Development of a high-energy distributed energy source electromagnetic railgun with improved energy conversion efficiency

NASA Astrophysics Data System (ADS)

Tower, M. M.; Haight, C. H.

1984-03-01

The development status of a single-pulse distributed-energy-source electromagnetic railgun (ER) based on the design of Tower (1982) is reviewed. The five-stage ER is 3.65 m long, with energy inputs every 30 cm starting at the breech and a 12.7-mm-square bore cross section, and is powered by a 660-kJ 6-kV modular capacitor bank. Lexan cubes weighing 2.5 grams have been accelerated to velocities up to 8.5 km/sec at 500 kA and conversion efficiency up to 20 percent. Design goal for a 20-mm-sq-cross-section ER is acceleration of a 60-g projectile to 3-4 km/sec at 35-percent efficiency. Drawings, photographs, and graphs of performance are provided.

Electromagnetic launchers

NASA Astrophysics Data System (ADS)

Kolm, H.; Mongeau, P.; Williams, F.

1980-09-01

Recent advances in energy storage, switching and magnet technology make electromagnetic acceleration a viable alternative to chemical propulsion for certain tasks, and a means to perform other tasks not previously feasible. Applications include the acceleration of gram-size particles for hypervelocity research and the initiation of fusion by impact, a replacement for chemically propelled artillery, the transportation of cargo and personnel over inaccessible terrain, and the launching of space vehicles to supply massive space operations, and for the disposal of nuclear waste. The simplest launcher of interest is the railgun, in which a short-circuit slide or an arc is driven along two rails by direct current. The most sophisticated studied thus far is the mass driver, in which a superconducting shuttle bucket is accelerated by a line of pulse coils energized by capacitors at energy conversion efficiencies better than 90%. Other accelerators of interest include helical, brush-commutated motors, discrete coil arc commutated drivers, flux compression momentum transformers, and various hybrid electrochemical devices.

Electro-Thermal-Mechanical Simulation Capability Final Report

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

White, D

This is the Final Report for LDRD 04-ERD-086, 'Electro-Thermal-Mechanical Simulation Capability'. The accomplishments are well documented in five peer-reviewed publications and six conference presentations and hence will not be detailed here. The purpose of this LDRD was to research and develop numerical algorithms for three-dimensional (3D) Electro-Thermal-Mechanical simulations. LLNL has long been a world leader in the area of computational mechanics, and recently several mechanics codes have become 'multiphysics' codes with the addition of fluid dynamics, heat transfer, and chemistry. However, these multiphysics codes do not incorporate the electromagnetics that is required for a coupled Electro-Thermal-Mechanical (ETM) simulation. There aremore » numerous applications for an ETM simulation capability, such as explosively-driven magnetic flux compressors, electromagnetic launchers, inductive heating and mixing of metals, and MEMS. A robust ETM simulation capability will enable LLNL physicists and engineers to better support current DOE programs, and will prepare LLNL for some very exciting long-term DoD opportunities. We define a coupled Electro-Thermal-Mechanical (ETM) simulation as a simulation that solves, in a self-consistent manner, the equations of electromagnetics (primarily statics and diffusion), heat transfer (primarily conduction), and non-linear mechanics (elastic-plastic deformation, and contact with friction). There is no existing parallel 3D code for simulating ETM systems at LLNL or elsewhere. While there are numerous magnetohydrodynamic codes, these codes are designed for astrophysics, magnetic fusion energy, laser-plasma interaction, etc. and do not attempt to accurately model electromagnetically driven solid mechanics. This project responds to the Engineering R&D Focus Areas of Simulation and Energy Manipulation, and addresses the specific problem of Electro-Thermal-Mechanical simulation for design and analysis of energy manipulation systems such as magnetic flux compression generators and railguns. This project compliments ongoing DNT projects that have an experimental emphasis. Our research efforts have been encapsulated in the Diablo and ALE3D simulation codes. This new ETM capability already has both internal and external users, and has spawned additional research in plasma railgun technology. By developing this capability Engineering has become a world-leader in ETM design, analysis, and simulation. This research has positioned LLNL to be able to compete for new business opportunities with the DoD in the area of railgun design. We currently have a three-year $1.5M project with the Office of Naval Research to apply our ETM simulation capability to railgun bore life issues and we expect to be a key player in the railgun community.« less

Efficiency equations of the railgun

NASA Astrophysics Data System (ADS)

Sadedin, D. R.

1984-03-01

The feasibility of an employment of railguns for large scale applications, such as space launching, will ultimately be determined by efficiency considerations. The present investigation is concerned with the calculation of the efficiencies for constant current railguns. Elementary considerations are discussed, taking into account a simple condition for high efficiency, the magnetic field of the rails, and the acceleration force on the projectile. The loss in a portion of the rails is considered along with rail loss comparisons, applications to the segmented gun, rail losses related to the constant resistance per unit length, efficiency expressions, and arc, or muzzle voltage energy.

The use of nested chevron rails in a distributed energy store railgun

NASA Astrophysics Data System (ADS)

Marshall, R. A.

1984-03-01

It is pointed out that the large amounts of energy required by electromagnetic launchers will necessitate that energy stores be distributed along their length. The nested chevron rail construction will make it possible for a railgun launcher to be produced in which most of the switching requirements for the launcher/energy store system will be met automatically. Each nested chevron-shaped conductor will be electrically insulated from its neighbors, and each opposing chevron pair (one on each rail) will be connected to the terminals of one energy store (Marshall, 1982). It is explained that as the projectile moves down the railgun the chevrons and associated energy stores at first are unaffected by the approach. At this time the inductors can be charged, and any other preliminary operation can be performed. When the armature comes into contact with the Nth chevron, charge begins to flow from the Nth energy storage system; it flows through one chevron, into the armature, out of the armature into the other chevron, and from that chevron back to the energy storage system.

Distributed-current-feed and distributed-energy-store railguns

NASA Astrophysics Data System (ADS)

Holland, L. D.

1984-03-01

In connection with advances in railgun technology evolution toward the development of systems for specific applications, investigations are being conducted regarding a wide variety of power supply and railgun systems. The present study is concerned with the development of the distributed railguns and the introduction of a new type of railgun system specifically designed for applications requiring long accelerators. It is found that the distributed railguns offer a solution to the limits on performance of the breech-fed railguns as the length of the rails becomes large. Attention is given to the pulse-forming network and breech-fed railgun, the breech-fed railgun with parallel pulse-forming network, a distributed-energy-store railgun, a distributed-current-feed (DCF) railgun, and a DCF railgun launcher.

Distributed energy store railgun - The limiting case

NASA Astrophysics Data System (ADS)

Marshall, Richard A.

1991-01-01

When the limiting case of a distributed energy store railgun is analyzed, (i.e., the case where the space between adjacent energy stores become indefinitely small) three important results are obtained. First, the shape of the current pulse delivered by each store is sinusoidal with an exponential tail. Second, the rail-to-rail voltage behind the rearmost active store approaches zero. Third, it is not possible to choose parameters in such a way that capacitor crowbars can be eliminated.

Investigation of Elliptical Cooling Channels for a Naval Electromagnetic Railgun

DTIC Science & Technology

2005-05-09

Numerical Recipes in C : The Art of Scientific Computing, Second Edition. Cambridge: Cambridge University Press, 1992. Ramanujan , S. Ramanujan’s...by Midshipman 1/ c Elizabeth R. Kealey, Class of 2005 United States Naval Academy Annapolis, MD ___________________________________ (signature...system 55 10 Equation 46: Fourier number 55 Equation 47: General heat equation with coefficients a, b, c , and d 55 Equation 48: Tridiagonal matrix

Railguns

NASA Astrophysics Data System (ADS)

Marshall, R. A.

Descriptions are given of the following railgun systems: the fast-capacitor/inductor system, the slow-capacitor/inductance system, the homopolar generator/inductor system, the distributed energy store system, and the flux compressor powered railgun. Attention is also given to the inverse railgun flux compressor, where the piston is driven between the rails along which the inverted chevron armature slides. The development of the railgun since World War II is surveyed. It is noted that the most pressing need at present is for cheaper, simpler energy stores to couple to the railguns.

The ringer - An efficient, high repetition rate circuit for electromagnetic launchers

NASA Astrophysics Data System (ADS)

Giorgi, D.; Helava, H.; Lindner, K.; Long, J.; Zucker, O.

1989-01-01

The Meatgrinder is an efficient, current-multiplying circuit which can be used to optimize the energy transfer to various electromagnetic gun configurations. The authors present a simple variant of the Meatgrinder circuit which permits a first-order current profiling into the gun and recovery of the inductive energy in the barrel at a high repetition rate. The circuit is basically a one-stage Meatgrinder which utilizes the ringing of the energy storage capacitor (less than 40 percent reversal) to perform the opening switch function and a solid-state diode as the crowbar switch between the two mutually coupled inductors. With resonant charging, this results in a completely passive, high-repetiton-rate electromagnetic-gun power supply. Since most of the barrel energy is recovered, a railgun with negligible muzzle flash can be realized.

Electromagnetic Launchers and Guns. Phase 1

DTIC Science & Technology

1980-06-01

a high-speed maglev transportation system based on a linear synchronous motor (1,2,3). In 1975 Gerard K. O’Neill of Princeton University...fact that the very important railgun- homopolar launcher technology is already being pursued at Westinghouse and university of Texas, Austin. The...shown in Fig. 14 on the following page. There are three comparable options for energy storage: an engine-driven homopolar generator followed by an

Navy Perspective on Joint Force Interdependence

DTIC Science & Technology

2015-01-01

commanders, or produce unaffordable options for the Nation. Rather than expending our finite energy on rehashing roles and missions, or com- mitting...unclassified c. THIS PAGE unclassified Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 JFQ 76, 1st Quarter 2015 Greenert 11 preserve our...avoiding unaf- fordable duplicative efforts by teaming on the promising capabilities of the electromagnetic railgun, a game-changer in defeating cruise

Preliminary analysis of space mission applications for electromagnetic launchers

NASA Technical Reports Server (NTRS)

Miller, L. A.; Rice, E. E.; Earhart, R. W.; Conlon, R. J.

1984-01-01

The technical and economic feasibility of using electromagnetically launched EML payloads propelled from the Earth's surface to LEO, GEO, lunar orbit, or to interplanetary space was assessed. Analyses of the designs of rail accelerators and coaxial magnetic accelerators show that each is capable of launching to space payloads of 800 KG or more. A hybrid launcher in which EML is used for the first 2 KM/sec followed by chemical rocket stages was also tested. A cost estimates study shows that one to two EML launches per day are needed to break even, compared to a four-stage rocket. Development models are discussed for: (1) Earth orbital missions; (2) lunar base supply mission; (3) solar system escape mission; (4) Earth escape missions; (5) suborbital missions; (6) electromagnetic boost missions; and (7) space-based missions. Safety factors, environmental impacts, and EML systems analysis are discussed. Alternate systems examined include electrothermal thrustors, an EML rocket gun; an EML theta gun, and Soviet electromagnetic accelerators.

International Space Station-Based Electromagnetic Launcher for Space Science Payloads

NASA Technical Reports Server (NTRS)

Jones, Ross M.

2013-01-01

A method was developed of lowering the cost of planetary exploration missions by using an electromagnetic propulsion/launcher, rather than a chemical-fueled rocket for propulsion. An electromagnetic launcher (EML) based at the International Space Station (ISS) would be used to launch small science payloads to the Moon and near Earth asteroids (NEAs) for the science and exploration missions. An ISS-based electromagnetic launcher could also inject science payloads into orbits around the Earth and perhaps to Mars. The EML would replace rocket technology for certain missions. The EML is a high-energy system that uses electricity rather than propellant to accelerate payloads to high velocities. The most common type of EML is the rail gun. Other types are possible, e.g., a coil gun, also known as a Gauss gun or mass driver. The EML could also "drop" science payloads into the Earth's upper

Project RAMA: Reconstructing Asteroids Into Mechanical Automata

NASA Technical Reports Server (NTRS)

Dunn, Jason; Fagin, Max; Snyder, Michael; Joyce, Eric

2017-01-01

Many interesting ideas have been conceived for building space-based infrastructure in cislunar space. From O'Neill's space colonies, to solar power satellite farms, and even prospecting retrieved near earth asteroids. In all the scenarios, one thing remained fixed - the need for space resources at the outpost. To satisfy this need, O'Neill suggested an electromagnetic railgun to deliver resources from the lunar surface, while NASA's Asteroid Redirect Mission called for a solar electric tug to deliver asteroid materials from interplanetary space. At Made In Space, we propose an entirely new concept. One which is scalable, cost effective, and ensures that the abundant material wealth of the inner solar system becomes readily available to humankind in a nearly automated fashion. We propose the RAMA architecture, which turns asteroids into self-contained spacecraft capable of moving themselves back to cislunar space. The RAMA architecture is just as capable of transporting conventional-sized asteroids on the 10-meter length scale as transporting asteroids 100 meters or larger, making it the most versatile asteroid retrieval architecture in terms of retrieved-mass capability. This report describes the results of the Phase I study funded by the NASA NIAC program for Made In Space to establish the concept feasibility of using space manufacturing to convert asteroids into autonomous, mechanical spacecraft. Project RAMA, Reconstituting Asteroids into Mechanical Automata, is designed to leverage the future advances of additive manufacturing (AM), in-situ resource utilization (ISRU) and in-situ manufacturing (ISM) to realize enormous efficiencies in repeated asteroid redirect missions. A team of engineers at Made In Space performed the study work with consultation from the asteroid mining industry, academia, and NASA. Previous studies for asteroid retrieval have been constrained to studying only asteroids that are both large enough to be discovered, and small enough to be captured and transported using Earth-launched propulsion technology. Project RAMA is not forced into this constraint. The mission concept studied involved transporting a much larger approximately 50-meter asteroid to cislunar space. Demonstration of transport of a 50-meter-class asteroid has several ground-breaking advantages. First, the returned material is of an industrial, rather than just scientific, quantity (greater than 10,000 tonnes versus approximately10s of tonnes). Second, the "useless" material in the asteroid is gathered and expended as part of the asteroid's propulsion system, allowing the returned asteroid to be considerably "purer" than a conventional asteroid retrieval mission. Third, the infrastructure used to convert and return the asteroid is reusable, and capable of continually returning asteroids to cislunar space.

Solid-to-hybrid transitioning armature railgun with non-conforming-to-prejudice bore profile

DOEpatents

Solberg, Jerome Michael

2012-12-04

An improved railgun, railgun barrel, railgun projectile, and railgun system for accelerating a solid-to-hybrid transitioning armature projectile using a barrel having a bore that does not conform to a cross-sectional profile of the projectile, to contact and guide the projectile only by the rails in a low pressure bore volume so as to minimize damage, failure, and/or underperformance caused by plasma armatures, insulator ablation, and/or restrikes.

Dead Zone Oscillator Control for Communication-Free Synchronization of Paralleled, Three-Phase, Current-Controlled Inverters

DTIC Science & Technology

2016-05-11

the phases of the system load and ground, so to size the voltage divider appropriately Vsys is set equal to the maximum phase-to-ground voltage. The...civilian and military systems is increasing due to technological improvements in power conversion and changing requirements in system loads. The development...of high-power pulsed loads on naval platforms, such as the Laser Weapon System (LaWS) and the electromagnetic railgun, calls for the ability to

Omni-directional railguns

DOEpatents

Shahinpoor, Mohsen

1995-01-01

A device for electromagnetically accelerating projectiles. The invention features two parallel conducting circular plates, a plurality of electrode connections to both upper and lower plates, a support base, and a projectile magazine. A projectile is spring-loaded into a firing position concentrically located between the parallel plates. A voltage source is applied to the plates to cause current to flow in directions defined by selectable, discrete electrode connections on both upper and lower plates. Repulsive Lorentz forces are generated to eject the projectile in a 360 degree range of fire.

Electromagnetic Launch Technology Assessment. Scientific Basis and Unified Treatment: Forces and Electromechanical Power Conversion (Analytical and Numerical Methods),

DTIC Science & Technology

1990-06-01

on simple railgun accelerators andI homopolar generators. Complex rotating flux compressors would drastically improve the performance of EM launchers...velocities. If this is the direction of improvement, then energies stored in the electric trains built with linear electric motors in Japan and Western I...laboratories which had power supplies 3 already built for other programs ( homopolar generators in conjunction with an inductor and an opening switch

Magnetoplasma sheath waves on a conducting tether in the ionosphere with applications to EMI propagation on large space structures

NASA Technical Reports Server (NTRS)

Balmain, K. G.; James, H. G.; Bantin, C. C.

1991-01-01

A recent space experiment confirmed sheath-wave propagation of a kilometer-long insulated wire in the ionosphere, oriented parallel to the Earth's magnetic field. This space tether experiment, Oedipus-A, showed a sheath-wave passband up to about 2 MHz and a phase velocity somewhat slower than the velocity of light in a vacuum, and also demonstrated both ease of wave excitation and low attenuation. The evidence suggests that, on any large structure in low Earth orbit, transient or continuous wave electromagnetic interference, once generated, could propagate over the structure via sheath waves, producing unwanted signal levels much higher than in the absence of the ambient plasma medium. Consequently, there is a need for a review of both electromagnetic interference/electromagnetic compatibility standards and ground test procedures as they apply to large structures in low Earth orbit.

Ecology of Near-Earth Space

NASA Astrophysics Data System (ADS)

Nikoghosyan, E. H.

2017-12-01

The technical achievements of our civilization are accompanied by certain negative consequences affect the near-Earth space. The problem of clogging of near-Earth space by "space debris" as purely theoretical arose essentially as soon as the first artificial satellite in 1957 was launched. Since then, the rate of exploitation of outer space has increased very rapidly. As a result, the problem of clogging of near-Earth space ceased to be only theoretical and transformed into practical. Presently, anthropogenic factors of the development of near-Earth space are divided into several categories: mechanical, chemical, radioactive and electromagnetic pollution.

Omni-directional railguns

DOEpatents

Shahinpoor, M.

1995-07-25

A device is disclosed for electromagnetically accelerating projectiles. The invention features two parallel conducting circular plates, a plurality of electrode connections to both upper and lower plates, a support base, and a projectile magazine. A projectile is spring-loaded into a firing position concentrically located between the parallel plates. A voltage source is applied to the plates to cause current to flow in directions defined by selectable, discrete electrode connections on both upper and lower plates. Repulsive Lorentz forces are generated to eject the projectile in a 360 degree range of fire. 4 figs.

Review of Railgun Modeling Techniques: The Computation of Railgun Force and Other Key Factors

NASA Astrophysics Data System (ADS)

Eckert, Nathan James

Currently, railgun force modeling either uses the simple "railgun force equation" or finite element methods. It is proposed here that a middle ground exists that does not require the solution of partial differential equations, is more readily implemented than finite element methods, and is more accurate than the traditional force equation. To develop this method, it is necessary to examine the core railgun factors: power supply mechanisms, the distribution of current in the rails and in the projectile which slides between them (called the armature), the magnetic field created by the current flowing through these rails, the inductance gradient (a key factor in simplifying railgun analysis, referred to as L'), the resultant Lorentz force, and the heating which accompanies this action. Common power supply technologies are investigated, and the shape of their current pulses are modeled. The main causes of current concentration are described, and a rudimentary method for computing current distribution in solid rails and a rectangular armature is shown to have promising accuracy with respect to outside finite element results. The magnetic field is modeled with two methods using the Biot-Savart law, and generally good agreement is obtained with respect to finite element methods (5.8% error on average). To get this agreement, a factor of 2 is added to the original formulation after seeing a reliable offset with FEM results. Three inductance gradient calculations are assessed, and though all agree with FEM results, the Kerrisk method and a regression analysis method developed by Murugan et al. (referred to as the LRM here) perform the best. Six railgun force computation methods are investigated, including the traditional railgun force equation, an equation produced by Waindok and Piekielny, and four methods inspired by the work of Xu et al. Overall, good agreement between the models and outside data is found, but each model's accuracy varies significantly between comparisons. Lastly, an approximation of the temperature profile in railgun rails originally presented by McCorkle and Bahder is replicated. In total, this work describes railgun technology and moderately complex railgun modeling methods, but is inconclusive about the presence of a middle-ground modeling method.

The Electromagnetic Spectrum: Using Light and Color To Search for Astronomical Origins.

ERIC Educational Resources Information Center

Smith, Denise; Eisenhamer, Bonnie; DeVore, Edna

2003-01-01

Discusses various ways to use the National Aeronautics and Space Administration's (NASA) Origin's Education Forum's Electromagnetic Spectrum poster to teach earth science concepts. Includes the poster. (SOE)

A Battery Powered, 200-KW Rapid Capacitor Charger for a Portable Railgun in Burst Mode Operation At 3 RPS

DTIC Science & Technology

2007-06-01

A BATTERY POWERED, 200-KW RAPID CAPACITOR CHARGER FOR A PORTABLE RAILGUN IN BURST MODE OPERATION AT 3 RPS ∗ Raymond Allen and Jesse Neri Plasma... capacitor bank of a low velocity railgun system for countermeasure deployment from aircraft and watercraft. The goal is charge a 15-mF capacitor bank to...In order for this railgun to fire in a burst mode at 3 RPS, a rapid capacitor charger is required. The initial specifications required the rapid

Switching for electric rail guns

NASA Astrophysics Data System (ADS)

Barber, J. P.; Bauer, D. P.

1984-03-01

The switching requirements of single-stage electric railguns powered by inductive energy stores are analyzed, and the design of a 500-kA commutation switch is shown. The closed, commutation, and off states of the switch and the reclosure function at the end of the projectile acceleration are discussed in general terms, and the specific requirements of the railgun facility at Australian National University are listed. The switch designed is essentially a railgun mounted perpendicular to the breech of the electric railgun, with the armature accelerating down copper rails at closing speeds from 50 m/sec at 100 kA to 300 m/sec at 500 kA to commutate current to the railgun. Commutation time and maximum voltage during 200 shots at 400 kA were found to be 50 microsec and 100 V; commutation inductance was 18-20 nH.

Multiple stage railgun

DOEpatents

Hawke, Ronald S.; Scudder, Jonathan K.; Aaland, Kristian

1982-01-01

A multiple stage magnetic railgun accelerator (10) for accelerating a projectile (15) by movement of a plasma arc (13) along the rails (11,12). The railgun (10) is divided into a plurality of successive rail stages (10a-n) which are sequentially energized by separate energy sources (14a-n) as the projectile (15) moves through the bore (17) of the railgun (10). Propagation of energy from an energized rail stage back towards the breech end (29) of the railgun (10) can be prevented by connection of the energy sources (14a-n) to the rails (11,12) through isolation diodes (34a-n). Propagation of energy from an energized rail stage back towards the breech end of the railgun can also be prevented by dividing the rails (11,12) into electrically isolated rail sections (11a-n, 12a-n). In such case means (55a-n) are used to extinguish the arc at the end of each energized stage and a fuse (31) or laser device (61) is used to initiate a new plasma arc in the next energized rail stage.

Effects of Current Guides Destruction at Ultra-fast Acceleration of Macrobodies

NASA Astrophysics Data System (ADS)

Kataev, V. N.; Boriskin, A. S.; Golosov, S. N.; Demidov, V. A.; Klimashov, M. V.; Korolev, P. V.; Makartsev, G. F.; Pikar, A. S.; Russkov, A. S.; Shapovalov, E. V.; Shibitov, Yu. M.

2006-08-01

The paper is devoted to discussion of current guides destruction effects in different accelerators: thermal-electric and electro-magnetic rail accelerator at macrobodies acceleration value of 108-109 m/s2. Experimental results with thermal-electric accelerators powering from megajoule capacitor battery and helical magneto-cumulative generator MCG-100 at currents up to 3.5 MA are analyzed. The process of rails destruction at railgun at pressure magnetic field excess over the limit of metal fluidity is presented. Methods of efficiency coefficient increase of capacitive storage energy transmission to kinetic energy of accelerating body are discussed.

Experimental measurement of ablation effects in plasma armature railguns

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

Parker, J.V.; Parsons, W.M.

1986-01-01

Experimental evidence supporting the importance of ablation in plasma armature railguns is presented. Experiments conducted using the HYVAX and MIDI-2 railguns are described. Several indirect effects of ablation are identified from the experimental results. An improved ablation model of plasma armature dynamics is proposed which incorporates the restrike process.

Experimental measurement of ablation effects in plasma armature railguns

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

Parker, J.V.; Parsons, W.M.

1986-11-01

Experimental evidence supporting the importance of ablation in plasma armature railguns is presented. Experiments conducted using the HYVAX and MIDI-2 railguns are described. Several indirect effects of ablation are identified from the experimental results. An improved ablation model of plasma armature dynamics is proposed which incorporates the restrike process.

NASA's Future Active Remote Sensing Missing for Earth Science

NASA Technical Reports Server (NTRS)

Hartley, Jonathan B.

2000-01-01

Since the beginning of space remote sensing of the earth, there has been a natural progression widening the range of electromagnetic radiation used to sense the earth, and slowly, steadily increasing the spatial, spectral, and radiometric resolution of the measurements. There has also been a somewhat slower trend toward active measurements across the electromagnetic spectrum, motivated in part by increased resolution, but also by the ability to make new measurements. Active microwave instruments have been used to measure ocean topography, to study the land surface. and to study rainfall from space. Future NASA active microwave missions may add detail to the topographical studies, sense soil moisture, and better characterize the cryosphere. Only recently have active optical instruments been flown in space by NASA; however, there are currently several missions in development which will sense the earth with lasers and many more conceptual active optical missions which address the priorities of NASA's earth science program. Missions are under development to investigate the structure of the terrestrial vegetation canopy, to characterize the earth's ice caps, and to study clouds and aerosols. Future NASA missions may measure tropospheric vector winds and make vastly improved measurements of the chemical components of the earth's atmosphere.

Consideration of some fundamental erosion processes encountered in hypervelocity electromagnetic propulsion

NASA Astrophysics Data System (ADS)

Buckingham, A. C.; Hawke, R. S.

1982-09-01

Experimental and theoretical research was conducted jointly at the Livermore and Los Alamos National laboratories on dc electromagnetic railgun Lorentz accelerators. Pellets weighing a few grams to tens of grams were launched at velocities up to better than 11 km/s. The research is addressed to attaining repeated launches of samples at hypervelocity in target impact experiments. In these experiments, shock-induced pressure in the tens of megabars range are obtained for high pressure equations of state research. Primary energy sources of the order of several hundred kJ to a MJ and induction currents of the order of 1 or more MA are necessary for these launches. Erosion and deformation of the conductor rails and the accelerated sample material are continuing problems. The beating, stress, and erosion resulting from simultaneous imposition of rail induction current, dense plasma (armature) interaction, current distribution, magnetic field stresses and projectile/rail contact friction are examined.

Non-US electrodynamic launchers research and development

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

Parker, J.V.; Batteh, J.H.; Greig, J.R.

Electrodynamic launcher research and development work of scientists outside the United States is analyzed and assessed by six internationally recognized US experts in the field of electromagnetic and electrothermal launchers. The assessment covers five broad technology areas: (1) Experimental railguns; (2) Railgun theory and design; (3) Induction launchers; (4) Electrothermal guns; (5) Energy storage and power supplies. The overall conclusion is that non-US work on electrodynamic launchers is maturing rapidly after a relatively late start in many countries. No foreign program challenges the US efforts in scope, but it is evident that the United States may be surpassed in somemore » technologies within the next few years. Until recently, published Russian work focused on hypervelocity for research purposes. Within the last two years, large facilities have been described where military-oriented development has been underway since the mid-1980s. Financial support for these large facilities appears to have collapsed, leaving no effective effort to develop practical launchers for military or civilian applications. Electrodynamic launcher research in Europe is making rapid progress by focusing on a single application, tactical launchers for the military. Four major laboratories, in Britain, France, Germany, and the Netherlands, are working on this problem. Though narrower in scope than the US effort, the European work enjoys a continuity of support that has accelerated its progress. The next decade will see the deployment of electrodynamic launcher technology, probably in the form of an electrothermal-chemical upgrade for an existing gun system. The time scale for deployment of electromagnetic launchers is entirely dependent on the level of research-and-development effort. If resources remain limited, the advantage will lie with cooperative efforts that have reasonably stable funding such as the present French-German program.« less

High Current Systems for HyperV and PLX Plasma Railguns

NASA Astrophysics Data System (ADS)

Brockington, S.; Case, A.; Messer, S.; Elton, R.; Witherspoon, F. D.

2011-10-01

HyperV is developing gas fed, pulsed, plasma railgun accelerators for PLX and other high momentum plasma applications. The present 2.5 cm square-bore plasma railgun forms plasma armatures from high density neutral gas (argon), preionizes it electrothermally, and accelerates the armature with 30 cm long parallel-plate railgun electrodes driven by a pulse forming network (PFN). Recent experiments have successfully formed and accelerated plasma armatures of ~4 mg at 40 km/s, with PFN currents of ~400 kA. In order to further increase railgun performance to the PLX design goal of 8 mg at 50 km/s, the PFN was upgraded to support currents of up to ~750 kA. A high voltage, high current linear array spark-gap switch and flexible, low-inductance transmission line were designed and constructed to handle the increased current load. We will describe these systems and present initial performance data from high current operation of the plasma rail gun from spectroscopy, interferometry, and imaging systems as well as pressure, magnetic field, and optical diagnostics. High current performance of railgun bore materials for electrodes and insulators will also be discussed as well as plans for upcoming experimentation with advanced materials. Supported by the U.S. DOE Joint Program in HEDLP.

Navy Lasers, Railgun, and Hypervelocity Projectile: Background and Issues for Congress

DTIC Science & Technology

2016-03-18

1 Railgun is also spelled as rail gun ; EMRG is also abbreviated as EM railgun; hypervelocity is also...controlled Gatling gun . Employing all these measures reflects a long-standing Navy approach of creating a multi-layered defense against enemy...fact that Navy surface ships can use surface-to-air missiles (SAMs) and their Close-in Weapon System (CIWS) Gatling guns to shoot down only a certain

Prospects and limitations for use of frequency spectrum from 40 to 300 GHz

NASA Technical Reports Server (NTRS)

Catoe, C. E.

1979-01-01

The existing and future use of the electromagnetic spectrum from 40 to 300 gigahertz is discussed. The activities envisioned for this segment of the electromagnetic spectrum fall generically into two basic categories: communications and remote sensing. The communications services considered for this region are focused on the existing and future frequency allocations that are required for terrestrial radio services, space to ground radio services, space to space radio services, and space to deep space radio services. The remote sensing services considered for this region are divided into two groups of activities: earth viewing and space viewing.

Earth Science Geostationary Platform Technology

NASA Technical Reports Server (NTRS)

Wright, Robert L. (Editor); Campbell, Thomas G. (Editor)

1989-01-01

The objective of the workshop was to address problems in science and in four technology areas (large space antenna technology, microwave sensor technology, electromagnetics-phased array adaptive systems technology, and optical metrology technology) related to Earth Science Geostationary Platform missions.

Mass sensitivity studies for an inductively driven railgun

NASA Astrophysics Data System (ADS)

Scanlon, J. J., III; Young, A. F.

1991-01-01

Those areas which result in substantial system mass reductions for an HPG (homopolar generator) driven EML (electromagnetic launcher) are identified. Sensitivity studies are performed by varying launch mass, peak acceleration, launcher efficiency, inductance gradient, injection velocity, barrel mass per unit length, fuel tankage and pump estimates, and component energy and power densities. Two major contributors to the system mass are the allowed number of shots per barrel versus the number required for the mission, and the barrel length. The effects of component performance parameters, such as friction coefficient, injection velocity, ablation coefficient, rail resistivity, armature voltage, peak acceleration, and inductance gradient on these two areas, are addressed.

Solar Eruptions: Coronal Mass Ejections and Flares

NASA Technical Reports Server (NTRS)

Gopalswamy, Nat

2012-01-01

This lecture introduces the topic of Coronal mass ejections (CMEs) and solar flares, collectively known as solar eruptions. During solar eruptions, the released energy flows out from the Sun in the form of magnetized plasma and electromagnetic radiation. The electromagnetic radiation suddenly increases the ionization content of the ionosphere, thus impacting communication and navigation systems. Flares can be eruptive or confined. Eruptive flares accompany CMEs, while confined flares hav only electromagnetic signature. CMEs can drive MHD shocks that accelerate charged particles to very high energies in the interplanetary space, which pose radiation hazard to astronauts and space systems. CMEs heading in the direction of Earth arrive in about two days and impact Earth's magnetosphere, producing geomagnetic storms. The magnetic storms result in a number of effects including induced currnts that can disrupt power grids, railroads, and underground pipelines

Space station user's handbook (Revised)

NASA Technical Reports Server (NTRS)

1972-01-01

A modular space station concept that furnishes facilities which may be used for experimentation and application during earth orbit missions is described in a user's handbook. The subjects discussed are: (1) overall profile and mission activities for five year on-orbit program, (2) electromagnetic energy transmission through earth atmosphere, (3) effects of atmosphere in limiting resolution, and (4) the hydrological cycle as these subjects apply to the space station data acquisition function.

The Feasibility of Railgun Horizontal-Launch Assist

NASA Technical Reports Server (NTRS)

Youngquist, Robert C.; Cox, Robert B.

2011-01-01

Railguns typically operate for a few milliseconds, supplying thousands of G's of acceleration to a small projectile, resulting in exceptional speeds. This paper argues through analysis and experiment, that this "standard" technology can be modified to provide 2-3 G's acceleration to a relatively heavy launch vehicle for a time period exceeding several seconds, yielding a launch assist velocity in excess of Mach 1. The key insight here is that an efficient rail gun operates at a speed approximately given by the system resistance divided by the inductance gradient, which can be tailored because recent MOSFET and ultra-capacitor advances allow very low total power supply resistances with high capacitance and augmented railgun architectures provide a scalable inductance gradient. Consequently, it should now be possible to construct a horizontal launch assist system utilizing railgun based architecture.

Relation between the Electromagnetic Processes in the Near-Earth Space and Dynamics of the Biological Resources in Russian Arctic

NASA Astrophysics Data System (ADS)

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

It is a well-established fact that the electromagnetic processes of different kind occurring in the near- Earth space produce significant effects in the Earth's atmosphere at all altitudes including the ground surface. There are some indications that these processes could influence at least indirectly the human health conditions. In this study we explore relation between perturbations in the solar wind (dynamics of its density, velocity, intensity of the interplanetary magnetic field) and long- term changes in population of some species of Arctic fauna (lemmings, polar foxes, deers, wolves, elks etc.) It was found out that the best statistical coupling between various Space Weather parameters and the changes in populations of the Arctic fauna species appears when the solar wind dynamic pressure magnitude is taken as one of these parameters. It was shown that the secular variations of the solar UV radiation expressed as the Total Solar Irradiance appears to be a space parameter, showing the best correlation with the changes in population of the Arctic fauna species. Such high correlation coefficients as 0.8 are obtained. It is premature now to discuss exact physical mechanisms, which could explain the obtained relations. A possible mutual dependence of some climatic factors and fauna population in Arctic on the Space Weather parameters is discussed in this connection. Conclusion is made that the electromagnetic fields of space origin is an important factor determining dynamics of population of the Arctic fauna species.

Comparison of Two Railgun Power Supply Architectures to Quantify the Energy Dissipated After the Projectile Leaves the Railgun

DTIC Science & Technology

2016-06-01

inch gun on impact [1]. The potential of the EM railgun renders the need to store dangerous explosives associated with the conventional warheads...leaves the gun . The simulation will outline some critical performance characteristics of a buck-boost power supply as compared to a thyristor-based...between the rails and from the projectile position along the length of the gun x [5]: 3 1 2 𔃻 2 2 w o

Solar Eruptions, CMEs and Space Weather

NASA Technical Reports Server (NTRS)

Gopalswamy, Nat

2011-01-01

Coronal mass ejections (CMEs) are large-scale magnetized plasma structures ejected from the Sun and propagate far into the interplanetary medium. CMEs represent energy output from the Sun in the form of magnetized plasma and electromagnetic radiation. The electromagnetic radiation suddenly increases the ionization content of the ionosphere, thus impacting communication and navigation systems. The plasma clouds can drive shocks that accelerate charged particles to very high energies in the interplanetary space, which pose radiation hazard to astronauts and space systems. The plasma clouds also arrive at Earth in about two days and impact Earth's magnetosphere, producing geomagnetic storms. The magnetic storms result in a number of effects including induced currents that can disrupt power grids, railroads, and underground pipelines. This lecture presents an overview of the origin, propagation, and geospace consequences of solar storms.

The motionally induced back-emf in railguns

NASA Astrophysics Data System (ADS)

Graneau, Peter; Thompson, Donald S.; Morrill, Susan L.

1990-04-01

Relative motion between armature and rails in the railgun produces induced emf's. The Lorentz force formula correctly predicts the emf present in the armature but it fails to acknowledge the induction of further emf's in the rails which are proportional to the relative velocity. It is easy to confirm the existence of the additional rail emf's behind and ahead of the armature, by voltage measurements across the muzzle and the breech of the railgun. Neumann's forgotten law of induction, which was first proposed in 1845, correctly accounts for the magnitude and position of all motionally induced emf components in the railgun circuit. The velocity dependent back-emf's in the rails coincide with the Ampere recoil forces in the railheads just behind the armature. Electric power extended in overcoming these back-emf's, and associated with the recoil forces, seem to store elastic strain energy in the rails.

Space shuttle electromagnetic environment experiment. Phase A: Definition study

NASA Technical Reports Server (NTRS)

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

1976-01-01

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

An experiment to measure the one-way velocity of propagation of electromagnetic radiation

NASA Technical Reports Server (NTRS)

Kolen, P.; Torr, D. G.

1982-01-01

An experiment involving commercially available instrumentation to measure the velocity of the earth with respect to absolute space is described. The experiment involves the measurement of the one-way propagation velocity of electromagnetic radiation down a high-quality coaxial cable. It is demonstrated that the experiment is both physically meaningful and exceedingly simple in concept and in implementation. It is shown that with currently available commercial equipment one might expect to detect a threshold value for the component of velocity of the earth's motion with respect to absolute space in the equatorial plane of approximately 10 km/s, which greatly exceeds the velocity resolution required to detect the motion of the solar system with respect to the center of the galaxy.

Advanced Space Transportation Program (ASTP)

NASA Image and Video Library

2000-09-07

The `once upon a time' science fiction concept of a space elevator has been envisioned and studied as a real mass transportation system in the latter part of the 21st century. David Smitherman of NASA's Marshall Space Flight Center's Advanced Projects Office has compiled plans for such an elevator. The space elevator concept is a structure extending from the surface of the Earth to geostationary Earth orbit (GEO) at 35,786 km in altitude. The tower would be approximately 50 km tall with a cable tethered to the top. Its center mass would be at GEO such that the entire structure orbits the Earth in sync with the Earth's rotation maintaining a stationary position over its base attachment at the equator. Electromagnetic vehicles traveling along the cable could serve as a mass transportation system for transporting people, payloads, and power between space and Earth. This illustration by artist Pat Rawling shows the concept of a space elevator as viewed from the geostationary transfer station looking down the length of the elevator towards the Earth.

Studying the Earth from space

USGS Publications Warehouse

,

1981-01-01

scene, as man sees it, on film sensitive to that part of the electromagnetic spectrum called visible energy. Electromagnetic energy travels in waves of various lengths; most are invisible to the human eye. Wavelengths progressively longer than those that the eye can see are infrared and microwave. Wavelengths progressively shorter than the eye can see are ultraviolet, X-rays, and gamma rays.

An advanced EM railgun design

NASA Astrophysics Data System (ADS)

Hallse, R. L.; Weiman, S. M.

1986-11-01

A progress report is presented from a study of structural design concepts for a large, square-bore, multi-shot railgun. The railgun is to have multi-MA current, a barrel longer than 15 ft, a thermally-managed breech 3 ft long, and pre-stressed internal components. The design, as of early 1986, had a one-piece monolithic circular shell, S-glass/epoxy insulators, and bolt-loaded steel pre-stressed plates. Thermal management is achieved with longitudinal cooling slots with numerous water and air inlets. The device is instrumented for gun current, voltage, bore velocity, magnetic field, rail and armature current, bore dimensions and coolant temperature.

Research in space physics at the University of Iowa

NASA Technical Reports Server (NTRS)

Vanallen, J. A.

1976-01-01

Energetic particles in outer space and their relationship to electric, magnetic, and electromagnetic fields associated with the earth, sun, moon, and planets, and the interplanetary medium are investigated. Special attention was given to observations of earth and moon satellites and interplanetary spacecraft; phenomenological analysis and interpretation were emphasized. Data also cover ground based on radio astronomical and optical techniques and theoretical problems in plasma physics as revelant to solar planetary and interplanetary phenomena.

Project MANTIS: A MANTle Induction Simulator for coupling geodynamic and electromagnetic modeling

NASA Astrophysics Data System (ADS)

Weiss, C. J.

2009-12-01

A key component to testing geodynamic hypotheses resulting from the 3D mantle convection simulations is the ability to easily translate the predicted physiochemical state to the model space relevant for an independent geophysical observation, such as earth's seismic, geodetic or electromagnetic response. In this contribution a new parallel code for simulating low-frequency, global-scale electromagnetic induction phenomena is introduced that has the same Earth discretization as the popular CitcomS mantle convection code. Hence, projection of the CitcomS model into the model space of electrical conductivity is greatly simplified, and focuses solely on the node-to-node, physics-based relationship between these Earth parameters without the need for "upscaling", "downscaling", averaging or harmonizing with some other model basis such as spherical harmonics. Preliminary performance tests of the MANTIS code on shared and distributed memory parallel compute platforms shows favorable scaling (>70% efficiency) for up to 500 processors. As with CitcomS, an OpenDX visualization widget (VISMAN) is also provided for 3D rendering and interactive interrogation of model results. Details of the MANTIS code will be briefly discussed here, focusing on compatibility with CitcomS modeling, as will be preliminary results in which the electromagnetic response of a CitcomS model is evaluated. VISMAN rendering of electrical tomography-derived electrical conductivity model overlain by an a 1x1 deg crustal conductivity map. Grey scale represents the log_10 magnitude of conductivity [S/m]. Arrows are horiztonal components of a hypothetical magnetospheric source field used to electromagnetically excite the conductivity model.

The Planeterrella: an Analog Model for Teaching About the Invisible Electromagnetic Processes Driving Space Weather

NASA Astrophysics Data System (ADS)

Masongsong, E. V.; Glesener, G. B.; Angelopoulos, V.; Lilensten, J.; Bingley, L.

