NASA's Ames Research Center and the University of California at Santa Cruz, non-professional astronomers can contribute significantly to the discovery and study of planets around others stars. In this way, we may resume (after a two century interruption!) the tradition of planet discoveries by amateur astronomers begun with William Herschel's 1787 discovery of the 'solar' planet Uranus.

Dynamic mass exchange in doubly degenerate binaries. I - 0.9 and 1.2 solar mass stars

NASA Technical Reports Server (NTRS)

Benz, W.; Cameron, A. G. W.; Press, W. H.; Bowers, R. L.

1990-01-01

The dynamic mass exchange process in doubly degenerate binaries was investigated using a three-dimensional numerical simulation of the evolution of a doubly degenerate binary system in which the primary is a 1.2-solar-mass white dwarf and the Roche lobe filling secondary is a 0.9-solar-mass dwarf. The results show that, in a little more than two orbital periods, the secondary is completely destroyed and transformed into a thick disk orbiting about the primary. Since only a very small fraction of the mass (0.0063 solar mass) escapes the system, the evolution of the binary results in the formation of a massive object. This object is composed of three parts, the initial white dwarf primary, a very hot pressure-supported spherical envelope, and a rotationally supported outer disk. The evolution of the system can be understood in terms of a simple analytical model where it is shown that the angular momentum carried by the mass during the transfer and stored in the disk determines the evolution of the system.

Thermal Development Test of the NEXT PM1 ION Engine

NASA Technical Reports Server (NTRS)

Anderson, John R.; Snyder, John Steven; Van Noord, Jonathan L.; Soulas, George C.

2007-01-01

NASA's Evolutionary Xenon Thruster (NEXT) is a next-generation high-power ion thruster under development by NASA as a part of the In-Space Propulsion Technology Program. NEXT is designed for use on robotic exploration missions of the solar system using solar electric power. Potential mission destinations that could benefit from a NEXT Solar Electric Propulsion (SEP) system include inner planets, small bodies, and outer planets and their moons. This range of robotic exploration missions generally calls for ion propulsion systems with deep throttling capability and system input power ranging from 0.6 to 25 kW, as referenced to solar array output at 1 Astronomical Unit (AU). Thermal development testing of the NEXT prototype model 1 (PM1) was conducted at JPL to assist in developing and validating a thruster thermal model and assessing the thermal design margins. NEXT PM1 performance prior to, during and subsequent to thermal testing are presented. Test results are compared to the predicted hot and cold environments expected missions and the functionality of the thruster for these missions is discussed.

Sputtering of ices in the outer solar system

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

Johnson, R.E.

1996-01-01

Exploration of the outer solar system has led to studies in a new area of physics: electronically induced sputtering of low-temperature, condensed-gas solids (ices). Many of the icy bodies in the outer solar system were found to be bombarded by relatively intense fluxes of ions and electrons, causing both changes in their optical reflectance and ejection (sputtering) of molecules from their surfaces. The small cohesive energies of the condensed-gas solids afford relatively large sputtering rates from the electronic excitations produced in the solid by fast ions and electrons. Such sputtering produces an ambient gas about an icy body, often themore » source of the local plasma. This colloquium outlines the physics of the sputtering of ices and its relevance to several outer-solar-system phenomena: the sputter-produced plasma trapped in Saturn{close_quote}s magnetosphere; the O{sub 2} atmosphere on Europa; and optical absorption features such as SO{sub 2} in the surface of Europa and O{sub 2} and, possibly, O{sub 3} in the surface of Ganymede. {copyright} {ital 1996 The American Physical Society.}« less

Conformal Electroplating of Azobenzene-Based Solar Thermal Fuels onto Large-Area and Fiber Geometries.

PubMed

Zhitomirsky, David; Grossman, Jeffrey C

2016-10-05

There is tremendous growth in fields where small functional molecules and colloidal nanomaterials are integrated into thin films for solid-state device applications. Many of these materials are synthesized in solution and there often exists a significant barrier to transition them into the solid state in an efficient manner. Here, we develop a methodology employing an electrodepositable copolymer consisting of small functional molecules for applications in solar energy harvesting and storage. We employ azobenzene solar thermal fuel polymers and functionalize them to enable deposition from low concentration solutions in methanol, resulting in uniform and large-area thin films. This approach enables conformal deposition on a variety of conducting substrates that can be either flat or structured depending on the application. Our approach further enables control over film growth via electrodepsition conditions and results in highly uniform films of hundreds of nanometers to microns in thickness. We demonstrate that this method enables superior retention of solar thermal fuel properties, with energy densities of ∼90 J/g, chargeability in the solid state, and exceptional materials utilization compared to other solid-state processing approaches. This novel approach is applicable to systems such as photon upconversion, photovoltaics, photosensing, light emission, and beyond, where small functional molecules enable solid-state applications.

Temperature Response of Emissivity in Intrinsic Silicon: A Selective Absorber for Solar Energy Harvesting

NASA Astrophysics Data System (ADS)

Heredia, Cristian Alonso

The National Academy of Engineers named affordable solar energy as one of the grand challenges for the twenty-first century. Even in sunniest U.S. locations, without subsidies, home generation is still cost prohibitive. To address the cost of solar energy, we investigated intrinsic silicon as a low emissivity selective absorber. We wanted to determine the emissivity of intrinsic silicon at elevated temperatures. At elevated temperatures, a selective absorber coupled to a heat engine could efficiently generate electrical power. Photothermal efficiency depends on the absorber's emissivity. I analyzed total hemispherical emissivity for graphite and intrinsic silicon using a thermal decay method inside a thermal isolation chamber. The results show low emissivity values for intrinsic silicon. Consequently, for temperatures less than 300 °C, intrinsic silicon has a small emissivity (0.16). This small value is in agreement with doped silicon experiments. However, unlike doped silicon, at elevated temperatures of 600 °C, intrinsic silicon emissivity values remain low (0.33). Our analysis suggests intrinsic silicon could convert more solar power into heat than an ideal blackbody. Specifically, the harvested heat could drive a heat engine for efficient power generation. Thus, a cost-effective electrical generating system can operate with a small land footprint using earth abundant silicon.