2015-12-01

The Planeterrella can be used as an analog to help students visualize and understand the electromagnetic processes driving space weather that affect our daily lives. Solar storms and solar wind charged particles (plasma) cause "space weather" via their interaction with Earth's protective magnetic shield, the magnetosphere. The Planeterrella uses magnetized spheres in a vacuum chamber to demonstrate solar wind energy transfer to Earth and planets, with polar localization of aurora due to charged particles traveling along geomagnetic field lines. The Planeterrella provides a unique opportunity to experience and manipulate plasma, the dominant form of matter in our universe, yet seldom observable on Earth. Severe space weather events produce spectacular auroral displays as well as devastating consequences: radiation exposure to air and space travelers, prolonged radio blackouts, and damage to critical GPS and communications satellites. We will (1) discuss ways in which the Planeterrella may be most useful in classroom settings, including large lecture halls, laboratories, and small discussion sessions; (2) provide information on how instructors can produce their own Planeterrella for their courses; and (3) invite meeting attendees to engage in a discussion on how we might be able to improve on the current design of the Planeterrella, and how to reach students in more parts of the world.

The HyperV 8000 μg, 50 km/s Plasma Railgun for PLX

NASA Astrophysics Data System (ADS)

Brockington, Samuel; Case, Andrew; Messer, Sarah; Wu, Linchun; Witherspoon, F. Douglas

2012-10-01

HyperV has developed a gas fed, pulsed, plasma railgun which accelerates 8000 μg of argon to 50 km/s meeting the performance requirements originally specified for the Plasma Liner Experiment (PLX). The present 2.5 cm square-bore plasma railgun forms plasma armatures from high density neutral gas, pre-ionizes it electro-thermally, and accelerates the armature with 30 cm long parallel-plate railgun electrodes driven by a pulse forming network (PFN). A high voltage, high current linear array spark-gap switch and flexible, low-inductance transmission line were designed and constructed to handle the increased current load. We will describe these systems and present initial performance data from high current operation of the plasma rail gun from spectroscopy, interferometry, and imaging systems. Measurements of momentum, pressure, magnetic field, and other optical diagnostics will also be discussed as well as plans for upcoming experimentation to increase performance even further. Work supported by USDOE under DE-FG02-05ER54810 and DE-FG02-08ER85114.

Soyuz 22: New contribution to earth study from space

NASA Technical Reports Server (NTRS)

Vedeshin, L. A.; Ivanov, V. V.; Sulidi-Kondratyev, Y. D.

1977-01-01

The mission of space flight Soyuz-22 was to develop new and improved methods and means for finding tthe Earth's natural resources from outer space to aid the economy. With the help of the new multispectral space camera, MKF-6, the cosmonauts were able to photograph selected areas of U.S.S.R. and the German Democratic Republic in 4 visible and 2 infrared regions of the spectrum. The MKF-6 can simultaneously photograph areas in 6 spectral regions and register both the natural electromagnetic radiation of surface objects and the solar radiation reflected by them.

Application of superconducting technology to earth-to-orbit electromagnetic launch systems

NASA Technical Reports Server (NTRS)

Hull, J. R.; Carney, L. M.

1988-01-01

Benefits may occur by incorporating superconductors, both existing and those currently under development, in one or more parts of a large-scale electromagnetic launch (EML) system that is capable of delivering payloads from the surface of the Earth to space. The use of superconductors for many of the EML components results in lower system losses; consequently, reductions in the size and number of energy storage devices are possible. Applied high-temperature superconductivity may eventually enable novel design concepts for energy distribution and switching. All of these technical improvements have the potential to reduce system complexity and lower payload launch costs.

Space based astronomy: Teacher's guide with activities

NASA Technical Reports Server (NTRS)

Rosenberg, Carla B. (Editor); Weiler, Edward; Morrow, Cherilyn; Bacon, Pamela M.; Thorne, Muriel; Blanchard, Paul A.; Howard, Sethane; Pengra, Patricia R.; Brown, Deborah A.; Winrich, Ralph

1994-01-01

This curriculum guide uses hands-on activities to help students and teachers understand the significance of space-based astronomy - astronomical observations made from outer space. The guide contains few of the traditional activities found in many astronomy guides such as constellation studies, lunar phases, and planetary orbits. Instead, it tells the story of why it is important to observe celestial objects from outer space and how to study the entire electromagnetic spectrum. The guide begins with a survey of astronomy related NASA spacecraft. This is followed by a collection of activities in four units: (1) the atmospheric filter; (2) the electromagnetic spectrum; (3) collecting electromagnetic radiation; and (4) down to Earth. A curriculum index identifies the curriculum areas each activity addresses. The guide concludes with a glossary, reference list, a NASA Resources list, and an evaluation card. It is designed for students in grades 5 through 8.

Electromagnetic deep-probing (100-1000 KMS) of the Earth's interior from artificial satellites: Constraints on the regional emplacement of crustal resources

NASA Technical Reports Server (NTRS)

Hermance, J. F. (Principal Investigator)

1981-01-01

Model simulations show that induction in a spherical Earth by distant magnetospheric sources can contribute magnetic field fluctuations at MAGSAT altitudes which are 30 to 40 percent of the external field amplitudes. When the characteristic dimensions (e.g. depth of penetration, etc) of a particular situations are small compared with the Earth's radius, the Earth can be approximated by a plane horizontal half space. In this case, electromagnetic energy is reflected with close to 100 percent efficiency from the Earth's surface. This implies that the total horizontal field is twice the source field when the source is above the satellite, but is reduced to values which are much smaller than the source field when the source is below the satellite. This latter effect tends to enhance the signature of gross electrical discontinuities in the lithosphere when observed at satellite altitudes.

Some diagnostic interpretations from railgun plasma profile experiments

NASA Astrophysics Data System (ADS)

Stainsby, D. F.; Bedford, A. J.

1984-03-01

Some aspects of a railgun experimental series to investigate plasma profiles are reviewed. Certain diagnostic records clearly show plasma leakage past the projectile, and correspondence between various in-bore events and muzzle voltage. A muzzle flash detector is shown to have a useful role as a plasma diagnostic tool.

Development of software for geodynamic processes monitoring system

NASA Astrophysics Data System (ADS)

Kabanov, M. M.; Kapustin, S. N.; Gordeev, V. F.; Botygin, I. A.; Tartakovsky, V. A.

2017-11-01

This article justifies the usage of natural pulsed electromagnetic Earth's noises logging method for mapping anomalies of strain-stress state of Earth's crust. The methods and technologies for gathering, processing and systematization of data gathered by ground multi-channel geophysical loggers for monitoring geomagnetic situation have been experimentally tested, and software had been developed. The data was consolidated in a network storage and can be accessed without using any specialized client software. The article proposes ways to distinguish global and regional small-scale time-space variations of Earth's natural electromagnetic field. For research purposes, the software provides a way to export data for any given period of time for any loggers and displays measurement data charts for selected set of stations.

Natural orbital environment definition guidelines for use in aerospace vehicle development

NASA Technical Reports Server (NTRS)

Anderson, B. Jeffrey (Editor); Smith, Robert E. (Compiler)

1994-01-01

This document provides definitions of the natural near-Earth space environment suitable for use in the initial development/design phase of any space vehicle. The natural environment includes the neutral atmosphere, plasma, charged particle radiation, electromagnetic radiation (EMR), meteoroids, orbital debris, magnetic field, physical and thermal constants, and gravitational field. Communications and other unmanned satellites operate in geosynchronous-Earth orbit (GEO); therefore, some data are given for GEO, but emphasis is on altitudes from 200 km to 1000 km (low-Earth orbit (LEO)). This document does not cover the induced environment of other effects resulting from presence of the space vehicle. Manmade factors are included as part of the ambient natural environment; i.e., orbital debris and radio frequency (RF) noise generated on Earth, because they are not caused by the presence of the space vehicle but form part of the ambient environment that the space vehicle experiences.

The telecommunications and data acquisition report

NASA Technical Reports Server (NTRS)

1980-01-01

Progress in the development and operations of the Deep Space Network is reported. Developments in Earth based radio technology as applied to geodynamics, astrophysics, and radio astronomy's use of the deep space stations for a radio search for extraterrestrial intelligence in the microwave region of the electromagnetic spectrum are reported.

Space shuttle electromagnetic environment experiment. Phase A: Definition study

NASA Technical Reports Server (NTRS)

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

1974-01-01

A program is discussed which develops a concept for measuring the electromagnetic environment on earth with equipment on board an orbiting space shuttle. Earlier work on spaceborne measuring experiments is reviewed, and emissions to be expected are estimated using, in part, previously gathered data. General relations among system parameters are presented, followed by a proposal on spatial and frequency scanning concepts. The methods proposed include a nadir looking measurement with small lateral scan and a circularly scanned measurement looking tangent to the earth's surface at the horizon. Antenna requirements are given, assuming frequency coverage from 400 MHz to 40 GHz. For the low frequency range, 400-1000 MHz, a processed, thinned array is proposed which will be more fully analyzed in the next phase of the program. Preliminary hardware and data processing requirements are presented.

Summary of EM launcher experiments performed at LLNL

NASA Astrophysics Data System (ADS)

Hawke, R. S.; Nellis, W. J.; Newman, G. H.; Rego, J.; Susoeff, A. R.

1986-11-01

Performance results for three railguns are summarized. The system used a helium gas-driven injector and railgun launcher to accelerate 1- and 4-g polycarbonate projectiles intact up to 6.6 and 3.0 km/sc, respectively. A 625 kJ capacitor bank powered the railgun, and an adjustable inductor provided pulse shaping and peak current control. Operation in hard and soft vacuum was reliably achieved. The diagnostic system measured the projectile position and launch velocity, verified that the projectile was launched intact in the desired direction, and identified system components where improvements could enhance performance. Flash X-ray radiography measured velocity and verified that projectiles were intact. Pre-launch projectile travel along the axis of the launcher without tilt was recorded with flash radiographs and impact impressions or holes in witness plates. The sysem performed as expected up to 4-5 km/sec but below expectations at higher velocities. Diagnostics suggest that the decreased performance was probably cuased by the restriking of a second arc in the breech of the railgun, which shunted the current from the propulsive arc.

Coronal Mass Ejections Near the Sun and in the Interplanetary Medium

NASA Technical Reports Server (NTRS)

Gopalswamy, Nat

2012-01-01

Coronal mass ejections (CMEs) are the most energetic phenomenon in the heliosphere. During solar eruptions, the released energy flows out from the Sun in the form of magnetized plasma and electromagnetic radiation. The electromagnetic radiation suddenly increases the ionization content of the ionosphere, thus impacting communication and navigation systems. The plasma clouds can drive shocks that accelerate charged particles to very high energies in the interplanetary space, which pose radiation hazard to astronauts and space systems. The plasma clouds also arrive at Earth in about two days and impact Earth's magnetosphere, producing geomagnetic storms. The magnetic storms result in a number of effects including induced currents that can disrupt power grids, railroads, and underground pipelines. This lecture presents an overview of the origin, propagation, and geospace consequences of CMEs and their interplanetary counterparts.

Repetitive resonant railgun power supply

DOEpatents

Honig, E.M.; Nunnally, W.C.

1985-06-19

A repetitive resonant railgun power supply provides energy for repetitively propelling projectiles from a pair of parallel rails. The supply comprises an energy storage capacitor, a storage inductor to form a resonant circuit with the energy storage capacitor and a magnetic switch to transfer energy between the resonant circuit and the pair of parallel rails for the propelling of projectiles.

Repetitive resonant railgun power supply

DOEpatents

Honig, Emanuel M.; Nunnally, William C.

1988-01-01

A repetitive resonant railgun power supply provides energy for repetitively propelling projectiles from a pair of parallel rails. The supply comprises an energy storage capacitor, a storage inductor to form a resonant circuit with the energy storage capacitor and a magnetic switch to transfer energy between the resonant circuit and the pair of parallel rails for the propelling of projectiles.

Railgun armature velocity improvement, SBIR phase 2

NASA Astrophysics Data System (ADS)

Thurmond, Leo E.; Bauer, David P.

1992-08-01

Railgun hypervelocity performance has not been repeatably demonstrated at velocities over 6 km/s. A significant performance limiting phenomena is the formation of secondary current paths in parallel with the main projectile accelerating plasma. A confined plasma armature technique was developed to prevent secondary armature formation. Confinement prevents loss of ionized material from the plasma armature and thereby prevents formation of a low rail-to-rail conductance. We controlled pressure in the confined armature via controlled venting through ports in the rails. Railgun tests with the confined armature show that sealing at the rail-confinement vessel interface is critical and difficult to achieve. Our tests show that during low seal leakage operation secondaries are prevented. However, maintaining good seal for the entire launch is very difficult.

Symposium on Electromagnetic Launcher Technology, 5th, Sandestin, FL, Apr. 3-5, 1990, Proceedings

NASA Astrophysics Data System (ADS)

Gooden, Clarence E.

1991-01-01

The present conference on electromagnetic accelerators (EMAs) and railguns (RGs) discusses active-current management for four-rail RGs, the design of a compulsator-drive 60-caliber RG, EMA studies with augmented rails, muzzle-shunt augmentation of conventional RGs, effect of in-bore gas on RG performance, the distributed-energy store RG, plasma diagnostics for high power ignitron development, a review of EMA armature research, RG hybrid armatures, a new solid-armature design concept, and the electrodynamics of RG plasma armatures. Also discussed is RG modeling at speed using three-dimensional finite elements, power supply technology for EMAs, rotating machine power supplies for next-generation EMAs, advanced EMA power supplies with magnetic-flux compression, metal-to-metal switches for large currents, lightweight high-effiency energy-storage transformers, hypervelocity projectile development for EMAs, structural design issues for EMA projectiles, stiff RGs, a reinforced Al conductor for cryogenic applications, mass-stabilized projectile designs for EMA launch, indictively-commutated coilguns, an actively switched pulsed induction accelerator, a plasma gun-augmented electrothermal accelerator, a symmetrical rail accelerator, and a travelling-wave synchronous coil gun.

ELF-VLF communications through the Earth Project report for calendar year 1984, revision 1

NASA Astrophysics Data System (ADS)

Buettner, H. M.; Burker, G. J.; Didwall, E. M.; Holladay, G.; Lytle, R. J.

1985-08-01

We use computer models and experiments to explore the feasibility of communication between points underground and on the Earth's surface. Emphasis is placed on ELF-VLF electromagnetic propagation through the Earth; nominally, we investigated propagation in the 200 Hz-30 kHz frequency range. The computer modeling included calculations of the fields of a point electric or magnetic source in a homogeneous half space or a stratified earth. Initial results for an insulated antenna of finite length are also considered. The experiments involved through-the-Earth transmissions at two locations in Pennsylvania, both of which had large formations of limestone. Initial results indicate that information rates as high as kbits/s may be possible for subsurface depths of 300 m or less. Accuracy of these estimates depends on the electromagnetic propagation constant of the rock, the noise characteristics, and the modulation scheme. Although a nuisance for evaluating through-the-Earth propagation, the existence of subsurface metal conductors can improve the transmission character of the site.

ELF-VLF communications through-the-Earth

NASA Astrophysics Data System (ADS)

Buettner, H. M.; Burke, G. J.; Didwall, E. M.; Holladay, G.; Lytle, R. J.

1985-06-01

We use computer models and experiments to explore the feasibility of communication between points underground and on the Earth's surface. Emphasis is placed on ELF-VLF electromagnetic propagation through the Earth; nominally, we investigated propagation in the 200 Hz-30 kHz frequency range. The computer modeling included calculations of the fields of a point electric or magnetic source in a homogeneous half space or a stratified Earth. Initial results for an insulated antenna of finite length are also considered. The experiments involved through-the-Earth transmissions at two locations in Pennsylvania, both of which had large formations of limestone. Initial results indicate that information rates as high as kbits/s may be possible for subsurface depths of 300 m or less. Accuracy of these estimates depends on the electromagnetic propagation constants of the rock, the noise characteristics, and modulation scheme. Although a nuisance for evaluating through-the-Earth propagation, the existence of subsurface metal conductors can improve the transmission character of the site.

The Unifying Principle of Coordinated Measurements in Geospace Science

NASA Astrophysics Data System (ADS)

Lotko, William

2017-04-01

Space scientists recognize geospace as a coupled dynamical system extending from the Earth's upper atmosphere, ionosphere, and magnetosphere, through interplanetary space to the Sun. The weather in geospace describes variability in the electromagnetic fields, particle radiation, plasmas, and gases permeating it, usually in response to solar disturbances. Severe space weather poses a significant threat to human activities in space and to modern technological systems deployed both in space and at Earth. The challenge of characterizing and predicting space weather requires widely distributed, coordinated observations. Partnerships among government agencies, international consortia, and the private sector are developing creative solutions to address this challenge. This brief commentary highlights some of the coordinated measurements and data systems that are unifying knowledge of the geospace environment.

Research in space physics at the University of Iowa. [astronomical observatories, spaceborne astronomy, satellite observation

NASA Technical Reports Server (NTRS)

Vanallen, J. A.

1974-01-01

Various research projects in space physics are summarized. Emphasis is placed on: (1) the study of energetic particles in outer space and their relationships to electric, magnetic, and electromagnetic fields associated with the earth, the sun, the moon, the planets, and interplanetary medium; (2) observational work on satellites of the earth and the moon, and planetary and interplanetary spacecraft; (3) phenomenological analysis and interpretation; (4) observational work by ground based radio-astronomical and optical techniques; and (5) theoretical problems in plasma physics. Specific fields of current investigations are summarized.

Non-linear processes in the Earth atmosphere boundary layer

NASA Astrophysics Data System (ADS)

Grunskaya, Lubov; Valery, Isakevich; Dmitry, Rubay

2013-04-01

The work is connected with studying electromagnetic fields in the resonator Earth-Ionosphere. There is studied the interconnection of tide processes of geophysical and astrophysical origin with the Earth electromagnetic fields. On account of non-linear property of the resonator Earth-Ionosphere the tides (moon and astrophysical tides) in the electromagnetic Earth fields are kinds of polyharmonic nature. It is impossible to detect such non-linear processes with the help of the classical spectral analysis. Therefore to extract tide processes in the electromagnetic fields, the method of covariance matrix eigen vectors is used. Experimental investigations of electromagnetic fields in the atmosphere boundary layer are done at the distance spaced stations, situated on Vladimir State University test ground, at Main Geophysical Observatory (St. Petersburg), on Kamchatka pen., on Lake Baikal. In 2012 there was continued to operate the multichannel synchronic monitoring system of electrical and geomagnetic fields at the spaced apart stations: VSU physical experimental proving ground; the station of the Institute of Solar and Terrestrial Physics of Russian Academy of Science (RAS) at Lake Baikal; the station of the Institute of volcanology and seismology of RAS in Paratunka; the station in Obninsk on the base of the scientific and production society "Typhoon". Such investigations turned out to be possible after developing the method of scanning experimental signal of electromagnetic field into non- correlated components. There was used a method of the analysis of the eigen vectors ofthe time series covariance matrix for exposing influence of the moon tides on Ez. The method allows to distribute an experimental signal into non-correlated periodicities. The present method is effective just in the situation when energetical deposit because of possible influence of moon tides upon the electromagnetic fields is little. There have been developed and realized in program components in the form of PAS instruments of processes of geophysical and man-triggered nature; to predict the presence of the features of geophysical nature in the electromagnetic field of the atmosphere boundary surface layer; to study dynamics the analyzed signals coming from the geophysical and man-triggered sources in the electrical and magnetic fields of the atmosphere boundary surface layer; to expose changes of the investigated time series in the periods preceding the appearance of the predicted phenomena; to form clusters of the time series being the features of the predicted events. On the base of the exposed clusters of the time series there have been built the predicting rules allowing to coordinate the probability of appearing the groups of the occurred events. The work is carried out with supporting of Program FPP #14.B37.210668, FPP #5.2071.2011, RFBR #11-05-97518.

Observations and Impact Assessments of Extreme Space Weather Events

NASA Astrophysics Data System (ADS)

Baker, D. N.

2007-05-01

"Space weather" refers to conditions on the Sun, in the solar wind, and in Earth`s magnetosphere, ionosphere, and thermosphere. Activity on the Sun such as solar flares and coronal mass ejections can lead to high levels of radiation in space and can cause major magnetic storms at the Earth. Space radiation can come as energetic particles or as electromagnetic emissions. Adverse conditions in the near-Earth space environment can cause disruption of satellite operations, communications, navigation, and electric power distribution grids. This can lead to a variety of socioeconomic losses. Astronauts and airline passengers exposed to high levels of radiation are also at risk. Society`s vulnerability to space weather effects is an issue of increasing concern. We are dependent on technological systems that are becoming more susceptible to space weather disturbances. We also have a permanent human presence in space with the International Space Station and the President and NASA have expressed a desire to expand our human space activities with missions to the moon and Mars. This will make space weather of even greater concern in the future. In this talk I will describe many space weather effects and will describe some of the societal and economic impacts that extreme events have had.

Evaluation of Nanocomposites for Shielding Electromagnetic Interference

DTIC Science & Technology

2011-09-01

ESD Electrostatic Discharge FAA Federal Aviation Administration FRP Fiberglass Reinforced Plastic GCR Galactic Cosmic Radiation GSM Grams...1.6 Summary This thesis presentation is divided into five chapters. Chapter I covers the background of space-based systems along with the present...amount of cosmic junk floating near earth is due to the lack of foresight and planning of early space policy. The race to space failed to implement

Magnetic Field, Force, and Inductance Computations for an Axially Symmetric Solenoid

NASA Technical Reports Server (NTRS)

Lane, John E.; Youngquist, Robert C.; Immer, Christopher D.; Simpson, James C.

2001-01-01

The pumping of liquid oxygen (LOX) by magnetic fields (B field), using an array of electromagnets, is a current topic of research and development at Kennedy Space Center, FL. Oxygen is paramagnetic so that LOX, like a ferrofluid, can be forced in the direction of a B field gradient. It is well known that liquid oxygen has a sufficient magnetic susceptibility that a strong magnetic gradient can lift it in the earth's gravitational field. It has been proposed that this phenomenon can be utilized in transporting (i.e., pumping) LOX not only on earth, but on Mars and in the weightlessness of space. In order to design and evaluate such a magnetic pumping system, it is essential to compute the magnetic and force fields, as well as inductance, of various types of electromagnets (solenoids). In this application, it is assumed that the solenoids are air wrapped, and that the current is essentially time independent.

Low voltage arc formation in railguns

DOEpatents

Hawke, R.S.

1985-08-05

A low voltage plasma arc is first established across the rails behind the projectile by switching a low voltage high current source across the rails to establish a plasma arc by vaporizing a fuse mounted on the back of the projectile, maintaining the voltage across the rails below the railgun breakdown voltage to prevent arc formation ahead of the projectile. After the plasma arc has been formed behind the projectile a discriminator switches the full energy bank across the rails to accelerate the projectile. A gas gun injector may be utilized to inject a projectile into the breech of a railgun. The invention permits the use of a gas gun or gun powder injector and an evacuated barrel without the risk of spurious arc formation in front of the projectile.

Low voltage arc formation in railguns

DOEpatents

Hawke, Ronald S.

1987-01-01

A low voltage plasma arc is first established across the rails behind the projectile by switching a low voltage high current source across the rails to establish a plasma arc by vaporizing a fuse mounted on the back of the projectile, maintaining the voltage across the rails below the railgun breakdown voltage to prevent arc formation ahead of the projectile. After the plasma arc has been formed behind the projectile a discriminator switches the full energy bank across the rails to accelerate the projectile. A gas gun injector may be utilized to inject a projectile into the breech of a railgun. The invention permits the use of a gas gun or gun powder injector and an evacuated barrel without the risk of spurious arc formation in front of the projectile.

Low voltage arc formation in railguns

DOEpatents

Hawke, R.S.

1987-11-17

A low voltage plasma arc is first established across the rails behind the projectile by switching a low voltage high current source across the rails to establish a plasma arc by vaporizing a fuse mounted on the back of the projectile, maintaining the voltage across the rails below the railgun breakdown voltage to prevent arc formation ahead of the projectile. After the plasma arc has been formed behind the projectile a discriminator switches the full energy bank across the rails to accelerate the projectile. A gas gun injector may be utilized to inject a projectile into the breech of a railgun. The invention permits the use of a gas gun or gun powder injector and an evacuated barrel without the risk of spurious arc formation in front of the projectile. 2 figs.

Space Weather Prediction

DTIC Science & Technology

2014-10-31

range of solar emissions (electromagnetic, high energy particles, and plasma ) on time scales ranging from hours/days to months/years depending on the...slower than the speed of light and take a finite time to exceed an intensity threshold of operational interest at Earth . Because of the long time scale ...typically 1-3 days) for geoeffective plasma disturbances associated with Coronal Mass Ejections (CMEs) to reach Earth , geomagnetic storm

Sample levitation and melt in microgravity

NASA Technical Reports Server (NTRS)

Moynihan, Philip I. (Inventor)

1990-01-01

A system is described for maintaining a sample material in a molten state and away from the walls of a container in a microgravity environment, as in a space vehicle. A plurality of sources of electromagnetic radiation, such as an infrared wavelength, are spaced about the object, with the total net electromagnetic radiation applied to the object being sufficient to maintain it in a molten state, and with the vector sum of the applied radiation being in a direction to maintain the sample close to a predetermined location away from the walls of a container surrounding the sample. For a processing system in a space vehicle that orbits the Earth, the net radiation vector is opposite the velocity of the orbiting vehicle.

Sample levitation and melt in microgravity

NASA Technical Reports Server (NTRS)

Moynihan, Philip I. (Inventor)

1987-01-01

A system is described for maintaining a sample material in a molten state and away from the walls of a container in a microgravity environment, as in a space vehicle. A plurality of sources of electromagnetic radiation, such as of an infrared wavelength, are spaced about the object, with the total net electromagnetic radiation applied to the object being sufficient to maintain it in a molten state, and with the vector sum of the applied radiation being in a direction to maintain the sample close to a predetermined location away from the walls of a container surrounding the sample. For a processing system in a space vehicle that orbits the Earth, the net radiation vector is opposite the velocity of the orbiting vehicle.

Numerical predictions of EML (electromagnetic launcher) system performance

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

Schnurr, N.M.; Kerrisk, J.F.; Davidson, R.F.

1987-01-01

The performance of an electromagnetic launcher (EML) depends on a large number of parameters, including the characteristics of the power supply, rail geometry, rail and insulator material properties, injection velocity, and projectile mass. EML system performance is frequently limited by structural or thermal effects in the launcher (railgun). A series of computer codes has been developed at the Los Alamos National Laboratory to predict EML system performance and to determine the structural and thermal constraints on barrel design. These codes include FLD, a two-dimensional electrostatic code used to calculate the high-frequency inductance gradient and surface current density distribution for themore » rails; TOPAZRG, a two-dimensional finite-element code that simultaneously analyzes thermal and electromagnetic diffusion in the rails; and LARGE, a code that predicts the performance of the entire EML system. Trhe NIKE2D code, developed at the Lawrence Livermore National Laboratory, is used to perform structural analyses of the rails. These codes have been instrumental in the design of the Lethality Test System (LTS) at Los Alamos, which has an ultimate goal of accelerating a 30-g projectile to a velocity of 15 km/s. The capabilities of the individual codes and the coupling of these codes to perform a comprehensive analysis is discussed in relation to the LTS design. Numerical predictions are compared with experimental data and presented for the LTS prototype tests.« less

High performance railgun barrels for laboratory use

NASA Astrophysics Data System (ADS)

Bauer, David P.; Newman, Duane C.

1993-01-01

High performance low-cost, laboratory railgun barrels are now available, comprised of an inherently stiff containment structure which surrounds the bore components machined from 'off the-shelf' materials. The shape of the containment structure was selected to make the barrel inherently stiff. The structure consists of stainless steel laminations which do not compromise the electrical efficiency of the railgun. The modular design enhances the utility of the barrel, as it is easy to service between shots, and can be 're-cored' to produce different configurations and sizes using the same structure. We have produced barrels ranging from 15 mm to 90 mm square bore, a 30 mm round bore, and in lengths varying from 0.25 meters to 10 meters long. Successful tests with both plasma and solid metal armatures have demonstrated the versatility and performance of this design.

Science Enabled by the Ares V: A Large Monolithic Telescope Placed at the Second Sun-Earth Lagrange Point

NASA Technical Reports Server (NTRS)

Hopkins, Randall C.; Stahl, H. Philip

2007-01-01

The payload mass and volume capabilities of the planned Ares V launch vehicle provide the science community with unprecedented opportunities to place large science payloads into low earth orbit and beyond. One example, the outcome of a recent study conducted at the NASA Marshall Space Flight Center, is a large, monolithic telescope with a primary mirror diameter of 6.2 meters placed into a halo orbit about the second Sun-Earth Lagrange point, or L2, approximately 1.5 million kin beyond Earth's orbit. Operating in the visible and ultraviolet regions of the electromagnetic spectrum, such a large telescope would allow astronomers to detect bio-signatures and characterize the atmospheres of transiting exoplanets, provide high resolution imaging three or more times better than the Hubble Space Telescope and the James Webb Space Telescope, and observe the ultraviolet light from warm baryonic matter.

Solidification of Undercooled Melts of Al-Based Alloys on Earth and in Space

NASA Astrophysics Data System (ADS)

Herlach, Dieter M.; Burggraf, Stefan; Galenko, Peter; Gandin, Charles-André; Garcia-Escorial, Asuncion; Henein, Hani; Karrasch, Christian; Mullis, Andrew; Rettenmayr, Markus; Valloton, Jonas

2017-08-01

Containerless processing of droplets and drops by atomization and electromagnetic levitation are applied to undercool metallic melts and alloys prior to solidification. Heterogeneous nucleation on crucible walls is completely avoided giving access to large undercoolings. Experiments are performed both under terrestrial (1 g) conditions and in reduced gravity ( µg) as well. Microgravity conditions are realized by the free fall of small droplets during atomization of a spray of droplets, individual drops in a drop tube and by electromagnetic levitation of drops during parabolic flights, sounding rocket missions, and using the electro-magnetic levitator multi-user facility on board the International Space Station. The comparison of both sets of experiments in 1 g and µg leads to an estimation of the influence of forced convection on dendrite growth kinetics and microstructure evolution.

Erosion measurement techniques for plasma-driven railgun barrels

NASA Astrophysics Data System (ADS)

Jamison, K. A.; Niiler, Andrus

1987-04-01

Plasma-driven railguns are now in operation at several locations throughout the world. All share common problems in barrel erosion arising from the fact that the bore surface must contain a high temperature plasma armature which transmits the acceleration force to a projectile. The plasma temperature at the core of the armature is estimated to be 30 000 K or higher. Such conditions are erosive to most materials even when the exposure time is 100 μs or less. We have adapted two accelerator based techniques to aid in the study of this erosion. The first technique involves the collection and analysis of material ablated and left behind by the plasma. This analysis is based on the unfolding of the Rutherford backscattered (RBS) spectra of 1 MeV deuterons incident on residue collected from a railgun bore. The second technique is an erosion measurement involving thin layer activation (TLA) of surfaces. In this process, the copper rail surface is activated by 2.4 MeV protons creating a relatively thin (3 m) layer sparsely seeded with a long lived zinc isotope. Monitoring the decay of the activated sample before and after a firing can detect surface wear of about 0. 1 m. Results from the RBS and TLA experiments on the BRL plasma driven railgun are described.

Focusing experiments in plasma coaxial railguns

NASA Astrophysics Data System (ADS)

Driga, M. D.; Cook, R. W.; Thelen, R. F.

1986-11-01

Results are reported from experiments on focusing of plasma fired from a coaxial electromagnetic gun (CEMG). The plasma used, obtained by exploding a metallic fuse at the gun breech, comprised metal vapor, metallic liquid droplets and small chunks of solid metal. An azimuthal current, and thereby an axial field, was introduced at the breech of the CEMG by a solenoid. Previous studies indicated that the field would cause vaporized metal to form into a self-stabilizing toroidal plasma. Test shots instrumented with Languir probes and pick-up coils did not reveal the presence of toroidal plasma rings. However, post-mortem of the 30 cm rail showed that only one-third of the 3 mg Al fuse metal remained in the bore. Further, a toroidal hole was punched in a diagnostic screen at the bore exit after one shot.

Current Activities and Capabilities of the Terrestrial Environment Group at NASA's Marshall Space Flight Center

NASA Technical Reports Server (NTRS)

Roberts, Barry C.; Batts, Wade

1997-01-01

The National Aeronautics and Space Administration (NASA) designated Marshall Space Flight Center (MSFC) the center of excellence for space transportation. The Aerospace Environments and Effects (AEE) team of the Electromagnetics and Aerospace Environments Branch (EL23) in the Systems Analysis and Integration Laboratory at MSFC, supports the center of excellence designation by providing near-Earth space, deep space, planetary, and terrestrial environments expertise to projects as required. The Terrestrial Environment (TE) group within the AEE team maintains an extensive TE data base. Statistics and models derived from this data are applied to the design and development of new aerospace vehicles, as well as performance enhancement of operational vehicles such as the Space Shuttle. The TE is defined as the Earth's atmospheric environment extending from the surface to orbital insertion altitudes (approximately 90 km).

Morphology of Magnetic Storms

NASA Technical Reports Server (NTRS)

Vestine, E. H.

1961-01-01

This publication is a product of the continuing study of the properties of charged particles and fields in space being conducted by The RAND Corporation under contract No. NAS5-276 for the National Aeronautics and Space Administration. Magnetic storms, revealed by world-wide changes in the intensity of the earth's magnetic field, and emphasized by disturbances in electromagnetic communication channels, form detectable patterns on the surface of the earth and above it. The author draws together data from various times, places, and altitudes and, coupling these with what is known or inferred about the aurora, the ionosphere, and the relationship between them and the earth's radiation belts, creates a picture of what is believed to occur during a magnetic storm.

Reference earth orbital research and applications investigations (blue book). Volume 5: Communications/navigation

NASA Technical Reports Server (NTRS)

1971-01-01

The design and development of a communications/navigation facility for operation aboard space stations and space shuttles are discussed. The objectives of the facility are as follows: (1) to develop and demonstrate satellite and spacecraft technology applicable to space communications, navigation, and traffic control, (2) to optimize the use of the electromagnetic spectrum for communications and navigation satellite systems, and (3) to provide fundamental understanding of the space communications and navigation sciences to permit application of this discipline to government and industry.

Penetration of ELF currents and electromagnetic fields into the Earth's equatorial ionosphere

NASA Astrophysics Data System (ADS)

Eliasson, B.; Papadopoulos, K.

2009-10-01

The penetration of extremely low frequency (ELF) transient electromagnetic fields and associated currents in the Earth's equatorial E-region plasma is studied theoretically and numerically. In the low-frequency regime, the plasma dynamics of the E-region is characterized by helicon waves since the ions are viscously coupled to neutrals while the electrons remain mobile. For typical equatorial E-region parameters, the plasma is magnetically insulated from penetration of very long timescale magnetic fields by a thin diffusive sheath. Wave penetration driven by a vertically incident pulse localized in space and time leads to both vertical penetration and the triggering of ELF helicon/whistler waves that carry currents obliquely to the magnetic field lines. The study presented here may have relevance for ELF wave generation by lightning discharges and seismic activity and can lead to new concepts in ELF/ULF injection in the earth-ionosphere waveguide.

Plant seeds in biological research in space

NASA Technical Reports Server (NTRS)

Miller, A. T.

1982-01-01

Data of 15 years of space flight and laboratory tests of plant seeds of 20 species, mainly on the combined and separate effects of launch vibration, ionizing radiation and weightlessness, are surveyed. It is concluded that plants do not show a pronounced response to space flight factors. Conditions of return to Earth, the number of heavy cosmic ray particles striking biological targets and effects of change in magnetic an electromagnetic fields have been little studied, and that more study of growing plants in space is needed.

Mechanisms for the Dissipation of Alfven Waves in Near-Earth Space Plasma

NASA Technical Reports Server (NTRS)

Singh, Nagendra; Khazanov, George; Krivorutsky, E. N.; Davis, John M. (Technical Monitor)

2002-01-01

Alfven waves are a major mechanism for the transport of electromagnetic energy from the distant part of the magnetosphere to the near-Earth space. This is especially true for the auroral and polar regions of the Earth. However, the mechanisms for their dissipation have remained illusive. One of the mechanisms is the formation of double layers when the current associated with Alfven waves in the inertial regime interact with density cavities, which either are generated nonlinearly by the waves themselves or are a part of the ambient plasma turbulence. Depending on the strength of the cavities, weak and strong double layers could form. Such double layers are transient; their lifetimes depend on that of the cavities. Thus they impulsively accelerate ions and electrons. Another mechanism is the resonant absorption of broadband Alfven- wave noise by the ions at the ion cyclotron frequencies. But this resonant absorption may not be possible for the very low frequency waves, and it may be more suited for electromagnetic ion cyclotron waves. A third mechanism is the excitation of secondary waves by the drifts of electrons and ions in the Alfven wave fields. It is found that under suitable conditions, the relative drifts between different ion species and/or between electrons and ions are large enough to drive lower hybrid waves, which could cause transverse accelerations of ions and parallel accelerations of electrons. This mechanism is being further studied by means of kinetic simulations using 2.5- and 3-D particle-in-cell codes. The ongoing modeling efforts on space weather require quantitative estimates of energy inputs of various kinds, including the electromagnetic energy. Our studies described here contribute to the methods of determining the estimates of the input from ubiquitous Alfven waves.

Distributed energy store powered railguns for hypervelocity launch

NASA Astrophysics Data System (ADS)

Maas, Brian L.; Bauer, David P.; Marshall, Richard A.

1993-01-01

Highly distributed power supplies are proposed as a basis for current difficulties with hypervelocity railgun power-supply compactness. This distributed power supply configuration reduces rail-to-rail voltage behind the main armature, thereby reducing the tendency for secondary armature current formation; secondary current elimination is essential for achieving the efficiencies associated with muzzle velocity above 6 km/sec. Attention is given to analytical and experimental results for two distributed energy storage schemes.

Skylab

NASA Image and Video Library

1970-01-01

This 1970 photograph shows Skylab's Infrared Spectrometer Viewfinder Tracking System, a major component of an Earth Resources Experiment Package (EREP). It was designed to evaluate Earth resources sensors for specific regions of the the visible and infrared spectra and assess the value of real time identification of ground sites. The overall purpose of the EREP was to test the use of sensors that operated in the visible, infrared, and microwave portions of the electromagnetic spectrum to monitor and study Earth resources. The Marshall Space Flight Center had program management responsibility for the development of Skylab hardware and experiments.

The telecommunications and data acquisition report

NASA Technical Reports Server (NTRS)

Renzetti, N. A. (Editor)

1982-01-01

Progress in the development and operations of the Deep Space Network is reported. Developments in Earth-based radio technology as applied to other research programs are also reported. These programs include geodynamics, astrophysics, and radio searching for extraterrestrial intelligence in the microwave region of the electromagnetic spectrum.

The Telecommunications and Data Acquisition report

NASA Technical Reports Server (NTRS)

Renzetti, N. A. (Editor)

1981-01-01

Progress in the development and operations of the Deep Space Network is reported including develoments in Earth-based radio technology as applied to other research programs. These programs are: geodynamics, astrophysics, and the radio search for extraterrestrial intelligence in the microwave region of the electromagnetic spectrum.

Qualification of Electrical Ground Support Equipment for New Space Programs

NASA Technical Reports Server (NTRS)

SotoToro, Felix A.; Vu, Bruce T.; Hamilton, Mark S.

2011-01-01

With the Space Shuttle program coming to an end, the National Aeronautics and Space Administration (NASA) is moving to a new space flight program that will allow expeditions beyond low earth orbit. The space vehicles required to comply with these missions will be carrying heavy payloads. This implies that the Earth departure stage capabilities must be of higher magnitudes, given the current propulsion technology. The engineering design of the new flight hardware comes with some structural, thermal, propulsion and other subsystems' challenges. Meanwhile, the necessary ground support equipment (GSE) used to test, validate, verify and process the flight hardware must withstand the new program specifications. This paper intends to provide the qualification considerations during implementation of new electrical GSE for space programs. A team of engineers was formed to embark on this task, and facilitate the logistics process and ensure that the electrical, mechanical and fluids subsystems conduct the proper level of testing. Ultimately, each subsystem must certify that each piece of ground support equipment used in the field is capable of withstanding the strenuous vibration, acoustics, environmental, thermal and Electromagnetic Interference (EMf) levels experienced during pre-launch, launch and post-launch activities. The benefits of capturing and sharing these findings will provide technical, cost savings and schedule impacts infon11ation to both the technical and management community. Keywords: Qualification; Testing; Ground Support Equipment; Electromagnetic Interference Testing; Vibration Testing; Acoustic Testing; Power Spectral Density.

The telecommunications and data acquisition report

NASA Technical Reports Server (NTRS)

Renzetti, N. A. (Editor)

1981-01-01

Deep Space Network operations, engineering, and implementation are reported. Developments in Earth-based radiotechnology as applied to other research programs in the fields of Geodynamics, Astrophysics, and programs related to radio searchers (instrumentation and methods) in extraterrestrial areas in the microwave region of the electromagnetic spectrum are also presented.

Use of electromagnetic-terrain conductivity and DC-resistivity profiling techniques for bedrock characterization at the 15th-of-May City extension, Cairo, Egypt

NASA Astrophysics Data System (ADS)

Aly, Said A.; Farag, Karam S. I.; Atya, Magdy A.; Badr, Mohamed A. M.

2018-06-01

A joint multi-spacing electromagnetic-terrain conductivity meter and DC-resistivity horizontal profiling survey was conducted at the anticipated eastern extensional area of the 15th-of-May City, southeastern Cairo, Egypt. The main objective of the survey was to highlight the applicability, efficiency, and reliability of utilizing such non-invasive surface techniques in a field like geologic mapping, and hence to image both the vertical and lateral electrical resistivity structures of the subsurface bedrock. Consequently, a total of reliable 6 multi-spacing electromagnetic-terrain conductivity meter and 7 DC-resistivity horizontal profiles were carried out between August 2016 and February 2017. All data sets were transformed-inverted extensively and consistently in terms of two-dimensional (2D) electrical resistivity smoothed-earth models. They could be used effectively and inexpensively to interpret the area's bedrock geologic sequence using the encountered consecutive electrically resistive and conductive anomalies. Notably, the encountered subsurface electrical resistivity structures, below all surveying profiles, are correlated well with the mapped geological faults in the field. They even could provide a useful understanding of their faulting fashion. Absolute resistivity values were not necessarily diagnostic, but their vertical and lateral variations could provide more diagnostic information about the layer lateral extensions and thicknesses, and hence suggested reliable geo-electric earth models. The study demonstrated that a detailed multi-spacing electromagnetic-terrain conductivity meter and DC-resistivity horizontal profiling survey can help design an optimal geotechnical investigative program, not only for the whole eastern extensional area of the 15th-of-May City, but also for the other new urban communities within the Egyptian desert.