The use of solar energy - photovoltaic - in hydrogen production and arid zones like Saudi Arabia

NASA Astrophysics Data System (ADS)

Sayigh, A. A. M.

This paper deals with the use of photovoltaic technology for the production of hydrogen from water by electrolysis. First of all the amount of electricity needed for this process was assessed, then various types of solar cell systems to generate the electricity needed were discussed and the best system was established. Some of the investigations involved testing of solar cells with concentrators and with fixed tilt or tracking devices. Several small panels of solar cells were used in testing the effect of local dust and sand as well as the fixed tilt in the area of Riyadh. The cost of producing hydrogen by electrolysis using electricity from a conventional grid was calculated. This cost was compared with the cost of production of hydrogen if a solar cell array was used. The paper outlines the continuous price increase of oil to produce electricity and the rapid decrease in price of solar cells. Both these advances will lead to a cheaper way of producing hydrogen by solar energy. In addition it is shown that technology is almost trouble free and requires very little know-how as far as operation is concerned.

Wavelength Dependence of Solar Flare Irradiation and its Influence on the Thermosphere

NASA Technical Reports Server (NTRS)

Huang, Yanshi; Richmond, Arthur D.; Deng, Yue; Qian, L.; Solomon, S.; Chamberlin, P.

2012-01-01

The wavelength dependence of solar flare enhancement is one of the important factors determining how the Thermosphere-Ionosphere (T-I) system response to flares. To investigate the wavelength dependence of solar flare, the Flare Irradiance Spectral Model (FISM) has been run for 34 X-class flares. The results show that the percentage increases of solar irradiance at flare peak comparing to pre-flare condition have a clear wavelength dependence. In the wavelength range between 0 - 195 nm, it can vary from 1% to 10000%. The solar irradiance enhancement is largest ( 1000%) in the XUV range (0 - 25 nm), and is about 100% in EUV range (25 - 120 nm). The influence of different wavebands on the T-I system during the October 28th, 2003 flare (X17.2-class) has also been examined using the latest version of National Center for Atmospheric Research (NCAR) Thermosphere- Ionosphere-Electrodynamics General Circulation Model (TIE-GCM). While the globally integrated solar energy deposition is largest in the 0 - 14 nm waveband, the impact of solar irradiance enhancement on the thermosphere at 400 km is largest for 25 - 105 nm waveband. The effect of 122 - 195 nm is small in magnitude, but it decays slowly.

Theoretical studies of massive stars. II - Evolution of a 15 solar-mass star from carbon shell burning to iron core collapse

NASA Technical Reports Server (NTRS)

Sparks, W. M.; Endal, A. S.

1980-01-01

The evolution of a Population I star of 15 solar masses is described from the carbon shell burning stage to the formation and collapse of an iron core. An unusual aspect of the evolution is that neon ignition occurs off-center and neon burning propagates inward by a series of shell flashes. The extent of the core burning is generally smaller than the Chandrasekhar mass, so that most of the nuclear energy generation occurs in shell sources. Because of degeneracy and the influence of rapid convective mixing, these shell sources are unstable and the core goes through large excursions in temperature and density. The small core also causes the shell sources to converge into a narrow mass region slightly above the Chandrasekhar mass. Thus, the final nucleosynthesis yields are generally small, with silicon being most strongly enhanced with respect to solar system abundances.

Improving the Charge Carrier Transport and Suppressing Recombination of Soluble Squaraine-Based Solar Cells via Parallel-Like Structure

PubMed Central

Zhu, Youqin; Liu, Jingli; Zhao, Jiao; Li, Yang; Qiao, Bo; Song, Dandan; Huang, Yan; Xu, Zheng; Zhao, Suling; Xu, Xurong

2018-01-01

Small molecule organic solar cells (SMOSCs) have attracted extensive attention in recent years. Squaraine (SQ) is a kind of small molecule material for potential use in high-efficiency devices, because of its high extinction coefficient and low-cost synthesis. However, the charge carrier mobility of SQ-based film is much lower than other effective materials, which leads to the pretty low fill factor (FF). In this study, we improve the performance of SQ derivative-based solar cells by incorporating PCDTBT into LQ-51/PC71BM host binary blend film. The incorporation of PCDTBT can not only increase the photon harvesting, but also provide an additional hole transport pathway. Through the charge carrier mobility and transient photovoltage measurement, we find that the hole mobility and charge carrier lifetime increase in the ternary system. Also, we carefully demonstrate that the charge carrier transport follows a parallel-like behavior. PMID:29747394

The effect of concentrator field layout on the EE-1 small community solar power system

NASA Technical Reports Server (NTRS)

Pons, R. L.; Irwin, R. E.

1981-01-01

The point-focusing distributed receiver (PFDR) concept is employed by a number of solar thermal power systems currently under development. One type of PFDR system which shows particular promise incorporates distributed energy generation. According to this concept each parabolic dish collector is a self-contained power generation module, and a conventional electrical system is used to interconnect the modules. The concept is thus modular, and any number of power modules can be combined to achieve the required plant size. Given the benefits of mass production, it appears that this type of system can produce electricity at lower cost than is projected for conventional (fossil) power systems over the next decade. An employment of organic Rankine cycle heat engines is considered.

The effect of solar array degradation on electric propulsion spacecraft performance.

NASA Technical Reports Server (NTRS)

Sauer, C. G., Jr.; Bourke, R. D.

1972-01-01

Current estimates of solar-electric-propulsion spacecraft performance are based upon a solar-array output power which is degraded by approximately 10-13% to account for possible losses caused by proton, electron and micrometeorite damage. Past studies have used a worst case analysis in which the maximum degradation was taken to occur at the beginning of the mission. This paper presents a comparison of mission studies using a hypothetical exponential decrease in power with time, with those using a sudden degradation of solar power. These comparisons indicate that the performance gain by using a time varying degradation during the mission is quite small for outbound missions in the solar system. In addition an indication of the power allocation strategy to be followed during a mission is presented.