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

Aldridge, David F.; Bartel, Lewis C.

Program LETS calculates the electric current distribution (in space and time) along an electrically energized steel-cased geologic borehole situated within the subsurface earth. The borehole is modeled as an electrical transmission line that “leaks” current into the surrounding geology. Parameters pertinent to the transmission line current calculation (i.e., series resistance and inductance, shunt capacitance and conductance) are obtained by sampling the electromagnetic (EM) properties of a three-dimensional (3D) geologic earth model along a (possibly deviated) well track.

Effects of Space Weather on Geosynchronous Electromagnetic Spacecraft Perturbations Using Statistical Fluxes

NASA Astrophysics Data System (ADS)

Hughes, J.; Schaub, H.

2017-12-01

Spacecraft can charge to very negative voltages at GEO due to interactions with the space plasma. This can cause arcing which can damage spacecraft electronics or solar panels. Recently, it has been suggested that spacecraft charging may lead to orbital perturbations which change the orbits of lightweight uncontrolled debris orbits significantly. The motions of High Area to Mass Ratio objects are not well explained with just perturbations from Solar Radiation Pressure (SRP) and earth, moon, and sun gravity. A charged spacecraft will experience a Lorentz force as the spacecraft moves relative to Earth's magnetic field, as well as a Lorentz torque and eddy current torques if the object is rotating. Prior work assuming a constant "worst case" voltage has shown that Lorentz and eddy torques can cause quite large orbital changes by rotating the object to experience more or less SRP. For some objects, including or neglecting these electromagnetic torques can lead to differences of thousands of kilometers after only two orbits. This paper will further investigate the effects of electromagnetic perturbations by using a charging model that uses measured flux distributions to better simulate natural charging. This differs from prior work which used a constant voltage or Maxwellian distributions. This is done to a calm space weather case of Kp = 2 and a stormy case where Kp = 8. Preliminary analysis suggests that electrostatics will still cause large orbital changes even with the more realistic charging model.

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

NASA Astrophysics Data System (ADS)

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

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

A fully coupled flow simulation around spacecraft in low earth orbit

NASA Technical Reports Server (NTRS)

Justiz, C. R.; Sega, R. M.

1991-01-01

The primary objective of this investigation is to provide a full flow simulation of a spacecraft in low earth orbit (LEO). Due to the nature of the environment, the simulation includes the highly coupled effects of neutral particle flow, free stream plasma flow, nonequilibrium gas dynamics effects, spacecraft charging and electromagnetic field effects. Emphasis is placed on the near wake phenomenon and will be verified in space by the Wake Shield Facility (WSF) and developed for application to Space Station conditions as well as for other spacecraft. The WSF is a metallic disk-type structure that will provide a controlled space platform for highly accurate measurements. Preliminary results are presented for a full flow around a metallic disk.

Energy Transfer in the Earth-Sun System

NASA Astrophysics Data System (ADS)

Lui, A. T. Y.; Kamide, Y.

2007-02-01

Conference on Earth-Sun System Exploration: Energy Transfer; Kailua-Kona, Hawaii, USA, 16-20 January 2006; The goal of this conference, which was supported by several agencies and organizations, was to provide a forum for physicists engaged in the Earth-Sun system as well as in laboratory experiments to discuss and exchange knowledge and ideas on physical processes involving energy transfer. The motivation of the conference stemmed from the following realization: Space assets form an important fabric of our society, performing functions such as television broadcasting, cell- phone communication, navigation, and remote monitoring of tropospheric weather. There is increasing awareness of how much our daily activities can be adversely affected by space disturbances stretching all the way back to the Sun. In some of these energetic phenomena, energy in various forms can propagate long distances from the solar surface to the interplanetary medium and eventually to the Earth's immediate space environment, namely, its magnetosphere, ionosphere, and thermosphere. In addition, transformation of energy can take place in these space disturbances, allowing charged-particle energy to be transformed to electromagnetic energy or vice versa. In- depth understanding of energy transformation and transmission in the Earth-Sun system will foster the identification of physical processes responsible for space disturbances and the prediction of their occurrences and effects. Participants came from 15 countries.

An Investigation of the Static Force Balance of a Model Railgun

DTIC Science & Technology

2007-06-01

this simple circuit diagram two 950 CCA batteries are passed through a variable resistor (R1) to limit the current applied to the model railgun (R2...of a known value and placed a voltmeter across the resistor . For additional protection in these early trials we inserted an equivalent 1kA fuse...our variable resistor . Current then passed through the resistor into the model gun, through a volt-meter with a known resistance, into a kilo-amp

The Railgun and Its Power Source,

DTIC Science & Technology

1987-06-01

34railguns") and to investigate in detail a power source which seemed especially suited to them. Background Figure I shows the principle of the raligun. x ...from the integral of J x B through the volume where the current crosses between the rails, and where J is the current density and B is the magnetic...force is yielded by: 3 F - - (1.2) x ax where W denotes energy and the partial derivative notation indicates that the portion of the energy change

Acceleration of an Initially Moving Projectile: Velocity-Injected Railguns and Their Effect on Pulsed Power

DTIC Science & Technology

2009-07-01

section 2, the propellant gun is assessed from existing experimental data. In section 3, circuit analysis is used to model the railgun with a 2 launch...An Empirical Model for Plasma Armature Voltage. IEEE Transactions on Magnetics 1991, 27, 283–288. 11. Elder, D. The First Generation in the...1 US ARMY MISSLE COMMAND AMSRD AMR W W C MCCORKLE 5400 FOWLER RD REDSTONE ARSENAL AL 35898-5240 1 US ARMY TACOM TARDEC AMSTA TR

Coffee-can-sized spacecraft

NASA Technical Reports Server (NTRS)

Jones, Ross M.

1988-01-01

The current status and potential scientific applications of intelligent 1-5-kg projectiles being developed by SDIO and DARPA for military missions are discussed. The importance of advanced microelectronics for such small spacecraft is stressed, and it is pointed out that both chemical rockets and EM launchers are currently under consideration for these lightweight exoatmospheric projectiles (LEAPs). Long-duration power supply is identified as the primary technological change required if LEAPs are to be used for interplanetary scientific missions, and the design concept of a solar-powered space-based railgun to accelerate LEAPs on such missions is considered.

Estimation of the Lithospheric Component Share in the Earth Natural Pulsed Electromagnetic Field Structure

NASA Astrophysics Data System (ADS)

Malyshkov, S. Y.; Gordeev, V. F.; Polyvach, V. I.; Shtalin, S. G.; Pustovalov, K. N.

2017-04-01

Article describes the results of the atmosphere and Earth’s crust climatic and ecological parameters integrated monitoring. The estimation is made for lithospheric component share in the Earth natural pulsed electromagnetic field structure. To estimate lithospheric component we performed a round-the-clock monitoring of the Earth natural pulsed electromagnetic field background variations at the experiment location and measured the Earth natural pulsed electromagnetic field under electric shields. Natural materials in a natural environment were used for shielding, specifically lakes with varying parameters of water conductivity. Skin effect was used in the experiment - it is the tendency of electromagnetic waves amplitude to decrease with greater depths in the conductor. Atmospheric and lithospheric component the Earth natural pulsed electromagnetic field data recorded on terrain was compared against the recorded data with atmosphere component decayed by an electric shield. In summary we have demonstrated in the experiment that thunderstorm discharge originating electromagnetic field decay corresponds to the decay calculated using Maxwell equations. In the absence of close lightning strikes the ratio of field intensity recorded on terrain to shielded field intensity is inconsistent with the ratio calculated for atmospheric sources, that confirms there is a lithospheric component present to the Earth natural pulsed electromagnetic field.

The analysis and modeling of the ARDEC 2.5 km/s 20-mm plasma railgun shot

NASA Astrophysics Data System (ADS)

Sink, D. A.; Chang, D. I.; Davis, A.; Colombo, G.; Hildenbrand, D. J.

1993-01-01

The 20-mm round-bore plasma railgun was successfully fired at the ARDEC electric gun facility. The 4-m gun with copper rails and alumina composite insulators was operated using a light-gas gun injector to start the projectile, already located in the gun, moving prior to the introduction of current. Current from the EMACK homopolar generator (HPG) was commutated into the gun by an explosively-actuated opening switch. The muzzle velocity was recorded by breakwires and flash X-rays at 2.5 km/s. B-dot sensors, rail current Rogowski coils, and breech and muzzle voltage measurements provided data on the in-bore dynamics of the armature. Post-shot analysis using the ARMRAIL (ARMature Physics and RAILgun Performance Model) code successfully provided calculations reproducing all the main features of the data. Models account for the observed secondary arcs present throughout the shot and the basis for the code and physics modeling is given.

The AMT maglev test sled -- EML weapons technology transition to transportation

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

Schaaf, J.C. Jr.; Zowarka, R.C. Jr.; Davey, K.

1997-01-01

Technology spinoffs from prior electromagnetic launcher work enhance a magnetic levitation transportation system test bed being developed by American Maglev Technology of Florida. This project uses a series wound linear DC motor and brushes to simplify the magnetic levitation propulsion system. It takes advantage of previous related work in electromagnetic launcher technology to achieve success with this innovative design. Technology and knowledge gained from developments for homopolar generators and proposed railgun arc control are key to successful performance. This contribution supports a cost effective design that is competitive with alternative concepts. Brushes transfer power from the guideway (rail) to themore » vehicle (armature) in a novel design that activates the guideway only under the vehicle, reducing power losses and guideway construction costs. The vehicle carries no power for propulsion and levitation, and acts only as a conduit for the power through the high speed brushes. Brush selection and performance is based on previous EML homopolar generator research. A counterpulse circuit, first introduced in an early EML conference, is used to suppress arcing on the trailing brush and to transfer inductive energy to the next propulsion coil. Isolated static lift and preliminary propulsion tests have been completed, and integrated propulsion and lift tests are scheduled in early 1996.« less

KSC-2012-3472

NASA Image and Video Library

2012-06-23

CAPE CANAVERAL, Fla. – Inside the Astrotech payload processing facility near NASA’s Kennedy Space Center in Florida, technicians line up the Radiation Belt Storm Probes, or RBSP, spacecraft A over an electromagnetic source in order to perform a magnetic swing test. The magnetic swing test is performed to characterize the magnetic signature of the spacecraft so that when it is taking measurements with its sensors in space scientists can subtract out background noise from the spacecraft itself. NASA’s RBSP mission will help us understand the sun’s influence on Earth and near-Earth space by studying the Earth’s radiation belts on various scales of space and time. RBSP will begin its mission of exploration of Earth’s Van Allen radiation belts and the extremes of space weather after its launch aboard a United Launch Alliance Atlas V rocket. Launch is targeted for Aug. 23. For more information, visit http://www.nasa.gov/rbsp. Photo credit: NASA/Charisse Nahser

KSC-2012-3474

NASA Image and Video Library

2012-06-23

CAPE CANAVERAL, Fla. – Inside the Astrotech payload processing facility near NASA’s Kennedy Space Center in Florida, technicians line up the Radiation Belt Storm Probes, or RBSP, spacecraft A over an electromagnetic source in order to perform a magnetic swing test. The magnetic swing test is performed to characterize the magnetic signature of the spacecraft so that when it is taking measurements with its sensors in space scientists can subtract out background noise from the spacecraft itself. NASA’s RBSP mission will help us understand the sun’s influence on Earth and near-Earth space by studying the Earth’s radiation belts on various scales of space and time. RBSP will begin its mission of exploration of Earth’s Van Allen radiation belts and the extremes of space weather after its launch aboard a United Launch Alliance Atlas V rocket. Launch is targeted for Aug. 23. For more information, visit http://www.nasa.gov/rbsp. Photo credit: NASA/Charisse Nahser

KSC-2012-3471

NASA Image and Video Library

2012-06-23

CAPE CANAVERAL, Fla. – Inside the Astrotech payload processing facility near NASA’s Kennedy Space Center in Florida, technicians line up the Radiation Belt Storm Probes, or RBSP, spacecraft A over an electromagnetic source in order to perform a magnetic swing test. The magnetic swing test is performed to characterize the magnetic signature of the spacecraft so that when it is taking measurements with its sensors in space scientists can subtract out background noise from the spacecraft itself. NASA’s RBSP mission will help us understand the sun’s influence on Earth and near-Earth space by studying the Earth’s radiation belts on various scales of space and time. RBSP will begin its mission of exploration of Earth’s Van Allen radiation belts and the extremes of space weather after its launch aboard a United Launch Alliance Atlas V rocket. Launch is targeted for Aug. 23. For more information, visit http://www.nasa.gov/rbsp. Photo credit: NASA/Charisse Nahser

KSC-2012-3473

NASA Image and Video Library

2012-06-23

CAPE CANAVERAL, Fla. – Inside the Astrotech payload processing facility near NASA’s Kennedy Space Center in Florida, technicians line up the Radiation Belt Storm Probes, or RBSP, spacecraft A over an electromagnetic source in order to perform a magnetic swing test. The magnetic swing test is performed to characterize the magnetic signature of the spacecraft so that when it is taking measurements with its sensors in space scientists can subtract out background noise from the spacecraft itself. NASA’s RBSP mission will help us understand the sun’s influence on Earth and near-Earth space by studying the Earth’s radiation belts on various scales of space and time. RBSP will begin its mission of exploration of Earth’s Van Allen radiation belts and the extremes of space weather after its launch aboard a United Launch Alliance Atlas V rocket. Launch is targeted for Aug. 23. For more information, visit http://www.nasa.gov/rbsp. Photo credit: NASA/Charisse Nahser

KSC-2012-3470

NASA Image and Video Library

2012-06-23

CAPE CANAVERAL, Fla. – Inside the Astrotech payload processing facility near NASA’s Kennedy Space Center in Florida, technicians line up the Radiation Belt Storm Probes, or RBSP, spacecraft A over an electromagnetic source in order to perform a magnetic swing test. The magnetic swing test is performed to characterize the magnetic signature of the spacecraft so that when it is taking measurements with its sensors in space scientists can subtract out background noise from the spacecraft itself. NASA’s RBSP mission will help us understand the sun’s influence on Earth and near-Earth space by studying the Earth’s radiation belts on various scales of space and time. RBSP will begin its mission of exploration of Earth’s Van Allen radiation belts and the extremes of space weather after its launch aboard a United Launch Alliance Atlas V rocket. Launch is targeted for Aug. 23. For more information, visit http://www.nasa.gov/rbsp. Photo credit: NASA/Charisse Nahser

Multiple resonant railgun power supply

DOEpatents

Honig, E.M.; Nunnally, W.C.

1985-06-19

A multiple repetitive resonant railgun power supply provides energy for repetitively propelling projectiles from a pair of parallel rails. A plurality of serially connected paired parallel rails are powered by similar power supplies. Each supply comprises an energy storage capacitor, a storage inductor to form a resonant circuit with the energy storage capacitor and a magnetic switch to transfer energy between the resonant circuit and the pair of parallel rails for the propelling of projectiles. The multiple serial operation permits relatively small energy components to deliver overall relatively large amounts of energy to the projectiles being propelled.

Multiple resonant railgun power supply

DOEpatents

Honig, Emanuel M.; Nunnally, William C.

1988-01-01

A multiple repetitive resonant railgun power supply provides energy for repetitively propelling projectiles from a pair of parallel rails. A plurality of serially connected paired parallel rails are powered by similar power supplies. Each supply comprises an energy storage capacitor, a storage inductor to form a resonant circuit with the energy storage capacitor and a magnetic switch to transfer energy between the resonant circuit and the pair of parallel rails for the propelling of projectiles. The multiple serial operation permits relatively small energy components to deliver overall relatively large amounts of energy to the projectiles being propelled.

A strategy for the observation of volcanism on Earth from space.

PubMed

Wadge, G

2003-01-15

Heat, strain, topography and atmospheric emissions associated with volcanism are well observed by satellites orbiting the Earth. Gravity and electromagnetic transients from volcanoes may also prove to be measurable from space. The nature of eruptions means that the best strategy for measuring their dynamic properties remotely from space is to employ two modes with different spatial and temporal samplings: eruption mode and background mode. Such observational programmes are best carried out at local or regional volcano observatories by coupling them with numerical models of volcanic processes. Eventually, such models could become multi-process, operational forecast models that assimilate the remote and other observables to constrain their uncertainties. The threat posed by very large magnitude explosive eruptions is global and best addressed by a spaceborne observational programme with a global remit.

Pitch-angle diffusion of electrons through growing and propagating along a magnetic field electromagnetic wave in Earth's radiation belts

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

Choi, C.-R., E-mail: crchoi@kaist.ac.kr; Dokgo, K.; Min, K.-W.

The diffusion of electrons via a linearly polarized, growing electromagnetic (EM) wave propagating along a uniform magnetic field is investigated. The diffusion of electrons that interact with the growing EM wave is investigated through the autocorrelation function of the parallel electron acceleration in several tens of electron gyration timescales, which is a relatively short time compared with the bounce time of electrons between two mirror points in Earth's radiation belts. Furthermore, the pitch-angle diffusion coefficient is derived for the resonant and non-resonant electrons, and the effect of the wave growth on the electron diffusion is discussed. The results can bemore » applied to other problems related to local acceleration or the heating of electrons in space plasmas, such as in the radiation belts.« less

Spectroscopic measurements of muzzle flash plasma

NASA Astrophysics Data System (ADS)

Uglum, J. R.

1986-11-01

The experimental apparatus and sample data for the muzzle flash plasma of a laboratory-scale railgun are described. Theoretical predictions for the railgun system configuration used indicated that 24 kJ of energy would be dissipated by the muzzle flash. Spectral data were recorded with a spectrograph sensing through a slit and a PIN diode, the latter to obtain temporal resolution in the data. The tests featured a plastic projectile with an Al foil armature. The measurements identified Cu as the dominant flash material, ablated from the rails in the barrel.

The Telecommunications and Data Acquisition

NASA Technical Reports Server (NTRS)

Renzetti, N. A. (Editor)

1981-01-01

Progress in the development and operations of the Deep Space Network is reported including developments in Earth based radio technology as applied to other research programs. These programs include application of radio interferometry at microwave frequencies to geodetic measurements and geodynamics, use of deep space stations individually and in pairs as an interferometer by radio astronomers for astrophysics research by direct observations of radio sources, and radio search for extraterrestrial intelligence in the microwave region of the electromagnetic spectrum.

Instructional computing in space physics moves ahead

NASA Astrophysics Data System (ADS)

Russell, C. T.; Omidi, N.

As the number of spacecraft stationed in the Earth's magnetosphere exponentiates and society becomes more technologically sophisticated and dependent on these spacebased resources, both the importance of space physics and the need to train people in this field will increase.Space physics is a very difficult subject for students to master. Both mechanical and electromagnetic forces are important. The treatment of problems can be very mathematical, and the scale sizes of phenomena are usually such that laboratory studies become impossible, and experimentation, when possible at all, must be carried out in deep space. Fortunately, computers have evolved to the point that they are able to greatly facilitate instruction in space physics.

Skylab

NASA Image and Video Library

1970-01-01

This 1970 photograph shows Skylab's Multispectral Scanner, one of the major components of an Earth Resources Experiment Package (EREP). It was designed to evaluate the on-orbit use of multispectral scanning of Earth resources. Investigators could evaluate the usefulness of spacecraft multispectral data for crop identification, vegetation mapping, soil moisture measurements, identification of contaminated areas in large bodies of water, and surface temperature mapping. The overall purpose of the EREP was to test the use of sensors that operated in the visible, infrared, and microwave portions of the electromagnetic spectrum to monitor and study Earth resources. The Marshall Space Flight Center had program management responsibility for the development of Skylab hardware and experiments.

Plasma propulsion for space applications

NASA Astrophysics Data System (ADS)

Fruchtman, Amnon

2000-04-01

The various mechanisms for plasma acceleration employed in electric propulsion of space vehicles will be described. Special attention will be given to the Hall thruster. Electric propulsion utilizes electric and magnetic fields to accelerate a propellant to a much higher velocity than chemical propulsion does, and, as a result, the required propellant mass is reduced. Because of limitations on electric power density, electric thrusters will be low thrust engines compared with chemical rockets. The large jet velocity and small thrust of electric thrusters make them most suitable for space applications such as station keeping of GEO communication satellites, low orbit drag compensation, orbit raising and interplanetary missions. The acceleration in the thruster is either thermal, electrostatic or electromagnetic. The arcjet is an electrothermal device in which the propellant is heated by an electric arc and accelerated while passing through a supersonic nozzle to a relatively low velocity. In the Pulsed Plasma Thruster a solid propellant is accelerated by a magnetic field pressure in a way that is similar in principle to pulsed acceleration of plasmas in other, very different devices, such as the railgun or the plasma opening switch. Magnetoplasmadynamic thrusters also employ magnetic field pressure for the acceleration but with a reasonable efficiency at high power only. In an ion thruster ions are extracted from a plasma through a double grid structure. Ion thrusters provide a high jet velocity but the thrust density is low due to space-charge limitations. The Hall thruster, which in recent years has enjoyed impressive progress, employs a quasi-neutral plasma, and therefore is not subject to a space-charge limit on the current. An applied radial magnetic field impedes the mobility of the electrons so that the applied potential drops across a large region inside the plasma. Methods for separately controlling the profiles of the electric and the magnetic fields will be described. The role of the sonic transition in plasma accelerators will be discussed. It will be shown that large potential drops can be localized to regions of an abrupt sonic transition in a Hall plasma. A configuration with segmented side electrodes can be used to further control the electric field profile and to increase the efficiency.

Research in space physics at the University of Iowa

NASA Technical Reports Server (NTRS)

Vanallen, J. A.

1979-01-01

Current investigations relating to energetic particles and the electric, magnetic, and electromagnetic fields associated with the earth, the sun, the moon, the planets, comets, and the interplanetary medium are reported. Primary emphasis is on observational work using a wide diversity of intruments on satellites of the earth and the moon and on planetary and interplanetary spacecraft, and on phenomenological analysis and interpretation. Secondary emphasis is given to closely related observational work by ground based radio-astronomical and optical techniques, and to theoretical problems in plasma physics as relevant to solar, planetary, and interplanetary phenomena.

The Characteristics of Electromagnetic Fields Induced by Different Type Sources

NASA Astrophysics Data System (ADS)

Di, Q.; Fu, C.; Wang, R.; Xu, C.; An, Z.

2011-12-01

Controlled source audio-frequence magnetotelluric (CSAMT) method has played an important role in the shallow exploration (less than 1.5km) in the field of resources, environment and engineering geology. In order to prospect the deeper target, one has to increase the strength of the source and offset. However, the exploration is nearly impossible for the heavy larger power transmitting source used in the deeper prospecting and mountain area. So an EM method using a fixed large power source, such as long bipole current source, two perpendicular "L" shape long bipole current source and large radius circle current source, is beginning to take shape. In order to increase the strength of the source, the length of the transmitting bipole in one direction or in perpendicular directions has to be much larger, such as L=100km, or the radius of the circle current source is much larger. The electric field strength are IL2and IL2/4π separately for long bipole source and circle current source with the same wire length. Just considering the effectiveness of source, the strength of the circle current source is larger than that of long bipole source if is large enough. However, the strength of the electromagnetic signal doesn't totally depend on the transmitting source, the effect of ionosphere on the electromagnetic (EM) field should be considered when observation is carried at a very far (about several thousands kilometers) location away from the source for the long bipole source or the large radius circle current source. We firstly calculate the electromagnetic fields with the traditional controlled source (CSEM) configuration using the integral equation (IE) code developed by our research group for a three layers earth-ionosphere model which consists of ionosphere, atmosphere and earth media. The modeling results agree well with the half space analytical results because the effect of ionosphere for this small scale source can be ignorable, which means the integral equation method is reliable and effective for modeling models including ionosphere, atmosphere and earth media. In order to discuss EM fields' characters for complicate earth-ionosphere media excited by long bipole, "L" shape bipole and circle current sources in the far-field and wave-guide zones, we modeled the frequency responses and decay characters of EM fields for three layers earth-ionosphere model. Because of the effect of ionosphere, the earth-ionosphere electromagnetic fields' decay curves with given frequency show that the fields of Ex and Hy , excited by a long bipole and "L" shape bipole, can be divided into an extra wave-guide field with slower attenuation and strong amplititude than that in half space, but the EM fields of circle current source does not show the same characteristics, ionosphere makes the amplitude of the EM field weaker for the circle current source. For this reason, it is better to use long bipole source while working in the wave-guide field with a fixed large power source.

Skylab

NASA Image and Video Library

1970-01-01

This 1970 photograph shows Skylab's Microwave Radiometer/Scatterometer and Altimeter, one of the major components for an Earth Resources Experiment Package (EREP). It was designed to study varying ocean surface, soil erosion, sea and lake ice, snow cover, seasonal vegetational changes, flooding, rainfall and soil types. The overall purpose of the EREP was to test the use of sensors that operated in the visible, infrared, and microwave portions of the electromagnetic spectrum to monitor and study Earth resources. The Marshall Space Flight Center had program management responsibility for the development of Skylab hardware and experiments.

The peculiarities of power terrestrial ELF emission in the Earth's ionosphere

NASA Astrophysics Data System (ADS)

Korepanov, Valery; Dudkin, Fedir; Pronenko, Vira; Chvach, Valery

2016-04-01

The near-Earth space is saturated with electromagnetic (EM) waves of terrestrial origin in a wide frequency range. The most powerful natural sources of EM emission are thunderstorms and triggered by them Schumann resonance (SR) radiation which is the narrowband EM noise that occurs due to the global thunderstorm activity in the Earth-ionosphere cavity in frequency range about 7-100 Hz. The considerable part of the terrestrial EM emission belongs to everyday human activity which increases year by year with unpredictable consequences. At the beginning of space exploration era it was considered that high frequency EM waves freely penetrate through the Earth's ionosphere, but the terrestrial EM emission below very low frequency range is limited by ionospheric F2 layer boundary due to great EM losses in plasma. About 40 years ago the power lines harmonic radiation (multiple of 50/60 Hz) was found at satellite observations in a few kilohertz range, nevertheless the ionosphere was considered fully opaque for extremely low frequency (ELF) EM emission. However recently, in spite of theoretical estimations, the SR harmonics and power line emission (PLE) 50/60 Hz were discovered during flights of low Earth orbiting satellites C/NOFS (Simões et al., 2011) and Chibis-M (Dudkin et al., 2015) at heights 400-800 km, i.e. over F2-layer. Last results are a great challenge to the theory of ELF EM emission propagation in the Earth's ionosphere as well as for study of long-term influence of constantly increasing electric energy consumption by human civilization in the Earth's environment. We present the analysis of the space and time distribution for observed PLE and SR harmonics, their connection with power terrestrial sources of ELF emission and possible relation between measured values and ionosphere conditions. Also some electromagnetic parameters have been estimated. Simões, F. A., R. F. Pfaff, and H. T. Freudenreich (2011), Satellite observations of Schumann resonances in the Earth's ionosphere, Geophys. Res. Lett., 38, L22101, doi:10.1029/2011GL049668. Dudkin, F., V. Korepanov, D. Dudkin, V. Pilipenko, V. Pronenko, and S. Klimov (2015), Electric fi eld of the power terrestrial sources observed by microsatellite Chibis-M in the Earth ' s ionosphere in frequency range 1 - 60 Hz, Geophys. Res. Lett., 42, doi:10.1002/2015GL064595.

High Speed Photographic Analysis Of Railgun Plasmas

NASA Astrophysics Data System (ADS)

Macintyre, I. B.

1985-02-01

Various experiments are underway at the Materials Research Laboratories, Australian Department of Defence, to develop a theory for the behaviour and propulsion action of plasmas in rail guns. Optical recording and imaging devices, with their low vulnerability to the effects of magnetic and electric fields present in the vicinity of electromagnetic launchers, have proven useful as diagnostic tools. This paper describes photoinstrumentation systems developed to provide visual qualitative assessment of the behaviour of plasma travelling along the bore of railgun launchers. In addition, a quantitative system is incorporated providing continuous data (on a microsecond time scale) of (a) Length of plasma during flight along the launcher bore. (b) Velocity of plasma. (c) Distribution of plasma with respect to time after creation. (d) Plasma intensity profile as it travels along the launcher bore. The evolution of the techniques used is discussed. Two systems were employed. The first utilized a modified high speed streak camera to record the light emitted from the plasma, through specially prepared fibre optic cables. The fibre faces external to the bore were then imaged onto moving film. The technique involved the insertion of fibres through the launcher body to enable the plasma to be viewed at discrete positions as it travelled along the launcher bore. Camera configuration, fibre optic preparation and experimental results are outlined. The second system utilized high speed streak and framing photography in conjunction with accurate sensitometric control procedures on the recording film. The two cameras recorded the plasma travelling along the bore of a specially designed transparent launcher. The streak camera, fitted with a precise slit size, recorded a streak image of the upper brightness range of the plasma as it travelled along the launcher's bore. The framing camera recorded an overall view of the launcher and the plasma path, to the maximum possible, governed by the film's ability to reproduce the plasma's brightness range. The instrumentation configuration, calibration, and film measurement using microdensitometer scanning techniques to evaluate inbore plasma behaviour, are also presented.

Engines for the Cosmos

NASA Technical Reports Server (NTRS)

Rodgers, Stephen L.; Reisz, Al; Wyckoff, James (Technical Monitor)

2002-01-01

Galactic forces spiral across the cosmos fueled by nuclear fission and fusion and atoms in plasmatic states with throes of constraints of gravitational forces and magnetic fields, In their wanderings these galaxies spew light, radiation, atomic and subatomic particles throughout the universe. Throughout the ages of man visions of journeying through the stars have been wondered. If humans and human devices from Earth are to go beyond the Moon and journey into deep space, it must be accomplished with like forces of the cosmos such as electrical fields, magnetic fields, ions, electrons and energies generated from the manipulation of subatomic and atomic particles. Forms of electromagnetic waves such as light, radio waves and lasers must control deep space engines. We won't get far on our Earth accustomed hydrocarbon fuels.

The potential of space exploration for education

NASA Technical Reports Server (NTRS)

Shair, Fredrick H.

1993-01-01

Space exploration and observations from space offer unique opportunities with respect to education. Recent technical advances have significantly increased the width and sensitivity of the electromagnetic spectrum window through which we are able to 'see' the universe. Observations from space have forced a realization that the earth is a beautiful, complex, and interconnected system. Space astronomy and the remote sensing of objects throughout our solar system have the potential of providing unique educational opportunities. Modern technologies have significantly reduced the cost of collecting, transmitting and processing data. Consequently, we are entering an age where it is possible to open up the process of discovery to almost everyone - and especially to young people throughout the world.

The Sun and Earth

NASA Technical Reports Server (NTRS)

Gopalswamy, Natchimuthuk

2012-01-01

Thus the Sun forms the basis for life on Earth via the black body radiation it emits. The Sun also emits mass in the form of the solar wind and the coronal mass ejections (CMEs). Mass emission also occurs in the form of solar energetic particles (SEPs), which happens during CMEs and solar flares. Both the mass and electromagnetic energy output of the Sun vary over a wide range of time scales, thus introducing disturbances on the space environment that extends from the Sun through the entire heliosphere including the magnetospheres and ionospheres of planets and moons of the solar system. Although our habitat is located in the neutral atmosphere of Earth, we are intimately connected to the non-neutral space environment starting from the ionosphere to the magnetosphere and to the vast interplanetary space. The variability of the solar mass emissions results in the interaction between the solar wind plasma and the magnetospheric plasma leading to huge disturbances in the geospace. The Sun ionizes our atmosphere and creates the ionosphere. The ionosphere can be severely disturbed by the transient energy input from solar flares and the solar wind during geomagnetic storms. The complex interplay between Earth's magnetic field and the solar magnetic field carried by the solar wind presents varying conditions that are both beneficial and hazardous to life on earth. This seminar presents some of the key aspects of this Sun-Earth connection that we have learned since the birth of space science as a scientific discipline some half a century ago.

HyperPASS, a New Aeroassist Tool

NASA Technical Reports Server (NTRS)

Gates, Kristin; McRonald, Angus; Nock, Kerry

2005-01-01

A new software tool designed to perform aeroassist studies has been developed by Global Aerospace Corporation (GAC). The Hypersonic Planetary Aeroassist Simulation System (HyperPASS) [1] enables users to perform guided aerocapture, guided ballute aerocapture, aerobraking, orbit decay, or unguided entry simulations at any of six target bodies (Venus, Earth, Mars, Jupiter, Titan, or Neptune). HyperPASS is currently being used for trade studies to investigate (1) aerocapture performance with alternate aeroshell types, varying flight path angle and entry velocity, different gload and heating limits, and angle of attack and angle of bank variations; (2) variable, attached ballute geometry; (3) railgun launched projectile trajectories, and (4) preliminary orbit decay evolution. After completing a simulation, there are numerous visualization options in which data can be plotted, saved, or exported to various formats. Several analysis examples will be described.

Study of interaction of ELF-ULF range (0.1-200 Hz) electromagnetic waves with the earth's crust and the ionosphere in the field of industrial power transmission lines (FENICS experiment)

NASA Astrophysics Data System (ADS)

Zhamaletdinov, A. A.; Shevtsov, A. N.; Velikhov, E. P.; Skorokhodov, A. A.; Kolesnikov, V. E.; Korotkova, T. G.; Ryazantsev, P. A.; Efimov, B. V.; Kolobov, V. V.; Barannik, M. B.; Prokopchuk, P. I.; Selivanov, V. N.; Kopytenko, Yu. A.; Kopytenko, E. A.; Ismagilov, V. S.; Petrishchev, M. S.; Sergushin, P. A.; Tereshchenko, P. E.; Samsonov, B. V.; Birulya, M. A.; Smirnov, M. Yu.; Korja, T.; Yampolski, Yu. M.; Koloskov, A. V.; Baru, N. A.; Poljakov, S. V.; Shchennikov, A. V.; Druzhin, G. I.; Jozwiak, W.; Reda, J.; Shchors, Yu. G.

2015-12-01

This article is devoted to describing the theory, technique, and first experimental results of a control source electromagnetic (CSEM) study of the Earth's crust and ionosphere with the use of two mutually orthogonal industrial transmission lines 109 and 120 km in length in the frame of FENICS (Fennoscandian Electrical Conductivity from Natural and Induction Control Source Soundings) experiment. The main part of the measurements is executed on the territory of the Fennoscandian shield at distances from the first hundreds kilometers up to 856 km from the source with the purpose of the deep electromagnetic sounding of the Earth's crust and upper mantle. According to the results of these studies clarifying the parameters of "normal" (standard) geoelectric section of the lithosphere to a depth of 60-70 km, the anisotropy parameters are evaluated and a geothermal and rheological interpretation in conjunction with the analysis of the seismic data is executed. Furthermore, to study the propagation of ELF-LLF waves (0.1-200 Hz) in an "Earth-Ionosphere" waveguide, the measurements are carried out apart from Fennoscandian shield at distances up to 5600 km from the source (in Ukraine, Spitsbergen, Poland, Kamchatka, and other areas). According to the results of these studies, the experimental estimates of the influence of the ionosphere and of the displacement currents on the propagation of ELF-ULF waves in the upper half-space at the different azimuths generation of the primary field are obtained.

Cross section parameterizations for cosmic ray nuclei. 1: Single nucleon removal

NASA Technical Reports Server (NTRS)

Norbury, John W.; Townsend, Lawrence W.

1992-01-01

Parameterizations of single nucleon removal from electromagnetic and strong interactions of cosmic rays with nuclei are presented. These parameterizations are based upon the most accurate theoretical calculations available to date. They should be very suitable for use in cosmic ray propagation through interstellar space, the Earth's atmosphere, lunar samples, meteorites, spacecraft walls and lunar and martian habitats.

The first Earth Resources Technology Satellite (ERTS-1)

NASA Technical Reports Server (NTRS)

Nordberg, W.

1973-01-01

The first Earth Resources Technology Satellite (ERTS-1) makes images of the earth's surface in four portions of the electromagnetic spectrum with sufficient spatial resolution and with a minimum of geometric distortions, so that these images may be applied experimentally to the study of geophysical processes relating to earth resources, to the exploration and conservation of these resources, and to the assessments of environmental stresses. During the first six months of operation, ERTS-1 has imaged 6.5 million square kilometers of the earth's surface every day, covering most major land masses and coastal zones as well as both polar regions of this planet. These images as well as the results of their analyses are available to all people throughout the world. Scientific investigators of all countries have been invited to participate in the utilization of ERTS-1 observations. Many of them have already demonstrated the great efficiency, economy, and reliability of making earth surveys from space.

Towards a better understanding of high-energy electron pitch-angle scattering by electromagnetic ion cyclotron waves

NASA Astrophysics Data System (ADS)

Vincena, S.; Gekelman, W.; Pribyl, P.; Tang, S., W.,; Papadopoulos, K.

2017-10-01

Shear Alfven waves are a fundamental mode in magnetized plasmas. Propagating near the ion cyclotron frequency, these waves are often termed electromagnetic ion cyclotron (EMIC) waves and can involve multiple ion species. Near the earth, for example, the wave may interact resonantly with oxygen ions at altitudes ranging from 1000 to 2000 km. The waves may either propagate from space towards the earth (possibly involving mode conversion), or be generated by RF transmitters on the ground. These preliminary experiments are motivated by theoretical predictions that such waves can pitch-angle scatter relativistic electrons trapped in the earth's dipole field. EMIC waves are launched in the Large Plasma Device at UCLA's Basic Plasma Science Facility in plasmas with single and multiple ion species into magnetic field gradients where ion cyclotron resonance is satisfied. We report here on the frequency and k-spectra in the critical layer and how they compare with theoretical predictions in computing an effective diffusion coefficient for high-energy electrons. Funding is provided by the NSF, DoE, and AFSOR.

The SRS railgun

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

Parker, J.V.

1989-01-01

A Segmented Rail Surface (SRS) structure is described that eliminates restrike arcs by progressively disconnecting segments of the rail surface after the plasma armature has passed. This technique has been demonstrated using the Los Alamos MIDI-2 railgun. Restrike was eliminated in a plasma armature acceleration experiment using metal-foil fuses as opening switches. A plasma velocity increase from 11 to 16 km/s was demonstrated using the SRS technique to eliminate the viscous drag losses associated with the restrike plasma. This technique appears to be a practical option for a laboratory launcher at present and for future multi-shot launchers if appropriate switchesmore » can be developed.« less

Computer simulations of electromagnetic cool ion beam instabilities. [in near earth space

NASA Technical Reports Server (NTRS)

Gary, S. P.; Madland, C. D.; Schriver, D.; Winske, D.

1986-01-01

Electromagnetic ion beam instabilities driven by cool ion beams at propagation parallel or antiparallel to a uniform magnetic field are studied using computer simulations. The elements of linear theory applicable to electromagnetic ion beam instabilities and the simulations derived from a one-dimensional hybrid computer code are described. The quasi-linear regime of the right-hand resonant ion beam instability, and the gyrophase bunching of the nonlinear regime of the right-hand resonant and nonresonant instabilities are examined. It is detected that in the quasi-linear regime the instability saturation is due to a reduction in the beam core relative drift speed and an increase in the perpendicular-to-parallel beam temperature; in the nonlinear regime the instabilities saturate when half the initial beam drift kinetic energy density is converted to fluctuating magnetic field energy density.

EXPOSE-E: an ESA astrobiology mission 1.5 years in space.

PubMed

Rabbow, Elke; Rettberg, Petra; Barczyk, Simon; Bohmeier, Maria; Parpart, André; Panitz, Corinna; Horneck, Gerda; von Heise-Rotenburg, Ralf; Hoppenbrouwers, Tom; Willnecker, Rainer; Baglioni, Pietro; Demets, René; Dettmann, Jan; Reitz, Guenther

2012-05-01

The multi-user facility EXPOSE-E was designed by the European Space Agency to enable astrobiology research in space (low-Earth orbit). On 7 February 2008, EXPOSE-E was carried to the International Space Station (ISS) on the European Technology Exposure Facility (EuTEF) platform in the cargo bay of Space Shuttle STS-122 Atlantis. The facility was installed at the starboard cone of the Columbus module by extravehicular activity, where it remained in space for 1.5 years. EXPOSE-E was returned to Earth with STS-128 Discovery on 12 September 2009 for subsequent sample analysis. EXPOSE-E provided accommodation in three exposure trays for a variety of astrobiological test samples that were exposed to selected space conditions: either to space vacuum, solar electromagnetic radiation at >110 nm and cosmic radiation (trays 1 and 3) or to simulated martian surface conditions (tray 2). Data on UV radiation, cosmic radiation, and temperature were measured every 10 s and downlinked by telemetry. A parallel mission ground reference (MGR) experiment was performed on ground with a parallel set of hardware and samples under simulated space conditions. EXPOSE-E performed a successful 1.5-year mission in space.

The high-performance electric field detector EFD for space-based measurements

NASA Astrophysics Data System (ADS)

Badoni, Davide

2016-04-01

We present the prototype of a new electric field detector (EFD) for space applications, that has been built and fully tested in laboratory in the framework of the LIMADOU collaboration between Italy and China aimed at developing the CSES (China Seismo-Electromagnetic Satellite) space mission (launch scheduled by the end of 2016). Investigations of the electromagnetic near-Earth space environment represent an important field of research as demonstrated by the satellite missions, already accomplished and/or planned to be launched in the near future, devoted to such issue (e.g. INJUN-5; POLAR, DEMETER, THEMIS, TARANIS, CSES, etc.). The payload of these satellites includes several instruments to measure electric fields in a broad frequency band along with magnetic field, plasma parameters and high energy particles fluxes. Even though these phenomena are mainly dominated by the solar activity, they are also conditioned by atmospheric and ionospheric processes, seismic activity, and human electromagnetic sources. The CSES mission will prosecute the exploratory study performed by the DEMETER satellite, by studying the electromagnetic, plasma and particle perturbations caused by seismicity in the ionosphere, magnetosphere and inner Van Allen belts. This task will be carried out through a detailed investigation of the anomalous electromagnetic field fluctuations, ionospheric plasma perturbations and instabilities accompanying earthquakes of moderate and strong magnitude, as observed by numerous satellite. As a secondary objective, the CSES satellite will also investigate the influence of the electromagnetic emissions of anthropogenic origin on the ionosphere and magnetosphere. The EFD detector consists of four probes designed to be installed on four booms deployed from the 3-axes stabilized satellite. The instrument has been conceived for space-borne measurements of electromagnetic phenomena such as magnetospheric waves, seimo-electromagnetic perturbations, anthropogenic electromagnetic emissions and more in general to investigate lithosphere-atmosphere-ionosphere EM coupling. The EFD can measure electric field in a wide band of frequencies extending from quasi-DC up to about 5 MHz. The resolution in the ULF band is better than 1μV/m with a dynamic range of 120 dB. This is a value 40 times better than that of any other recent instrument of similar quality. The sensitivity, in measuring d.o.p., in the other bands (ELF, VLF and HF) is better than 300 nV/√Hz, i.e. - by considering the boom lengths - the sensitivity in measuring electric field is of the order of 50 nV/(√Hz m). With these bandwidth and precision, the described electric field detector represents the most performing and updated device so far developed for electric field measurements in near-space applications. We present the description of the EFD instrument electronics and the results of the preliminary tests performed on the prototype in laboratory.