Strategies on solar observation of Atacama Large Millimeter/submillimeter Array (ALMA) band-1 receiver

NASA Astrophysics Data System (ADS)

Chiong, Chau-Ching; Chiang, Po-Han; Hwang, Yuh-Jing; Huang, Yau-De

2016-07-01

ALMA covering 35-950 GHz is the largest existing telescope array in the world. Among the 10 receiver bands, Band-1, which covers 35-50 GHz, is the lowest. Due to its small dimension and its time-variant frequency-dependent gain characteristics, current solar filter located above the cryostat cannot be applied to Band-1 for solar observation. Here we thus adopt new strategies to fulfill the goals. Thanks to the flexible dc biasing scheme of the HEMT-based amplifier in Band-1 front-end, bias adjustment of the cryogenic low noise amplifier is investigated to accomplish solar observation without using solar filter. Large power handling range can be achieved by the de-tuning bias technique with little degradation in system performance.

Maximizing the Scientific Return of Low Cost Planetary Missions Using Solar Electric Propulsion(abstract)

NASA Technical Reports Server (NTRS)

Russell, C. T.; Metzger, A.; Pieters, C.; Elphic, R. C.; McCord, T.; Head, J.; Abshire, J.; Philips, R.; Sykes, M.; A'Hearn, M.;

Astrochemical evolution along star formation: Overview of the IRAM Large Program ASAI

NASA Astrophysics Data System (ADS)

Lefloch, Bertrand; Bachiller, R.; Ceccarelli, C.; Cernicharo, J.; Codella, C.; Fuente, A.; Kahane, C.; López-Sepulcre, A.; Tafalla, M.; Vastel, C.; Caux, E.; González-García, M.; Bianchi, E.; Gómez-Ruiz, A.; Holdship, J.; Mendoza, E.; Ospina-Zamudio, J.; Podio, L.; Quénard, D.; Roueff, E.; Sakai, N.; Viti, S.; Yamamoto, S.; Yoshida, K.; Favre, C.; Monfredini, T.; Quitián-Lara, H. M.; Marcelino, N.; Roberty, H. Boechat; Cabrit, S.

2018-04-01

Evidence is mounting that the small bodies of our Solar System, such as comets and asteroids, have at least partially inherited their chemical composition from the first phases of the Solar System formation. It then appears that the molecular complexity of these small bodies is most likely related to the earliest stages of star formation. It is therefore important to characterize and to understand how the chemical evolution changes with solar-type protostellar evolution. We present here the Large Program "Astrochemical Surveys At IRAM" (ASAI). Its goal is to carry out unbiased millimeter line surveys between 80 and 272 GHz of a sample of ten template sources, which fully cover the first stages of the formation process of solar-type stars, from prestellar cores to the late protostellar phase. In this article, we present an overview of the surveys and results obtained from the analysis of the 3 mm band observations. The number of detected main isotopic species barely varies with the evolutionary stage and is found to be very similar to that of massive star-forming regions. The molecular content in O- and C- bearing species allows us to define two chemical classes of envelopes, whose composition is dominated by either a) a rich content in O-rich complex organic molecules, associated with hot corino sources, or b) a rich content in hydrocarbons, typical of Warm Carbon Chain Chemistry sources. Overall, a high chemical richness is found to be present already in the initial phases of solar-type star formation.

Radiation heat transfer simulation in a window for a small particle solar receiver using the Monte Carlo method

NASA Astrophysics Data System (ADS)

Whitmore, Alexander Jason

Concentrating solar power systems are currently the predominant solar power technology for generating electricity at the utility scale. The central receiver system, which is a concentrating solar power system, uses a field of mirrors to concentrate solar radiation onto a receiver where a working fluid is heated to drive a turbine. Current central receiver systems operate on a Rankine cycle, which has a large demand for cooling water. This demand for water presents a challenge for the current central receiver systems as the ideal locations for solar power plants have arid climates. An alternative to the current receiver technology is the small particle receiver. The small particle receiver has the potential to produce working fluid temperatures suitable for use in a Brayton cycle which can be more efficient when pressurized to 0.5 MPa. Using a fused quartz window allows solar energy into the receiver while maintaining a pressurized small particle receiver. In this thesis, a detailed numerical investigation for a spectral, three dimensional, cylindrical glass window for a small particle receiver was performed. The window is 1.7 meters in diameter and 0.0254 meters thick. There are three Monte Carlo Ray Trace codes used within this research. The first MCRT code, MIRVAL, was developed by Sandia National Laboratory and modified by a fellow San Diego State University colleague Murat Mecit. This code produces the solar rays on the exterior surface of the window. The second MCRT code was developed by Steve Ruther and Pablo Del Campo. This code models the small particle receiver, which creates the infrared spectral direction flux on the interior surface of the window used in this work. The third MCRT, developed for this work, is used to model radiation heat transfer within the window itself and is coupled to an energy equation solver to produce a temperature distribution. The MCRT program provides a source term to the energy equation. This in turn, produces a new temperature field for the MCRT program; together the equations are solved iteratively. These iterations repeat until convergence is reached for a steady state temperature field. The energy equation was solved using a finite volume method. The window's thermal conductivity is modeled as a function of temperature. This thermal model is used to investigate the effects of different materials, receiver geometries, interior convection coefficients and exterior convection coefficients. To prevent devitrification and the ultimate failure of the window, the window needs to stay below the devitrification temperature of the material. In addition, the temperature gradients within the window need to be kept to a minimum to prevent thermal stresses. A San Diego State University colleague E-Fann Saung uses these temperature maps to insure that the mounting of the window does not produce thermal stresses which can cause cracking in the brittle fused quartz. The simulations in this thesis show that window temperatures are below the devitrification temperature of the window when there are cooling jets on both surfaces of the window. Natural convection on the exterior window surface was explored and it does not provide adequate cooling; therefore forced convection is required. Due to the low thermal conductivity of the window, the edge mounting thermal boundary condition has little effect on the maximum temperature of the window. The simulations also showed that the solar input flux absorbed less than 1% of the incoming radiation while the window absorbed closer to 20% of the infrared radiation emitted by the receiver. The main source of absorbed power in the window is located directly on the interior surface of the window where the infrared radiation is absorbed. The geometry of the receiver has a large impact on the amount of emitted power which reached the interior surface of the window, and using a conical shaped receiver dramatically reduced the receiver's infrared flux on the window. The importance of internal emission is explored within this research. Internal emission produces a more even emission field throughout the receiver than applying radiation surface emission only. Due to a majority of the infrared receiver re-radiation being absorbed right at the interior surface, the surface emission only approximation method produces lower maximum temperatures.