Kinds of Astronomy-5

NASA Technical Reports Server (NTRS)

Ennico, Kimberly; DeVincenzi, D. (Technical Monitor)

2001-01-01

Astronomers study light and basically, almost everything we know about the universe has been figured out through the study of light gathered by telescopes on the earth, in the earth's atmosphere, and in space. This light comes in many different colors, the sum of which comprises what is commonly I known as the electromagnetic (EM) spectrum. Unfortunately, the earth's atmosphere blocks almost all of wavelengths in the EM spectrum. Only the visible (400-700 mn) and radio (approx. 1-150 m) "windows" are accessible from the ground, and thus have the longest observational "history." These early restrictions on the observational astronomer also gave rise to classifying "kinds" of astronomy based on their respective EM portion, such as the term "radio astronomy."

NASA Office of Aeronautics and Space Technology Summer Workshop. Volume 5: Propulsion technology panel, part 1

NASA Technical Reports Server (NTRS)

1975-01-01

Payload experiments which could be carried out in near earth space using the shuttle orbiter, its payload bay, the Spacelab, and/or some free-flying device that might be used for long duration testing were identified. Specific areas examined in terms of user requirements include: chemical propulsion, nuclear propulsion (fission, fussion, radioisotopes), and collected energy (coherent energy and solar electromagnetic energy). Cost reduction objectives for advanced propulsion technology development were also developed.

Stochastic Growth of Ion Cyclotron And Mirror Waves In Earth's Magnetosheath

NASA Technical Reports Server (NTRS)

Cairns, Iver H.; Grubits, K. A.

2001-01-01

Electromagnetic ion cyclotron and mirror waves in Earth's magnetosheath are bursty, have widely variable fields, and are unexpectedly persistent, properties difficult to reconcile with uniform secular growth. Here it is shown for specific periods that stochastic growth theory (SGT) quantitatively accounts for the functional form of the wave statistics and qualitatively explains the wave properties. The wave statistics are inconsistent with uniform secular growth or self-organized criticality, but nonlinear processes sometimes play a role at high fields. The results show SGT's relevance near marginal stability and suggest that it is widely relevant to space and astrophysical plasmas.

Research in Space Physics at the University of Iowa. [spaceborne experiments and instruments

NASA Technical Reports Server (NTRS)

Vanallen, J. A.

1981-01-01

Currently active projects conducted to extend knowledge of the energetic particles and the electric, magnetic, and electromagnetic fields associated with Earth, other celestial bodies, and the interplanetary medium are summarized. These include investigations and/or instruments for Hawkeye 1; Pioneers 10 and 11; Voyagers 1 and 2; ISEE; IMP 8; Dynamics Explorer; Galileo; Spacelab and Orbital flight test missions; VLBI; and the International Solar Polar mission. Experiments and instruments proposed for the future international comet mission, the origin of plasmas in the Earth's environment mission, and the NASA active magnetospheric particle tracer experiment are mentioned.

Tests of the gravitational redshift effect in space-born and ground-based experiments

NASA Astrophysics Data System (ADS)

Vavilova, I. B.

2018-02-01

This paper provides a brief overview of experiments as concerns with the tests of the gravitational redshift (GRS) effect in ground-based and space-born experiments. In particular, we consider the GRS effects in the gravitational field of the Earth, the major planets of the Solar system, compact stars (white dwarfs and neutron stars) where this effect is confirmed with a higher accuracy. We discuss availabilities to confirm the GRS effect for galaxies and galaxy clusters in visible and X-ray ranges of the electromagnetic spectrum.

Development of High Energy Particle Detector for the Study of Space Storms onboard Next Generation Small Satellite-1

NASA Astrophysics Data System (ADS)

Sohn, J. D.; Min, K.; Lee, J.; Lee, D. Y.; Yi, Y.; Kang, K.; Shin, G. H.; Jo, G. B.; Lee, S. U.; Na, G.

2017-12-01

We reports the development of the High Energy Particle Detector (HEPD), one of the radiation detectors on board the Next Generation Small Satellite-1 to be launched into a low-Earth polar orbit in late 2017. The HEPD consists of three telescopes, each with a field of view of 33.4°, that are mounted on the satellite to have an angle of 0°, 45°, and 90° to the geomagnetic field during observations in the Earth's sub-auroral regions. The detection system of each telescope is composed of two silicon surface barrier detectors (SSDs), with the capability of measuring electrons from 300 keV to 2 MeV at 32 Hz that precipitate into the polar regions from the Earth's radiation belts when space storms occur. The successful operation of the HEPD in orbit will help us understand the interaction mechanisms between energetic electrons and plasma waves such as whistler and Electromagnetic Ion Cyclotron (EMIC) waves that are believed to be responsible for the energization and loss of high energy electrons in the Earth's radiation belts.

A Review of Low Frequency Electromagnetic Wave Phenomena Related to Tropospheric-Ionospheric Coupling Mechanisms

NASA Technical Reports Server (NTRS)

Simoes, Fernando; Pfaff, Robert; Berthelier, Jean-Jacques; Klenzing, Jeffrey

2012-01-01

Investigation of coupling mechanisms between the troposphere and the ionosphere requires a multidisciplinary approach involving several branches of atmospheric sciences, from meteorology, atmospheric chemistry, and fulminology to aeronomy, plasma physics, and space weather. In this work, we review low frequency electromagnetic wave propagation in the Earth-ionosphere cavity from a troposphere-ionosphere coupling perspective. We discuss electromagnetic wave generation, propagation, and resonance phenomena, considering atmospheric, ionospheric and magnetospheric sources, from lightning and transient luminous events at low altitude to Alfven waves and particle precipitation related to solar and magnetospheric processes. We review in situ ionospheric processes as well as surface and space weather phenomena that drive troposphere-ionosphere dynamics. Effects of aerosols, water vapor distribution, thermodynamic parameters, and cloud charge separation and electrification processes on atmospheric electricity and electromagnetic waves are reviewed. We also briefly revisit ionospheric irregularities such as spread-F and explosive spread-F, sporadic-E, traveling ionospheric disturbances, Trimpi effect, and hiss and plasma turbulence. Regarding the role of the lower boundary of the cavity, we review transient surface phenomena, including seismic activity, earthquakes, volcanic processes and dust electrification. The role of surface and atmospheric gravity waves in ionospheric dynamics is also briefly addressed. We summarize analytical and numerical tools and techniques to model low frequency electromagnetic wave propagation and solving inverse problems and summarize in a final section a few challenging subjects that are important for a better understanding of tropospheric-ionospheric coupling mechanisms.

STS-35 MS Hoffman and PS Durrance on OV-102's middeck for 'Space Classroom'

NASA Technical Reports Server (NTRS)

1990-01-01

STS-35 Mission Specialist (MS) Jeffrey A. Hoffman (mustache) and Payload Specialist (PS) Samuel T. Durrance conduct 'Space Classroom Assignment: The Stars' on the middeck of Columbia, Orbiter Vehicle (OV) 102. These crewmembers are giving students a lesson on the electromagnetic spectrum. Displayed behind them on the orbiter galley is a chart showing the range of light visible by each telescope that is operating in OV-102's payload bay (PLB) during the Astronomy Laboratory 1 (ASTRO-1) mission. Live television allowed the space experts to give real-time observations and commentaries to the Earth-based academic audiences.

Space Shuttle Projects

NASA Image and Video Library

1997-01-01

This is a view of the Russian Mir Space Station photographed by a crewmember of the fifth Shuttle/Mir docking mission, STS-81. The image shows: upper center - Progress supply vehicle, Kvant-1 module, and Core module; center left - Priroda module; center right - Spektr module; bottom left - Kvant-2 module; bottom center - Soyuz; and bottom right - Kristall module and Docking module. The Progress was an unmarned, automated version of the Soyuz crew transfer vehicle, designed to resupply the Mir. The Kvant-1 provided research in the physics of galaxies, quasars, and neutron stars, by measuring electromagnetic spectra and x-ray emissions. The Core module served as the heart of the space station and contained the primary living and working areas, life support, and power, as well as the main computer, communications, and control equipment. Priroda's main purpose was Earth remote sensing. The Spektr module provided Earth observation. It also supported research into biotechnology, life sciences, materials science, and space technologies. American astronauts used the Spektr as their living quarters. Kvant-2 was a scientific and airlock module, providing biological research, Earth observations, and EVA (extravehicular activity) capability. The Soyuz typically ferried three crewmembers to and from the Mir. A main purpose of the Kristall module was to develop biological and materials production technologies in the space environment. The Docking module made it possible for the Space Shuttle to dock easily with the Mir. The journey of the 15-year-old Russian Mir Space Station ended March 23, 2001, as the Mir re-entered the Earth's atmosphere and fell into the south Pacific Ocean.

A Science Strategy for Space Physics

NASA Technical Reports Server (NTRS)

1995-01-01

This report by the Committee on Solar and Space Physics and the Committee on Solar-Terrestrial Research recommends the major directions for scientific research in space physics for the coming decade. As a field of science, space physics has passed through the stage of simply looking to see what is out beyond Earth's atmosphere. It has become a 'hard' science, focusing on understanding the fundamental interactions between charged particles, electromagnetic fields, and gases in the natural laboratory consisting of the galaxy, the Sun, the heliosphere, and planetary magnetospheres, ionospheres, and upper atmospheres. The motivation for space physics research goes far beyond basic physics and intellectual curiosity, however, because long-term variations in the brightness of the Sun virtually affect the habitability of the Earth, while sudden rearrangements of magnetic fields above the solar surface can have profound effects on the delicate balance of the forces that shape our environment in space and on the human technology that is sensitive to that balance. The several subfields of space physics share the following objectives: to understand the fundamental laws or processes of nature as they apply to space plasmas and rarefied gases both on the microscale and in the larger complex systems that constitute the domain of space physics; to understand the links between changes in the Sun and the resulting effects at the Earth, with the eventual goal of predicting the significant effects on the terrestrial environment; and to continue the exploration and description of the plasmas and rarefied gases in the solar system.

Electromagnetic forward modelling for realistic Earth models using unstructured tetrahedral meshes and a meshfree approach

NASA Astrophysics Data System (ADS)

Farquharson, C.; Long, J.; Lu, X.; Lelievre, P. G.

2017-12-01

Real-life geology is complex, and so, even when allowing for the diffusive, low resolution nature of geophysical electromagnetic methods, we need Earth models that can accurately represent this complexity when modelling and inverting electromagnetic data. This is particularly the case for the scales, detail and conductivity contrasts involved in mineral and hydrocarbon exploration and development, but also for the larger scale of lithospheric studies. Unstructured tetrahedral meshes provide a flexible means of discretizing a general, arbitrary Earth model. This is important when wanting to integrate a geophysical Earth model with a geological Earth model parameterized in terms of surfaces. Finite-element and finite-volume methods can be derived for computing the electric and magnetic fields in a model parameterized using an unstructured tetrahedral mesh. A number of such variants have been proposed and have proven successful. However, the efficiency and accuracy of these methods can be affected by the "quality" of the tetrahedral discretization, that is, how many of the tetrahedral cells in the mesh are long, narrow and pointy. This is particularly the case if one wants to use an iterative technique to solve the resulting linear system of equations. One approach to deal with this issue is to develop sophisticated model and mesh building and manipulation capabilities in order to ensure that any mesh built from geological information is of sufficient quality for the electromagnetic modelling. Another approach is to investigate other methods of synthesizing the electromagnetic fields. One such example is a "meshfree" approach in which the electromagnetic fields are synthesized using a mesh that is distinct from the mesh used to parameterized the Earth model. There are then two meshes, one describing the Earth model and one used for the numerical mathematics of computing the fields. This means that there are no longer any quality requirements on the model mesh, which makes the process of building a geophysical Earth model from a geological model much simpler. In this presentation we will explore the issues that arise when working with realistic Earth models and when synthesizing geophysical electromagnetic data for them. We briefly consider meshfree methods as a possible means of alleviating some of these issues.

Limitations of Electromagnetic Ion Cyclotron Wave Observations in Low Earth Orbit

NASA Astrophysics Data System (ADS)

Hwang, Junga; Kim, Hyangpyo; Park, Jaeheung; Lee, Jaejin

2018-03-01

Pc1 pulsations are geomagnetic fluctuations in the frequency range of 0.2 to 5 Hz. There have been several observations of Pc1 pulsations in low earth orbit by MAGSAT, DE-2, Viking, Freja, CHAMP, and SWARM satellites. However, there has been a clear limitation in resolving the spatial and temporal variations of the pulsation by using a single-point observation by a single satellite. To overcome such limitations of previous observations, a new space mission was recently initiated, using the concept of multi-satellites, named the Small scale magNetospheric and Ionospheric Plasma Experiments (SNIPE). The SNIPE mission consists of four nanosatellites ( 10 kg), which will be launched into a polar orbit at an altitude of 600 km (TBD) in 2020. Four satellites will be deployed in orbit, and the distances between each satellite will be controlled from 10 to 1,000 km by a highend formation-flying algorithm. One of the possible science targets of the SNIPE mission is observing electromagnetic ion cyclotron (EMIC) waves. In this paper, we report on examples of observations, showing the limitations of previous EMIC observations in low earth orbit, and suggest possibilities to overcome those limitations through a new mission.

Origin of the Earth's Electromagnetic Field Based on the Pulsating Mantle Hypothesis (PMH)

NASA Astrophysics Data System (ADS)

Gholibeigian, Hassan

2017-11-01

In PMH, the Earth's Inner Core's Dislocation (ICD) and Outer Core's Bulge (OCB) phenomena are generated by unbalanced gravitational fields of the Sun and Moon on the Earth. Distance between the Earth's center and inner core's center varies permanently in magnitude and direction inside two hemispheres. Geometrical loci of the inner core's center has the shape of back and force spiral cone in each hemisphere. In other words, the inner core is rotating fast in the outer core inverse of the Earth's rotation a round per day. This mechanism speed up the processes inside the core and generates a Large Scale Forced Convection System (LSFCS) inverse of the Earth's rotation in the core. The LSFCS is the origin of the Earth's electromagnetic field. The LSFCS generates huge mass transfer and momentum of inertia inside the Earth too. The inner core's axis which is the Earth's electromagnetic axis doesn't cross the Earth's geophysical axis and rotates around it per day. The mechanism of this LSFCS has diurnal, monthly and yearly cycles. These cycles are sources of the Earth's electromagnetic field variability. Direction of the variable Earth's magnetic field lines from the South Pole (hemisphere) to the sky and 146 seconds/years apparent solar day length variations can be two observable factors for this mechanism. This dynamic system may occurred inside the other planets like the Sun and the Jupiter.

Meteoroids and Orbital Debris: Effects on Spacecraft

NASA Technical Reports Server (NTRS)

Belk, Cynthia A.; Robinson, Jennifer H.; Alexander, Margaret B.; Cooke, William J.; Pavelitz, Steven D.

1997-01-01

The natural space environment is characterized by many complex and subtle phenomena hostile to spacecraft. The effects of these phenomena impact spacecraft design, development, and operations. Space systems become increasingly susceptible to the space environment as use of composite materials and smaller, faster electronics increases. This trend makes an understanding of the natural space environment essential to accomplish overall mission objectives, especially in the current climate of better/cheaper/faster. Meteoroids are naturally occurring phenomena in the natural space environment. Orbital debris is manmade space litter accumulated in Earth orbit from the exploration of space. Descriptions are presented of orbital debris source, distribution, size, lifetime, and mitigation measures. This primer is one in a series of NASA Reference Publications currently being developed by the Electromagnetics and Aerospace Environments Branch, Systems Analysis and Integration Laboratory, Marshall Space Flight Center, National Aeronautics and Space Administration.

Theoretical performance of plasma driven railguns

NASA Astrophysics Data System (ADS)

Thio, Y. C.; McNab, I. R.; Condit, W. C.

1983-07-01

The overall efficiency of a railgun launch system is the product of efficiencies of its subsystems: prime mover, energy storage, pulse forming network, and accelerator. In this paper, the efficiency of the accelerator is examined in terms of the processes occurring in the accelerator. The principal loss mechanisms include Joule heating in the plasma, in the rails, kinetic energy of the driving plasma and magnetic energy remaining in the accelerator after projectile exit. The mass of the plasma and the atomic weight of the ionic species are important parameters in determining the energy loss in the plasma. Techniques are developed for selecting these parameters of minimize this loss.

Analytical investigation of the dynamics of tethered constellations in Earth orbit, phase 2

NASA Technical Reports Server (NTRS)

Lorenzini, Enrico C.; Gullahorn, Gordon E.; Cosmo, Mario L.; Estes, Robert D.; Grossi, Mario D.

1994-01-01

This final report covers nine years of research on future tether applications and on the actual flights of the Small Expendable Deployment System (SEDS). Topics covered include: (1) a description of numerical codes used to simulate the orbital and attitude dynamics of tethered systems during station keeping and deployment maneuvers; (2) a comparison of various tethered system simulators; (3) dynamics analysis, conceptual design, potential applications and propagation of disturbances and isolation from noise of a variable gravity/microgravity laboratory tethered to the Space Station; (4) stability of a tethered space centrifuge; (5) various proposed two-dimensional tethered structures for low Earth orbit for use as planar array antennas; (6) tethered high gain antennas; (7) numerical calculation of the electromagnetic wave field on the Earth's surface on an electrodynamically tethered satellite; (8) reentry of tethered capsules; (9) deployment dynamics of SEDS-1; (10) analysis of SEDS-1 flight data; and (11) dynamics and control of SEDS-2.

Energy Flow Exciting Field-Aligned Current at Substorm Expansion Onset

NASA Astrophysics Data System (ADS)

Ebihara, Y.; Tanaka, T.

2017-12-01

At substorm expansion onset, upward field-aligned currents (FACs) increase abruptly, and a large amount of electromagnetic energy starts to consume in the polar ionosphere. A question arises as to where the energy comes from. Based on the results obtained by the global magnetohydrodynamics simulation, we present energy flow and energy conversion associated with the upward FACs that manifest the onset. Our simulations show that the cusp/mantle region transmits electromagnetic energy to almost the entire region of the magnetosphere when the interplanetary magnetic field is southward. Integral curve of the Poynting flux shows a spiral moving toward the ionosphere, probably suggesting the pathway of electromagnetic energy from the cusp/mantle dynamo to the ionosphere. The near-Earth reconnection initiates three-dimensional redistribution of the magnetosphere. Flow shear in the near-Earth region results in the generation of the near-Earth dynamo and the onset FACs. The onset FACs are responsible to transport the electromagnetic energy toward the Earth. In the near-Earth region, the electromagnetic energy coming from the cusp/mantle dynamo is converted to the kinetic energy (known as bursty bulk flow) and the thermal energy (associated with high-pressure region in the inner magnetosphere). Then, they are converted to the electromagnetic energy associated with the onset FACs. A part of electromagnetic energy is stored in the lobe region during the growth phase. The release of the stored energy, together with the continuously supplied energy from the cusp/mantle dynamo, contributes to the energy supply to the ionosphere during the expansion phase.

Near Space Tracking of the EM Phenomena Associated with the Main Earthquakes

NASA Technical Reports Server (NTRS)

Ouzounov, Dimitar; Taylor, Patrick; Bryant, Nevin; Pulinets, Sergey; Liu, Jann-Yenq; Yang, Kwang-Su

2004-01-01

Searching for electromagnetic (EM) phenomena originating in the Earth's crust prior to major earthquakes (M>5) are the object of this exploratory study. We present the idea of a possible relationship between: (1) electro-chemical and thermodynamic processes in the Earth's crust and (2) ionic enhancement of the atmosphere/ionosphere with tectonic stress and earthquake activity. The major source of these signals are proposed to originate from electromagnetic phenomenon which are responsible for these observed pre-seismic processes, such as, enhanced IR emission, also born as thermal anomalies, generation of long wave radiation, light emission caused by ground-to-air electric discharges, Total Electron Content (TEC) ionospheric anomalies and ionospheric plasma variations. The source of these data will include: (i) ionospheric plasma perturbations data from the recently launched DEMETER mission and currently available TEC/GPS network data; (ii) geomagnetic data from ORSTED and CHAMP; (iii) Thermal infra-red (TIR) transients mapped by the polar orbiting (NOAA/AVHRR, MODIS) and (iv) geosynchronous weather satellites measurements of GOES, METEOSAT. This approach requires continues observations and data collecting, in addition to both ground and space based monitoring over selected regions in order to investigate the various techniques for recording possible anomalies. During the space campaign emphasis will be on IR emission, obtained from TIR (thermal infrared) satellites, that records land/sea surface temperature anomalies and changes in the plasma and total electron content (TEC) of the ionosphere that occur over areas of potential earthquake activity.

Rapid Charged Geosynchronous Debris Perturbation Modeling of Electrodynamic Disturbances

NASA Astrophysics Data System (ADS)

Hughes, Joseph; Schaub, Hanspeter

2018-06-01

Charged space objects experience small perturbative torques and forces from their interaction with Earth's magnetic field. These small perturbations can change the orbits of lightweight, uncontrolled debris objects dramatically even over short periods. This paper investigates the effects of the isolated Lorentz force, the effects of including or neglecting this and other electromagnetic perturbations in a full propagation, and then analyzes for which objects electromagnetic effects have the most impact. It is found that electromagnetic forces have a negligible impact on their own. However, if the center of charge is not collocated with the center of mass, electromagnetic torques are produced which do impact the attitude, and thus the position by affecting the direction and magnitude of the solar radiation pressure force. The objects for which electrostatic torques have the most influence are charged above the kilovolt level, have a difference between their center of mass and center of charge, have highly attitude-dependent cross-sectional area, and are not spinning stably about an axis of maximum inertia. Fully coupled numerical simulation illustrate the impact of electromagnetic disturbances through the solar radiation pressure coupling.

Rapid Charged Geosynchronous Debris Perturbation Modeling of Electrodynamic Disturbances

NASA Astrophysics Data System (ADS)

Hughes, Joseph; Schaub, Hanspeter

2018-04-01

Charged space objects experience small perturbative torques and forces from their interaction with Earth's magnetic field. These small perturbations can change the orbits of lightweight, uncontrolled debris objects dramatically even over short periods. This paper investigates the effects of the isolated Lorentz force, the effects of including or neglecting this and other electromagnetic perturbations in a full propagation, and then analyzes for which objects electromagnetic effects have the most impact. It is found that electromagnetic forces have a negligible impact on their own. However, if the center of charge is not collocated with the center of mass, electromagnetic torques are produced which do impact the attitude, and thus the position by affecting the direction and magnitude of the solar radiation pressure force. The objects for which electrostatic torques have the most influence are charged above the kilovolt level, have a difference between their center of mass and center of charge, have highly attitude-dependent cross-sectional area, and are not spinning stably about an axis of maximum inertia. Fully coupled numerical simulation illustrate the impact of electromagnetic disturbances through the solar radiation pressure coupling.

Numerical simulation of magnetic field for compact electromagnet consisting of REBCO coils and iron yoke

NASA Astrophysics Data System (ADS)

You, Shuangrong; Chi, Changxin; Guo, Yanqun; Bai, Chuanyi; Liu, Zhiyong; Lu, Yuming; Cai, Chuanbing

2018-07-01

This paper presents the numerical simulation of a high-temperature superconductor electromagnet consisting of REBCO (RE-Ba2Cu3O7‑x, RE: rare earth) superconducting tapes and a ferromagnetic iron yoke. The REBCO coils with multi-width design are operating at 77 K, with the iron yoke at room temperature, providing a magnetic space with a 32 mm gap between two poles. The finite element method is applied to compute the 3D model of the studied magnet. Simulated results show that the magnet generates a 1.5 T magnetic field at an operating current of 38.7 A, and the spatial inhomogeneity of the field is 0.8% in a Φ–20 mm diameter sphere volume. Compared with the conventional iron electromagnet, the present compact design is more suitable for practical application.

An analytic solution for numerical modeling validation in electromagnetics: the resistive sphere

NASA Astrophysics Data System (ADS)

Swidinsky, Andrei; Liu, Lifei

2017-11-01

We derive the electromagnetic response of a resistive sphere to an electric dipole source buried in a conductive whole space. The solution consists of an infinite series of spherical Bessel functions and associated Legendre polynomials, and follows the well-studied problem of a conductive sphere buried in a resistive whole space in the presence of a magnetic dipole. Our result is particularly useful for controlled-source electromagnetic problems using a grounded electric dipole transmitter and can be used to check numerical methods of calculating the response of resistive targets (such as finite difference, finite volume, finite element and integral equation). While we elect to focus on the resistive sphere in our examples, the expressions in this paper are completely general and allow for arbitrary source frequency, sphere radius, transmitter position, receiver position and sphere/host conductivity contrast so that conductive target responses can also be checked. Commonly used mesh validation techniques consist of comparisons against other numerical codes, but such solutions may not always be reliable or readily available. Alternatively, the response of simple 1-D models can be tested against well-known whole space, half-space and layered earth solutions, but such an approach is inadequate for validating models with curved surfaces. We demonstrate that our theoretical results can be used as a complementary validation tool by comparing analytic electric fields to those calculated through a finite-element analysis; the software implementation of this infinite series solution is made available for direct and immediate application.

An electromagnetic method for removing the communication blackout with a space vehicle upon re-entry into the atmosphere

NASA Astrophysics Data System (ADS)

Cheng, Jianjun; Jin, Ke; Kou, Yong; Hu, Ruifeng; Zheng, Xiaojing

2017-03-01

When a hypersonic vehicle travels in the Earth and Mars atmosphere, the surface of the vehicle is surrounded by a plasma layer, which is an envelope of ionized air, created from the compression and heat of the atmosphere by the shock wave. The vehicles will lose contact with ground stations known as the reentry communication blackout. Based on the magnetohydrodynamic framework and electromagnetic wave propagation theory, an analytical model is proposed to describe the effect of the effectiveness of electromagnetic mitigation scheme on removing the reentry communication blackout. C and Global Positioning System (GPS) bands, two commonly used radio bands for communication, are taken as the cases to discuss the effectiveness of the electromagnetic field mitigation scheme. The results show that the electron density near the antenna of vehicles can be reduced by the electromagnetic field, and the required external magnetic field strength is far below the one in the magnetic window method. The directions of the external electric field and magnetic field have a significant impact on the effectiveness of the mitigation scheme. Furthermore, the effect of electron collisions on the required applied electromagnetic field is discussed, and the result indicates that electron collisions are a key factor to analyze the electromagnetic mitigation scheme. Finally, the feasible regions of the applied electromagnetic field for eliminating blackout are given. These investigations could have a significant benefit on the design and optimization of electromagnetic mitigation scheme for the blackout problem.

The SRS (Segmented Rail Surface) railgun: A new approach to restrike control. [Segmented rail surface

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

Parker J.V.

1988-01-01

A Segmented Rail Surface (SRS) structure is described that eliminates restrike arcs by progressively disconnecting segments of the rail surface after the plasma armature has passed. This technique has been demonstrated using the Los Alamos MIDI-2 railgun. Restrike was eliminated in a plasma armature acceleration experiment using metal-foil fuses as opening switches. A plasma velocity increase from 11 to 16 km/s was demonstrated using the SRS technique to eliminate the viscous drag losses associated with the restrike plasma. This technique appears to be a practical option for a laboratory launcher at present and for future multi-shot launchers if appropriate switchesmore » can be developed. 5 refs., 8 figs.« less

Rail accelerator research at Lewis Research Center

NASA Technical Reports Server (NTRS)

Kerslake, W. R.; Cybyk, B. Z.

1982-01-01

A rail accelerator was chosen for study as an electromagnetic space propulsion device because of its simplicity and existing technology base. The results of a mission feasibility study using a large rail accelerator for direct launch of ton-size payloads from the Earth's surface to space, and the results of initial tests with a small, laboratory rail accelerator are presented. The laboratory rail accelerator has a bore of 3 by 3 mm and has accelerated 60 mg projectiles to velocities of 300 to 1000 m/s. Rail materials of Cu, W, and Mo were tested for efficiency and erosion rate.

German activities in optical space instrumentation

NASA Astrophysics Data System (ADS)

Hartmann, G.

2018-04-01

In the years of space exploration since the mid-sixties, a wide experience in optical space instrumentation has developed in Germany. This experience ranges from large telescopes in the 1 m and larger category with the accompanying focal plane detectors and spectrometers for all regimes of the electromagnetic spectrum (infrared, visible, ultraviolet, x-rays), to miniature cameras for cometary and planetary explorations. The technologies originally developed for space science. are now also utilized in the fields of earth observation and even optical telecommunication. The presentation will cover all these areas, with examples for specific technological or scientific highlights. Special emphasis will be given to the current state-of-the-art instrumentation technologies in scientific institutions and industry, and to the future perspective in approved and planned projects.

Space Earthquake Perturbation Simulation (SEPS) an application based on Geant4 tools to model and simulate the interaction between the Earthquake and the particle trapped on the Van Allen belt

NASA Astrophysics Data System (ADS)

Ambroglini, Filippo; Jerome Burger, William; Battiston, Roberto; Vitale, Vincenzo; Zhang, Yu

2014-05-01

During last decades, few space experiments revealed anomalous bursts of charged particles, mainly electrons with energy larger than few MeV. A possible source of these bursts are the low-frequency seismo-electromagnetic emissions, which can cause the precipitation of the electrons from the lower boundary of their inner belt. Studies of these bursts reported also a short-term pre-seismic excess. Starting from simulation tools traditionally used on high energy physics we developed a dedicated application SEPS (Space Perturbation Earthquake Simulation), based on the Geant4 tool and PLANETOCOSMICS program, able to model and simulate the electromagnetic interaction between the earthquake and the particles trapped in the inner Van Allen belt. With SEPS one can study the transport of particles trapped in the Van Allen belts through the Earth's magnetic field also taking into account possible interactions with the Earth's atmosphere. SEPS provides the possibility of: testing different models of interaction between electromagnetic waves and trapped particles, defining the mechanism of interaction as also shaping the area in which this takes place,assessing the effects of perturbations in the magnetic field on the particles path, performing back-tracking analysis and also modelling the interaction with electric fields. SEPS is in advanced development stage, so that it could be already exploited to test in details the results of correlation analysis between particle bursts and earthquakes based on NOAA and SAMPEX data. The test was performed both with a full simulation analysis, (tracing from the position of the earthquake and going to see if there were paths compatible with the burst revealed) and with a back-tracking analysis (tracing from the burst detection point and checking the compatibility with the position of associated earthquake).

Engaging Scientists in NASA Education and Public Outreach: Tools for Scientist Engagement

NASA Astrophysics Data System (ADS)

Buxner, Sanlyn; Meinke, B. K.; Hsu, B.; Shupla, C.; Grier, J. A.; E/PO Community, SMD

2014-01-01

The NASA Science Education and Public Outreach Forums support the NASA Science Mission Directorate (SMD) and its education and public outreach (E/PO) community through a coordinated effort to enhance the coherence and efficiency of SMD-funded E/PO programs. The Forums foster collaboration between scientists with content expertise and educators with pedagogy expertise. We present tools and resources to support astronomers’ engagement in E/PO efforts. Among the tools designed specifically for scientists are a series of one-page E/PO-engagement Tips and Tricks guides, a sampler of electromagnetic-spectrum-related activities, and NASA SMD Scientist Speaker’s Bureau (http://www.lpi.usra.edu/education/speaker). Scientists can also locate resources for interacting with diverse audiences through a number of online clearinghouses, including: NASA Wavelength, a digital collection of peer-reviewed Earth and space science resources for educators of all levels (http://nasawavelength.org), and EarthSpace (http://www.lpi.usra.edu/earthspace), a community website where faculty can find and share teaching resources for the undergraduate Earth and space sciences classroom. Learn more about the opportunities to become involved in E/PO and to share your science with students, educators, and the general public at http://smdepo.org.

Space Shuttle Projects

NASA Image and Video Library

1995-11-01

This is a view of the Russian Mir Space Station photographed by a crewmember of the second Shuttle/Mir docking mission, STS-74. The image shows: top - Progress supply vehicle, Kvant-1 module, and the Core module; middle left - Spektr module; middle center - Kristall module and Docking module; middle right - Kvant-2 module; and bottom - Soyuz. The Progress was an unmarned, automated version of the Soyuz crew transfer vehicle, designed to resupply the Mir. The Kvant-1 provided research in the physics of galaxies, quasars, and neutron stars by measuring electromagnetic spectra and x-ray emissions. The Core module served as the heart of the space station and contained the primary living and working areas, life support, and power, as well as the main computer, communications, and control equipment. The Spektr module provided Earth observation. It also supported research into biotechnology, life sciences, materials science, and space technologies. American astronauts used the Spektr as their living quarters. A main purpose of the Kristall module was to develop biological and materials production technologies in the space environment. The Docking module made it possible for the Space Shuttle to dock easily with the Mir. Kvant-2 was a scientific and airlock module, providing biological research, Earth observations, and EVA (extravehicular activity) capability. The Soyuz typically ferried three crewmembers to and from the Mir. The journey of the 15-year-old Russian Mir Space Station ended March 23, 2001, as the Mir re-entered the Earth's atmosphere and fell into the south Pacific Ocean.

The concept of a Space-Space interferometer for observations in mm and sub-mm wavebands

NASA Astrophysics Data System (ADS)

Andreyanov, V. V.

2007-12-01

At present, space radio astronomers and engineers study the prospects of design of the second-generation ground-space interferometers for astrophysical research with the microsecond angular resolution of sources. The implemented Japanese VSOP project (1998 2003) and the Russian Radioastron project (under preparation for space flight) are related to the first generation. In this paper, the ideology and configuration of the Space-Space interferometer are considered. It would allow one to obtain principally new capabilities: to exclude the Earth’s atmosphere influence, to realize a quasi-phase-stable interferometer, and to remove the problems of electromagnetic compatibility with other services. Moreover, a capability will appear to carry out preliminary correlation processing onboard the spacecraft due to achievement of small residual uncertainties in signal delay and frequency and, owing to this, to realize onboard data compression in order to transmit data to the Earth by usual space communication channel.

KSC-01pp1244

NASA Image and Video Library

2001-07-02

KENNEDY SPACE CENTER, Fla. -- At Astrotech, Titusville, Fla., workers look at the fairing being installed around the newest Geostationary Operational Environmental Satellite-M (GOES-M). The satellite is the last in the current series of advanced geostationary weather satellites in service. GOES-M has a new instrument not on earlier spacecraft, a Solar X-ray Imager that can be used in forecasting space weather, the effects of solar storms that create electromagnetic disturbances on earth that affect other satellites, communications and power grids. GOES is scheduled to launch from Launch Complex 36-A, Cape Canaveral Air Force Station, on an Atlas II rocket July 15

KSC-01pp1245

NASA Image and Video Library

2001-07-02

KENNEDY SPACE CENTER, Fla. -- At Astrotech, Titusville, Fla., both halves of the fairing are being installed around the newest Geostationary Operational Environmental Satellite-M (GOES-M). The satellite is the last in the current series of advanced geostationary weather satellites in service. GOES-M has a new instrument not on earlier spacecraft, a Solar X-ray Imager that can be used in forecasting space weather, the effects of solar storms that create electromagnetic disturbances on earth that affect other satellites, communications and power grids. GOES is scheduled to launch from Launch Complex 36-A, Cape Canaveral Air Force Station, on an Atlas II rocket July 15

Exploring the Earth's Radiation Belts

NASA Astrophysics Data System (ADS)

Daglis, I. A.; Anastasiadis, A.; Chatzichristou, E. T.; Ropokis, G.; Giannakis, O.

2012-09-01

We present the outreach efforts of the MAARBLE (Monitoring, Analyzing and Assessing Radiation Belt Loss and Energization) project, intended to provide the general public with simplified information concerning the scientific objectives of the project, its focus and its expected outcomes. MAARBLE involves monitoring of the geospace environment through space and ground-based observations, in order to understand various aspects of the radiation belts (torus-shaped regions encircling the Earth, in which high-energy charged particles are trapped by the geomagnetic field), which have direct impact on human endeavors in space (spacecraft and astronauts exposure). The public outreach website of MAARBLE, besides regular updates with relevant news, also employs a variety of multimedia (image and video galleries) and impressive sounds of space (characteristic sounds such as whistlers or tweeks) related to very low and ultra low frequency (VLF/ULF) electromagnetic waves. It also provides links to some of the most interesting relevant educational activities, including those at partner institutions such as the Institute of Geophysics and Planetary Physics at UCLA, the University of Alberta, the Swedish Institute of Space Physics and the Institute of Atmospheric Physics of the Academy of Sciences of the Czech Republic.

Composite Material Aircraft Electromagnetic Properties and Design Guidelines

DTIC Science & Technology

1981-01-01

Diode Characteristics for IN914 Diode at 220 MHz 7-6 7.5 Characteristics of a 2N2369A Transitor With and Without RF Interference on the Collector Lead...Analylsi Miser Reiponse Model Adjacent Channel Interference Summary 7. STATISTICAL AND NUMERICAL I. PROPAGATION MODELS ANALYSIS MASTER PROPAGATION SYSTEM...Propagation System lIPS) Simsulationst Smorothe Curve Smooth Earth (SCSIS) Oemtralltzd File Statistics Analyzer (Q63) flislance Free Space Spherical Raflectiot

Electromagnetic deep-probing (100-1000 kms) of the Earth's interior from artificial satellites: Constraints on the regional emplacement of crustal resources

NASA Technical Reports Server (NTRS)

Hermance, J. F.

1983-01-01

The reconnaissance phase of using satellite observtions to studying electromagnetic induction in the solid earth is summarized. Several points are made: (1) satellite data apparently suffer far less from the effects of near surface lateral heterogeneities in the earth than do ground-based data; (2) zonal ionospheric currents during the recovery phase of major magnetic storms appear to be minimal, at least in the dawn and dusk sectors wher MAGSAT was flown; hence the internal contributions that satellites observe during these times is in fact due primarily to induction in the Earth with little or no contribution from ionospheric currents; and (3) the interpretation of satellite data in terms of primitive electromagnetic response functions, while grossly over-simplified, results in a surprisingly well-resolved radius for an equivalent super-conductor representing the conductivity region of the Earth's interior (5,370 + or - 120 km).

North-south asymmetries in cold ion outflow and lobe density

NASA Astrophysics Data System (ADS)

Haaland, Stein; Laundal, Karl; Maes, Lukas; Baddeley, Lisa; Lybekk, Bjørn

2016-04-01

A significant fraction of the plasma in the terrestrial magnetosphere is supplied by the high-latitude ionosphere. The filling process starts with ionization of atoms and gas molecules in the thermosphere, and is often accompanied by upflow due to thermal and electromagnetic forces. Some of this material can reach escape velocities and be further accelerated and eventually evacuated into space. Ions are governed by electromagnetic forces and their transport path from the ionosphere to the magnetosphere go through the magnetotail lobes. The transport is largely dictated by magnetospheric convection. External influences, such as daily and seasonal variations in the Earth's tilt angle, but also non-dipolar terms in the Earth's internal magnetic field introduce north-south asymmetries in the magnetic field and thus north-south asymmetries in the ion outflow and lobe filling. In this presentation, we show observational results of this asymmetry. The results are based on more than a full solar cycle of cold ion measurements from the Cluster constellation of spacecraft, and allows us to quantify the outflow, identify sources of asymmetry and estimate transport paths.

Global Electromagnetic Imaging of Lithosphere and Upper Mantle from Space and Ground. Recent Results and Challenges

NASA Astrophysics Data System (ADS)

Kuvshinov, A. V.

2016-12-01

Electrical conductivity is one of the characteristic physical parameters of materials making up Earth's interior which is sensitive to variations of temperature, chemical composition, water content, and partial melt. As a consequence, estimating lithosphere and upper mantle (LUM) electrical conductivity structure is a potentially strong tool for mapping their chemistry, mineralogy and physical structure thus presenting a complementary method to seismic studies that focus on LUM elastic properties. Global electromagnetic (EM) studies, which provide information on LUM electrical conductivity, have attracted increasing interest during the last decade, mainly for three reasons. A primary reason is the recent growth in the amount of EM data available, especially from low-Earth orbiting magnetic satellite missions (Oersted, CHAMP, SAC-C, and Swarm). A second reason is the great interest in the characterization of the three-dimensional properties of Earth's interior on a global scale. Finally, the interest has also resulted from the significant methodological progress made during the last years in EM data analysis, forward modelling and inversion. In this talk I will summarize advances and challenges in EM data interpretation, and present recent global and regional models of LUM conductivity derived from satellite and ground-based data. I will also discuss possible topics for future research.

Future superconductivity applications in space - A review

NASA Astrophysics Data System (ADS)

Krishen, Kumar; Ignatiev, Alex

High temperature superconductor (HISC) materials and devices can provide immediate applications for many space missions. The in-space thermal environment provides an opportunity to develop, test, and apply this technology to enhance performance and reliability for many applications of crucial importance to NASA. Specifically, the technology development areas include: (1) high current power transmission, (2) microwave components, devices, and antennas, (3) microwave, optical, and infrared sensors, (4) signal processors, (5) submillimeter wave components and systems, (6) ultra stable space clocks, (7) electromagnetic launch systems, and (8) accelerometers and position sensors for flight operations. HTSC is expected to impact NASA's Lunar Bases, Mars exploration, Mission to Earth, and Planetary exploration programs providing enabling and cost-effect technology. A review of the space applications of the HTSC technology is presented. Problem areas in technology development needing special attention are identified.

Simulation of space radiation effects on polyimide film materials for high temperature applications

NASA Technical Reports Server (NTRS)

Fogdall, L. B.; Cannaday, S. S.