Tholins as Coloring Agents on Solar System Bodies

NASA Technical Reports Server (NTRS)

Cruikshank, D. P.; Ore, C. M. Dalle; Imanaka, H.

2004-01-01

Pre-biotic organic materials appear to be common on many small bodies in the outer Solar System, as evidenced by the color properties of these objects. We report on our continuing study of color properties in connection with the presence of complex organic solids (tholins) among the planets and their satellites, the asteroids, and the trans- Neptunian objects (Kuiper Belt objects). Most small, icy bodies in the Solar System, whether they have high or low surface reflectance (albedo), show a pronounced downward slope in reflectance at wavelengths shorter than approx. 1 micron. This increasing absorption of sunlight toward shorter wavelengths is characteristic of pi-bonds in hydrocarbons having chains or rings of conjugated C atoms. Tholins, which contain polycyclic aromatic and aliphatic hydrocarbons, exhibit these color properties. Using the complex refractive indices of tholins in models of the reflectance spectra of icy bodies in the Solar System, we find that these complex organic materials satisfactorily account for the coloration so widely observed. The new results presented here show that the wide variety of colors of Kuiper Belt objects can be fit very well with tholins, as can the colors of Pluto and Triton. The implications of these fits of Kuiper Belt objects is that complex organic material is created on their surfaces by energetic particle bombardment of native ices, and also may be accreted from external sources. In the cases of Pluto and Triton, photochemistry of their weak N2 + CH4 + CO atmospheres produces complex organic molecules that precipitate to the surface, providing local color.

A solar thermal electric power plant for small communities

NASA Technical Reports Server (NTRS)

Holl, R. J.

1979-01-01

A solar power plant has been designed with a rating of 1000-kW electric and a 0.4 annual capacity factor. It was configured as a prototype for plants in the 1000 to 10,000-kWe size range for application to small communities or industrial users either grid-connected or isolated from a utility grid. A small central receiver was selected for solar energy collection after being compared with alternative distributed collectors. Further trade studies resulted in the selection of Hitec (heat transfer salt composed of 53 percent KNO3, 40 percent NaNO2, 7 percent NaNO3) as both the receiver coolant and the sensible heat thermal stroage medium and the steam Rankine cycle for power conversion. The plant is configured with road-transportable units to accommodate remote sites and minimize site assembly requirements. Results of the analyses indicate that busbar energy costs are competitive with diesel-electric plants in certain situations, e.g., off-grid, remote regions with high insolation. Sensitivity of energy costs to plant power rating and system capacity factor are given.

The Development of Small Solar Concentrating Systems with Heat Storage for Rural Food Preparation

NASA Astrophysics Data System (ADS)

van den Heetkamp, R. R. J.

A system, consisting of a parabolic reflector mounted on a polar axis tracker, has been designed and built. Air at atmospheric pressure is heated by the concentrated solar radiation to temperatures of up to 400°C as it is sucked through the receiver and into the pebble-bed heat storage unit, by means of a fan at the bottom of the storage. The stored heat is recovered by the reversal of the fan and the resulting hot air can be used in a convection oven and other appliances. This report discusses practical aspects, as well as preliminary test results, of such a system.

Development of Surfaces Optically Suitable for Flat Solar Panels

NASA Technical Reports Server (NTRS)

Desmet, D.; Jason, A.

1978-01-01

Three areas of research in the development of flat solar panels are described. (1) A reflectometer which can separately evaluate the spectral and diffuse reflectivities of surfaces was developed. The reflectometer has a phase locked detection system. (2) A coating composed of strongly bound copper oxide that is formed by an etching process performed on an aluminum alloy with high copper content was also developed. Because of this one step fabrication process, fabrication costs are expected to be small. (3) A literature search was conducted and conclusions on the required optical properties of flat plate solar collectors are presented.

Volatiles Delivery to the Terrestrial Planets

NASA Astrophysics Data System (ADS)

Marov, M. Ya.; Ipatov, S. I.

2006-08-01

Migration of small bodies and dust particles from the outer regions of the solar system is an important mechanism of the formation and evolution of atmospheres and hydrospheres of the terrestrial planets [1]. It is assumed that these bodies and particles could be responsible for the delivery of the original matter (mainly volatiles) and thus could give rise to the life origin. A fraction of dust particles migrated inward solar system is believed to be of interstellar origin embedded in presolar nebula and preserved for a long time at the fringe of the solar system. Our studies of volatiles delivery were based on results of numerical integration of the migration of small bodies and dust particles in the Solar System [2]. It was shown that the exogenous mechanism of heterogeneous accretion and the endogenous mechanism of the interior degassing may contribute to the formation of planetary atmospheres and hydrospheres at least comparably. If the total mass of planetesimals beyond Jupiter's orbit exceeded a hundred of Earth masses, then of the total mass of volatiles delivered to the Earth exceeded the amount of water in the Earth's oceans. The results of our studies of the migration of dust particles of various genesis lead to the conclusion that a portion of cometary and trans-Neptunian dust particles highly enriched by volatiles can be considerable among particles of other origin. Although it is difficult to obtain exact estimates of the dust influx to the Earth and neighboring planets, it was shown that, in comparison with small bodies, the dust contribution is 3-4 orders of magnitude smaller. However, dust particles could have been most efficient in the delivery of organic prebiogenic and, most likely, biogenic matter, because they are subjected to substantially weaker heating at the altitudes at which they enter the atmosphere and decelerate in it. This conclusion is confirmed by laboratory investigations into the probability of survival of bacteria and phages heated up to 200^o C and allows one to consider dust as a potential carrier of biogenic material from outer space. [1] Marov M. Ya. and Ipatov S.I., Solar System Research, 2005, 39, 374-380. [2] Ipatov S.I. and Mather J.C., Advances in Space Research, 2006, 37, 126-137.