1977-01-01

Space environment effects on candidate materials for the solar sail film are determined. Polymers, including metallized polyimides that might be suitable solar radiation receivers, were exposed to combined proton and solar electromagnetic radiation. Each test sample was weighted, to simulate the tension on the polymer when it is stretched into near-planar shape while receiving solar radiation. Exposure rates up to 16 times that expected in Earth orbit were employed, to simulate near-sun solar sailing conditions. Sample appearance, elongation, and shrinkage were monitored, noted, and documented in situ. Thermosetting polyimides showed less degradation or visual change in appearance than thermoplastics.

Assessment of environmental effects on Space Station Freedom Electrical Power System

NASA Technical Reports Server (NTRS)

Lu, Cheng-Yi; Nahra, Henry K.

1991-01-01

Analyses of EPS (electrical power system) interactions with the LEO (low earth orbit) environment are described. The results of these analyses will support EPS design so as to be compatible with the natural and induced environments and to meet power, lifetime, and performance requirements. The environmental impacts to the Space Station Freedom EPS include aerodynamic drag, atomic oxygen erosion, ultraviolet degradation, VXB effect, ionizing radiation dose and single event effects, electromagnetic interference, electrostatic discharge, plasma interactions (ion sputtering, arcing, and leakage current), meteoroid and orbital debris threats, thermal cycling effects, induced current and voltage potential differences in the SSF due to induced electric field, and contamination degradation.

Experimental study of global electromagnetic resonances of the Earth-ionosphere cavity in high latitudes (Novaya Zemlya Island and settlement Tiksi)

NASA Astrophysics Data System (ADS)

Auyrov, D. B.; Khaptanov, V. B.; Bashkuev, Yu. B.; Buyanova, D. G.

2017-11-01

The results of measurements of the horizontal electric field Eh components of the natural electromagnetic field of the Earth (Schumann resonances, SR) in the extreme low frequency (ELF) radio wave bands on Novaya Zemlya Island and settlement Tiksi are considered. In the electromagnetic clean arctic region on August 2016 (the Bay of Blagopoluchiya (75°41'59″ N; 63° 42' 36″ E)) the global electromagnetic resonances (SR) of the Earth-ionosphere cavity up to the 7th and 8th resonant peaks in spectra are identified. Calculated and experimental values of the peak frequencies fn and Qnfactors of the cavity "Earth-ionosphere" are presented. On the spectra of records received on July, 2015 also in high latitudes near settlement Tiksi (71°35'3″ N; 128°46'4″ E) we work with the same measuring equipment and observed the 4th and 5th SR resonances. Diurnal variations of basic parameters of Schumann resonances are investigated.

The Quest for Contact: NASA's Search for Extraterrestrial Intelligence

NASA Technical Reports Server (NTRS)

1992-01-01

This video details the history and current efforts of NASA's Search for Extraterrestrial Intelligence program. The video explains the use of radiotelescopes to monitor electromagnetic frequencies reaching the Earth, and the analysis of this data for patterns or signals that have no natural origin. The video presents an overview of Frank Drake's 1960 'Ozma' experiment, the current META experiment, and planned efforts incorporating an international Deep Space Network of radiotelescopes that will be trained on over 800 stars.

Seismic Correlation and Coupling from Underground, Surface, to the Ionosphere

NASA Astrophysics Data System (ADS)

Wang, J. S.; Waysand, G.

2009-12-01

Electromagnetic activity correlated to seismicity is displayed in a variety of ways. Earthquake precursors and aftershocks associated with local fault slips have been detected regionally by visual observations and radar reflections, and globally by satellite measurements of electromagnetic profiles. Magnetic excitations have recently been measured underground that associated with major earthquakes (e.g., the 2008 Sichuan and the 2006 Pingtung earthquakes). In all cases, the frequencies are extremely low; hence, the corresponding wavelengths are extremely large. In other term, wherever an earthquake occurs on Earth, any electromagnetic measurement of it is always near-field from the signal source. Thus, signal-to-noise ratio is the only limiting factor. The increasing abundance of observations, and the variety of instruments enabling these observations, requires investigators to look beyond borders of their individual discipline and adopt a global approach to the problem. To elucidate the dynamic generation and propagation of seismic-induced electromagnetic signals, it is important to assess from small to large scales the variability of (1) the seismic-electromagnetic coupling at localized zones and block boundaries, (2) the potential signal paths through the earth geomagnetic fields, and (3) the ionosphere and atmospheric measurements and observations. The pre-earthquake signals as potential precursors have generated great interests for decades, especially with the deployments of satellites for geophysical measurements. The emerging understanding is that stress buildups and releases induce electromagnetic emissions which are likely associated with charged particle movements, propagations mainly along waveguides through the earth magnetic field to the atmosphere and ionosphere. The globally distributed perturbations and profiles above ground are systematically mapped. The signals could also be transmitted nearly vertically from epicenters to the ground and beyond, especially for post-earthquake periods with displacements associated with seismic wave arrivals at the ground surfaces. We assess the correlation and coupling among signals measured at depths, on the surface, and in the sky. While the main focus is on electromagnetic signals associated with earthquakes, there are many relevant measurements and analyses among seismic, rock mechanical, hydrochemical, electromagnetic, atmospheric, ionospheric and other processes and phenomena. The correlation of different signals in space and time can elucidate the different coupling and channeling of signals. The demonstrated low noise advantage of underground seismic-magnetic detections of global signals at the Laboratoire Souterrain Bas Bruit de Rustrel-Pays d'Apt should set the example for the establishment of equivalent stations worldwide in other underground research laboratories. We emphasize the adoption of international and inter-disciplinary approaches that can contribute to better understanding of mechanisms among different earthquake and tectonic forces, and lead to improved assessment of earthquake and related natural hazards.

The windows of SETI - Frequency and time in the search for extraterrestrial intelligence

NASA Technical Reports Server (NTRS)

Oliver, Bernard M.

1987-01-01

Since interstellar travel is not economically possible on the time scale of a human lifetime, communication with extraterrestrials can be achieved only by sending some form of energy or matter across space; photons (electromagnetic waves) are best. Of particular interest to SETI is the region from about 1,000-60,000 MHz known as the free-space microwave window. During the course of NASA's Cyclops program, it was pointed out that the hydrogen and hydroxyl lines bounded a band in which there were no other known lines. The threatened loss of the microwave window to earth-based services is discussed.

Remote sensing of earth terrain

NASA Technical Reports Server (NTRS)

Kong, Jin AU; Yueh, Herng-Aung; Shin, Robert T.

1991-01-01

Abstracts from 46 refereed journal and conference papers are presented for research on remote sensing of earth terrain. The topics covered related to remote sensing include the following: mathematical models, vegetation cover, sea ice, finite difference theory, electromagnetic waves, polarimetry, neural networks, random media, synthetic aperture radar, electromagnetic bias, and others.

Smart reconfigurable parabolic space antenna for variable electromagnetic patterns

NASA Astrophysics Data System (ADS)

Kalra, Sahil; Datta, Rituparna; Munjal, B. S.; Bhattacharya, Bishakh

2018-02-01

An application of reconfigurable parabolic space antenna for satellite is discussed in this paper. The present study focuses on shape morphing of flexible parabolic antenna actuated with Shape Memory Alloy (SMA) wires. The antenna is able to transmit the signals to the desired footprint on earth with a desired gain value. SMA wire based actuation with a locking device is developed for a precise control of Antenna shape. The locking device is efficient to hold the structure in deformed configuration during power cutoff from the system. The maximum controllable deflection at any point using such actuation system is about 25mm with a precision of ±100 m. In order to control the shape of the antenna in a closed feedback loop, a Proportional, Integral and Derivative (PID) based controller is developed using LabVIEW (NI) and experiments are performed. Numerical modeling and analysis of the structure is carried out using finite element software ABAQUS. For data reduction and fast computation, stiffness matrix generated by ABAQUS is condensed by Guyan Reduction technique and shape optimization is performed using Non-dominated Sorting Genetic Algorithm (NSGA-II). The matching in comparative study between numerical and experimental set-up shows efficacy of our method. Thereafter, Electro-Magnetic (EM) simulations of the deformed shape is carried out using electromagnetic field simulation, High Frequency Structure Simulator (HFSS). The proposed design is envisaged to be very effective for multipurpose application of satellite system in the future missions of Indian Space Research Organization (ISRO).

Electromagnetic-gravitational energy systems

NASA Technical Reports Server (NTRS)

Schatten, K. H.

1981-01-01

Two methods are considered to 'tap' the earth's rotational energy. This ancient 'collapsed gravitational energy' exceeds the earth-lunar binding energy. One involves an orbiting 'electromagnetic-gravitational' coupling system whereby the earth's rotation, with its nonuniform mass distribution, first uses gravity to add orbital energy to a satellite, similar to a planetary 'flyby'. The second stage involves enhanced satellite 'drag' as current-carrying coils withdraw the added orbital energy as they pass through the earth's nonuniform magnetic field. A second more direct method couples the earth's rotational motion using conducting wires moving through the noncorotating part (ionospheric current systems) of the geomagnetic field. These methods, although not immediately feasible, are considerably more efficient than using pure gravitational coupling to earth-moon tides.

Preliminary environmental assessment for the satellite power system (SPS). Revision 1. Volume 1. Executive summary

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

Not Available

1980-01-01

A preliminary assessment of the environmental impacts of the proposed satellite power system (SPS) is summarized here. In this system, satellites would collect solar energy in space, convert it to microwaves, and transmit the microwaves to receiving antennas (rectennas) on earth. At the rectennas, the microwaves would be converted to electricity. The assessment considers microwave and nonmicrowave effects on the terrestrial environment and human health, atmospheric effects, and disruption of communications and other electromagnetic systems.

KSC-01pp1065

NASA Image and Video Library

2001-06-02

KENNEDY SPACE CENTER, Fla. -- At Complex 36-A, Cape Canaveral Air Force Station, the second stage of the Geostationary Operational Environmental Satellite-M (GOES-M) Atlas II rocket is lifted up the gantry for mating with the first stage. The last in the current series of advanced geostationary weather satellites in service, GOES-M has a new instrument not on earlier spacecraft, a Solar X-ray Imager that can be used in forecasting space weather, the effects of solar storms that create electromagnetic disturbances on earth that affect other satellites, communications and power grids. GOES-M is scheduled to launch from Cape Canaveral Air Force Station July 15

KSC-01pp1066

NASA Image and Video Library

2001-06-02

KENNEDY SPACE CENTER, Fla. -- At Complex 36-A, Cape Canaveral Air Force Station, the second stage of the Geostationary Operational Environmental Satellite-M (GOES-M) Atlas II rocket nears the top of the gantry. It will be mated with the first stage. The last in the current series of advanced geostationary weather satellites in service, GOES-M has a new instrument not on earlier spacecraft, a Solar X-ray Imager that can be used in forecasting space weather, the effects of solar storms that create electromagnetic disturbances on earth that affect other satellites, communications and power grids. GOES-M is scheduled to launch from Cape Canaveral Air Force Station July 15

Wet/Dry Vacuum Cleaner

NASA Technical Reports Server (NTRS)

Reimers, Harold; Andampour, Jay; Kunitser, Craig; Thomas, Ike

1995-01-01

Vacuum cleaner collects and retains dust, wet debris, and liquids. Designed for housekeeping on Space Station Freedom, it functions equally well in normal Earth Gravity or in microgravity. Generates acoustic noise at comfortably low levels and includes circuitry that reduces electromagnetic interference to other electronic equipment. Draws materials into bag made of hydrophobic sheet with layers of hydrophilic super-absorbing pads at downstream end material. Hydrophilic material can gel many times its own weight of liquid. Blower also provides secondary airflow to cool its electronic components.

Anthropogenic Space Weather

NASA Astrophysics Data System (ADS)

Gombosi, T. I.; Baker, D. N.; Balogh, A.; Erickson, P. J.; Huba, J. D.; Lanzerotti, L. J.

2017-11-01

Anthropogenic effects on the space environment started in the late 19th century and reached their peak in the 1960s when high-altitude nuclear explosions were carried out by the USA and the Soviet Union. These explosions created artificial radiation belts near Earth that resulted in major damages to several satellites. Another, unexpected impact of the high-altitude nuclear tests was the electromagnetic pulse (EMP) that can have devastating effects over a large geographic area (as large as the continental United States). Other anthropogenic impacts on the space environment include chemical release experiments, high-frequency wave heating of the ionosphere and the interaction of VLF waves with the radiation belts. This paper reviews the fundamental physical process behind these phenomena and discusses the observations of their impacts.

NASA's Decadal Planning Team Mars Mission Analysis Summary

NASA Astrophysics Data System (ADS)

Drake, Bret G.

2007-02-01

In June 1999 the NASA Administrator chartered an internal NASA task force, termed the Decadal Planning Team, to create new integrated vision and strategy for space exploration. The efforts of the Decadal Planning Team evolved into the Agency-wide team known as the NASA Exploration Team (NEXT). This team was also instructed to identify technology roadmaps to enable the science-driven exploration vision, established a cross-Enterprise, cross-Center systems engineering team with emphasis focused on revolutionary not evolutionary approaches. The strategy of the DPT and NEXT teams was to "Go Anywhere, Anytime" by conquering key exploration hurdles of space transportation, crew health and safety, human/robotic partnerships, affordable abundant power, and advanced space systems performance. Early emphasis was placed on revolutionary exploration concepts such as rail gun and electromagnetic launchers, propellant depots, retrograde trajectories, nano structures, and gas core nuclear rockets to name a few. Many of these revolutionary concepts turned out to be either not feasible for human exploration missions or well beyond expected technology readiness for near-term implementation. During the DPT and NEXT study cycles, several architectures were analyzed including missions to the Earth-Sun Libration Point (L2), the Earth-Moon Gateway and L1, the lunar surface, Mars (both short and long stays), one-year round trip Mars, and near-Earth asteroids. Common emphasis of these studies included utilization of the Earth-Moon Libration Point (L1) as a staging point for exploration activities, current (Shuttle) and near-term launch capabilities (EELV), advanced propulsion, and robust space power. Although there was much emphasis placed on utilization of existing launch capabilities, the team concluded that missions in near-Earth space are only marginally feasible and human missions to Mars were not feasible without a heavy lift launch capability. In addition, the team concluded that missions in Earth s neighborhood, such as to the Moon, can serve as stepping-stones toward further deep-space missions in terms of proving systems, technologies, and operational concepts. The material contained in this presentation was compiled to capture the work performed by the Mars Sub-Team of the DPT NEXT efforts in the late 1999-2001 timeframe.

NASA's Decadal Planning Team Mars Mission Analysis Summary

NASA Technical Reports Server (NTRS)

Drake, Bret G. (Editor)

2007-01-01

In June 1999 the NASA Administrator chartered an internal NASA task force, termed the Decadal Planning Team, to create new integrated vision and strategy for space exploration. The efforts of the Decadal Planning Team evolved into the Agency-wide team known as the NASA Exploration Team (NEXT). This team was also instructed to identify technology roadmaps to enable the science-driven exploration vision, established a cross-Enterprise, cross-Center systems engineering team with emphasis focused on revolutionary not evolutionary approaches. The strategy of the DPT and NEXT teams was to "Go Anywhere, Anytime" by conquering key exploration hurdles of space transportation, crew health and safety, human/robotic partnerships, affordable abundant power, and advanced space systems performance. Early emphasis was placed on revolutionary exploration concepts such as rail gun and electromagnetic launchers, propellant depots, retrograde trajectories, nano structures, and gas core nuclear rockets to name a few. Many of these revolutionary concepts turned out to be either not feasible for human exploration missions or well beyond expected technology readiness for near-term implementation. During the DPT and NEXT study cycles, several architectures were analyzed including missions to the Earth-Sun Libration Point (L2), the Earth-Moon Gateway and L1, the lunar surface, Mars (both short and long stays), one-year round trip Mars, and near-Earth asteroids. Common emphasis of these studies included utilization of the Earth-Moon Libration Point (L1) as a staging point for exploration activities, current (Shuttle) and near-term launch capabilities (EELV), advanced propulsion, and robust space power. Although there was much emphasis placed on utilization of existing launch capabilities, the team concluded that missions in near-Earth space are only marginally feasible and human missions to Mars were not feasible without a heavy lift launch capability. In addition, the team concluded that missions in Earth s neighborhood, such as to the Moon, can serve as stepping-stones toward further deep-space missions in terms of proving systems, technologies, and operational concepts. The material contained in this presentation was compiled to capture the work performed by the Mars Sub-Team of the DPT NEXT efforts in the late 1999-2001 timeframe.

Sizing and Pointing of Solar Panels and for Solar Thermal Applications

Atmospheric Science Data Center

2014-09-25

... on horizontal surface (kWh/m2/day) Amount of electromagnetic energy (solar radiation) incident on the surface of the earth. ... on horizontal surface (kWh/m2/day) Amount of electromagnetic energy (solar radiation) incident on the surface of the earth ...

Communications technology

NASA Astrophysics Data System (ADS)

Sokoloski, Martin M.

1988-09-01

The objective of the Communications Technology Program is to enable data transmission to and from low Earth orbit, geostationary orbit, and solar and deep space missions. This can be achieved by maintaining an effective, balances effort in basic, applied, and demonstration prototype communications technology through work in theory, experimentation, and components. The program consists of three major research and development discipline areas which are: microwave and millimeter wave tube components; solid state monolithic integrated circuit; and free space laser communications components and devices. The research ranges from basic research in surface physics (to study the mechanisms of surface degradation from under high temperature and voltage operating conditions which impacts cathode tube reliability and lifetime) to generic research on the dynamics of electron beams and circuits (for exploitation in various micro- and millimeter wave tube devices). Work is also performed on advanced III-V semiconductor materials and devices for use in monolithic integrated analog circuits (used in adaptive, programmable phased arrays for microwave antenna feeds and receivers) - on the use of electromagnetic theory in antennas and on technology necessary for eventual employment of lasers for free space communications for future low earth, geostationary, and deep space missions requiring high data rates with corresponding directivity and reliability.

Communications technology

NASA Technical Reports Server (NTRS)

Sokoloski, Martin M.

1988-01-01

The objective of the Communications Technology Program is to enable data transmission to and from low Earth orbit, geostationary orbit, and solar and deep space missions. This can be achieved by maintaining an effective, balances effort in basic, applied, and demonstration prototype communications technology through work in theory, experimentation, and components. The program consists of three major research and development discipline areas which are: microwave and millimeter wave tube components; solid state monolithic integrated circuit; and free space laser communications components and devices. The research ranges from basic research in surface physics (to study the mechanisms of surface degradation from under high temperature and voltage operating conditions which impacts cathode tube reliability and lifetime) to generic research on the dynamics of electron beams and circuits (for exploitation in various micro- and millimeter wave tube devices). Work is also performed on advanced III-V semiconductor materials and devices for use in monolithic integrated analog circuits (used in adaptive, programmable phased arrays for microwave antenna feeds and receivers) - on the use of electromagnetic theory in antennas and on technology necessary for eventual employment of lasers for free space communications for future low earth, geostationary, and deep space missions requiring high data rates with corresponding directivity and reliability.

How to use the Sun-Earth Lagrange points for fundamental physics and navigation

NASA Astrophysics Data System (ADS)

Tartaglia, A.; Lorenzini, E. C.; Lucchesi, D.; Pucacco, G.; Ruggiero, M. L.; Valko, P.

2018-01-01

We illustrate the proposal, nicknamed LAGRANGE, to use spacecraft, located at the Sun-Earth Lagrange points, as a physical reference frame. Performing time of flight measurements of electromagnetic signals traveling on closed paths between the points, we show that it would be possible: (a) to refine gravitational time delay knowledge due both to the Sun and the Earth; (b) to detect the gravito-magnetic frame dragging of the Sun, so deducing information about the interior of the star; (c) to check the possible existence of a galactic gravitomagnetic field, which would imply a revision of the properties of a dark matter halo; (d) to set up a relativistic positioning and navigation system at the scale of the inner solar system. The paper presents estimated values for the relevant quantities and discusses the feasibility of the project analyzing the behavior of the space devices close to the Lagrange points.

Finding 'paydirt' on the moon and asteroids

NASA Technical Reports Server (NTRS)

Staehle, R. L.

1983-01-01

Lunar polar region water ice, the Trojan asteroids of the earth, accessible, volatile substance-rich near-earth asteroids, and lunar gas deposits, are theoretically identified extraterrestrial resources for application to space transportation whose existence and economical exploitability could be confirmed by explorations conducted with relatively simple spacecraft. Any of these resources could improve the economics of interorbit transportation, thereby permitting launch vehicle payloads to be devoted to the transport of revenue-generating or services-providing equipment, rather than to the large propellant volumes required for the placing of large payloads on station. Among the verification missions cited is a simple lunar prospector orbiter, carrying a gamma-ray spectrometer and an electromagnetic sounder, which could ascertain the presence of water ice at the lunar poles.

Cosmic Rays as a Factor of Biospheric Evolution

NASA Astrophysics Data System (ADS)

Miroshnichenko, L. I.

2014-10-01

There are no doubts that the Earth's space environment in the past inevitably has exerted direct and/or indirect influence [1-4] on the conditions of terrestrial life and biospheric evolution. Well-known space factors are usually the fluxes of cosmic dust and gas, comets and asteroids, cosmic rays (energetic particles of galactic and/or solar origin), interplanetary plasma (solar wind) and electromagnetic radiation of different energies, wave lengths, or frequencies. Of great interest are radiation conditions and their variations, especially in the remote past (over the geological time scales). The Sun, the most important and indispensable condition for the existence of the Earth's biosphere, is also a potential source of dangerous emissions. In continuation of (and in addition to) our review paper [3], below we summarize the observational data and results of theoretical works that have been carried out and/or published mainly after 2012. These studies are actually in the frontier region between the Astrobiology and Space Weather. Our main attention is paid to cosmic rays (CR) of galactic and solar origin (GCR and SCR, respectively).

Lunar Gravity-Assist Maneuver As a Way of Reducing the Orbit Amplitude in the Spectrum-Röntgen-Gamma Project

NASA Astrophysics Data System (ADS)

Kovalenko, I. D.; Eismont, N. A.

2018-04-01

Spectrum-Röntgen-Gamma (SRG) is a space observatory designed to observe astrophysical objects in the X-ray range of the electromagnetic spectrum. SRG is planned to be launched in 2019 by a Proton-M launch vehicle with a DM3 upper stage. The spacecraft will be delivered to an orbit around the Sun-Earth collinear libration point L2 located at a distance of 1.5 million km from the Earth. Although the SRG launch scheme has already been determined at present, in this paper we consider an alternative spacecraft transfer scenario using a lunar gravity-assist maneuver. The proposed scenario allows a oneimpulse transfer from a low Earth orbit to a small-amplitude orbit around the libration point to be performed while fulfilling the technical constraints and the scientific requirements of the mission.

Microstructural Characterization of Polymers with Positrons

NASA Technical Reports Server (NTRS)

Singh, Jag J.

1997-01-01

Positrons provide a versatile probe for monitoring microstructural features of molecular solids. In this paper, we report on positron lifetime measurements in two different types of polymers. The first group comprises polyacrylates processed on earth and in space. The second group includes fully-compatible and totally-incompatible Semi-Interpenetrating polymer networks of thermosetting and thermoplastic polyimides. On the basis of lifetime measurements, it is concluded that free volumes are a direct reflection of physical/electromagnetic properties of the host polymers.

The interaction of ultra-low-frequency pc3-5 waves with charged particles in Earth's magnetosphere

NASA Astrophysics Data System (ADS)

Zong, Qiugang; Rankin, Robert; Zhou, Xuzhi

2017-12-01

One of the most important issues in space physics is to identify the dominant processes that transfer energy from the solar wind to energetic particle populations in Earth's inner magnetosphere. Ultra-low-frequency (ULF) waves are an important consideration as they propagate electromagnetic energy over vast distances with little dissipation and interact with charged particles via drift resonance and drift-bounce resonance. ULF waves also take part in magnetosphere-ionosphere coupling and thus play an essential role in regulating energy flow throughout the entire system. This review summarizes recent advances in the characterization of ULF Pc3-5 waves in different regions of the magnetosphere, including ion and electron acceleration associated with these waves.

Research in space physics at the University of Iowa, 1982

NASA Technical Reports Server (NTRS)

Vanallen, J. A.; Frank, L. A.; Gurnett, D. A.; Shawhan, S. D.; Robison, E. D.; Robertson, T. D.

1983-01-01

The energetic particles and the electric, magnetic, and electromagnetic fields associated with the Earth, the Sun, the Moon, the planets, comets, and the interplanetary medium are examined. Matters under current investigation are following: energetic particles trapped in the Earth's magnetic field, origin and propagation of very low frequency radio waves and electrostatic, the magnetospheres of Jupiter, Saturn and prospectively Uranus and Neptune, diffusion of energetic particles in Saturn's magnetosphere, radio emissions from Jupiter and Saturn, solar modulation and the heliocentric radial dependence of the intensity of galactic cosmic rays, interplanetary propagation and acceleration of energetic particles, the theory of wave phenomena in turbulent plasmas, and basic wave-particle-chemical processes in the ionospheric plasma.

Legal Implications of Nuclear Propulsion for Space Objects

NASA Astrophysics Data System (ADS)

Pop, V.

2002-01-01

This paper is intended to examine nuclear propulsion concepts such as "Project Orion", "Project Daedalus", NERVA, VASIMIR, from the legal point of view. The UN Principles Relevant to the Use of Nuclear Power Sources in Outer Space apply to nuclear power sources in outer space devoted to the generation of electric power on board space objects for non-propulsive purposes, and do not regulate the use of nuclear energy as a means of propulsion. However, nuclear propulsion by means of detonating atomic bombs (ORION) is, in principle, banned under the 1963 Treaty Banning Nuclear Weapon Tests in the Atmosphere, in Outer Space, and Under Water. The legality of use of nuclear propulsion will be analysed from different approaches - historical (i.e. the lawfulness of these projects at the time of their proposal, at the present time, and in the future - in the light of the mutability and evolution of international law), spatial (i.e. the legal regime governing peaceful nuclear explosions in different spatial zones - Earth atmosphere, Earth orbit, Solar System, and interstellar space), and technical (i.e, the legal regime applicable to different nuclear propulsion techniques, and to the various negative effects - e.g. damage to other space systems as an effect of the electromagnetic pulse, etc). The paper will analyse the positive law, and will also come with suggestions "de lege ferenda".

Using a small hybrid pulse power transformer unit as component of a high-current opening switch for a railgun

NASA Astrophysics Data System (ADS)

Leung, E. M. W.; Bailey, R. E.; Michels, P. H.

1989-03-01

The hybrid pulse power transformer (HPPT) is a unique concept utilizing the ultrafast superconducting-to-normal transition process of a superconductor. When used in the form of a hybrid transformer current-zero switch (HTCS), this creates an approach in which the large, high-power, high-current opening switch in a conventional railgun system can be eliminated. This represents an innovative application of superconductivity to pulsed power conditioning required for the Strategic Defense Initiative (SDI). The authors explain the working principles of a 100-KJ unit capable of switching up to 500 kA at a frequency of 0.5 Hz and with a system efficiency of greater than 90 percent. Circuit analysis using a computer code called SPICE PLUS was used to verify the HTCS concept. This concept can be scaled up to applications in the several mega-ampere levels.

Dynamics of a Finite Liquid Oxygen (LOX) Column in a Pulsed Magnetic Field

NASA Technical Reports Server (NTRS)

Youngquist, Robert; Immer, Christopher; Lane, John; Simpson, James; Steinrock, T. (Technical Monitor)

2002-01-01

It is well known that liquid oxygen has a sufficient paramagnetic susceptibility that a strong magnetic field gradient can lift it in the earth's gravitational field. The movement of liquid oxygen is vital to the space program since it one of the primary oxidizers used for propulsion. Transport of liquid oxygen (LOX) via direct interaction of the magnetic fields (B field) with the fluid is a current topic of research and development at Kennedy Space Center, FL. This method of transporting (i.e. pumping) LOX may have particular advantages on Mars and other reduced gravitational environments, namely safety and reliability. This paper will address transport of a magnetic fluid, LOX, via phased-pulsed electromagnets acting on the edge of the column of fluid. The authors have developed a physical model from first-principles for the motion of a magnetic fluid in a particular U-tube geometry subjected to a pulsed magnetic field from an arbitrary solenoidal electromagnet. Experimental data that have been collected from the analogous geometry correlate well to that of the ab-initio calculations.

Basic principles of coaxial launch technology

NASA Technical Reports Server (NTRS)

Kolm, H.; Mongeau, P.

1984-01-01

Already in the 1930s, a discrete-coil mechanically synchronized launcher was built. At the present time, research is almost entirely directed towards railguns. However, although coaxial accelerators are more complex than railguns, they have certain unique advantages. Some of these advantages are related to the absence of physical contact requirements with the projectile, the possibility of a scale-up to very large projectile size, and the availability of up to 100 times more thrust for a given current. The price of the advantages is the need for a drive current in the form of pulses synchronized precisely with transit of each projectile coil through each drive coil. At high velocities, high voltages are required, and high voltage switching represents the technology limit on launch velocity. Attention is given to inductance gradients, the double hump, methods of excitation, methods of synchronization, projectile configuration, energy supply, fundamental limits, trends, and research needs.

KSC-01pp1064

NASA Image and Video Library

2001-06-02

KENNEDY SPACE CENTER, Fla. -- At Complex 36-A, Cape Canaveral Air Force Station, the second stage of the Geostationary Operational Environmental Satellite-M (GOES-M) Atlas II rocket is lifted from the transporter. It will be raised to vertical and lifted up the gantry for mating with the first stage. The last in the current series of advanced geostationary weather satellites in service, GOES-M has a new instrument not on earlier spacecraft, a Solar X-ray Imager that can be used in forecasting space weather, the effects of solar storms that create electromagnetic disturbances on earth that affect other satellites, communications and power grids. GOES-M is scheduled to launch from Cape Canaveral Air Force Station July 15

Electromagnetic Scattering Analysis of Large Size Asteroids/Comets for Reflection/Transmission Tomography (RTT)

NASA Technical Reports Server (NTRS)

Deshpande, Manohar

2011-01-01

A precise knowledge of the interior structure of asteroids, comets, and Near Earth Objects (NEO) is important to assess the consequences of their impacts with the Earth and develop efficient mitigation strategies. Knowledge of their interior structure also provides opportunities for extraction of raw materials for future space activities. Low frequency radio sounding is often proposed for investigating interior structures of asteroids and NEOs. For designing and optimizing radio sounding instrument it is advantageous to have an accurate and efficient numerical simulation model of radio reflection and transmission through large size bodies of asteroid shapes. In this presentation we will present electromagnetic (EM) scattering analysis of electrically large size asteroids using (1) a weak form formulation and (2) also a more accurate hybrid finite element method/method of moments (FEM/MOM) to help estimate their internal structures. Assuming the internal structure with known electrical properties of a sample asteroid, we first develop its forward EM scattering model. From the knowledge of EM scattering as a function of frequency and look angle we will then present the inverse scattering procedure to extract its interior structure image. Validity of the inverse scattering procedure will be presented through few simulation examples.

Electronic systems failures and anomalies attributed to electromagnetic interference

NASA Technical Reports Server (NTRS)

Leach, R. D. (Editor); Alexander, M. B. (Editor)

1995-01-01

The effects of electromagnetic interference can be very detrimental to electronic systems utilized in space missions. Assuring that subsystems and systems are electrically compatible is an important engineering function necessary to assure mission success. This reference publication will acquaint the reader with spacecraft electronic systems failures and anomalies caused by electromagnetic interference and will show the importance of electromagnetic compatibility activities in conjunction with space flight programs. It is also hoped that the report will illustrate that evolving electronic systems are increasingly sensitive to electromagnetic interference and that NASA personnel must continue to diligently pursue electromagnetic compatibility on space flight systems.

Spontaneous magnetic fluctuations and collisionless regulation of the Earth's plasma sheet

NASA Astrophysics Data System (ADS)

Moya, P. S.; Espinoza, C.; Stepanova, M. V.; Antonova, E. E.; Valdivia, J. A.

2017-12-01

Even in the absence of instabilities, plasmas often exhibit inherent electromagnetic fluctuations which are present due to the thermal motion of charged particles, sometimes called thermal (quasi-thermal) noise. One of the fundamental and challenging problems of laboratory, space, and astrophysical plasma physics is the understanding of the relaxation processes of nearly collisionless plasmas, and the resultant state of electromagnetic plasma turbulence. The study of thermal fluctuations can be elegantly addressed by using the Fluctuation-Dissipation Theorem that describes the average amplitude of the fluctuations through correlations of the linear response of the media with the perturbations of the equilibrium state (the dissipation). Recently, it has been shown that solar wind plasma beta and temperature anisotropy observations are bounded by kinetic instabilities such as the ion cyclotron, mirror, and firehose instabilities. The magnetic fluctuations observed within the bounded area are consistent with the predictions of the Fluctuation-Dissipation theorem even far below the kinetic instability thresholds, with an enhancement of the fluctuation level near the thresholds. Here, for the very first time, using in-situ magnetic field and plasma data from the THEMIS spacecraft, we show that such regulation also occurs in the Earth's plasma sheet at the ion scales and that, regardless of the clear differences between the solar wind and the magnetosphere environments, spontaneous fluctuation and their collisionless regulation seem to be fundamental features of space and astrophysical plasmas, suggesting the universality of the processes.

The astrobiological mission EXPOSE-R on board of the International Space Station

NASA Astrophysics Data System (ADS)

Rabbow, Elke; Rettberg, Petra; Barczyk, Simon; Bohmeier, Maria; Parpart, Andre; Panitz, Corinna; Horneck, Gerda; Burfeindt, Jürgen; Molter, Ferdinand; Jaramillo, Esther; Pereira, Carlos; Weiß, Peter; Willnecker, Rainer; Demets, René; Dettmann, Jan

2015-01-01

EXPOSE-R flew as the second of the European Space Agency (ESA) EXPOSE multi-user facilities on the International Space Station. During the mission on the external URM-D platform of the Zvezda service module, samples of eight international astrobiology experiments selected by ESA and one Russian guest experiment were exposed to low Earth orbit space parameters from March 10th, 2009 to January 21st, 2011. EXPOSE-R accommodated a total of 1220 samples for exposure to selected space conditions and combinations, including space vacuum, temperature cycles through 273 K, cosmic radiation, solar electromagnetic radiation at >110, >170 or >200 nm at various fluences up to GJ m-2. Samples ranged from chemical compounds via unicellular organisms and multicellular mosquito larvae and seeds to passive radiation dosimeters. Additionally, one active radiation measurement instrument was accommodated on EXPOSE-R and commanded from ground in accordance with the facility itself. Data on ultraviolet radiation, cosmic radiation and temperature were measured every 10 s and downlinked by telemetry and data carrier every few months. The EXPOSE-R trays and samples returned to Earth on March 9th, 2011 with Shuttle flight, Space Transportation System (STS)-133/ULF 5, Discovery, after successful total mission duration of 27 months in space. The samples were analysed in the individual investigators laboratories. A parallel Mission Ground Reference experiment was performed on ground with a parallel set of hardware and samples under simulated space conditions following to the data transmitted from the flight mission.

Cosmic Rays as a Factor of Biosphere Evolution

NASA Astrophysics Data System (ADS)

Miroshnichenko, L. I.

2014-11-01

There are no doubts that the Earth's space environment in the past inevitably exerted direct and/or indirect influence [1--4] on the conditions of terrestrial life and biospheric evolution. Well-known cosmic factors are usually streams of cosmic dust and gas, comets and asteroids, cosmic rays (energetic particles of galactic and/or solar origin), interplanetary plasma (solar wind), and electromagnetic radiation of different energies, wavelengths, or frequencies. Of great interest are radiation conditions and their variations, especially in the remote past (over the geological time scales). The Sun, the most important and indispensable condition for the existence of the Earth's biosphere, is also a potential source of dangerous emissions. In continuation of (and in addition to) our review paper [3], below we summarize the observational data and results of theoretical works that have been carried out and/or published mainly after 2012. These studies are actually in the frontier region between the Astrobiology and Space Weather. Our main attention is paid to cosmic rays (CR) of galactic and solar origin (GCR and SCR, respectively).

An interpretation of the 1997 airborne electromagnetic (AEM) survey, Fort Huachuca vicinity, Cochise County, Arizona

USGS Publications Warehouse

Bultman, Mark W.; Gettings, Mark E.; Wynn, Jeff

1999-01-01

In March of 1997, an airborne electromagnetic (AEM) survey of the Fort Huachuca Military Reservation and immediate surrounds was conducted. This survey was sponsored by the U.S. Army and contracted through the Geologic Division of the U.S. Geological Survey (USGS). Data were gathered by Geoterrex-Dighem Ltd. of Ottawa, Canada. The survey aircraft is surrounded by a coil through which a large current pulse is passed. This pulse induces currents in the Earth which are recorded by a set of three mutually perpendicular coils towed in a "bird" about 100 m behind and below the aircraft. The bird also records the Earth's magnetic field. The system samples the Earth response to the electromagnetic pulse about every 16 m along the aircraft flight path. For this survey, the bulk of the flightpaths were spaced about 400 m apart and oriented in a northeast-southwest direction extending from bedrock over the Huachuca Mountains to bedrock over the Tombstone Hills. A preliminary report on the unprocessed data collected in the field was delivered to the U.S. Army by USGS in July 1997 (USGS Open-File Report 97–457). The final data were delivered in March, 1998 by the contractor to USGS and thence to the U.S. Army. The present report represents the final interpretive report from USGS. The objectives of the survey were to: 1) define the structure of the San Pedro basin in the Sierra Vista-Fort Huachuca-Huachuca City area, including the depth and shape of the basin, and to delineate large faults that may be active within the basin fill and therefore important in the hydrologic regime; 2) define near surface and subsurface areas that contain a large volume fraction of silt and clay in the basin fill and which both reduce the volume of available storage for water and reduce the permeability of the aquifer; and 3) to evaluate the use of the time domain electromagnetic method in the southwest desert setting as a means of mapping depth to water.

Astronomy and Space Science from the Moon: Proceedings of Symposium E4 of the COSPAR 29th Plenary Meeting held in Washington, DC, 28 Aug.-5 Sep., 1992

NASA Technical Reports Server (NTRS)

Foing, B. H. (Editor)

1994-01-01

The goal of the conference was to assess the moon as a base for conducting astronomy, solar system observations, and space sciences. The lunar vacuum allows a complete opening of the electromagnetic window and distortion-free measurements at the highest angular resolution, precision, and temporal stability. The moon is perfect for continuous monitoring of the Sun, Solar System targets, and for deep observations of galactic and extragalactic objects. It is an in-situ laboratory for selenophysics, chemistry, and exobiology. The moon contains useful resources and is accessible from Earth for installation, operations maintenance, robotics, and human activities.

Courses and Resources to Teach Space Physics to Standards

NASA Astrophysics Data System (ADS)

Reiff, P. H.

2008-12-01

We have created four courses for teachers, and inquiry-based materials to go with them, that embed space physics concepts while teaching Space Physics to National and State standards. The state of Texas recently adopted a "4x4" standard, which makes the "recommended" graduation requirement for high school students to include four science and four math courses. Space Physics is not specifically listed as a topic, but falls naturally as part of three of the Texas High School courses: "Physics", "Astronomy" and "Earth and Space Science", a new course whose syllabus is being decided now. The national standards which are most relevant at the high school level are "Change, Constancy and Measurement", "Motions and Forces", "Interactions of Energy and Matter" and "Natural and Human-induced hazards" [National Science Ed Standards, 1996]. The "Texas Essential Knowledge and Skills" includes circuits, electricity and magnetism, and waves in their Physics course syllabus, and include "describe the Sun's effects on the Earth" in the Astronomy class. In the new Earth and Space Science class we expect that additional heliospheric concepts will be included. At Rice we have four Astronomy courses (and four Earth Science courses) for teachers, two of which involve a substantial space physics content. By taking those eight courses, plus a research project and another content or education elective, the teachers can earn a "Masters of Science Teaching" degree. In "Teaching Earth and Space Science" (ASTR 402) we dedicate about 4 weeks on the Sun and the Earth and its environment. The "Physics of Ham Radio" course (PHYS 401) has an even more relevant focus. That class introduces electricity and magnetism, with hands-on activities on circuits and electromagnetic waves. The students earn their "Technician" class amateur license by making at least 75 per cent on the first quiz, which allows them VHF and UHF broadcast privileges. The second half of the course covers more space weather topics including the ionosphere, solar activity, radio propagation and absorption, antennas, etc. Some students pass the more detailed "General" amateur license by the end of the semester, which allows them to transmit at HF frequencies. Ham radio clubs are becoming more interesting to students as internet-based and digital modes allow more extensive communication even with minimum licensing, and amateur radio clubs are an excellent resource to teachers who want to set up a station in their school. A Technician license can also allow even communication with the Space Station.

Research and technology, 1990: Goddard Space Flight Center

NASA Technical Reports Server (NTRS)

1990-01-01

Goddard celebrates 1990 as a banner year in space based astronomy. From above the Earth's obscuring atmosphere, four major orbiting observatories examined the heavens at wavelengths that spanned the electromagnetic spectrum. In the infrared and microwave, the Cosmic Background Explorer (COBE), measured the spectrum and angular distribution of the cosmic background radiation to extraordinary precision. In the optical and UV, the Hubble Space Telescope has returned spectacular high resolution images and spectra of a wealth of astronomical objects. The Goddard High Resolution Spectrograph has resolved dozens of UV spectral lines which are as yet unidentified because they have never before been seen in any astronomical spectrum. In x rays, the Roentgen Satellite has begun returning equally spectacular images of high energy objects within our own and other galaxies.

Microstructural Characterization of Polymers by Positron Lifetime Spectroscopy

NASA Technical Reports Server (NTRS)

Singh, Jag J.

1996-01-01

Positrons provide a versatile probe for monitoring microstructural features of molecular solids. In this paper, we report on positron lifetime measurements in two different types of polymers. The first group comprises polyacrylates processed on earth and in space. The second group includes fully-compatible and totally-incompatible Semi-Interpenetrating polymer networks of thermosetting and thermoplastic polyimides. On the basis of lifetime measurements, it is concluded that free volumes are a direct reflection of physical/electromagnetic properties of the host polymers.

USSR Report Earth Sciences Tables of Contents JPRS-UES-86-001, 10 January 1986-JPRS-UES-86-008, 4 December 1986.

DTIC Science & Technology

1987-03-27

Research Ship ’Shuleykin’ in Studies of Arctic Seas (B. Moiseyev; VODNYY TRANSPORT, 7 Sep 85) l6 Scanning Submersible Craft Tested From Research...Data Bank can Process Satellite Signals (NTR: PROBLEMY I RESHENIYA, No 9, 17 Sep-7 Oct 1985) 13 Trials of Manned Submersible Craft ’Osmotr’ (I...Specifics of Electromagnetic Field of Multiple- Spaced Arrays of Frequency Sounding and Resistivity Detectors Over Horst (A.N. Kuznetsov; IZVESTIYA

Demonstration of Electro-Osmotic Pulse Technology in Earth-Covered Magazines at Fort A.P. Hill, VA

DTIC Science & Technology

2009-08-01

Electromagnetic Radiation to Ordnance ( HERO ) Evaluation Tests were conducted on magazines to detect any radio frequency (RF) emissions produced and to...measure electromagnetic (EM) radiation from the anodes installed in the magazines. The detailed results of a HERO ( Hazards of Electromagnetic ...reinforcement steel ........................................................... 14 3.3.6 Testing for electromagnetic radiation hazards

Measuring Solar Radiation Incident on Earth: Solar Constant-3 (SOLCON-3)

NASA Technical Reports Server (NTRS)

Crommelynck, Dominique; Joukoff, Alexandre; Dewitte, Steven

2002-01-01

Life on Earth is possible because the climate conditions on Earth are relatively mild. One element of the climate on Earth, the temperature, is determined by the heat exchanges between the Earth and its surroundings, outer space. The heat exchanges take place in the form of electromagnetic radiation. The Earth gains energy because it absorbs solar radiation, and it loses energy because it emits thermal infrared radiation to cold space. The heat exchanges are in balance: the heat gained by the Earth through solar radiation equals the heat lost through thermal radiation. When the balance is perturbed, a temperature change and hence a climate change of the Earth will occur. One possible perturbation of the balance is the CO2 greenhouse effect: when the amount of CO2 in the atmosphere increases, this will reduce the loss of thermal infrared radiation to cold space. Earth will gain more heat and hence the temperature will rise. Another perturbation of the balance can occur through variation of the amount of energy emitted by the sun. When the sun emits more energy, this will directly cause a rise of temperature on Earth. For a long time scientists believed that the energy emitted by the sun was constant. The 'solar constant' is defined as the amount of solar energy received per unit surface at a distance of one astronomical unit (the average distance of Earth's orbit) from the sun. Accurate measurements of the variations of the solar constant have been made since 1978. From these we know that the solar constant varies approximately with the 11-year solar cycle observed in other solar phenomena, such as the occurrence of sunspots, dark spots that are sometimes visible on the solar surface. When a sunspot occurs on the sun, since the spot is dark, the radiation (light) emitted by the sun drops instantaneously. Oddly, periods of high solar activity, when a lot of sunspot numbers increase, correspond to periods when the average solar constant is high. This indicates that the background on which the sunspots occur becomes brighter during high solar activity.

SELF and VLF electromagnetic emissions that preceded the M6.2 Central Italy earthquake occurred on August 24, 2016

NASA Astrophysics Data System (ADS)

Cataldi, Daniele; Cataldi, Gabriele; Straser, Valentino

2017-04-01

On August 24, 2016 at 01:36:32 UTC a destructive earthquake hit Central Italy with a magnitude of M6.2. The authors of this study have recorded some electromagnetic signals that have preceded this strong earthquake. These signals were recorded through two electromagnetic monitoring stations realized by Gabriele Cataldi and Daniele Cataldi, located near the town of Albano Laziale (Rome, Italy) and near the city of Lariano (Rome, Italy) and can monitor the radio spectrum 24h7 between 0.001 Hz and 96 kHz (SELF-LF band). The electromagnetic monitoring allowed to identify two interesting types of electromagnetic anomalies: the first electromagnetic anomaly was recorded on August 18, 2016 between 02:47 UTC and 06:21 UTC, in the VLF band prevalently between 18kHz and 26kHz; the second electromagnetic anomaly was registered between 08:00 UTC on August 23, 2016 and 05:00 UTC on August 24, 2016, prevalently between 0.01 and 0.7Hz: the most intense signals were recorded at 08:50 UTC on August 23, 2016 and approximately 1 hour before the strong earthquake. The Earth's electromagnetic background monitoring in the SELF-VLF band (0Hz

Prospects for Measuring Planetary Spin and Frame-Dragging in Spacecraft Timing Signals

NASA Astrophysics Data System (ADS)

Schärer, Andreas; Bondarescu, Ruxandra; Saha, Prasenjit; Angélil, Raymond; Helled, Ravit; Jetzer, Philippe

2017-09-01

Satellite tracking involves sending electromagnetic signals to Earth. Both the orbit of the spacecraft and the electromagnetic signals themselves are affected by the curvature of spacetime. The arrival time of the pulses is compared to the ticks of local clocks to reconstruct the orbital path of the satellite to high accuracy, and implicitly measure general relativistic effects. In particular, Schwarzschild space curvature (static) and frame-dragging (stationary) due to the planet's spin affect the satellite's orbit. The dominant relativistic effect on the path of the signal photons is Shapiro delays due to static space curvature. We compute these effects for some current and proposed space missions, using a Hamiltonian formulation in four dimensions. For highly eccentric orbits, such as in the Juno mission and in the Cassini Grand Finale, the relativistic effects have a kick-like nature, which could be advantageous for detecting them if their signatures are properly modeled as functions of time. Frame-dragging appears, in principle, measurable by Juno and Cassini, though not by Galileo 5 and 6. Practical measurement would require disentangling frame-dragging from the Newtonian "foreground" such as the gravitational quadrupole which has an impact on both the spacecraft's orbit and the signal propagation. The foreground problem remains to be solved.

Angular momentum and torque described with the complex octonion

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

Weng, Zi-Hua, E-mail: xmuwzh@xmu.edu.cn

2014-08-15

The paper aims to adopt the complex octonion to formulate the angular momentum, torque, and force etc in the electromagnetic and gravitational fields. Applying the octonionic representation enables one single definition of angular momentum (or torque, force) to combine some physics contents, which were considered to be independent of each other in the past. J. C. Maxwell used simultaneously two methods, the vector terminology and quaternion analysis, to depict the electromagnetic theory. It motivates the paper to introduce the quaternion space into the field theory, describing the physical feature of electromagnetic and gravitational fields. The spaces of electromagnetic field andmore » of gravitational field can be chosen as the quaternion spaces, while the coordinate component of quaternion space is able to be the complex number. The quaternion space of electromagnetic field is independent of that of gravitational field. These two quaternion spaces may compose one octonion space. Contrarily, one octonion space can be separated into two subspaces, the quaternion space and S-quaternion space. In the quaternion space, it is able to infer the field potential, field strength, field source, angular momentum, torque, and force etc in the gravitational field. In the S-quaternion space, it is capable of deducing the field potential, field strength, field source, current continuity equation, and electric (or magnetic) dipolar moment etc in the electromagnetic field. The results reveal that the quaternion space is appropriate to describe the gravitational features, including the torque, force, and mass continuity equation etc. The S-quaternion space is proper to depict the electromagnetic features, including the dipolar moment and current continuity equation etc. In case the field strength is weak enough, the force and the continuity equation etc can be respectively reduced to that in the classical field theory.« less

KSC-01pp1020

NASA Image and Video Library

2001-05-23

The newest Geostationary Operational Environmental Satellite-M (GOES-M) satellite is rotated at Astrotech, in Titusville for the media who are there to see the last in the current series of advanced geostationary weather satellites in service. GOES-M has a new instrument not on earlier spacecraft, a Solar X-ray Imager that can be used in forecasting space weather, the effects of solar storms that create electromagnetic disturbances on earth that affect other satellites, communications and power grids. GOES is scheduled to launch from Cape Canaveral Air Force Station on an Atlas II rocket in July

KSC-01pp1021

NASA Image and Video Library

2001-05-23

The newest Geostationary Operational Environmental Satellite-M (GOES-M) satellite is in the spotlight at Astrotech, in Titusville, for the media to see the last in the current series of advanced geostationary weather satellites in service. GOES-M has a new instrument not on earlier spacecraft, a Solar X-ray Imager that can be used in forecasting space weather, the effects of solar storms that create electromagnetic disturbances on earth that affect other satellites, communications and power grids. GOES is scheduled to launch from Cape Canaveral Air Force Station on an Atlas II rocket in July

KSC-01pp1019

NASA Image and Video Library

2001-05-23

The newest Geostationary Operational Environmental Satellite-M (GOES-M) satellite is ready at Astrotech, in Titusville for the media to see the last in the current series of advanced geostationary weather satellites in service. GOES-M has a new instrument not on earlier spacecraft, a Solar X-ray Imager that can be used in forecasting space weather, the effects of solar storms that create electromagnetic disturbances on earth that affect other satellites, communications and power grids. GOES is scheduled to launch from Cape Canaveral Air Force Station on an Atlas II rocket in July

Development and implementation of the software for visualization and analysis of data geophysical loggers

NASA Astrophysics Data System (ADS)

Gordeev, V. F.; Malyshkov, S. Yu.; Botygin, I. A.; Sherstnev, V. S.; Sherstneva, A. I.

2017-11-01

The general trend of modern ecological geophysics is changing priorities towards rapid assessment, management and prediction of ecological and engineering soil stability as well as developing brand new geophysical technologies. The article describes researches conducted by using multi-canal geophysical logger MGR-01 (developed by IMCES SB RAS), which allows to measure flux density of very low-frequency electromagnetic radiation. It is shown that natural pulsed electromagnetic fields of the earthen lithosphere can be a source of new information on Earth's crust and processes in it, including earthquakes. The device is intended for logging electromagnetic processes in Earth's crust, geophysical exploration, finding structural and lithological inhomogeneities, monitoring the geodynamic movement of Earth's crust, express assessment of seismic hazards. The data is gathered automatically from observation point network in Siberia

Tracking Electromagnetic Energy With SQUIDs

NASA Technical Reports Server (NTRS)

2005-01-01

A superconducting quantum interference device (SQUID) is a gadget used to measure extremely weak signals, specifically magnetic flux. It can detect subtle changes in energy, up to 100 billion times weaker than the electromagnetic energy required to move a compass needle. SQUIDs are used for a variety of testing procedures where extreme sensitivity is required and where the test instrument need not come into direct contact with the test subject. NASA uses SQUIDs for remote, noncontact sensing in a variety of venues, including monitoring the Earth s magnetic field and tracking brain activity of pilots. Scientists at NASA s Goddard Space Flight Center have been making extensive use of this technology, from astrophysical research, to tracking the navigational paths of bees in flight to determine if they are using internal compasses. These very sensitive measurement devices have a wide variety of uses within NASA and even more uses within the commercial realm.

The gravitational redshift of a optical vortex being different from that of an gravitational redshift plane of an electromagnetic wave

NASA Astrophysics Data System (ADS)

Portnov, Yuriy A.

2018-06-01

A hypothesis put forward in late 20th century and subsequently substantiated experimentally posited the existence of optical vortices (twisted light). An optical vortex is an electromagnetic wave that in addition to energy and momentum characteristic of flat waves also possesses angular momentum. In recent years optical vortices have found wide-ranging applications in a number of branches including cosmology. The main hypothesis behind this paper implies that the magnitude of gravitational redshift for an optical vortex will differ from the magnitude of gravitational redshift for flat light waves. To facilitate description of optical vortices, we have developed the mathematical device of gravitational interaction in seven-dimensional time-space that we apply to the theory of electromagnetism. The resulting equations are then used for a comparison of gravitational redshift in optical vortices with that of normal electromagnetic waves. We show that rotating bodies creating weak gravitational fields result in a magnitude of gravitational redshift in optical vortices that differs from the magnitude of gravitational redshift in flat light waves. We conclude our paper with a numerical analysis of the feasibility of detecting the discrepancy in gravitational redshift between optical vortices and flat waves in the gravitational fields of the Earth and the Sun.

Electromagnetic Ion Cyclotron Waves in the Helium Branch Induced by Multiple Electromagnetic Ion Cyclotron Triggered Emissions

NASA Astrophysics Data System (ADS)

Shoji, M.; Omura, Y.; Grison, B.; Pickett, J. S.; Dandouras, I. S.; Engebretson, M. J.

2011-12-01

Electromagnetic ion cyclotron (EMIC) triggered emissions with rising tones between the H+ and He+ cyclotron frequencies were found in the inner magnetosphere by the recent Cluster observations. Another type of EMIC wave with a constant frequency is occasionally observed below the He+ cyclotron frequency after the multiple EMIC triggered emissions. We performed a self-consistent hybrid simulation with a one-dimensional cylindrical magnetic flux model approximating the dipole magnetic field of the Earth's inner magnetosphere. In the presence of energetic protons with a sufficient density and temperature anisotropy, multiple EMIC triggered emissions are reproduced due to the nonlinear wave growth mechanism of rising-tone chorus emissions, and a constant frequency wave in the He+ EMIC branch is subsequently generated. Through interaction with the multiple EMIC rising-tone emissions, the velocity distribution function of the energetic protons is strongly modified. Because of the pitch angle scattering of the protons, the gradient of the distribution in velocity phase space is enhanced along the diffusion curve of the He+ branch wave, resulting in the linear growth of the EMIC wave in the He+ branch.

Electromagnetic ion cyclotron waves in the helium branch induced by multiple electromagnetic ion cyclotron triggered emissions

NASA Astrophysics Data System (ADS)

Shoji, Masafumi; Omura, Yoshiharu; Grison, Benjamin; Pickett, Jolene; Dandouras, Iannis; Engebretson, Mark

2011-09-01

Electromagnetic ion cyclotron (EMIC) triggered emissions with rising tones between the H+ and He+ cyclotron frequencies were found in the inner magnetosphere by the recent Cluster observations. Another type of EMIC wave with a constant frequency is occasionally observed below the He+ cyclotron frequency after the multiple EMIC triggered emissions. We performed a self-consistent hybrid simulation with a one-dimensional cylindrical magnetic flux model approximating the dipole magnetic field of the Earth's inner magnetosphere. In the presence of energetic protons with a sufficient density and temperature anisotropy, multiple EMIC triggered emissions are reproduced due to the nonlinear wave growth mechanism of rising-tone chorus emissions, and a constant frequency wave in the He+ EMIC branch is subsequently generated. Through interaction with the multiple EMIC rising-tone emissions, the velocity distribution function of the energetic protons is strongly modified. Because of the pitch angle scattering of the protons, the gradient of the distribution in velocity phase space is enhanced along the diffusion curve of the He+ branch wave, resulting in the linear growth of the EMIC wave in the He+ branch.

Design/cost tradeoff studies. Earth Observatory Satellite system definition study (EOS)

NASA Technical Reports Server (NTRS)

1974-01-01

The results of design/cost tradeoff studies conducted during the Earth Observatory Satellite system definition studies are presented. The studies are concerned with the definition of a basic modular spacecraft capable of supporting a variety of operational and/or research and development missions, with the deployment either by conventional launch vehicles or by means of the space shuttle. The three levels investigated during the study are: (1) subsystem tradeoffs, (2) spacecraft tradeoffs, and (3) system tradeoffs. The range of requirements which the modular concept must span is discussed. The mechanical, thermal, power, data and electromagnetic compatibility aspects of modularity are analyzed. Other data are provided for the observatory design concept, the payloads, integration and test, the ground support equipment, and ground data management systems.

A review of ISEAS design

NASA Technical Reports Server (NTRS)

Bykat, Alex

1993-01-01

The Space Station Freedom will offer facilities for experimentation and testing not available and not feasible or possible on earth. Due to a restricted space availability on board, the experimentation equipment and its organization will be frequently changing. This requires careful attention to electromagnetic compatibility between experimentation and other SSF equipment. To analyze the interactions between different equipment modules, a software system ISEAS is under development. Development of ISEAS was approached in two phases. In the 1st phase a PC version prototype of ISEAS was developed. In the 2nd phase, the PC prototype will be adapted to a VAX range of computers. The purpose of this paper is to review the design of the VAX version of ISEAS, and to recommend any suitable changes.

The Italian contribution to the CSES satellite

NASA Astrophysics Data System (ADS)

Conti, Livio

2016-04-01

We present the Italian contribution to the CSES (China Seismo-Electromagnetic Satellite) mission. The CSES satellite aims at investigating electromagnetic field, plasma and particles in the near-Earth environment in order to study in particular seismic precursors, particles fluxes (from Van Allen belts, cosmic rays, solar wind, etc.), anthropogenic electromagnetic pollution and more in general the atmosphere-ionosphere-magnetosphere coupling mechanisms that can affect the climate changes. The launch of CSES - the first of a series of several satellite missions - is scheduled by the end of 2016. The CSES satellite has been financed by the CNSA (China National Space Agency) and developed by CEA (China Earthquake Administration) together with several Chinese research institutes and private companies such as the DFH (that has developed the CAST2000 satellite platform). Italy participates to the CSES satellite mission with the LIMADOU project funded by ASI (Italian Space Agency) in collaboration with the Universities of Roma Tor Vergata, Uninettuno, Trento, Bologna and Perugia, as well as the INFN (Italian National Institute of Nuclear Physics), INGV (Italian National Institute of Geophysics and Volcanology) and INAF-IAPS (Italian National Institute of Astrophysics and Planetology). Many analyses have shown that satellite observations of electromagnetic fields, plasma parameters and particle fluxes in low Earth orbit may be useful in order to study the existence of electromagnetic emissions associated with the occurrence of earthquakes of medium and high magnitude. Although the earthquakes forecasting is not possible today, it is certainly a major challenge - and perhaps even a duty - for science in the near future. The claims that the reported anomalies (of electromagnetic, plasma and particle parameters) are seismic precursors are still intensely debated and analyses for confirming claimed correlations are still lacking. In fact, ionospheric currents, plasma parameters and stability of Van Allen belt are constantly modified by natural non-seismic and man-made processes. Therefore, in order to identify seismo-associated perturbations, it is needed to reject the "normal" background effects of the e.m. emissions due to: geomagnetic storms, tropospheric phenomena, and artificial sources (such as power lines, VLF transmitters, HF stations, etc.). Currently, the only available large database is that collected by the Demeter satellite and by rare observations made by some previous space missions, non-dedicated to this purpose. The CSES satellite aims at continuing the exploration started by Demeter with advanced multi-parametric measurements. The configuration of the CSES sensors foresees measurements of energetic particle fluxes, ionospheric plasma parameters and electromagnetic fields, in a wide range of energy and frequencies. The main sensors onboard the satellite are: the HEPD (High Energy Particle Detector) developed by the Italian participants, and the following Chinese sensors: LEPD (Low Energy Particle Detector), LP (Langmuir Probes), IDM (Ion Drift Meter), ICM (Ion Capture Meter), RPA (Retarding Potential Analyzer), EFD (Electric Field Detectors) developed in collaboration with Italian team, HPM (High Precision Magnetometer) and SCM (Search-Coil Magnetometer). The research activity is at an advanced phase, being the various payloads already built and, right now, an intense activity is going on for calibration of the various sensors. In particular, the Italian payload HEPD is under test at the laboratories of the National Institute for Nuclear Physics (INFN) and the Chinese payloads LP, IDM, ICM, RPA and EFD are tested at the INAF-IAPS "Plasma Chamber" in Rome, which is a facility where the response of the sensors, and their compatibility with ionospheric plasma, can be verified in environmental conditions very similar to those met by the satellite in orbit.

Predicting electromagnetic ion cyclotron wave amplitude from unstable ring current plasma conditions

DOE PAGES

Fu, Xiangrong; Cowee, Misa M.; Jordanova, Vania K.; ...

2016-11-01

Electromagnetic ion cyclotron (EMIC) waves in the Earth's inner magnetosphere are enhanced fluctuations driven unstable by ring current ion temperature anisotropy. EMIC waves can resonate with relativistic electrons and play an important role in precipitation of MeV radiation belt electrons. In this study, we investigate the excitation and saturation of EMIC instability in a homogeneous plasma using both linear theory and nonlinear hybrid simulations. We have explored a four-dimensional parameter space, carried out a large number of simulations, and derived a scaling formula that relates the saturation EMIC wave amplitude to initial plasma conditions. Finally, such scaling can be usedmore » in conjunction with ring current models like ring current-atmosphere interactions model with self-consistent magnetic field to provide global dynamic EMIC wave maps that will be more accurate inputs for radiation belt modeling than statistical models.« less

Micro-satellites (~ 50 kg) for the fundamental and applied science. Capacity building for Russian Academy of Sciences

NASA Astrophysics Data System (ADS)

Zelenyi, Lev; Rodin, V.; Gurevich, A.; Alferov, A.; Getsov, P.

Design and manufacturing of micro-satellite ( 50 kg) platforms for the fundamental and applied research of the Earth and near-earth outer space is a problem which is complex both scientifically and technically. Main point is to define the scientific task which could be effectively solved by micro-satellite instrumentation. It is necessary also to carry out an integral approach in the course of the spacecraft development: find methods to introduce the contemporary technological-design, use the achievements of advanced physical instrument manufacturing , microelectronics and micromechanics. Technical solutions should provide the required accuracy of spacecraft orientation and stabilization. Space Research and Physical Institutes RAS with participation of Moscow University developed the model composition and technical design of micro satellite "CHIBIS" (small bird LAPWING in Russian) with two options for scientific payload: A. The complex of scientific instruments N1 for the monitoring of Global warming and the electromagnetic environment of the Earth: spectrometer for measurements of the total content of greenhouse gases (CO2 and CH4); optical camera (spatial resolution 300 m); lowfrequency flux-gate magnetometer (DC - 64 Hz); high-frequency search-coil magnetometer (0.1 - 40 kHz); analyzer of the electromagnetic emissions (0.1 - 40 kHz); detector of ionospheric plasma. B. The complex of scientific instruments N2 for investigation of fine scale physics of lightning discharges: X-ray - gamma detector (range of X-ray and gamma emission - 50-500 keV); UV detector (range UV - emission - 300-450 nm); radiofrequency analyzer (20 - 50 MHz); optical camera. Spacecraft manufacturing and scientific experiments are prepared mostly by the institutes of Russian academy of sciences without traditional involvement of large scale space industry. So this activity serves as a substantial driver of Academic capacity building for the independent research of space science problems. Further extension of this program is planned now to be within the framework of collaboration between Russian and Bulgarian Academies of Sciences on "BalkanSat" project. Recently ((3/7 -09-2007) special international workshop on the Use of Micro-Satellite Technologies for Environmental Monitoring and Impact to Human Health was held by United Nations, IKI , RAS and ESA in the small city TARUSA near Moscow. Proceedings are available at http://www.iki.rssi.ru/ This work was partially supported of the RFBR grants 06-02-08076 and 06-02-08244

Nonlinear Generation of Electromagnetic Waves through Induced Scattering by Thermal Plasma.

PubMed

Tejero, E M; Crabtree, C; Blackwell, D D; Amatucci, W E; Mithaiwala, M; Ganguli, G; Rudakov, L

2015-12-09

We demonstrate the conversion of electrostatic pump waves into electromagnetic waves through nonlinear induced scattering by thermal particles in a laboratory plasma. Electrostatic waves in the whistler branch are launched that propagate near the resonance cone. When the amplitude exceeds a threshold ~5 × 10(-6) times the background magnetic field, wave power is scattered below the pump frequency with wave normal angles (~59°), where the scattered wavelength reaches the limits of the plasma column. The scattered wave has a perpendicular wavelength that is an order of magnitude larger than the pump wave and longer than the electron skin depth. The amplitude threshold, scattered frequency spectrum, and scattered wave normal angles are in good agreement with theory. The results may affect the analysis and interpretation of space observations and lead to a comprehensive understanding of the nature of the Earth's plasma environment.

Terahertz technology and applications

NASA Technical Reports Server (NTRS)

Siegel, P.

2002-01-01

Despite great scientific interest since at least the 1920's, the THz frequency range remains on e of the least tapped regions of the electromagnetic spectrum. Sandwiched between traditional microwave and optical technologies where there is a limited atmospheric propagation path, little commercial emphasis has been placed on THz systems. This has, perhaps fortunately, preserved some unique science and applications for tomorrow's technologies. For over 25 years the sole niche for THz technology has been in the high resolution spectroscopy and remote sensing areas where heterodyne and Fourier transform techniques have allowed astronomers, chemists, Earth, planetary and space scientists to measure, catalog and map thermal emission lines for a wide variety of lightweight molecules. As it turns out, no where else in the electromagnetic spectrum do we receive so much information about these chemical species. In fact, the universe is bathed in THz energy, most of it going unnoticed and undetected.

CubeSats in Hydrology: Ultrahigh-Resolution Insights Into Vegetation Dynamics and Terrestrial Evaporation

NASA Astrophysics Data System (ADS)

McCabe, M. F.; Aragon, B.; Houborg, R.; Mascaro, J.

2017-12-01

Satellite-based remote sensing has generally necessitated a trade-off between spatial resolution and temporal frequency, affecting the capacity to observe fast hydrological processes and rapidly changing land surface conditions. An avenue for overcoming these spatiotemporal restrictions is the concept of using constellations of satellites, as opposed to the mission focus exemplified by the more conventional space-agency approach to earth observation. Referred to as CubeSats, these platforms offer the potential to provide new insights into a range of earth system variables and processes. Their emergence heralds a paradigm shift from single-sensor launches to an operational approach that envisions tens to hundreds of small, lightweight, and comparatively inexpensive satellites placed into a range of low earth orbits. Although current systems are largely limited to sensing in the optical portion of the electromagnetic spectrum, we demonstrate the opportunity and potential that CubeSats present the hydrological community via the retrieval of vegetation dynamics and terrestrial evaporation and foreshadow future sensing capabilities.

Cryosphere: a kingdom of anomalies and diversity

NASA Astrophysics Data System (ADS)

Melnikov, Vladimir; Gennadinik, Viktor; Kulmala, Markku; Lappalainen, Hanna K.; Petäjä, Tuukka; Zilitinkevich, Sergej

2018-05-01

The cryosphere of the Earth overlaps with the atmosphere, hydrosphere and lithosphere over vast areas with temperatures below 0 °C and pronounced H2O phase changes. In spite of its strong variability in space and time, the cryosphere plays the role of a global thermostat, keeping the thermal regime on the Earth within rather narrow limits, affording continuation of the conditions needed for the maintenance of life. Objects and processes related to cryosphere are very diverse, due to the following basic reasons: the anomalous thermodynamic and electromagnetic properties of H2O, the intermediate intensity of hydrogen bonds and the wide spread of cryogenic systems all over the Earth. However, these features attract insufficient attention from research communities. Cryology is usually understood as a descriptive discipline within physical geography, limited to glaciology and permafrost research. We emphasise its broad interdisciplinary landscape involving physical, chemical and biological phenomena related to the H2O phase transitions and various forms of ice. This paper aims to draw the attention of readers to the crucial importance of cryogenic anomalies, which make the Earth atmosphere and the entire Earth system very special, if not unique, objects in the universe.

Electromagnetic absorption properties of spacecraft and space debris

NASA Astrophysics Data System (ADS)

Micheli, D.; Santoni, F.; Giusti, A.; Delfini, A.; Pastore, R.; Vricella, A.; Albano, M.; Arena, L.; Piergentili, F.; Marchetti, M.

2017-04-01

Aim of the work is to present a method to evaluate the electromagnetic absorption properties of spacecraft and space debris. For these objects, the radar detection ability depends mainly on volume, shape, materials type and other electromagnetic reflecting behaviour of spacecraft surface components, such as antennas or thermal blankets, and of metallic components in space debris. The higher the electromagnetic reflection coefficient of such parts, the greater the radar detection possibility. In this research an electromagnetic reverberation chamber is used to measure the absorption cross section (ACS) of four objects which may represent space structure operating components as well as examples of space debris: a small satellite, a composite antenna dish, a Thermal Protection System (TPS) tile and a carbon-based composite missile shell. The ACS mainly depends on geometrical characteristics like apertures, face numbers and bulk porosity, as well as on the type of the material itself. The ACS, which is an electromagnetic measurement, is expressed in squared meters and thus can be compared with the objects geometrical cross section. A small ACS means a quite electromagnetic reflective tendency, which is beneficial for radar observations; on the contrary, high values of ACS indicate a strong absorption of the electromagnetic field, which in turn can result a critical hindering of radar tracking.

E-CANES: A Research Network dedicated to Electromagnetic Coupling of the Atmosphere With Near-Earth Space

NASA Astrophysics Data System (ADS)

Hanuise, C.; Blanc, E.; Crosby, N.; Ebert, U.; Mareev, E.; Neubert, T.; Rothkaehl, H.; Santolik, O.; Yair, Y.; Gille, P.

2008-12-01

Transient luminous events in the stratosphere and mesosphere, the sprites, elves, blue jets and gigantic jets, are observed above intense thunderstorms in association with particularly intense lightning discharges. Their recent discovery (1989) offers an opportunity to study the fundamental process of the electric discharge under the different conditions of the troposphere (lightning), stratosphere (blue jets) and the mesosphere (sprites) and the coupling between these regions by electric and magnetic fields. It further facilitates studies of the more general questions of thunderstorm effects on the atmosphere and the role of thunderstorms in a changing climate. New space missions will be launched in the coming years to study the various effects of thunderstorms. They will focus on transient luminous events, the generation of relativistic electron beams in discharges, and the perturbation to the atmosphere, ionosphere and magnetosphere of lightning, transient luminous events, water vapour transport and gravity waves. The missions are the French micro-satellite TARANIS, the ESA ASIM payload on board the International Space Station and the Japanese Sprite Sat mission. These highly interdisciplinary missions will result in a wealth of new data, which require knowledge based capacity building to underpin the observations with improved statistical data analysis and theoretical modelling. We are therefore establishing a global framework for research on thunderstorm processes and their effect on the atmosphere, in particular (1) the fundamental process of the electric discharge as manifested in the stratosphere and mesosphere as sprites and jets, (2) the relationship between cosmic rays, lightning discharges, transient luminous events and terrestrial gamma ray flashes, and (3) the environmental impact of the above physical processes, and thunderstorms in general, on the atmosphere and near-Earth space. The first step has been the creation of the European research group (GDRE) dubbed E-CANES (Electromagnetic Coupling of the Atmosphere with the Near-Earth Space). It complements in a synergistic way the former EU Research Training Network 'Coupling of Atmospheric Layers', the existing COST action on 'The physics of lightning flash and its effects', the ASIM Topical Team, and other programs. The main objective of E-CANES is to initiate and promote coordination activities towards a global research community on the subject. The first actions include the establishment of an organization for coordinating ground, balloon and aircraft observation campaigns, the creation of a community-wide mailing list and website, and the promotion and coordination of joint activities with other structures - to include new communities and to avoid the duplication of meetings and workshops.

New Results About the Earth’s Van Allen Radiation Belts

NASA Astrophysics Data System (ADS)

Baker, Daniel

2015-01-01

The first great scientific discovery of the Space Age was that the Earth is enshrouded in toroids, or 'belts', of very high-energy magnetically trapped charged particles. Early observations of the radiation environment clearly indicated that the Van Allen belts could be delineated into an inner zone dominated by high-energy protons and an outer zone dominated by high-energy electrons. Subsequent studies showed that electrons in the energy range 100 keV < E< 1 MeV often populated both the inner and outer zones with a pronounced 'slot' region relatively devoid of energetic electrons existing between them. This two-belt structure for the Van Allen moderate-energy electron component was explained as being due to strong interactions of electrons with electromagnetic waves just inside the cold plasma (plasmapause) boundary. The energy distribution, spatial extent and particle species makeup of the Van Allen belts has been subsequently explored by several space missions. However, recent observations by the NASA dual-spacecraft Van Allen Probes mission have revealed wholly unexpected properties of the radiation belts, especially at highly relativistic (E > 2 MeV) and ultra-relativistic (E > 5 MeV) kinetic energies. In this presentation we show using high spatial and temporal resolution data from the Relativistic Electron-Proton Telescope (REPT) experiment on board the Van Allen Probes that multiple belts can exist concurrently and that an exceedingly sharp inner boundary exists for ultra-relativistic electrons. Using additionally available Van Allen Probes data, we demonstrate that these remarkable features of energetic electrons are not due to a physical boundary within Earth's intrinsic magnetic field. Neither is it likely that human-generated electromagnetic transmitter wave fields might produce such effects. Rather, we conclude from these unique measurements that slow natural inward radial diffusion combined with weak, but persistent, wave-particle pitch angle scattering deep inside the Earth's magnetosphere can conspire to create an almost impenetrable barrier through which the most energetic Van Allen belt electrons cannot migrate.

RBSPICE in the Classroom: Building a ballistic galvanometer using common household products

NASA Astrophysics Data System (ADS)

Patterson, J. D.; Manweiler, J. W.; Lanzerotti, L. J.; Zwiener, H.

2016-12-01

"RBSPICE in the Classroom: Changing Magnetic Fields and Electrical Currents" is a hands-on exercise for middle school and high school science classrooms. Students build a ballistic galvanometer using inexpensive common items that can be purchased at any craft store, and make qualitative observations of changing magnetic fields and the electrical currents they create. The goal of this work is to provide teachers new materials to use in their classrooms as tools for teaching students about electricity and magnetism. The experiment relates our Earth as a planet to the role the Magnetosphere plays in protecting us from Space Weather. The experiments show the ways in which Van Allen Probes play an important part in exploring those relationships using such instruments as the Radiation Belt Storm Probes Ion Composition Experiment (RBSPICE). The exercise is a vehicle for discussing electromagnetic induction, the behavior of the Earth's magnetosphere coupled with storm-time conditions that produce the Earth's ring current, and the mission objectives of the Van Allen Probes RBSPICE instrument.

Simulation of electromagnetic ion cyclotron triggered emissions in the Earth's inner magnetosphere

NASA Astrophysics Data System (ADS)

Shoji, Masafumi; Omura, Yoshiharu

2011-05-01

In a recent observation by the Cluster spacecraft, emissions triggered by electromagnetic ion cyclotron (EMIC) waves were discovered in the inner magnetosphere. We perform hybrid simulations to reproduce the EMIC triggered emissions. We develop a self-consistent one-dimensional hybrid code with a cylindrical geometry of the background magnetic field. We assume a parabolic magnetic field to model the dipole magnetic field in the equatorial region of the inner magnetosphere. Triggering EMIC waves are driven by a left-handed polarized external current assumed at the magnetic equator in the simulation model. Cold proton, helium, and oxygen ions, which form branches of the dispersion relation of the EMIC waves, are uniformly distributed in the simulation space. Energetic protons with a loss cone distribution function are also assumed as resonant particles. We reproduce rising tone emissions in the simulation space, finding a good agreement with the nonlinear wave growth theory. In the energetic proton velocity distribution we find formation of a proton hole, which is assumed in the nonlinear wave growth theory. A substantial amount of the energetic protons are scattered into the loss cone, while some of the resonant protons are accelerated to higher pitch angles, forming a pancake velocity distribution.

Subgrid geoelectric field specification for GIC modeling

NASA Astrophysics Data System (ADS)

Butala, M.; Grawe, M.; Kamalabadi, F.; Makela, J. J.

2017-12-01

Geomagnetically induced currents (GICs) result from surface geomagnetic field (ěc{B}) variation driven by space weather disturbances. For the most intense disturbances, the consequences can range from power grid instability to even widespread failure. Modeling GICs to assess vulnerability requires the specification of the surface geoelectric field (ěc{E}) at all spatial locations coincident with the electric power system. In this study, we investigate how to best reproduce ěc{E} given the available sparse, irregularly spaced magnetometer measurements of ěc{B} and suitable electromagnetic transfer functions (EMTFs) to transform the local ěc{B} to ěc{E}. The assessment is made against ground truth from publicly available ěc{E} measurements provided by the EarthScope magnetotelluric (MT) array, a set of 7 fixed and several transportable joint ěc{B} and ěc{E} sensors. The scope of this study spans several dimensions: geomagnetic disturbance intensity, spatial interpolation scheme, and EMTF type, i.e., 1-D models based on studies of local geology and 3-D models derived from the EarthScope MT data.

Effects of Sm addition on electromagnetic interference shielding property of Mg-Zn-Zr alloys

NASA Astrophysics Data System (ADS)

Yang, Chubin; Pan, Fusheng; Chen, Xianhua; Luo, Ning

2017-06-01

The electromagnetic interference (EMI) shielding of Sm-containing magnesium alloys in the 30-1500 MHz testing frequency range was investigated by coaxial cable method. The results demonstrated that Mg-3Zn alloys displayed the best electromagnetic shielding property. When 0.5 wt% of Zr was added for crystal grain refinement, the shielding effectiveness (SE) was apparently reduced. The addition of the rare earth element Sm in ZK magnesium alloys can improve the electromagnetic interference shielding of magnesium alloys. The main reason for the differences in electromagnetic interference shielding of magnesium alloys was the change in conductivity. The addition of Zr in Mg-Zn alloys can refine the grains and consequently improve the grain boundary area significantly. Therefore, the number of irregularly arranged atoms at the grain boundaries increased, decreasing the conductivity of magnesium alloys and leading to a decrease in the electromagnetic interference shielding. Following the Sm addition, the Mg-Zn-Sm phase was precipitated at the grain boundaries and in cores. The precipitation of Sm-containing rare earth phases could consume the solid-soluted Zn atoms within the Mg, resulting in an increase in electrical conductivity and electromagnetic interference shielding improvement.

Active and passive electromagnetic sounding on comets and moons

NASA Astrophysics Data System (ADS)

Przyklenk, Anita; Auster, Hans-Ulrich

We want to present the method of electromagnetic sounding on small extraterrestrial bodies to determine interior structures of those. Our sensors are perfectly suited for rover or lander missions, because they do not weight much (sum of all devices is approximately 600g) and can be easily installed at the bottom of a rover or at lander feet. The aim is to measure the material-specific complex resistivity, which depends on the electrical resistivity and electrical permittivity, for various sounding depth. This penetration depth depends on the 2 different operating modes. In the active mode, that is the so called Capacitive Resistivity (CR) method, the sounding depth is around a few meters. The CR is a purely electrical field measurement and works with a 4 electrode array. 2 of them are transmitter electrodes. They inject AC signals with frequencies between 100 Hz and 100 kHz into the subsurface. Then 2 receiver electrodes pick up the generated potentials. And a 4-point impedance can be calculated that depends on the electrical parameters among others [Grard, 1990a and b] [Kuras, 2002]. The second operating mode is the passive one. In the so called magneto telluric method the penetration depth depends on electrical parameters and can be in range of several 100m to km. Here, for excitation natural magnetic field variations are used. The magnetic field components are measured with our Fluxgate Magnetometer (FGM) (flight heritage: Rosetta, Venus Express, Themis,…). Induced electrical field components are measured again with the CR electrode array. Then the electromagnetic impedance can be derived, which depends on electrical resistivity among others. In the end, we want to discuss advantages and disadvantages of investigations during space missions compared to surveys on earth. As examples we have a closer look at the jovian moon Ganymede, the earth moon and the comet 67P/Churyumov-Gerasimenko and consider the applicability of electromagnetic sounding on this objects from a theoretical point of view.

Developement of a Fluxgate Magnetometer for the KITSAT-3 Satellite

NASA Astrophysics Data System (ADS)

Hwang, S. H.; Lee, D. H.; Min, K. W.; Shin, Y. H.; Choi, C. R.; Nobuhito, O.

1997-12-01

The magnetometer is one of the most important payloads of scientific satellites to monitor the near-earth space environment. The electromagnetic variations of the space environment can be observed with the electric and magnetic field measurements. In practice, it is well known that the measurement of magnetic fields needs less technical complexities than that of electric fields in space. Therefore the magnetometer has long been recognized as one of the basic payloads for the scientific satellites. In this paper, we discuss the scientific fluxgate magnetometer which will be on board the KITSAT-3. The main circuit design of the present magnetometer is based on that of KISAT-1 and -2 but its facilities have been re-designed to improve the resolution to about 5nT for scientific purpose. The calibration and noise level test of this circuit have been performed at the laboratory of the Tierra Tecnica company in Japan.

Estimating the power-law distribution of Earth electrical conductivity from low-frequency, controlled-source electromagnetic responses

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

Beskardes, G. D.; Weiss, Chester J.; Everett, M. E.

Electromagnetic responses reflect the interaction between applied electromagnetic fields and heterogeneous geoelectrical structures. Here by quantifying the relationship between multi-scale electrical properties and the observed electromagnetic response is therefore important for meaningful geologic interpretation. Furthermore, we present here examples of near-surface electromagnetic responses whose spatial fluctuations appear on all length scales, are repeatable and fractally distributed, suggesting that the spatial fluctuations may be considered as “geologic noise”.

Estimating the power-law distribution of Earth electrical conductivity from low-frequency, controlled-source electromagnetic responses

DOE PAGES

Beskardes, G. D.; Weiss, Chester J.; Everett, M. E.

2016-11-30

Electromagnetic responses reflect the interaction between applied electromagnetic fields and heterogeneous geoelectrical structures. Here by quantifying the relationship between multi-scale electrical properties and the observed electromagnetic response is therefore important for meaningful geologic interpretation. Furthermore, we present here examples of near-surface electromagnetic responses whose spatial fluctuations appear on all length scales, are repeatable and fractally distributed, suggesting that the spatial fluctuations may be considered as “geologic noise”.

Parametric excitation of very low frequency (VLF) electromagnetic whistler waves and interaction with energetic electrons in radiation belt

NASA Astrophysics Data System (ADS)

Sotnikov, V.; Kim, T.; Caplinger, J.; Main, D.; Mishin, E.; Gershenzon, N.; Genoni, T.; Paraschiv, I.; Rose, D.

2018-04-01

The concept of a parametric antenna in ionospheric plasma is analyzed. Such antennas are capable of exciting electromagnetic radiation fields, specifically the creation of whistler waves generated at the very low frequency (VLF) range, which are also capable of propagating large distances away from the source region. The mechanism of whistler wave generation is considered a parametric interaction of quasi-electrostatic whistler waves (also known as low oblique resonance (LOR) oscillations) excited by a conventional loop antenna. The interaction of LOR waves with quasi-neutral density perturbations in the near field of an antenna gives rise to electromagnetic whistler waves on combination frequencies. It is shown in this work that the amplitude of these waves can considerably exceed the amplitude of whistler waves directly excited by a loop. Additionally, particle-in-cell simulations, which demonstrate the excitation and spatial structure of VLF waves excited by a loop antenna, are presented. Possible applications including the wave-particle interactions to mitigate performance anomalies of low Earth orbit satellites, active space experiments, communication via VLF waves, and modification experiments in the ionosphere will be discussed.

ISEE observations of low frequency waves and ion distribution function evolution in the plasma sheet boundary layer

NASA Technical Reports Server (NTRS)

Elphic, R. C.; Gary, S. P.