Construction of a photovoltaic power system at Natural Bridges National Monument

NASA Astrophysics Data System (ADS)

Benoit, A. E.

1980-12-01

A 100 kW peak photovoltaic (PV) power system at Natural Bridges National Monument in Utah is described. This system is the largest of its kind in the world. The construction phases of the program are described, and a chronological history of the events and problems encountered when such a large and complex task is undertaken in a remote area with very limited fabrication facilities is given. This experiment demonstrates the application of solar energy to the variety of loads found in a small and remote community. This solar energy system was designed to meet all electrical requirements when there is no utility grid, with only occasional back-up from an existing diesel generator.

Revealing Exo-Zody and Exo-Planets from Solar System Dust Measurements: ALADDIN-2 for the Solar Power Sail Mission

NASA Astrophysics Data System (ADS)

Yano, Hajime; Hirai, Takayuki

2016-07-01

The dust structure of our Solar System provides a benchmark information of dust disks of other exo-planetary systems in general, just like the Sun as the closest main sequence G-star that we can study with the most details. Heliocentric dust distributions and gravitational and orbital interactions with planets such as mean motion resonances (MMRs) of dust flux of our Solar System are what we can transfer the knowledge of our Solar System dust apply to infer anisotropic exo-zodiacal brightness, or spatial structures within a exo-planetary dust disks with information about potentially embedded planets inside. In the coming era of disk resolved observations by ALMA, TMT and other new telescopes, we will be able to apply what we find in the Solar System to the rest of planetary systems. In 2010-11, the IKAROS solar sail spacecraft carried the ALADDIN large area dust detector array to study large meteoroids between the Earth and Venus orbits. Yano et al. directly detected both the Earth's and Venus' MMRs dust structures, being consistent with numerical simulations that predict the existence of such local enhancements of dust distribution around these terrestrial planets, as well as Neptune. JAXA's Solar Power Sail mission plans to carry even larger dust detector inherited the technology onboard IKAROS, namely ALADDIN-2 in order to search for such MMRs in the Mars and Jupiter orbits, as predicted by Kuchner et al.(2000), in addition to make a continuous measurement of large dust flux from 1.0 to 5.2 AU crossing the main asteroid belt up to Jupiter Trojan region. It is also noted that recent reanalysis of the Pioneer 10 and 11 photo polarimeter data suggests a small enhancement of the brightness towards the anti-solar direction near Jupiter the largest planet of our Solar System, implying a possible existence of a dust belt related to the planet. The spatial density of dust particles directly measured by the ALADDIN-2 will provide a more conclusive and direct proof due to the insusceptibility to the background brightness from the stars and the galaxy.

Jupiter Analogs Orbit Stars with an Average Metallicity Close to That of the Sun

NASA Astrophysics Data System (ADS)

Buchhave, Lars A.; Bitsch, Bertram; Johansen, Anders; Latham, David W.; Bizzarro, Martin; Bieryla, Allyson; Kipping, David M.

2018-03-01

Jupiter played an important role in determining the structure and configuration of the Solar System. Whereas hot-Jupiter type exoplanets preferentially form around metal-rich stars, the conditions required for the formation of planets with masses, orbits, and eccentricities comparable to Jupiter (Jupiter analogs) are unknown. Using spectroscopic metallicities, we show that stars hosting Jupiter analogs have an average metallicity close to solar, in contrast to their hot-Jupiter and eccentric cool-Jupiter counterparts, which orbit stars with super-solar metallicities. Furthermore, the eccentricities of Jupiter analogs increase with host-star metallicity, suggesting that planet–planet scatterings producing highly eccentric cool Jupiters could be more common in metal-rich environments. To investigate a possible explanation for these metallicity trends, we compare the observations to numerical simulations, which indicate that metal-rich stars typically form multiple Jupiters, leading to planet–planet interactions and, hence, a prevalence of either eccentric cool Jupiters or hot Jupiters with circularized orbits. Although the samples are small and exhibit variations in their metallicities, suggesting that numerous processes other than metallicity affect the formation of planetary systems, the data in hand suggests that Jupiter analogs and terrestrial-sized planets form around stars with average metallicities close to solar, whereas high-metallicity systems preferentially host eccentric cool Jupiter or hot Jupiters, indicating that higher metallicity systems may not be favorable for the formation of planetary systems akin to the Solar System.

Passive solar design strategies: Remodeling guidelines for conserving energy at home

NASA Astrophysics Data System (ADS)

The idea of passive solar is simple, but applying it effectively does require information and attention to the details of design and construction. Some passive solar techniques are modest and low-cost, and require only small changes in remodeler's typical practice. At the other end of the spectrum, some passive solar systems can almost eliminate a house's need for purchased heating (and in some cases, cooling) energy - but probably at a relatively high first cost. In between are a broad range of energy-conserving passive solar techniques. Whether or not they are cost-effective, practical, and attractive enough to offer a market advantage to any individual remodeler depends on very specific factors such as local costs, climate, and market characteristics. Passive Solar Design Strategies: Remodeling Guidelines For Conserving Energy At Home is written to help give remodelers the information they need to make these decisions. Passive Solar Design Strategies is a package in three basic parts: the guidelines contain information about passive solar techniques and how they work, and provides specific examples of systems which will save various percentages of energy; the worksheets offer a simple, fill-in-the-blank method to pre-evaluate the performance of a specific design; and the worked example demonstrates how to complete the worksheets for a typical residence.