1990-01-01

This paper describes ISEE plasma and magnetic fluctuation observations during two crossings of the plasma sheet boundary layer (PSBL) in the earth's magnetotail. Distribution function observations show that the counterstreaming ion components undergo pitch-angle scattering and evolve into a shell distribution in velocity space. This evolution is correlated with the development of low frequency, low amplitude magnetic fluctuations. However, the measured wave amplitudes are insufficient to accomplish the observed degree of ion pitch-angle scatttering locally; the near-earth distributions may be the result of processes occurring much farther down the magnetotail. Results show a clear correlation between the ion component beta and the relative streaming speed of the two components, suggesting that electromagnetic ion/ion instabilities do play an important role in the scattering of PSBL ions.

Comparison of eigenvectors for coupled seismo-electromagnetic layered-Earth modelling

NASA Astrophysics Data System (ADS)

Grobbe, N.; Slob, E. C.; Thorbecke, J. W.

2016-07-01

We study the accuracy and numerical stability of three eigenvector sets for modelling the coupled poroelastic and electromagnetic layered-Earth response. We use a known eigenvector set, its flux-normalized version and a newly derived flux-normalized set. The new set is chosen such that the system is properly uncoupled when the coupling between the poroelastic and electromagnetic fields vanishes. We carry out two different numerical stability tests: the first test focuses on the internal system, eigenvector and eigenvalue consistency; the second test investigates the stability and preciseness of the flux-normalized systems by looking at identity relations. We find that the known set shows the largest deviation for both tests, whereas the new set performs best. In two additional numerical modelling experiments, these numerical inaccuracies are shown to generate numerical noise levels comparable to small signals, such as signals coming from the important interface conversion responses, especially when the coupling coefficient is small. When coupling vanishes completely, the known set does not produce proper results. The new set produces numerically stable and accurate results in all situations. We therefore strongly recommend to use this newly derived set for future layered-Earth seismo-electromagnetic modelling experiments.

Surface biosignatures of exo-earths: remote detection of extraterrestrial life.

PubMed

Hegde, Siddharth; Paulino-Lima, Ivan G; Kent, Ryan; Kaltenegger, Lisa; Rothschild, Lynn

2015-03-31

Exoplanet discovery has made remarkable progress, with the first rocky planets having been detected in the central star's liquid water habitable zone. The remote sensing techniques used to characterize such planets for potential habitability and life rely solely on our understanding of life on Earth. The vegetation red edge from terrestrial land plants is often used as a direct signature of life, but it occupies only a small niche in the environmental parameter space that binds life on present-day Earth and has been widespread for only about 460 My. To more fully exploit the diversity of the one example of life known, we measured the spectral characteristics of 137 microorganisms containing a range of pigments, including ones isolated from Earth's most extreme environments. Our database covers the visible and near-infrared to the short-wavelength infrared (0.35-2.5 µm) portions of the electromagnetic spectrum and is made freely available from biosignatures.astro.cornell.edu. Our results show how the reflectance properties are dominated by the absorption of light by pigments in the visible portion and by strong absorptions by the cellular water of hydration in the infrared (up to 2.5 µm) portion of the spectrum. Our spectral library provides a broader and more realistic guide based on Earth life for the search for surface features of extraterrestrial life. The library, when used as inputs for modeling disk-integrated spectra of exoplanets, in preparation for the next generation of space- and ground-based instruments, will increase the chances of detecting life.

Method for imaging with low frequency electromagnetic fields

DOEpatents

Lee, Ki H.; Xie, Gan Q.

1994-01-01

A method for imaging with low frequency electromagnetic fields, and for interpreting the electromagnetic data using ray tomography, in order to determine the earth conductivity with high accuracy and resolution. The imaging method includes the steps of placing one or more transmitters, at various positions in a plurality of transmitter holes, and placing a plurality of receivers in a plurality of receiver holes. The transmitters generate electromagnetic signals which diffuse through a medium, such as earth, toward the receivers. The measured diffusion field data H is then transformed into wavefield data U. The traveltimes corresponding to the wavefield data U, are then obtained, by charting the wavefield data U, using a different regularization parameter .alpha. for each transform. The desired property of the medium, such as conductivity, is then derived from the velocity, which in turn is constructed from the wavefield data U using ray tomography.

Method for imaging with low frequency electromagnetic fields

DOEpatents

Lee, K.H.; Xie, G.Q.

1994-12-13

A method is described for imaging with low frequency electromagnetic fields, and for interpreting the electromagnetic data using ray tomography, in order to determine the earth conductivity with high accuracy and resolution. The imaging method includes the steps of placing one or more transmitters, at various positions in a plurality of transmitter holes, and placing a plurality of receivers in a plurality of receiver holes. The transmitters generate electromagnetic signals which diffuse through a medium, such as earth, toward the receivers. The measured diffusion field data H is then transformed into wavefield data U. The travel times corresponding to the wavefield data U, are then obtained, by charting the wavefield data U, using a different regularization parameter [alpha] for each transform. The desired property of the medium, such as conductivity, is then derived from the velocity, which in turn is constructed from the wavefield data U using ray tomography. 13 figures.

Antenna Measurements: Test & Analysis of the Radiated Emissions from the NASA/Orion Spacecraft - Parachute System Simulator

NASA Technical Reports Server (NTRS)

Norgard, John D.

2012-01-01

For future NASA Manned Space Exploration of the Moon and Mars, a blunt body capsule, called the Orion Crew Exploration Vehicle (CEV), composed of a Crew Module (CM) and a Service Module (SM), with a parachute decent assembly is planned for reentry back to Earth. A Capsule Parachute Assembly System (CPAS) is being developed for preliminary parachute drop tests at the Yuma Proving Ground (YPG) to simulate high-speed reentry to Earth from beyond Low-Earth-Orbit (LEO) and to provide measurements of landing parameters and parachute loads. The avionics systems on CPAS also provide mission critical firing events to deploy, reef, and release the parachutes in three stages (extraction, drogues, mains) using mortars and pressure cartridge assemblies. In addition, a Mid-Air Delivery System (MDS) is used to separate the capsule from the sled that is used to eject the capsule from the back of the drop plane. Also, high-speed and high-definition cameras in a Video Camera System (VCS) are used to film the drop plane extraction and parachute landing events. To verify Electromagnetic Compatibility (EMC) of the CPAS system from unintentional radiation, Electromagnetic Interference (EMI) measurements are being made inside a semi-anechoic chamber at NASA/JSC at 1m from the electronic components of the CPAS system. In addition, EMI measurements of the integrated CPAS system are being made inside a hanger at YPG. These near-field B-Dot probe measurements on the surface of a parachute simulator (DART) are being extrapolated outward to the 1m standard distance for comparison to the MIL-STD radiated emissions limit.

Electromagnetic deep-probing (100-1000 KMS) of the Earth's interior from artificial satellites: Constraints on the regional emplacement of crustal resources

NASA Technical Reports Server (NTRS)

Hermance, J. F. (Principal Investigator)

1981-01-01

An algorithm was developed to address the problem of electromagnetic coupling of ionospheric current systems to both a homogeneous Earth having finite conductivity, and to an Earth having gross lateral variations in its conductivity structure, e.g., the ocean-land interface. Typical results from the model simulation for ionospheric currents flowing parallel to a representative geologic discontinuity are shown. Although the total magnetic field component at the satellite altitude is an order of magnitude smaller than at the Earth's surface (because of cancellation effects from the source current), the anomalous behavior of the satellite observations as the vehicle passes over the geologic contact is relatively more important pronounced. The results discriminate among gross lithospheric structures because of difference in electrical conductivity.

Atomic Oxygen Task

NASA Technical Reports Server (NTRS)

Hadaway, James B.

1997-01-01

This report details work performed by the Center for Applied Optics (CAO) at the University of Alabama in Huntsville (UAH) on the contract entitled 'Atomic Oxygen Task' for NASA's Marshall Space Flight Center (contract NAS8-38609, Delivery Order 109, modification number 1). Atomic oxygen effects on exposed materials remain a critical concern in designing spacecraft to withstand exposure in the Low Earth Orbit (LEO) environment. The basic objective of atomic oxygen research in NASA's Materials & Processes (M&P) Laboratory is to provide the solutions to material problems facing present and future space missions. The objective of this work was to provide the necessary research for the design of specialized experimental test configurations and development of techniques for evaluating in-situ space environmental effects, including the effects of atomic oxygen and electromagnetic radiation on candidate materials. Specific tasks were performed to address materials issues concerning accelerated environmental testing as well as specifically addressing materials issues of particular concern for LDEF analysis and Space Station materials selection.

Numerical simulation of electromagnetic waves in Schwarzschild space-time by finite difference time domain method and Green function method

NASA Astrophysics Data System (ADS)

Jia, Shouqing; La, Dongsheng; Ma, Xuelian

2018-04-01

The finite difference time domain (FDTD) algorithm and Green function algorithm are implemented into the numerical simulation of electromagnetic waves in Schwarzschild space-time. FDTD method in curved space-time is developed by filling the flat space-time with an equivalent medium. Green function in curved space-time is obtained by solving transport equations. Simulation results validate both the FDTD code and Green function code. The methods developed in this paper offer a tool to solve electromagnetic scattering problems.

Interaction dynamics of high Reynolds number magnetized plasma flow on the CTIX plasma accelerator

NASA Astrophysics Data System (ADS)

Howard, Stephen James

The Compact Toroid Injection eXperiment, (CTIX), is a coaxial railgun that forms and accelerates magnetized plasma rings called compact toroids (CT's). CTIX consists of a pair of cylindrical coaxial electrodes with the region between them kept at high vacuum (2 m long, 15 cm outer diameter). Hydrogen is typically the dominant constituent of the CT plasma, however helium can also be used. The railgun effect that accelerates the CT can be accounted for by the Lorentz j x B force density created by the power input from a capacitor bank of roughly a Giga-Watt peak. The final velocity of the CT can be as high as 300 km/s, with an acceleration of about 3 billion times Earth's gravity. The compact toroid is able to withstand these forces because of a large internal magnetic field of about 1 Tesla. Understanding the nature of high speed flow of a magnetized plasma has been the primary challenge of this work. In this dissertation we will explore a sequence of fundamental questions regarding the plasma physics of CTIX. First we will go over some new results about the structure and dynamics of the compact toroid's magnetic field, and its electrical resistivity. Then we will present the results from a sequence of key experiments involving reconnection/compression and thermalization of the plasma during interaction of the CT with target magnetic fields of various geometries. Next, we look at the Doppler shift of a spectral line of the He II ion as a measurement of plasma velocity, and to gain insight into the ionization physics of helium in our plasma. These preliminary experiments provide the background for our primary experimental tool for investigating turbulence, a technique called Gas Puff Imaging (GPI) in which a cloud of helium can be used to enhance plasma brightness, allowing plasma density fluctuations to be imaged. We will conclude with an analysis of the images that show coherent density waves, as well as the transition to turbulence during the interaction with a wire target perturbation.

Protecting the Power Grid From Electromagnetic Pulses

NASA Astrophysics Data System (ADS)

Simpson, Sarah

2004-10-01

A nuclear explosion high in the Earth's atmosphere does no immediate known harm to living things, but the resulting electromagnetic pulse (EMP) from a single detonation could degrade 70 percent or more of the country's electrical service in an instant, warns the Commission to Assess the Threat to the United States from Electromagnetic Pulse Attack, which presented its findings to the U.S. Congress in July.

Sliding mode control of electromagnetic tethered satellite formation

NASA Astrophysics Data System (ADS)

Hallaj, Mohammad Amin Alandi; Assadian, Nima

2016-08-01

This paper investigates the control of tethered satellite formation actuated by electromagnetic dipoles and reaction wheels using the robust sliding mode control technique. Generating electromagnetic forces and moments by electric current coils provides an attractive control actuation alternative for tethered satellite system due to the advantages of no propellant consumption and no obligatory rotational motion. Based on a dumbbell model of tethered satellite in which the flexibility and mass of the tether is neglected, the equations of motion in Cartesian coordinate are derived. In this model, the J2 perturbation is taken into account. The far-field and mid-field models of electromagnetic forces and moments of two satellites on each other and the effect of the Earth's magnetic field are presented. A robust sliding mode controller is designed for precise trajectory tracking purposes and to deal with the electromagnetic force and moment uncertainties and external disturbances due to the Earth's gravitational and magnetic fields inaccuracy. Numerical simulation results are presented to validate the effectiveness of the developed controller and its superiority over the linear controller.

Electromagnetic radiation generated by arcing in low density plasma

NASA Technical Reports Server (NTRS)

Vayner, Boris V.; Ferguson, Dale C.; Snyder, David B.; Doreswamy, C. V.

1996-01-01

An unavoidable step in the process of space exploration is to use high-power, very large spacecraft launched into Earth orbit. Obviously, the spacecraft will need powerful energy sources. Previous experience has shown that electrical discharges occur on the surfaces of a high-voltage array, and these discharges (arcs) are undesirable in many respects. Moreover, any high voltage conductor will interact with the surrounding plasma, and that interaction may result in electrical discharges between the conductor and plasma (or between two conductors with different potentials, for example, during docking and extravehicular activity). One very important aspect is the generation of electromagnetic radiation by arcing. To prevent the negative influence of electromagnetic noise on the operation of spacecraft systems, it seems necessary to determine the spectra and absolute levels of the radiation, and to determine limitations on the solar array bias voltage that depend on the parameters of LEO plasma and the technical requirements of the spacecraft equipment. This report describes the results of an experimental study and computer simulation of the electromagnetic radiation generated by arcing on spacecraft surfaces. A large set of high quality data was obtained during the Solar Array Module Plasma Interaction Experiment (SAMPIE, flight STS-62) and ground test. These data include the amplitudes of current, pulse forms, duration of each arc, and spectra of plasma waves. A theoretical explanation of the observed features is presented in this report too. The elaborated model allows us to determine the parameters of the electromagnetic noise for different frequency ranges, distances from the arcing site, and distinct kinds of plasma waves.

Schizophrenia: Do Sense Perceptions Correlate with Episodic Activity, as Indians Know Kokopelli/Pele Matches with Mother Earth's Electromagnetic Field Activity, EMF?

NASA Astrophysics Data System (ADS)

McCulley, Aspen; Pawa Matagamon, Sagamo; McLeod, David Matthew

2007-10-01

Certain Indian cognomens seem to indicate an environmental awareness of an electromagnetic wrath some traditional cultures are careful to acknowledge and accommodate. These include Pele/Kokopelli, Keitan, and Hobomock, that have carried explicit information our cultures have been cognizant of Mother Earth's not-always-benign influences. Let's consider schizophrenia, with or without a viral cofactor, and Kokopelli/Pele. She/he may be explicitly referenced as a hunch-backed, flute-playing individual, dancing-around in correlation with Earth's electromagnetic activities. Depending on the specific version and its details, individuals, particularly children, are admonished to avoid certain areas. Of especial importance and relevance may be cultural awareness that individuals, whom another type of culture has discriminated against, despite no a priori guilt, are explicitly absolved of culpability by the blanket statement that The Great Spirit is implicated in their behavior. Of course, this provides information of a religious sort, possibly corroborated by a currently prominent individual.

Electromagnetic deep-probing (100-1000 kms) of the Earth's interior from artificial satellites: Constraints on the regional emplacement of crustal resources

NASA Technical Reports Server (NTRS)

Hermance, J. F. (Principal Investigator)

1981-01-01

Efforts continue in the development of a computer program for looking at the coupling of finite dimensioned source fields with a laterally heterogeneous Earth. An algorithm for calculating a time-varying reference field using ground-based magnetic observatory data is also under development as part of the production of noise-free estimates of global electromagnetic response functions using Magsat data.

Electromagnetic Safety of Spacecraft During Active Experiments with the Use of Plasma Accelerators and Ion Injectors

NASA Astrophysics Data System (ADS)

Plokhikh, Andrey; Popov, Garri; Shishkin, Gennady; Antropov, Nikolay; Vazhenin, Nikolay; Soganova, Galina

Works under the development and application of stationary and pulsed plasma accelerators of charged particles conducted at the Moscow Aviation Institute and Research Institute of Applied Mechanics and Electrodynamics during over 40 years, active experiments on board meteorological rockets, artificial Earth satellites and "Mir" orbital station including [1], allowed to obtain data on the influence of pulsed and continuous plasma injection with the given parameters on the drop of energetic particles out of the radiation belts, efficiency of artificial excitation and propagation of electromagnetic waves in ELF and VLF ranges, and evolution of artificial plasma formations in different regions of ionosphere. Variation of the near-spacecraft electromagnetic environment related to the operation of plasma injectors was registered during active experiments along with the global electrodynamic processes. The measured electromagnetic fields are of rather high intensity and occupy frequency spectrum from some Hz to tens of GHz that may be of definite danger for the operation of spacecraft and its onboard systems. Analysis for the known test data is presented in the paper and methods are discussed for the diagnostics and modeling under laboratory conditions of radiative processes proceeding at the operation of plasma accelerators and ion injectors used while making active space experiments. Great attention is paid to the methodological and metrological bases for making radio measurements in vacuum chambers, design concept and hardware configuration of ground special-purpose instrumentation scientific complexes [2]. Basic requirements are formulated for the measurements and analysis of electromagnetic fields originating during the operation of plasma accelerators, including the radiative induced and conductive components inside the spacecraft, as well as the wave emission and excitation outside the spacecraft, in the ionosphere including. Measurement results for the intrinsic electromagnetic emission of stationary and pulsed plasma injectors and of the electric propulsions developed on their basis are discussed. Predictive estimates are presented for the influence of originating electromagnetic fields and emissions on the electromagnetic safety of spacecraft and its systems and for the reliability of communication with ground command and tracking stations, and recommendations are given on the reduction of destructive effects. 1. S. Avdyushin, I. Podgorny, G. Popov, A. Porotnikov, "Plasma Accelerator Use for Studying Physical Processes in Space." Plasma Accelerators and Ion Injectors, Nauka, 1984. 2. A. Plokhikh, "Peculiarities of Radio Measurements in the Metal Vacuum Chambers." Vestnik moskovskogo aviatsionnogo instituta. v. 11, No. 2, 2004, pp. 66-78.

On coincident loop transient electromagnetic induction logging

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

Swidinsky, Andrei; Weiss, Chester J.

Coincident loop transient induction wireline logging is examined as the borehole analog of the well-known land and airborne time-domain electromagnetic (EM) method. The concept of whole-space late-time apparent resistivity is modified from the half-space version commonly used in land and airborne geophysics and applied to the coincident loop voltages produced from various formation, borehole, and invasion models. Given typical tool diameters, off-time measurements with such an instrument must be made on the order of nanoseconds to microseconds — much more rapidly than for surface methods. Departure curves of the apparent resistivity for thin beds, calculated using an algorithm developed tomore » model the transient response of a loop in a multilayered earth, indicate that the depth of investigation scales with the bed thickness. Modeled resistivity logs are comparable in accuracy and resolution with standard frequency-domain focused induction logs. However, if measurement times are longer than a few microseconds, the thicknesses of conductors can be overestimated, whereas resistors are underestimated. Thin-bed resolution characteristics are explained by visualizing snapshots of the EM fields in the formation, where a conductor traps the electric field while two current maxima are produced in the shoulder beds surrounding a resistor. Radial profiling is studied using a concentric cylinder earth model. Results found that true formation resistivity can be determined in the presence of either oil- or water-based mud, although in the latter case, measurements must be taken several orders of magnitude later in time. Lastly, the ability to determine true formation resistivity is governed by the degree that the EM field heals after being distorted by borehole fluid and invasion, a process visualized and particularly evident in the case of conductive water-based mud.« less

On coincident loop transient electromagnetic induction logging

DOE PAGES

Swidinsky, Andrei; Weiss, Chester J.

2017-05-31

Coincident loop transient induction wireline logging is examined as the borehole analog of the well-known land and airborne time-domain electromagnetic (EM) method. The concept of whole-space late-time apparent resistivity is modified from the half-space version commonly used in land and airborne geophysics and applied to the coincident loop voltages produced from various formation, borehole, and invasion models. Given typical tool diameters, off-time measurements with such an instrument must be made on the order of nanoseconds to microseconds — much more rapidly than for surface methods. Departure curves of the apparent resistivity for thin beds, calculated using an algorithm developed tomore » model the transient response of a loop in a multilayered earth, indicate that the depth of investigation scales with the bed thickness. Modeled resistivity logs are comparable in accuracy and resolution with standard frequency-domain focused induction logs. However, if measurement times are longer than a few microseconds, the thicknesses of conductors can be overestimated, whereas resistors are underestimated. Thin-bed resolution characteristics are explained by visualizing snapshots of the EM fields in the formation, where a conductor traps the electric field while two current maxima are produced in the shoulder beds surrounding a resistor. Radial profiling is studied using a concentric cylinder earth model. Results found that true formation resistivity can be determined in the presence of either oil- or water-based mud, although in the latter case, measurements must be taken several orders of magnitude later in time. Lastly, the ability to determine true formation resistivity is governed by the degree that the EM field heals after being distorted by borehole fluid and invasion, a process visualized and particularly evident in the case of conductive water-based mud.« less

Sun-to-Earth Analysis of a Major Geoeffective Solar Eruption within the Framework of the

NASA Astrophysics Data System (ADS)

Patsourakos, S.; Vlahos, L.; Georgoulis, M.; Tziotziou, K.; Nindos, A.; Podladchikova, O.; Vourlidas, A.; Anastasiadis, A.; Sandberg, I.; Tsinganos, K.; Daglis, I.; Hillaris, A.; Preka-Papadema, P.; Sarris, M.; Sarris, T.

2013-09-01

Transient expulsions of gigantic clouds of solar coronal plasma into the interplanetary space in the form of Coronal Mass Ejections (CMEs) and sudden, intense flashes of electromagnetic radiation, solar flares, are well-established drivers of the variable Space Weather. Given the innate, intricate links and connections between the solar drivers and their geomagnetic effects, synergistic efforts assembling all pieces of the puzzle along the Sun-Earth line are required to advance our understanding of the physics of Space Weather. This is precisely the focal point of the Hellenic National Space Weather Research Network (HNSWRN) under the THALIS Programme. Within the HNSWRN framework, we present here the first results from a coordinated multi-instrument case study of a major solar eruption (X5.4 and X1.3 flares associated with two ultra-fast (>2000 km/s) CMEs) which were launched early on 7 March 2012 and triggered an intense geomagnetic storm (min Dst =-147 nT) approximately two days afterwards. Several elements of the associated phenomena, such as the flare and CME, EUV wave, WL shock, proton and electron event, interplanetary type II radio burst, ICME and magnetic cloud and their spatiotemporal relationships and connections are studied all way from Sun to Earth. To this end, we make use of satellite data from a flotilla of solar, heliospheric and magnetospheric missions and monitors (e.g., SDO, STEREO, WIND, ACE, Herschel, Planck and INTEGRAL). We also present our first steps toward formulating a cohesive physical scenario to explain the string of the observables and to assess the various physical mechanisms than enabled and gave rise to the significant geoeffectiveness of the eruption.

Planetary benchmarks. [structural design criteria for radar reference devices on planetary surfaces

NASA Technical Reports Server (NTRS)

Uphoff, C.; Staehle, R.; Kobrick, M.; Jurgens, R.; Price, H.; Slade, M.; Sonnabend, D.

1978-01-01

Design criteria and technology requirements for a system of radar reference devices to be fixed to the surfaces of the inner planets are discussed. Offshoot applications include the use of radar corner reflectors as landing beacons on the planetary surfaces and some deep space applications that may yield a greatly enhanced knowledge of the gravitational and electromagnetic structure of the solar system. Passive retroreflectors with dimensions of about 4 meters and weighing about 10 kg are feasible for use with orbiting radar at Venus and Mars. Earth-based observation of passive reflectors, however, would require very large and complex structures to be delivered to the surfaces. For Earth-based measurements, surface transponders offer a distinct advantage in accuracy over passive reflectors. A conceptual design for a high temperature transponder is presented. The design appears feasible for the Venus surface using existing electronics and power components.

Discrimination between preseismic electromagnetic anomalies and solar activity effects

NASA Astrophysics Data System (ADS)

Koulouras, Gr; Balasis, G.; Kontakos, K.; Ruzhin, Y.; Avgoustis, G.; Kavouras, D.; Nomicos, C.

2009-04-01

Laboratory studies suggest that electromagnetic emissions in a wide frequency spectrum ranging from kHz to very high MHz frequencies are produced by the opening of microcracks, with the MHz radiation appearing earlier than the kHz radiation. Earthquakes are large-scale fracture phenomena in the Earth's heterogeneous crust. Thus, the radiated kHz-MHz electromagnetic emissions are detectable not only at laboratory but also at geological scale. Clear MHz-to-kHz electromagnetic anomalies have been systematically detected over periods ranging from a few days to a few hours prior to recent destructive earthquakes in Greece. We bear in mind that whether electromagnetic precursors to earthquakes exist is an important question not only for earthquake prediction but mainly for understanding the physical processes of earthquake generation. An open question in this field of research is the classification of a detected electromagnetic anomaly as a pre-seismic signal associated to earthquake occurrence. Indeed, electromagnetic fluctuations in the frequency range of MHz are known to related to a few sources, i.e., they might be atmospheric noise (due to lightning), man-made composite noise, solar-terrestrial noise (resulting from the Sun-solar wind-magnetosphere-ionosphere-Earth's surface chain) or cosmic noise, and finally, lithospheric effect, namely pre-seismic activity. We focus on this point. We suggest that if a combination of detected kHz and MHz electromagnetic anomalies satisfies the herein presented set of criteria these anomalies could be considered as candidate precursory phenomena of an impending earthquake.

Discrimination between pre-seismic electromagnetic anomalies and solar activity effects

NASA Astrophysics Data System (ADS)

Koulouras, G.; Balasis, G.; Kiourktsidis, I.; Nannos, E.; Kontakos, K.; Stonham, J.; Ruzhin, Y.; Eftaxias, K.; Cavouras, D.; Nomicos, C.

2009-04-01

Laboratory studies suggest that electromagnetic emissions in a wide frequency spectrum ranging from kilohertz (kHz) to very high megahertz (MHz) frequencies are produced by the opening of microcracks, with the MHz radiation appearing earlier than the kHz radiation. Earthquakes are large-scale fracture phenomena in the Earth's heterogeneous crust. Thus, the radiated kHz-MHz electromagnetic emissions are detectable not only in the laboratory but also at a geological scale. Clear MHz-to-kHz electromagnetic anomalies have been systematically detected over periods ranging from a few days to a few hours prior to recent destructive earthquakes in Greece. We should bear in mind that whether electromagnetic precursors to earthquakes exist is an important question not only for earthquake prediction but mainly for understanding the physical processes of earthquake generation. An open question in this field of research is the classification of a detected electromagnetic anomaly as a pre-seismic signal associated with earthquake occurrence. Indeed, electromagnetic fluctuations in the frequency range of MHz are known to be related to a few sources, including atmospheric noise (due to lightning), man-made composite noise, solar-terrestrial noise (resulting from the Sun-solar wind-magnetosphere-ionosphere-Earth's surface chain) or cosmic noise, and finally, the lithospheric effect, namely pre-seismic activity. We focus on this point in this paper. We suggest that if a combination of detected kHz and MHz electromagnetic anomalies satisfies the set of criteria presented herein, these anomalies could be considered as candidate precursory phenomena of an impending earthquake.

Electromagnetic earthquake triggering phenomena: State-of-the-art research and future developments

NASA Astrophysics Data System (ADS)

Zeigarnik, Vladimir; Novikov, Victor

2014-05-01

Developed in the 70s of the last century in Russia unique pulsed power systems based on solid propellant magneto-hydrodynamic (MHD) generators with an output of 10-500 MW and operation duration of 10 to 15 s were applied for an active electromagnetic monitoring of the Earth's crust to explore its deep structure, oil and gas electrical prospecting, and geophysical studies for earthquake prediction due to their high specific power parameters, portability, and a capability of operation under harsh climatic conditions. The most interesting and promising results were obtained during geophysical experiments at the test sites located at Pamir and Northern Tien Shan mountains, when after 1.5-2.5 kA electric current injection into the Earth crust through an 4 km-length emitting dipole the regional seismicity variations were observed (increase of number of weak earthquakes within a week). Laboratory experiments performed by different teams of the Institute of Physics of the Earth, Joint Institute for High Temperatures, and Research Station of Russian Academy of Sciences on observation of acoustic emission behavior of stressed rock samples during their processing by electric pulses demonstrated similar patterns - a burst of acoustic emission (formation of cracks) after application of current pulse to the sample. Based on the field and laboratory studies it was supposed that a new kind of earthquake triggering - electromagnetic initiation of weak seismic events has been observed, which may be used for the man-made electromagnetic safe release of accumulated tectonic stresses and, consequently, for earthquake hazard mitigation. For verification of this hypothesis some additional field experiments were carried out at the Bishkek geodynamic proving ground with application of pulsed ERGU-600 facility, which provides 600 A electric current in the emitting dipole. An analysis of spatio-temporal redistribution of weak regional seismicity after ERGU-600 pulses, as well as a response of geoacoustic emission recorded in the wells at a distance of 7-12 km from the emitting dipole to the ERGU-600 pulses confirmed the effects of an influence of electromagnetic field on the deformation processes in the Earth crust and the real existence of electromagnetic triggering phenomena. For verification of results of field observations laboratory studies of behavior of rock samples under critical stress-strain state and external electric actions were carried out at the spring and lever presses, as well as at the stick-slip models simulated the seismic cycle (stress accumulation and discharge) in the seismogenic geological fault. Various possible mechanisms of weak electrical stimulation (electric current density 10-7-10-8 mA/cm2 at a depth of earthquake epicenters of 5 to10 km) of deformation processes in the Earth crust, including increased fluid pore pressure, electrokinetic phenomena, magnetostriction, electrical stimulation of fluid migration into the fault area are considered. However, the mechanism of electromagnetic earthquake triggering phenomena is still open. Based on the field observations of electromagnetic triggering of weak seismicity resulting in a partial safe release of stresses in the Earth crust a possibility of control of seismic process is considered for risk reduction of catastrophic earthquakes. The results obtained from field and laboratory experiments on electromagnetic initiation of seismic events allow to consider a problem of lithosphere-ionosphere relations from another point of view. Keeping in mind that the current density generated in the Earth crust by artificial electric source is comparable with the density of telluric currents induced during severe ionospheric disturbances (e.g., magnetic storms) it may be possible under certain favorable conditions in lithosphere to initiate earthquakes by electromagnetic disturbances in ionosphere. A possibility of application of these triggering phenomena for short-term earthquake prediction is discussed.

Space Science

NASA Image and Video Library

1992-09-01

This photograph of aurora borealis, northern aurora, was taken during the Spacelab-J (SL-J) mission (STS-47). People who live in the northernmost areas like Alaska or work in the southernmost regions like Antarctica often see colorful lights produced by Earth's natural electromagnetic generator; these shimmering expanses of light are auroras, commonly called the northern and southern lights. Charged particles from the magnetosphere follow magnetic fields and are accelerated toward Earth at the magnetic poles where they strike molecules in the upper atmosphere, staining the sky with the red and green lights of oxygen and hydrogen, and the purples and pinks of nitrogen. The altitude and inclination of the Spacelab will give scientists unique views of auroras, which occur at altitudes ranging from about 90 to 300 kilometers (56 to 186 miles). Most views of the auroras have been from the ground where only limited parts can be seen. These Spacelab views will give scientists information on their complex structure and chemical composition. The Spacelab-J was a joint mission of NASA and the National Space Development Agency of Japan (NASDA) utilizing a marned Spacelab module. The mission conducted microgravity investigations in materials and life sciences. The SL-J was launched aboard the Space Shuttle Orbiter Endeavour (STS-47) on September 12, 1992.

Space Science

NASA Image and Video Library

1992-09-01

This photograph of aurora borealis, northern aurora, was taken during the Spacelab-J (SL-J) mission (STS-47). People who live in the northernmost areas like Alaska or work in the southernmost regions like Antarctica often see colorful lights produced by Earth's natural electromagnetic generator; these shimmering expanses of light are auroras, commonly called the northern and southern lights. Charged particles from the magnetosphere follow magnetic fields and are accelerated toward Earth at the magnetic poles where they strike molecules in the upper atmosphere, staining the sky with the red and green lights of oxygen and hydrogen, and the purples and pinks of nitrogen. The altitude and inclination of the Spacelab will give scientists unique views of auroras, which occur at altitudes ranging from about 90 to 300 kilometers (56 to 186 miles). Most views of the auroras have been from the ground where only limited parts can be seen. These Skylab views will give scientists information on their complex structure and chemical composition. The Spacelab-J was a joint mission of NASA and the National Space Development Agency of Japan (NASDA) utilizing a marned Spacelab module. The mission conducted microgravity investigations in materials and life sciences. The SL-J was launched aboard the Space Shuttle Orbiter Endeavour (STS-47) on September 12, 1992.

Design of a lunar propellant processing facility. NASA/USRA advanced program

NASA Technical Reports Server (NTRS)

Batra, Rajesh; Bell, Jason; Campbell, J. Matt; Cash, Tom; Collins, John; Dailey, Brian; France, Angelique; Gareau, Will; Gleckler, Mark; Hamilton, Charles

1993-01-01

Mankind's exploration of space will eventually lead to the establishment of a permanent human presence on the Moon. Essential to the economic viability of such an undertaking will be prudent utilization of indigenous lunar resources. The design of a lunar propellant processing system is presented. The system elements include facilities for ore processing, ice transportation, water splitting, propellant storage, personnel and materials transportation, human habitation, power generation, and communications. The design scenario postulates that ice is present in the lunar polar regions, and that an initial lunar outpost was established. Mining, ore processing, and water transportation operations are located in the polar regions. Water processing and propellant storage facilities are positioned near the equator. A general description of design operations is outlined below. Regolith containing the ice is mined from permanently-shaded polar craters. Water is separated from the ore using a microwave processing technique, and refrozen into projectiles for launch to the equatorial site via railgun. A mass-catching device retrieves the ice. This ice is processed using fractional distillation to remove impurities, and the purified liquid water is fed to an electrolytic cell that splits the water into vaporous hydrogen and oxygen. The hydrogen and oxygen are condensed and stored separately in a tank farm. Electric power for all operations is supplied by SP-100 nuclear reactors. Transportation of materials and personnel is accomplished primarily using chemical rockets. Modular living habitats are used which provide flexibility for the placement and number of personnel. A communications system consisting of lunar surface terminals, a lunar relay satellite, and terrestrial surface stations provides capabilities for continuous Moon-Moon and Moon-Earth transmissions of voice, picture, and data.

3D modeling of lightning-induced electromagnetic pulses on Venus, Jupiter and Saturn

NASA Astrophysics Data System (ADS)

Pérez-Invernón, Francisco J.; Luque, Alejandro; Gordillo-Vázquez, Francisco J.

2017-04-01

Atmospheric electricity is a common phenomenon in some planets of The Solar System. We know that atmospheric discharges exist on Earth and gaseous planets; however, some characteristics of lightning on Saturn and Jupiter as well as their relevance on the effects of lightning in the atmospheres of these planets are still unknown. In the case of Venus, there exist some radio evidences of lightning, but the lack of optical observations suggests exploring indirect methods of detection, such as searching for lightning-induced transient optical emissions from the upper atmosphere. The Akatsuki probe, currently orbiting Venus, is equipped with a camera whose temporal resolution is high enough to detect optical emissions from lightning discharges and to measure nightglow enhancements. In this work, we extend previous models [1,2] to investigate the chemical impact and transient optical emissions produced by possible lightning-emitted electromagnetic pulses (EMP) in Venus, Saturn and Jupiter. Using a 3D FDTD ("Finite Differences Time Domain") model we solve the Maxwell equations coupled with the Langevin equation for electrons [3] and with a kinetic scheme, different for each planetary atmosphere. This method is useful to investigate the temporal and spatial impact of lightning-induced electromagnetic fields in the atmosphere of each planet for different lightning characteristics (e.g. energy released, orientation). This 3D FDTD model allows us to include the saturnian and jovian background magnetic field inclination and magnitude at different latitudes, and to determine the effects of different lightning channel inclinations. Results provide useful information to interpret lightning observations on giant gaseous planets and in the search for indirect optical signals from atmospheric discharge on Venus such as fast nightglow transient enhancements related to lightning as seen on Earth. Furthermore, we underline the observation of electrical discharges characteristics as a powerful tool to obtain information about planetary atmospheres, such as density profiles of electrons or other components. Our model may also be useful to extend some studies about the chemical impact of EMP pulses in the terrestrial atmosphere [4]. References [1] Luque, A., D. Dubrovin, F. J. Gordillo-Vázquez, U. Ebert, F. C. Parra-Rojas, Y. Yair, and C. Price (2014), Coupling between atmospheric layers in gaseous giant planets due to lightning-generated electromagnetic pulses, J. Geophys. Res. (Space Phys), 119, 8705, doi: 10.1002/2014JA020457. [2] Pérez-Invernón, F. J., A. Luque, and F. J. Gordillo-Vázquez (2016), Mesospheric optical signatures of possible lightning on Venus, J. Geophys. Res. (Space Phys), 121, 7026, doi: 10.1029/2016JA022886. [3] Lee, J. H., and D. K. Kalluri (1999), Three-dimensional FDTD simulation of electromagnetic wave transformation in a dynamic inhomogeneous magnetized plasma, IEEE Transactions on Antennas and Propagation, 47, 1146, doi:10.1109/8.785745. [4] Marshall, R. A., U. S. Inan, and V. S. Glukhov (2010), Elves and associated electron density changes due to cloud-to-ground and in-cloud lightning discharges, J. Geophys. Res. (Space Phys), 115, A00E17, doi:10.1029/2009JA014469.

Pathway and conversion of energy incident on auroral and sub-auroral ionosphere at substorm expansion onset

NASA Astrophysics Data System (ADS)

Ebihara, Y.; Tanaka, T.

2017-12-01

One explanation for SAPS/SAID is the poleward ionospheric electric field arising from a pair of Region 1 and Region 2 field-aligned currents (FACs). At substorm expansion onset, the FACs are intensified, resulting in intensification of energy incident on the auroral and sub-auroral ionosphere. Where does the energy comes from? Based on the results obtained by the global magnetohydrodynamics (MHD) simulation, we present energy flow and energy conversion associated with the Region 1 and Region 2 FACs that are intensified at the onset of substorm expansion. The cusp/mantle region transmits electromagnetic energy to almost the entire region of the magnetosphere. A part of electromagnetic energy is stored in the lobe in the growth phase. When reconnection takes place in the near-Earth tail region, the stored energy is released in addition to the continuously supplied one from the cusp/mantle dynamo. Two types of pathways of energy seem to be involved in the generation of the near-Earth dynamo that is associated with FACs at the expansion onset. The first type is related to the earthward fast flow in the plasma sheet. The electromagnetic energy coming from the lobe splits into the thermal energy and the kinetic energy. The kinetic energy is then converted to the thermal energy and the electromagnetic energy, in association of flow braking. The second type is that the plasma coming from the lobe goes into the inner magnetosphere directly. The electromagnetic energy is converted to the thermal energy, followed by the electromagnetic energy at off-equator. The near-Earth dynamo region seems to be embedded in the magnetospheric convection system. In this sense, the expansion onset may be regarded as a sudden, local intensification of the convection.

Experimental characterization of a transition from collisionless to collisional interaction between head-on-merging supersonic plasma jets

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

Moser, Auna L., E-mail: mosera@fusion.gat.com; Hsu, Scott C., E-mail: scotthsu@lanl.gov

We present results from experiments on the head-on merging of two supersonic plasma jets in an initially collisionless regime for the counter-streaming ions. The plasma jets are of either an argon/impurity or hydrogen/impurity mixture and are produced by pulsed-power-driven railguns. Based on time- and space-resolved fast-imaging, multi-chord interferometry, and survey-spectroscopy measurements of the overlapping region between the merging jets, we observe that the jets initially interpenetrate, consistent with calculated inter-jet ion collision lengths, which are long. As the jets interpenetrate, a rising mean-charge state causes a rapid decrease in the inter-jet ion collision length. Finally, the interaction becomes collisional andmore » the jets stagnate, eventually producing structures consistent with collisional shocks. These experimental observations can aid in the validation of plasma collisionality and ionization models for plasmas with complex equations of state.« less

An Analysis of EM Railgun Cross Section Designs

DTIC Science & Technology

2009-08-14

tube does not have to be cured in an autoclave afterwards. The fact that the resin in the prepreg is a thermoplastic rather than a thermoset is...decided that a chromium copper alloy would be used to take advantage of the electrical properties of copper while having a high strength material. The

Full-duplex optical communication system

NASA Technical Reports Server (NTRS)

Shay, Thomas M. (Inventor); Hazzard, David A. (Inventor); Horan, Stephen (Inventor); Payne, Jason A. (Inventor)

2004-01-01

A method of full-duplex electromagnetic communication wherein a pair of data modulation formats are selected for the forward and return data links respectively such that the forward data electro-magnetic beam serves as a carrier for the return data. A method of encoding optical information is used wherein right-hand and left-hand circular polarizations are assigned to optical information to represent binary states. An application for an earth to low earth orbit optical communications system is presented which implements the full-duplex communication and circular polarization keying modulation format.

Energy conversion at dipolarization fronts

NASA Astrophysics Data System (ADS)

Khotyaintsev, Yu. V.; Divin, A.; Vaivads, A.; André, M.; Markidis, S.

2017-02-01

We use multispacecraft observations by Cluster in the Earth's magnetotail and 3-D particle-in-cell simulations to investigate conversion of electromagnetic energy at the front of a fast plasma jet. We find that the major energy conversion is happening in the Earth (laboratory) frame, where the electromagnetic energy is being transferred from the electromagnetic field to particles. This process operates in a region with size of the order several ion inertial lengths across the jet front, and the primary contribution to E·j is coming from the motional electric field and the ion current. In the frame of the front we find fluctuating energy conversion with localized loads and generators at sub-ion scales which are primarily related to the lower hybrid drift instability excited at the front; however, these provide relatively small net energy conversion.