Tracing the journey of the Sun and the Solar siblings through the Milky Way

NASA Astrophysics Data System (ADS)

Martínez-Barbosa, Carmen Adriana

2016-04-01

This thesis is focused on studying the motion of the Sun and the Solar siblings through the Galaxy. The Solar siblings are stars that were born with the Sun in the same molecular cloud 4.6 Gyr ago. In the first part of the thesis, we present an efficient method to calculate the evolution of small systems embedded in larger systems. Generalizations of this method are used to calculate the motion of the Sun and the Solar siblings in an analytical potential containing a central bar and spiral arms. By integrating the orbit of the Sun backwards in time, we determine its birth radius and the amount of radial migration experienced by our star. The birth radius of the Sun is used to investigate the evolution and disruption of the Sun's birth cluster. Depending on the Galaxy model parameters, the present-day phase-space distribution of the Solar siblings might be quite different. We used these data to predict the regions in the Galaxy where it will be more likely to search for So! lar siblings in the future. Finally, we compute the stellar encounters experienced by the Sun along its orbit and their role on the stability of the outer Solar System.

Solar and Drag Sail Propulsion: From Theory to Mission Implementation

NASA Technical Reports Server (NTRS)

Johnson, Les; Alhorn, Dean; Boudreaux, Mark; Casas, Joe; Stetson, Doug; Young, Roy

2014-01-01

Solar and drag sail technology is entering the mainstream for space propulsion applications within NASA and around the world. Solar sails derive propulsion by reflecting sunlight from a large, mirror- like sail made of a lightweight, reflective material. The continuous sunlight pressure provides efficient primary propulsion without the expenditure of propellant or any other consumable, allowing for very high V maneuvers and long-duration deep space exploration. Drag sails increase the aerodynamic drag on Low Earth Orbit (LEO) spacecraft, providing a lightweight and relatively inexpensive approach for end-of-life deorbit and reentry. Since NASA began investing in the technology in the late 1990's, significant progress has been made toward their demonstration and implementation in space. NASA's Marshall Space Flight Center (MSFC) managed the development and testing of two different 20-m solar sail systems and rigorously tested them under simulated space conditions in the Glenn Research Center's Space Power Facility at Plum Brook Station, Ohio. One of these systems, developed by L'Garde, Inc., is planned for flight in 2015. Called Sunjammer, the 38m sailcraft will unfurl in deep space and demonstrate solar sail propulsion and navigation as it flies to Earth-Sun L1. In the interim, NASA MSFC funded the NanoSail-D, a subscale drag sail system designed for small spacecraft applications. The NanoSail-D flew aboard the Fast Affordable Science and Technology SATellite (FASTSAT) in 2010, also developed by MSFC, and began its mission after it was was ejected from the FASTSAT into Earth orbit, where it remained for several weeks before deorbiting as planned. NASA recently selected two small satellite missions as part of the Advanced Exploration Systems (AES) Program, both of which will use solar sails to enable their scientific objectives. Lunar Flashlight, managed by JPL, will search for and map volatiles in permanently shadowed Lunar craters using a solar sail as a gigantic mirror to steer sunlight into the shaded craters. The Near Earth Asteroid (NEA) Scout mission will use the sail as primary propulsion allowing it to survey and image one or more NEA's of interest for possible future human exploration. Both are planned for launch in 2017. 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 rockets. For example, the NASA Heliophysics Decadal Survey identifies no less than three such missions for possible flight before the mid-2020's. Solar sail propulsion technology is no longer an intesting theoretical possibility; it has been demonstrated in space and is now a critical technology for science and solar system exploration.

Philippines: Small-scale renewable energy update

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

NONE

1997-12-01

This paper gives an overview of the application of small scale renewable energy sources in the Philippines. Sources looked at include solar, biomass, micro-hydroelectric, mini-hydroelectric, wind, mini-geothermal, and hybrid. A small power utilities group is being spun off the major utility, to provide a structure for developing rural electrification programs. In some instances, private companies have stepped forward, avoiding what is perceived as overwhelming beaurocracy, and installed systems with private financing. The paper provides information on survey work which has been done on resources, and the status of cooperative programs to develop renewable systems in the nation.

Evidence for extreme Ti-50 enrichments in primitive meteorites

NASA Technical Reports Server (NTRS)

Fahey, A.; Mckeegan, K. D.; Zinner, E.; Goswami, J. N.

1985-01-01

The results of the first high mass resolution ion microprobe study of Ti isotopic compositions in individual refractory grains from primitive carbonaceous meteorites are reported. One hibonite from the Murray carbonaceous chondrite has a 10 percent excess of Ti-50, 25 times higher than the maximum value previously reported for bulk samples of refractory inclusions from carbonaceous chondrites. The variation of the Ti compositions between different hibonite grains, and among pyroxenes from a single Allende refractory inclusion, indicates isotopic inhomogeneities over small scale lengths in the solar nebula and emphasizes the importance of the analysis of small individual phases. This heterogeneity makes it unlikely that the isotopic anomalies were carried into the solar system in the gas phase.

Chasing a Comet with a Solar Sail

NASA Technical Reports Server (NTRS)

Stough, Robert W.; Heaton, Andrew F.; Whorton, Mark S.

2008-01-01

Solar sail propulsion systems enable a wide range of missions that require constant thrust or high delta-V over long mission times. One particularly challenging mission type is a comet rendezvous mission. This paper presents optimal low-thrust trajectory designs for a range of sailcraft performance metrics and mission transit times that enables a comet rendezvous mission. These optimal trajectory results provide a trade space which can be parameterized in terms of mission duration and sailcraft performance parameters such that a design space for a small satellite comet chaser mission is identified. These results show that a feasible space exists for a small satellite to perform a comet chaser mission in a reasonable mission time.

Current Status of Carl Sagan Observatory in Mexico

NASA Astrophysics Data System (ADS)

Sanchez-Ibarra, A.

The current status of Observatory "Carl Sagan" (OCS) of University of Sonora is presented. This project was born in 1996 focused to build a small solar-stellar observatory completely operated by remote control. The observatory will be at "Cerro Azul", a 2480 m peak in one of the best regions in the world for astronomical observation, at the Sonora-Arizona desert. The OCS, with three 16 cm solar telescopes and a 55 cm stellar telescope is one of the cheapest observatories, valuated in US200,000 Added to its scientific goals to study solar coronal holes and Supernovae Type 1A, the OCS has a strong educative and cultural program in Astronomy to all levels. At the end of 2001, we started the Program "Constelacion", to build small planetariums through all the countries with a cost of only US80,000. Also, the webcast system for transmission of the solar observations from the prototype OCS at the campus, was expanded to webcast educational programs in Astronomy since July of this year, including courses and diplomats for Latin American people. All of these advances are exposed here.

On the Trojan asteroid sample and return mission via solar-power sail -- an innovative engineering demonstration

NASA Astrophysics Data System (ADS)

Kawaguchi, J.; Mori, O.; Shirasawa, Y.; Yoshikawa, M.

2014-07-01

The science and engineering communities in the world are seeking what comes next. Especially for asteroids and comets, as those objects lie in relatively far area in our solar system, and new engineering solutions are essential to explore them. JAXA has studied the next-step mission since 2000, a solar-power sail demonstrator combining the use of photon propulsion with electric propulsion, ion thruster, targeting the untrodden challenge for the sample return attempt from a Trojan asteroid around the libration points in the Sun-Jupiter system. The Ikaros spacecraft was literally developed and launched as a preliminary technology demonstration. The mission will perform in-situ measurement and on-site analysis of the samples in addition to the sample return to the Earth, and will also deploy a small lander on the surface for collecting surface samples and convey them to the mother spacecraft. From a scientific point of view, there is an enormous reward in the most primitive samples containing information about the ancient solar system and also about the origin of life in our solar system. JAXA presently looks for international partners to develop and build the lander. The presentation will elaborate the current mission scenario as well as what we think the international collaboration will be.

The effect of aerosols on the earth-atmosphere albedo

NASA Technical Reports Server (NTRS)

Herman, B. M.; Browning, S. R.

1975-01-01

The paper presents calculations of the change in reflected flux by the earth-atmosphere system in response to increases in the atmospheric aerosol loading for a range of complex indices of refraction, solar elevation angle and ground albedo. Results show that, for small values of ground albedo, the reflected solar flux may either increase or decrease with increasing aerosol loadings, depending upon the complex part of the index of refraction of the aerosols. For high ground albedos, an increase in aerosol levels always results in a decrease of reflected flux (i.e., a warming of the earth-atmosphere system).

Long-Term Dynamics of Small Bodies in the Solar System

NASA Technical Reports Server (NTRS)

Holman, Matthew J.; Grant, John (Technical Monitor)

2002-01-01

As part of the NASA Planetary Geology and Geophysics program, Prof. Norm Murray (CITA (Canadian Institute of Theoretical Astrophysics)) and I have been conducting investigations of the long-term dynamics of small bodies in the outer solar system. This grant, and its successor NAG5-10365, supports travel for collaboration by the Investigators and also supports Murray during an annual one month visit to the CfA (Harvard-Smithsonian Center for Astrophysics) for further collaboration. In the course of this grant we made a number of advances in solar system dynamics. For example, we developed an analytic model for the origin and consequence of chaos associated with three-body resonances in the asteroid belt. This has been shown to be important for the delivery of near Earth objects (NEO). We later extended this model to three-body resonances among planets. We were able to show that the numerically identified chaos among the outer planets results from a three-body resonance involving Jupiter, Saturn, and Uranus. The resulting paper was awarded the 1999 Newcomb Cleveland award from the AAAS (American Association for the Advancement of Science). This award singles out one paper published in Science each year for distinction. A list of grant-related publications is presented, with abstracts included.

Solar thermoelectricity via advanced latent heat storage: A cost-effective small-scale CSP application

NASA Astrophysics Data System (ADS)

Glatzmaier, G. C.; Rea, J.; Olsen, M. L.; Oshman, C.; Hardin, C.; Alleman, J.; Sharp, J.; Weigand, R.; Campo, D.; Hoeschele, G.; Parilla, P. A.; Siegel, N. P.; Toberer, E. S.; Ginley, D. S.

2017-06-01

We are developing a novel concentrating solar electricity-generating technology that is both modular and dispatchable. Solar ThermoElectricity via Advanced Latent heat Storage (STEALS) uses concentrated solar flux to generate high-temperature thermal energy, which directly converts to electricity via thermoelectric generators (TEGs), stored within a phase-change material (PCM) for electricity generation at a later time, or both allowing for simultaneous charging of the PCM and electricity generation. STEALS has inherent features that drive its cost-competitive scale to be much smaller than current commercial concentrating solar power (CSP) plants. Most obvious is modularity of the solid-state TEG, which favors smaller scales in the kilowatt range as compared to CSP steam turbines, which are minimally 50 MWe for commercial power plants. Here, we present techno-economic and market analyses that show STEALS can be a cost-effective electricity-generating technology with particular appeal to small-scale microgrid applications. We evaluated levelized cost of energy (LCOE) for STEALS and for a comparable photovoltaic (PV) system with battery storage. For STEALS, we estimated capital costs and the LCOE as functions of the type of PCM including the use of recycled aluminum alloys, and evaluated the cost tradeoffs between plasma spray coatings and solution-based boron coatings that are applied to the wetted surfaces of the PCM subsystem. We developed a probabilistic cost model that accounts for uncertainties in the cost and performance inputs to the LCOE estimation. Our probabilistic model estimated LCOE for a 100-kWe STEALS system that had 5 hours of thermal storage and 8-10 hours of total daily power generation. For these cases, the solar multiple for the heliostat field varied between 1.12 and 1.5. We identified microgrids as a likely market for the STEALS system. We characterized microgrid markets in terms of nominal power, dispatchability, geographic location, and customer type, and specified additional features for STEALS that are needed to meet the needs of this growing power market.

The Lord of the Rings - Deep Learning Craters on the Moon and Other Bodies

NASA Astrophysics Data System (ADS)

Silburt, Ari; Ali-Dib, Mohamad; Zhu, Chenchong; Jackson, Alan; Valencia, Diana; Kissin, Yevgeni; Tamayo, Daniel; Menou, Kristen

2018-01-01

Crater detection has traditionally been done via manual inspection of images, leading to statistically significant disagreements between scientists for the Moon's crater distribution. In addition, there are millions of uncategorized craters on the Moon and other Solar System bodies that will never be classified by humans due to the time required to manually detect craters. I will show that a deep learning model trained on the near-side of the Moon can successfully reproduce the crater distribution on the far-side, as well as detect thousands of small, new craters that were previously uncharacterized. In addition, this Moon-trained model can be transferred to accurately classify craters on Mercury. It is therefore likely that this model can be extended to classify craters on all Solar System bodies with Digital Elevation Maps. This will facilitate, for the first time ever, a systematic, accurate, and reproducible study of the crater records throughout the Solar System.

X makes nine: a distant ice giant in the solar system.

PubMed

van den Berg, Hugo A

2016-06-01

Ever since Pluto lost its status as one of the main planets of our solar system and was demoted to just another frozen denizen of the Kuiper belt, we have had to make do with eight, albeit in a pleasing symmetry, with four rocky ones this side of the asteroid belt and four giants on the far side. Now it looks like number nine is back on the slate: the existence of a large planet, about ten times as massive as Earth and hundreds of times more distant from the Sun than Earth itself, has been postulated to explain the curiously bunched-up orbits of several small celestial bodies, far beyond the orbit of Neptune. To date, we have only "proof by simulation" and we are yet to observe this massive planet in the backyard of our solar system by more direct means. However, powerful new telescopes should provide visual evidence within the next few decades.

Heat storage with an incongruently melting salt hydrate as storage medium based on the extra water principle

NASA Astrophysics Data System (ADS)

Furbo, S.

1980-12-01

The extra water principle, a heat of fusion storage method, is described. The extra water principle uses an inorganic, incongruently melting salt hydrate as a reliable and stable storage medium in an inexpensive way. Different heat storages using the extra water principle are described. The advantages of using a heat fusion storage unit based on Na2S2O(3).5H2O and the extra water principle instead of a traditional hot water tank in small solar heating systems for domestic hot water supply are shown. In small solar heating systems the heat fusion storage supplies all the wanted hot water in the summer during longer periods than an ordinary hot water storage. It is concluded that the heat of fusion storage is favourable in domestic hot water supply systems with an auxiliary energy source which during the summer have a large energy consumption compared with the energy demands for the hot water supply.

Asteroids Search Results in Large Photographic Sky Surveys

NASA Astrophysics Data System (ADS)

Shatokhina, S. V.; Kazantseva, L. V.; Yizhakevych, O. M.; Eglitis, I.; Andruk, V. M.

Photographic observations of XX century contained numerous and varied information about all objects and events of the Universe fixed on plates. The original and interesting observations of small bodies of the Solar system in previous years can be selected and used for various scientific tasks. Existing databases and online services can help make such selection easily and quickly. The observations of chronologically earlier ppositions, photometric evaluation of brightness for long periods of time allow refining the orbits of asteroids and identifying various non-stationaries. Photographic observations of Northern Sky Survey project and observations of clusters in UBVR bands were used for global search for small bodies of Solar system. Total we founded 2486 positions of asteroids and 13 positions of comets. All positions were compared with ephemeris. It was found that 80 positions of asteroids have a moment of observation preceding their discovery, and 19 of them are chronologically the earliest observations of these asteroids in the world.

Mass Determination of Small Bodies in the Solar System

NASA Astrophysics Data System (ADS)

Paetzold, M.

2017-12-01

The masses and gravity fields of the planetary bodies were determined by radio tracking of spacecraft flying by or orbiting that body at a suffiently close distance. Small bodies (asteroids, cometary nuclei...) of the solar system pose certain challenges in order to reveal their masses and gravity fields. Those challenges mostly concerns spacecraft safety and/or optimal instrment operations. In order to resolve an acceptable Doppler shift with regard to the frequency noise, a spacecraft shall flyby at close distances, at slow speed and at an optimal flyby geometry for a given body mass. This cannot always be achieved. The flybys of Mars Express at Phobos, the flyby of Rosetta at asteroid Lutetia, its orbiting about the nucleus of 67P/Churyumov-Gerasimenko shall be reviewed. The prospects and challenges of future flybys like New Horizons at 2016MU69 and Lucy at the Trojan asteroids shall be presented.

Distribution and solar wind control of compressional solar wind-magnetic anomaly interactions observed at the Moon by ARTEMIS

NASA Astrophysics Data System (ADS)

Halekas, J. S.; Poppe, A. R.; Lue, C.; Farrell, W. M.; McFadden, J. P.

2017-06-01

A statistical investigation of 5 years of observations from the two-probe Acceleration, Reconnection, Turbulence, and Electrodynamics of Moon's Interaction with the Sun (ARTEMIS) mission reveals that strong compressional interactions occur infrequently at high altitudes near the ecliptic but can form in a wide range of solar wind conditions and can occur up to two lunar radii downstream from the lunar limb. The compressional events, some of which may represent small-scale collisionless shocks ("limb shocks"), occur in both steady and variable interplanetary magnetic field (IMF) conditions, with those forming in steady IMF well organized by the location of lunar remanent crustal magnetization. The events observed by ARTEMIS have similarities to ion foreshock phenomena, and those observed in variable IMF conditions may result from either local lunar interactions or distant terrestrial foreshock interactions. Observed velocity deflections associated with compressional events are always outward from the lunar wake, regardless of location and solar wind conditions. However, events for which the observed velocity deflection is parallel to the upstream motional electric field form in distinctly different solar wind conditions and locations than events with antiparallel deflections. Consideration of the momentum transfer between incoming and reflected solar wind populations helps explain the observed characteristics of the different groups of events.