Observation of Schumann Resonances in the Earth's Ionosphere

NASA Technical Reports Server (NTRS)

Simoes, Fernando; Pfaff, Robert; Freudenreich, Henry

2011-01-01

The surface of the Earth and the lower edge of the ionosphere define a cavity in which electromagnetic waves propagate. When the cavity is excited by broadband electromagnetic sources, e.g., lightning, a resonant state can develop provided the average equatorial circumference is approximately equal to an integral number of wavelengths of the electromagnetic waves. This phenomenon, known as Schumann resonance, corresponds to electromagnetic oscillations of the surface-ionosphere cavity, and has been used extensively to investigate atmospheric electricity. Using measurements from the Communications/Navigation Outage Forecasting System (C/NOFS) satellite, we report, for the first time, Schumann resonance signatures detected well beyond the upper boundary of the cavity. These results offer new means for investigating atmospheric electricity, tropospheric-ionospheric coupling mechanisms related to lightning activity, and wave propagation in the ionosphere. The detection of Schumann resonances in the ionosphere calls for revisions to the existing models of extremely low frequency wave propagation in the surface-ionosphere cavity. Additionally, these measurements suggest new remote sensing capabilities for investigating atmospheric electricity at other planets.

Electromagnetic Compatibility for the Space Shuttle

NASA Technical Reports Server (NTRS)

Scully, Robert C.

2004-01-01

This slide presentation reviews the Space Shuttle electromagnetic compatibility (EMC). It includes an overview of the design of the shuttle with the areas that are of concern for the electromagnetic compatibility. It includes discussion of classical electromagnetic interference (EMI) and the work performed to control the electromagnetic interference. Another area of interest is electrostatic charging and the threat of electrostatic discharge and the attempts to reduce damage to the Shuttle from these possible hazards. The issue of electrical bonding is als reviewed. Lastly the presentation reviews the work performed to protect the shuttle from lightning, both in flight and on the ground.

Project Aryavarta: A Novel approach in Innovative and energy efficient space transportation systems

NASA Astrophysics Data System (ADS)

Ghadawala, Rushi; Chokshi, Poojan; Verma, Rajeev

With the advancement of technology, there is a growing interest about other planets and so it would be necessary to shift the scientific analysis activities from the earth's orbit to that of other planets. The main aim of project ARYAVARTA is to shift a satellite orbit from one planet to another with the help of an Unmanned Space Vehicle (USV). For example, to shift scientific activities economically to other planets, we need to change the orbit of the satellite from earth to that of the other planet instead of sending separate space probes, as that would entail comparatively much higher cost. A solar powered USV is one that will be having ion propulsion system along with solar propulsion system. The USV, placed in rocket boosters, will be externally launched like a space shuttle to enable it to go beyond the atmospheric limit of the earth with sufficient escape velocity. Xenon cylinders attached to the USV will provide ion propulsion for furthering the mission. The USV will then be attached to the satellite revolving in the orbit of the earth. The satellite which is attached to the USV will be de-orbited with the help of xenon engines, and will be shifted to another orbit of another planet/satellite. Electricity generated by solar panels, made from multicrystalline solar cells, of the USV will be stored in the USV to help the mission/operational requirements. With the help of multireflectors, the reflected solar rays will be re-concentrated to the solar panel and hence, power efficiency will increase more than twice. Solar-electromagnetic propulsion would make such a mission possible because an ion engine can run almost continuously and outperform any chemical rocket for such long flights. This project will help to achieve higher efficiency with great economy, and eliminate the need for sending extra space probes for any other mission. As xenon engine occupies lesser room than conventional engines, more compact instruments will emerge ahead resulting in the overall reduction of the size and mass of the spacecraft, and thereby further increasing efficiency of the spacecraft.

Electron-trapping polycrystalline materials with negative electron affinity.

PubMed

McKenna, Keith P; Shluger, Alexander L

2008-11-01

The trapping of electrons by grain boundaries in semiconducting and insulating materials is important for a wide range of physical problems, for example, relating to: electroceramic materials with applications as sensors, varistors and fuel cells, reliability issues for solar cell and semiconductor technologies and electromagnetic seismic phenomena in the Earth's crust. Surprisingly, considering their relevance for applications and abundance in the environment, there have been few experimental or theoretical studies of the electron trapping properties of grain boundaries in highly ionic materials such as the alkaline earth metal oxides and alkali halides. Here we demonstrate, by first-principles calculations on MgO, LiF and NaCl, a qualitatively new type of electron trapping at grain boundaries. This trapping is associated with the negative electron affinity of these materials and is unusual as the electron is confined in the empty space inside the dislocation cores.

Dark photons from the center of the Earth: Smoking-gun signals of dark matter

NASA Astrophysics Data System (ADS)

Feng, Jonathan L.; Smolinsky, Jordan; Tanedo, Philip

2016-01-01

Dark matter may be charged under dark electromagnetism with a dark photon that kinetically mixes with the Standard Model photon. In this framework, dark matter will collect at the center of the Earth and annihilate into dark photons, which may reach the surface of the Earth and decay into observable particles. We determine the resulting signal rates, including Sommerfeld enhancements, which play an important role in bringing the Earth's dark matter population to their maximal, equilibrium value. For dark matter masses mX˜100 GeV - 10 TeV , dark photon masses mA'˜MeV -GeV , and kinetic mixing parameters ɛ ˜1 0-9- 1 0-7 , the resulting electrons, muons, photons, and hadrons that point back to the center of the Earth are a smoking-gun signal of dark matter that may be detected by a variety of experiments, including neutrino telescopes, such as IceCube, and space-based cosmic ray detectors, such as Fermi-LAT and AMS. We determine the signal rates and characteristics and show that large and striking signals—such as parallel muon tracks—are possible in regions of the (mA',ɛ ) plane that are not probed by direct detection, accelerator experiments, or astrophysical observations.

Exploring the Birth and Evolution of the Universe: How Detectors Have Revolutionized Space Astronomy

NASA Technical Reports Server (NTRS)

Moseley, Samuel H.

2012-01-01

The past century has seen tremendous advances in the capability of instruments used for astronomical imaging and spectroscopy. Capabilities of instruments have expanded in many dimensions; the scale of telescopes has grown tremendously, the wavelengths used for astronomy have grown from visible light to the full electromagnetic spectrum, extending from gamma rays to low frequency radio waves. Additional advances have been enabled by the availability of space facilities, which eliminate the effects of the earths atmosphere and magnetosphere, and allow cooling of instruments to avoid instrumental thermal radiation. Even with all these advances, the increase in capability of detection systems has produced truly revolutionary improvements in capability. Today, I will describe the advances in astronomical detection from the photographic plates of the early 20th century to the giant high efficiency focal planes being developed for modern space and ground based astronomical instrument. I will review the demanding performance requirements set by space astronomy, and show how the detector community has risen to the challenge in producing high performance detectors for the Hubble Space Telescope, the Spitzer Space Telescope, and the James Webb Space Telescope, now under development.

Electromagnetic waves with frequencies near the local proton gyrofrequency: ISEE-3 1 AU observations

NASA Technical Reports Server (NTRS)

Tsurutani, Bruce T.; Arballo, John K.; Mok, John; Smith, Edward J.; Mason, Glenn M.; Tan, Lun C.

1994-01-01

Low Frequency (LF) electromagnetic waves with periods near the local proton gyrofrequency have been detected in interplanetary space by the magnetometer onboard International-Sun-Earth-Explorer-3 (ISEE-3). Transverse peak-to-peak amplitudes as large as delta vector B/absolute value of B approximately 0.4 have been noted with compressional components (Delta absolute value of B/absolute value of B) typically less than or = 0.1. Generally, the waves have even smaller amplitudes, or are not detectable within the solar wind turbulence. The waves are elliptically/linearly polarized and are often, but not always, found to propagate nearly along vector B(sub zero). Both right- and left-hand polarizations in the spacecraft-frame have been detected. The waves are observed during all orientations of the interplanetary magnetic field, with the Parker spiral orientation being the most common case. Because the waves are detected at and near the local proton cyclotron frequency, the generation mechanism must almost certainly be solar wind pickup of freshly created hydrogen ions. Possible sources for the hydrogen are the Earth's atmosphere, coronal mass ejections from the Sun, comets and interstellar neutral atoms. At this time it is not obvious which potential source is the correct one. Statistical tests employing over one year of ISEE-3 data will be done in the near future to eliminate/confirm some of these possibilities.

Laboratory plasma physics experiments using merging supersonic plasma jets

DOE PAGES

Hsu, S. C.; Moser, A. L.; Merritt, E. C.; ...

2015-04-01

We describe a laboratory plasma physics experiment at Los Alamos National Laboratory that uses two merging supersonic plasma jets formed and launched by pulsed-power-driven railguns. The jets can be formed using any atomic species or mixture available in a compressed-gas bottle and have the following nominal initial parameters at the railgun nozzle exit: n e ≈ n i ~ 10¹⁶ cm⁻³, T e ≈ T i ≈ 1.4 eV, V jet ≈ 30–100 km/s, mean chargemore » $$\\bar{Z}$$ ≈ 1, sonic Mach number M s ≡ V jet/C s > 10, jet diameter = 5 cm, and jet length ≈ 20 cm. Experiments to date have focused on the study of merging-jet dynamics and the shocks that form as a result of the interaction, in both collisional and collisionless regimes with respect to the inter-jet classical ion mean free path, and with and without an applied magnetic field. However, many other studies are also possible, as discussed in this paper.« less

Laboratory plasma physics experiments using merging supersonic plasma jets

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

Hsu, S. C.; Moser, A. L.; Merritt, E. C.

We describe a laboratory plasma physics experiment at Los Alamos National Laboratory that uses two merging supersonic plasma jets formed and launched by pulsed-power-driven railguns. The jets can be formed using any atomic species or mixture available in a compressed-gas bottle and have the following nominal initial parameters at the railgun nozzle exit: n e ≈ n i ~ 10¹⁶ cm⁻³, T e ≈ T i ≈ 1.4 eV, V jet ≈ 30–100 km/s, mean chargemore » $$\\bar{Z}$$ ≈ 1, sonic Mach number M s ≡ V jet/C s > 10, jet diameter = 5 cm, and jet length ≈ 20 cm. Experiments to date have focused on the study of merging-jet dynamics and the shocks that form as a result of the interaction, in both collisional and collisionless regimes with respect to the inter-jet classical ion mean free path, and with and without an applied magnetic field. However, many other studies are also possible, as discussed in this paper.« less

On the possible relations between solar activities and global seismicity in the solar cycle 20 to 23

NASA Astrophysics Data System (ADS)

Herdiwijaya, Dhani; Arif, Johan; Nurzaman, Muhamad Zamzam; Astuti, Isna Kusuma Dewi

2015-09-01

Solar activities consist of high energetic particle streams, electromagnetic radiation, magnetic and orbital gravitational forces. The well-know solar activity main indicator is the existence of sunspot which has mean variation in 11 years, named by solar cycle, allow for the above fluctuations. Solar activities are also related to the space weather affecting all planetary atmospheric variability, moreover to the Earth's climate variability. Large extreme space and geophysical events (high magnitude earthquakes, explosive volcanic eruptions, magnetic storms, etc.) are hazards for humankind, infrastructure, economies, technology and the activities of civilization. With a growing world population, and with modern reliance on delicate technological systems, human society is becoming increasingly vulnerable to natural hazardous events. The big question arises to the relation between solar forcing energy to the Earth's global seismic activities. Estimates are needed for the long term occurrence-rate probabilities of these extreme natural hazardous events. We studied connectivity from yearly seismic activities that refer to and sunspot number within the solar cycle 20 to 23 of year 1960 to 2013 (53 years). We found clear evidences that in general high magnitude earthquake events and their depth were related to the low solar activity.

Wave-Particle Interactions Associated with Nongyrotropic Distribution Functions: A Hybrid Simulation Study

NASA Technical Reports Server (NTRS)

Convery, P. D.; Schriver, D.; Ashour-Abdalla, M.; Richard, R. L.

2002-01-01

Nongyrotropic plasma distribution functions can be formed in regions of space where guiding center motion breaks down as a result of strongly curved and weak ambient magnetic fields. Such are the conditions near the current sheet in the Earth's middle and distant magnetotail, where observations of nongyrotropic ion distributions have been made. Here a systematic parameter study of nongyrotropic proton distributions using electromagnetic hybrid simulations is made. We model the observed nongyrotropic distributions by removing a number of arc length segments from a cold ring distribution and find significant differences with the results of simulations that initially have a gyrotropic ring distribution. Model nongyrotropic distributions with initially small perpendicular thermalization produce growing fluctuations that diffuse the ions into a stable Maxwellian-like distribution within a few proton gyro periods. The growing waves produced by nongyrotropic distributions are similar to the electromagnetic proton cyclotron waves produced by a gyrotropic proton ring distribution in that they propagate parallel to the background magnetic field and occur at frequencies on the order of the proton gyrofrequency, The maximum energy of the fluctuating magnetic field increases as the initial proton distribution is made more nongyrotropic, that is, more highly bunched in perpendicular velocity space. This increase can be as much as twice the energy produced in the gyrotropic case.

Turbulence Heating ObserveR - THOR: mission overview and payload summary

NASA Astrophysics Data System (ADS)

Escoubet, C.-Philippe; Voirin, Thomas; Wielders, Arno; Vaivads, Andris; Retino, Alessandro; Khotyaintsev, Yuri; Soucek, Jan; Valentini, Francesco; Chen, Chris; Fazakerley, Andrew; Lavraud, Benoit; Marcucci, Federica; Narita, Yasuhito; Vainio, Rami; Romstedt, Jens; Boudin, Nathalie; Junge, Axel; Osuna, Pedro; Walsh, Andrew

2017-04-01

The Turbulence Heating ObserveR (THOR) mission was selected as one of the three candidates, following the Call for Medium Class Missions M4 by the European Space Agency, with a launch planned in 2026. THOR is the first mission ever flown in space dedicated to plasma turbulence. THOR will lead to an understanding of the basic plasma heating and particle energization processes, of their effect on different plasma species and of their relative importance in different turbulent regimes. The THOR mission features one single spinning spacecraft, with the spin axis pointing toward the Sun, and 10 state-of-the-art scientific instruments, measuring electromagnetic fields and waves and electrons and ions at the highest spatial and temporal resolution ever achieved. THOR focuses on particular regions: pristine solar wind, Earth's bow shock and interplanetary shocks, and compressed solar wind regions downstream of shocks, that will be observed with three different orbits of 6 x 15 RE, 6 x 25 RE and 6 x 45 RE. These regions are selected because of their differing turbulent fluctuation characteristics, and reflect similar astrophysical environments. The THOR mission, the conceptual design of the spacecraft and a summary of the payload will be presented. Furthermore, driving requirements and their implications for the spacecraft like Electromagnetic Compatibility and cleanliness will be discussed.

Artist Concept of Galaxy Evolution Explorer

NASA Image and Video Library

2002-12-21

The Galaxy Evolution Explorer was launched on April 28, 2003. Its mission is to study the shape, brightness, size and distance of galaxies across 10 billion years of cosmic history. The 50-centimeter-diameter (19.7-inch) telescope onboard the Galaxy Evolution Explorer sweeps the skies in search of ultraviolet-light sources. Ultraviolet is light from the higher end of the electromagnetic spectrum, just above visible light in frequency, but below X-rays and gamma rays. While a small amount of ultraviolet penetrates Earth's atmosphere, causing sunburn, the Galaxy Evolution Explorer observes those ultraviolet frequencies that can only be seen from space. http://photojournal.jpl.nasa.gov/catalog/PIA04234

KSC-01PP1052

NASA Image and Video Library

2001-05-31

The first stage of the Geostationary Operational Environmental Satellite-M (GOES-M) Atlas II rocket arrives at Complex 36-A, Cape Canaveral Air Force Station. It will be raised and lifted up the gantry for mating with other stages. The last in the current series of advanced geostationary weather satellites in service, GOES-M has a new instrument not on earlier spacecraft, a Solar X-ray Imager that can be used in forecasting space weather, the effects of solar storms that create electromagnetic disturbances on earth that affect other satellites, communications and power grids. GOES-M is scheduled to launch from Launch Complex 36-A, Cape Canaveral Air Force Station July 15

Seismic imaging of the Sun's far hemisphere and its applications in space weather forecasting

NASA Astrophysics Data System (ADS)

Lindsey, Charles; Braun, Douglas

2017-06-01

The interior of the Sun is filled acoustic waves with periods of about 5 min. These waves, called "p modes," are understood to be excited by convection in a thin layer beneath the Sun's surface. The p modes cause seismic ripples, which we call "the solar oscillations." Helioseismic observatories use Doppler observations to map these oscillations, both spatially and temporally. The p modes propagate freely throughout the solar interior, reverberating between the near and far hemispheres. They also interact strongly with active regions at the surfaces of both hemispheres, carrying the signatures of said interactions with them. Computational analysis of the solar oscillations mapped in the Sun's near hemisphere, applying basic principles of wave optics to model the implied p modes propagating through the solar interior, gives us seismic maps of large active regions in the Sun's far hemisphere. These seismic maps are useful for space weather forecasting. For the past decade, NASA's twin STEREO spacecraft have given us full coverage of the Sun's far hemisphere in electromagnetic (EUV) radiation from the far side of Earth's orbit about the Sun. We are now approaching a decade during which the STEREO spacecraft will lose their farside vantage. There will occur significant periods from thence during which electromagnetic coverage of the Sun's far hemisphere will be incomplete or nil. Solar seismology will make it possible to continue our monitor of large active regions in the Sun's far hemisphere for the needs of space weather forecasters during these otherwise blind periods.

Seismic imaging of the Sun's far hemisphere and its applications in space weather forecasting.

PubMed

Lindsey, Charles; Braun, Douglas

2017-06-01

The interior of the Sun is filled acoustic waves with periods of about 5 min. These waves, called " p modes," are understood to be excited by convection in a thin layer beneath the Sun's surface. The p modes cause seismic ripples, which we call "the solar oscillations." Helioseismic observatories use Doppler observations to map these oscillations, both spatially and temporally. The p modes propagate freely throughout the solar interior, reverberating between the near and far hemispheres. They also interact strongly with active regions at the surfaces of both hemispheres, carrying the signatures of said interactions with them. Computational analysis of the solar oscillations mapped in the Sun's near hemisphere, applying basic principles of wave optics to model the implied p modes propagating through the solar interior, gives us seismic maps of large active regions in the Sun's far hemisphere. These seismic maps are useful for space weather forecasting. For the past decade, NASA's twin STEREO spacecraft have given us full coverage of the Sun's far hemisphere in electromagnetic (EUV) radiation from the far side of Earth's orbit about the Sun. We are now approaching a decade during which the STEREO spacecraft will lose their farside vantage. There will occur significant periods from thence during which electromagnetic coverage of the Sun's far hemisphere will be incomplete or nil. Solar seismology will make it possible to continue our monitor of large active regions in the Sun's far hemisphere for the needs of space weather forecasters during these otherwise blind periods.

Gravity Shifting Due to Distribution of Momentum in Black Hole and its Relation with Time Flux

NASA Astrophysics Data System (ADS)

Gholibeigian, Hassan; Gholibeygian, Mohammad Hossein

2017-04-01

There are many local convection systems of heat and mass in black holes. These large scale coupled systems including planets and molten masses which generate momentum in black hole and consequently generate coupled gravitational and electromagnetic waves. Therefore black hole's gravity is shifting due to distribution of masses/momentum in its convection systems. Two massive black holes which merged at a distance of 1.3 billion light years far from the Earth, produced different momentum and energy before, during, and after the event in different locations of the black hole. This energy and momentum produced gravitational waves which radiated away and recorded on September 14, 2015 by two detectors of the Laser Interferometry Gravitational Observatories (LIGO) in USA. On the other hand, the nature of time is wavy-like motion of the matter and nature of space is jerky-like motion of the matter. These two natures of space-time can be matched on wave-particle duality in quantum mechanics. And also magnitude of the time for an atom is momentum of its involved fundamental particles [Gholibeigian, adsabs.harvard.edu/abs/2016APS.APR.D1032G]. ∑ ⃗R(mv, σ,τ ) = (pnucleons + pelectrons) In which ⃗Ris time flux, σ&τare space and time coordinates on the string world sheet and p is momentum. Therefore, gravitational waves which travel from black hole to us including different fluxes of time which accompaniment propagated gravitational waves of momentum. As an observable factor, we can look at the 7 milliseconds difference of recorded at the time of arrival of the signals on September 14, 2015 by detector in Livingston before detector in Hanford. This difference of recorded time of signal GW150914 by LIGO cannot be due to warped space-time, because 3002 kilometers distance between two detectors with respect to the 1.3 billion light years (distance of black hole to detectors) is like zero! So, this 7 milliseconds difference between two time's fluxes can be due to gravitational waves propagated by different momentum which produced in different locations of the two merged black holes. We can see this phenomena in solar system like the Sun, Jupiter and our planet too, the Earth's gravity is shifting due to distribution of the mass/momentum in the Earth's core which resulted by the inner core dislocation and convection systems in the outer core. Because the inner core has a daily rotation around geophysical axis inverse of the Earth's spin due to its eccentricity and generates a huge variable momentum in the core [Gholibeigian, sabs.harvard.edu/abs/2012AGUFMPA23A1960G] - and therefore local gravity - inside the Earth is constantly changing. Results of the Gravity Recovery and Climate Experiment (GRACE) which lunched by NASA and the German Aerospace Center (DLR) in March 2002, approved this phenomena too. In other words generated momentum inside the large scale convection systems can be a source of coupled gravitational and electromagnetic fields in nature which has its own time flux.

Hybrid armature projectile

DOEpatents

Hawke, Ronald S.; Asay, James R.; Hall, Clint A.; Konrad, Carl H.; Sauve, Gerald L.; Shahinpoor, Mohsen; Susoeff, Allan R.

1993-01-01

A projectile for a railgun that uses a hybrid armature and provides a seed block around part of the outer surface of the projectile to seed the hybrid plasma brush. In addition, the hybrid armature is continuously vaporized to replenish plasma in a plasma armature to provide a tandem armature and provides a unique ridge and groove to reduce plasama blowby.

Hybrid armature projectile

DOEpatents

Hawke, R.S.; Asay, J.R.; Hall, C.A.; Konrad, C.H.; Sauve, G.L.; Shahinpoor, M.; Susoeff, A.R.

1993-03-02

A projectile for a railgun that uses a hybrid armature and provides a seed block around part of the outer surface of the projectile to seed the hybrid plasma brush. In addition, the hybrid armature is continuously vaporized to replenish plasma in a plasma armature to provide a tandem armature and provides a unique ridge and groove to reduce plasma blowby.

Unexplored biophysical problem of manned flight to Mars

NASA Astrophysics Data System (ADS)

Avakyan, Sergey; Voronin, Nikolai; Kovalenok, Vladimir; Trchounian, Armen

The presentation discusses so far unexplored biophysical problem of manned flight to the Mars, scheduled for the next decade. In long-term manned space flights on the orbital stations "Salyut-6" Soviet cosmonaut crews under the command of one of the co-authors (cosmonaut V.V. Kovalenok) had repeatedly observed the effect of certain geophysical conditions on the psychological state of each crew. These effects were coinciding with the increased intensity of global illumination in the upper ionosphere space on flight altitudes (300-360 km). It is important that, during all these periods, the geomagnetic pulsation's were completely absent. Previously a new but very important for long interplanetary expeditions problem of psychophysical state of the crew in the absence of alternating electromagnetic fields and radiation, including the ionosphere one, was first raised for evolutionarily adapted humanity. However, up to date, this subject, particularly during the long simulation experiments such as "Mars 500", which eliminates much of their value and contribution to the Mars mission, has almost no attention. Indeed, the obtained results have clearly shown that the cosmonaut crews in orbital flight, even deep one within geomagnetic sphere, might experience severe psychological discomfort, the nature of which is fully defined. This is the appearance of such rather unusual geophysical periods of different durations (from minutes to days) those are in the form of an almost complete lack of geomagnetic pulsations on the Earth. The aim is to confirm the need of considering possible pathological effects of the complete lack of rhythm forming, inherent for terrestrial environment geomagnetic pulsation's on psychological and physical state of the cosmonaut crew. This is important for the preparation and conducting the manned flights beyond the Earth's magnetosphere, particularly to the Mars. The influence of the presence of different types of geomagnetic pulsation's recorded by the Geophysical Observatory "Borok" of the Joint Institute of Physics of the Earth after O.Yu. Schmidt, Russian Academy of Sciences, on the statistics manifestations of various diseases for Murom City, located in the same region (Central Russia) at a distance of about 50 km has been investigated. It has been observed that the period of the absence of pulsation's is typical for the maximum number of events in the manifestation of the diseases, especially nervous ones. High-frequency pulsation's similar to frequency in the basic human biorhythms are absent in 60-100 % for neurasthenia and 100 % - for neurosis and psychosis. All these electromagnetic waves are usually the background for the earthling to disappear with the release of the interplanetary spacecraft beyond the magnetosphere, and after a few days of flight the cosmonauts will be out of the usual electromagnetic "noise", as well as outside the geomagnetic field. It is unknown however if under the simultaneous absence either the geomagnetic field or electromagnetic waves in a wide range of frequencies - from low (including those of the field of brain rhythms, heart, etc.) to the highest ones the extremely high frequencies affect the human organism upon the resonance effects on the body cells. Therefore, in the coming years, during the preparatory stages of the first interplanetary flight, it is required to study synergistic effects of exposure to the fields on human - under expected absence of the usual "sets" oscillations of electromagnetic fields, especially geomagnetic pulsations, when real background of hypo-magnetic field exists. It should be emphasized that the flights and landings on the Moon cannot be analogous for discussion of the situation, as the flights continued outside the magnetosphere of the Earth are less than a week. Most importantly, the Moon during each lunar month (29 days) for several days is trailing geomagnetic sphere.

The "Alfvén" proposal for the European Space Agency M5 Mission Call

NASA Astrophysics Data System (ADS)

Berthomier, M.; Fazakerley, A. N.

2017-12-01

The Alfvén mission objective is to elucidate the particle acceleration processes and their consequences for electromagnetic radiation and energy transport in strongly magnetised plasmas. The Earth's Auroral Acceleration Region is a unique laboratory for investigating these processes. The only way to distinguish between the models describing acceleration processes at the heart of Magnetosphere-Ionosphere Coupling is to combine high-time resolution in situ measurements (as pioneered by FAST), multi-point measurements (as pioneered by CLUSTER), and auroral arc imaging in one mission. Charged particle acceleration in strongly magnetized plasmas requires the conversion of electromagnetic energy into magnetic-field-aligned particle kinetic energy. Alfvén will measure for the first time the occurrence and distribution of small scale parallel electric fields in space and time. In order to determine the relative efficiency of the different conversion mechanisms, Alfvén will also measure the corresponding particle energy fluxes locally and into the aurora. Alfvén will discover how electromagnetic radiation is generated in the acceleration region and how it escapes. Alfvén will make key measurements of Auroral Kilometric Radiation needed to test competing models of wave generation, mode conversion and escape from their source region. These will reveal the mode conversion processes and which information is ultimately carried by the polarization of radio waves reaching free space. Alfvén will discover the global impact of particle acceleration on the dynamic coupling between a magnetized object and its plasma environment. Dual spacecraft measurements offer the unique opportunity to unambiguously determine which part of the energy flowing into the ionosphere is eventually dissipated in this collisional plasma and which part is transmitted to outflowing ions of ionospheric origin. The Alfvén mission design involves use of two simple identical spacecraft, a comprehensive suite of inter-calibrated particles and fields instruments, cutting edge auroral imaging, easily accessible orbits that frequently visit the region of scientific interest and straightforward operations.

Reflection of hierarchical medium structures of different scales in the space time data of wave fields distribution.

NASA Astrophysics Data System (ADS)

Hachay, Olga; Khachay, Andrey

2015-04-01

The last decades are characterized by active development of Earth's sciences. The modern research methods and technologies give the opportunity to obtain new data about the Earth's structure and processes, which occur in its interior. The conception development about the nonlinear geodynamics practically coincides with research of nonlinear processes in different parts of physics. In geology soliton and auto wave conceptions are developed, principles of synergetic and self organization become be used, in geodynamics the macro quantum behavior of large mass matter, which are in critical state, in geophysics the auto wave nature of geophysical fields is researched in a frame of a new structural model with hierarchical inclusions. It is very significant to define the time of reaction lagging, in spite of the influence on the massif can be assumed as elastic. The unique model which can explain that effect is a model of the massif with a hierarchic structure. We developed a mathematical algorithm using integral and integral-differential equations for 2-D model for two problems in a frequency domain: diffraction a sound wave and linear polarized transverse wave through a arbitrary hierarchy rank inclusion plunged in an N-layered medium. That algorithm differs from the fractal model approach by a freer selecting of heterogeneities position of each rank. And the second, the problem is solved in the dynamical approach. The higher the amount of the hierarchic ranks the more is the degree of nonlinearity of the massive response and the longer can be the time of massive reaction lag of the influence. For research of hierarchic medium we had developed an iterative algorithm for electromagnetic and seismic fields in the problem setting similar to analyze higher for layered-block models with homogeneous inclusions. We had developed an iterative algorithm of inverse problem solution for the same models, using the approach of three stage interpretation. For that we had developed a new integral differential equation for the theoretical inverse problem of 2-D electromagnetic field in a hierarchic inclusion, embedded in the N-layered medium. References: Hachay O.A. et al.(2008 a) Modeling of seismic and electromagnetic field in the hierarchic heterogeneous media. Proceedings of International conference. Ekaterinburg: IGF UB RAS Hachay O.A. et al. (2008 b).Complex electromagnetic and seismic method of research of the crust and Earth's mantle structure. Proceedings of International conference. Ekaterinburg: IGF UB RAS Hachay O.A. et al. (2013) Modeling of electromagnetic and seismic fields in hierarchic heterogeneous media. Bulletin of South Ural State University. Series:"Computational mathematics and Software Engineering". 2: 48-55.

Deep prospecting electromagnetic system and its application

NASA Astrophysics Data System (ADS)

Lin, J.; Liu, C.; Zhou, F.; Zhang, W.; Chen, J.; Xue, K.; Sun, C.; Xu, W.; Hu, R.

2011-12-01

Today mineral resource is becoming the impediment to the society development because less and less mineral resource can be available. People are trying all kinds of technological tools to find the mineral deposit concealed in deep lithosphere. Unfortunately, current technology can not meet the exploration requirement completely and it is still difficult to know whether a deep mineral deposit exists and how it is presented at a considered site. In order to meet the requirement of discovering the mineral deposit in the second mine prospecting space (500-2000m under earth surface), we developed a deep prospecting electromagnetic system (DPS-I). This system consists of an electromagnetic receiver array and a high-power transmitter. The receiver array consists of 24 sub-receivers and one controller and has up to 53 electromagnetic channels. The sub-receivers can be extended conveniently if the user would like and they communicate with the controller through a cable or wireless antenna. When the channel interval is set to typical value of 50 m, the system can cover 2500 m survey line at one arrangement with two magnetic records. Since the signals are collected at the same time some disturbances, such as time variable but space invariable noise, will be suppressed because they have almost the same effect to all channels. The transmitter is designed to be 45 KW of upper power limit so that strong signals will be detected. Series transmission technology is adopted to avoid unwieldiness of transmitter. In fact it is made of three portable transmission units and each one can work independently. The system can transmit several kinds of waves and records all samples of signals in time sequences. So it can work for different electromagnetic methods. The prior methods for our application are the combination of IP, CSAMT and MT. Utilizing joint inversion and model restriction, we can obtain more refined model at large depth than conventional exploration. We have applied this system in China to detect nickel ore, iron ore, geothermic water and formation buried in deep earth successfully with high resolution power and the largest depth of investigation exceeded 2000 m. The nickel ore is located at Hongqiling hill, Jilin province. The depth of its top surface is about 600 m and that of its bottom surface is about 900 m. The iron ore is located at Dataigou, Liaoning province. Its top surface is buried about 1200 m beneath the ground and its bottom surface is still not assured because the deepest bore didn't reach its bottom. According to the known information, the bottom surface is inferred to be deeper than 2000 m. The geothermic water is buried deeply about 1600 m beneath the ground, located at Baishan, Jilin province. A bore of 2200 m depth was dilled after our exploration and hot water flowed out from the bore. Although several power lines exist nearby the survey lines, we still observed obvious signals and find low resistivity region at the place where the ore and the water exist. These experiments show that our electromagnetic system is successful.

Molecularly Oriented Polymeric Thin Films for Space Applications

NASA Technical Reports Server (NTRS)

Fay, Catharine C.; Stoakley, Diane M.; St.Clair, Anne K.

1997-01-01

The increased commitment from NASA and private industry to the exploration of outer space and the use of orbital instrumentation to monitor the earth has focused attention on organic polymeric materials for a variety of applications in space. Some polymeric materials have exhibited short-term (3-5 yr) space environmental durability; however, future spacecraft are being designed with lifetimes projected to be 10-30 years. This gives rise to concern that material property change brought about during operation may result in unpredicted spacecraft performance. Because of their inherent toughness and flexibility, low density, thermal stability, radiation resistance and mechanical strength, aromatic polyimides have excellent potential use as advanced materials on large space structures. Also, there exists a need for high temperature (200-300 C) stable, flexible polymeric films that have high optical transparency in the 300-600nm range of the electromagnetic spectrum. Polymers suitable for these space applications were fabricated and characterized. Additionally, these polymers were molecularly oriented to further enhance their dimensional stability, stiffness, elongation and strength. Both unoriented and oriented polymeric thin films were also cryogenically treated to temperatures below -184 C to show their stability in cold environments and determine any changes in material properties.

Surface biosignatures of exo-Earths: Remote detection of extraterrestrial life

PubMed Central

Hegde, Siddharth; Paulino-Lima, Ivan G.; Kent, Ryan; Kaltenegger, Lisa; Rothschild, Lynn

2015-01-01

Exoplanet discovery has made remarkable progress, with the first rocky planets having been detected in the central star’s liquid water habitable zone. The remote sensing techniques used to characterize such planets for potential habitability and life rely solely on our understanding of life on Earth. The vegetation red edge from terrestrial land plants is often used as a direct signature of life, but it occupies only a small niche in the environmental parameter space that binds life on present-day Earth and has been widespread for only about 460 My. To more fully exploit the diversity of the one example of life known, we measured the spectral characteristics of 137 microorganisms containing a range of pigments, including ones isolated from Earth’s most extreme environments. Our database covers the visible and near-infrared to the short-wavelength infrared (0.35–2.5 µm) portions of the electromagnetic spectrum and is made freely available from biosignatures.astro.cornell.edu. Our results show how the reflectance properties are dominated by the absorption of light by pigments in the visible portion and by strong absorptions by the cellular water of hydration in the infrared (up to 2.5 µm) portion of the spectrum. Our spectral library provides a broader and more realistic guide based on Earth life for the search for surface features of extraterrestrial life. The library, when used as inputs for modeling disk-integrated spectra of exoplanets, in preparation for the next generation of space- and ground-based instruments, will increase the chances of detecting life. PMID:25775594

The Space Experiment PAMELA

NASA Astrophysics Data System (ADS)

Boezio, M.; Bonvicini, V.; Mocchiutti, E.; Schiavon, P.; Vacchi, A.; Zampa, G.; Zampa, N.; Bakaldin, A.; Galper, A. M.; Koldashov, S. V.; Korotkov, M. G.; Mikhailov, V. V.; Voronov, S. A.; Yurkin, Y.; Basili, A.; Bencardino, R.; Bongiorno, L.; Casolino, M.; de Pascale, M. P.; Furano, G.; Menicucci, A.; Minori, M.; Morselli, A.; Picozza, P.; Sparvoli, R.; Wischnewski, R.; Adriani, O.; Bonechi, L.; Bongi, M.; Giambi, F.; Papini, P.; Ricciarini, S. B.; Spillantini, P.; Straulino, S.; Taccetti, F.; Vannuccini, E.; Castellini, G.; Carlson, P.; Lund, J.; Lundquist, J.; Orsi, S.; Pearce, M.; Barbarino, G. C.; Campana, D.; Osteria, G.; Rossi, G.; Russo, S.; Boscherini, M.; Menn, W.; Simon, M.; Ricci, M.; Ambriola, M.; Bellotti, R.; Cafagna, F.; Circella, M.; de Marzo, C.; Giglietto, N.; Mirizzi, N.; Romita, M.; Spinelli, P.; Bogomolov, E.; Krutkov, S.; Vasiljev, G.; Bazilevskaja, G.; Grigorjeva, A.; Mukhametshin, R.; Stozhkov, Y.; Mitchell, J. W.; Streitmatter, R. E.; Stochaj, S. J.

2004-09-01

We present in this paper a status report of the space experiment PAMELA. PAMELA is a satellite-borne experiment which primarily aims to measure the antiproton and positron spectra in the cosmic radiation over a large energy range (from 80 MeV up to 190 GeV for antiprotons and from 50 MeV up to 270 GeV for positrons) and to search for antinuclei with a sensitivity of the order of 10-8 in the antihelium/helium ratio. In addition, it will measure the light nuclear component of cosmic rays and investigate phenomena connected with Solar and Earth physics. The apparatus will be installed onboard the polar orbiting Resurs DK1 satellite, which will be launched into space by a Soyuz TM2 rocket in 2004 from Baikonur cosmodrome in Kazakhstan, for a 3 year long mission. PAMELA consists of: a time of flight system, a transition radiation detector, a magnetic spectrometer, an anticoincidence detector, an electromagnetic imaging calorimeter, a shower tail catcher scintillator and a neutron detector.

Prospects for high accuracy time dissemination and synchronization using coded radar pulses from a low-earth orbiting spacecraft

NASA Technical Reports Server (NTRS)

Detoma, Edoardo V.; Dionisio, C.

1995-01-01

The radar (an acronym for radio detection and ranging) is an instrument developed just before the WW-II to precisely measure the position of an object (target) in space. This is done by emitting a narrow pulse of electromagnetic energy in the RF spectrum, receiving the return echo and measuring the time of flight in the two-way path from the emitter to the target. The propagation delay provides a measure of the range to the target, which is not in itself sufficient to uniquely locate the position of the same in space. However, if a directional antenna is used, the direction of the echo can be assessed by the antenna pointing angles. In this way the position of the target can be uniquely determined in space. How well this can be done is a function of the resolution of the measurements performed (range and direction, i.e.: angles); in turn, the resolution will dictate the time and frequency requirements of the reference oscillator.

Low-gravity Orbiting Research Laboratory Environment Potential Impact on Space Biology Research

NASA Technical Reports Server (NTRS)

Jules, Kenol

2006-01-01

One of the major objectives of any orbital space research platform is to provide a quiescent low gravity, preferably a zero gravity environment, to perform fundamental as well as applied research. However, small disturbances exist onboard any low earth orbital research platform. The impact of these disturbances must be taken into account by space research scientists during their research planning, design and data analysis in order to avoid confounding factors in their science results. The reduced gravity environment of an orbiting research platform in low earth orbit is a complex phenomenon. Many factors, among others, such as experiment operations, equipment operation, life support systems and crew activity (if it is a crewed platform), aerodynamic drag, gravity gradient, rotational effects as well as the vehicle structural resonance frequencies (structural modes) contribute to form the overall reduced gravity environment in which space research is performed. The contribution of these small disturbances or accelerations is precisely why the environment is NOT a zero gravity environment, but a reduced acceleration environment. This paper does not discuss other factors such as radiation, electromagnetic interference, thermal and pressure gradient changes, acoustic and CO2 build-up to name a few that affect the space research environment as well, but it focuses solely on the magnitude of the acceleration level found on orbiting research laboratory used by research scientists to conduct space research. For ease of analysis this paper divides the frequency spectrum relevant to most of the space research disciplines into three regimes: a) quasi-steady, b) vibratory and c) transient. The International Space Station is used as an example to illustrate the point. The paper discusses the impact of these three regimes on space biology research and results from space flown experiments are used to illustrate the potential negative impact of these disturbances (accelerations) on space biology research.

New calorimeters for space experiments: physics requirements and technological challenges

NASA Astrophysics Data System (ADS)

Marrocchesi, Pier Simone

2015-07-01

Direct measurements of charged cosmic radiation with instruments in Low Earth Orbit (LEO), or flying on balloons above the atmosphere, require the identification of the incident particle, the measurement of its energy and possibly the determination of its sign-of-charge. The latter information can be provided by a magnetic spectrometer together with a measurement of momentum. However, magnetic deflection in space experiments is at present limited to values of the Maximum Detectable Rigidity (MDR) hardly exceeding a few TV. Advanced calorimetric techniques are, at present, the only way to measure charged and neutral radiation at higher energies in the multi-TeV range. Despite their mass limitation, calorimeters may achieve a large geometric factor and provide an adequate proton background rejection factor, taking advantage of a fine granularity and imaging capabilities. In this lecture, after a brief introduction on electromagnetic and hadronic calorimetry, an innovative approach to the design of a space-borne, large acceptance, homogeneous calorimeter for the detection of high energy cosmic rays will be described.

Environmental assessment for the satellite power system concept development and evaluation program: nonmicrowave health and ecological effects

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

White, M R

1980-11-01

A Concept Development and Evaluation Program is being carried out for a proposed Satellite Power System (SPS). For purposes of this evaluation, a preliminary reference system has been developed. SPS, as described in the reference system, would collect solar energy on satellites in geosychronous orbit in space. The energy would be converted to microwaves and beamed to an earth-receiving antenna (rectenna). One task in the environmental part of the program is the assessment of the nonmicrowave effects on health and the environment. These effects would result from all phases of SPS development and operation. This report covers the current knowledgemore » regarding these effects, and is based on the reference system. The assessment is summarized as to scope, methodology, impacts of terrestrial development, launch and recovery of spacecraft, space activities (including health effects of the space environment, ionizing radiation, electromagnetic exposure, spacecraft charging and environmental interactions, occupational hazards, etc.) and construction and operation of rectenna (ground receiving station).« less

Electromagnetic Radiation in the Atmosphere Generated by Excess Negative Charge in a Nuclear-Electromagnetic Cascade

NASA Astrophysics Data System (ADS)

Malyshevsky, V. S.; Fomin, G. V.

2017-01-01

On the basis of the analytical model "PARMA" (PHITS-based Analytical Radiation Model in the Atmosphere), developed to model particle fluxes of secondary cosmic radiation in the Earth's atmosphere, we have calculated the characteristics of radio waves emitted by excess negative charge in an electromagnetic cascade. The results may be of use in an analysis of experimental data on radio emission of electron-photon showers in the atmosphere.

Comparison of Commercial EMI Test Techniques to NASA EMI Test Techniques

NASA Astrophysics Data System (ADS)

Smith, Valerie

2000-11-01

This systems report describes how the Optical Properties Monitor (OPM) experiment was developed. Pertinent design parameters are discussed, along with mission information and system requirements to successfully complete the mission. Environmental testing was performed on the OPM to certify it for spaceflight. This testing included vibration, thermal vacuum, electromagnetic interference and conductance, and toxicity tests. Instrument and monitor subsystem performances, including the reflectometer, vacuum ultraviolet, total integrated scatter, atomic oxygen monitor, irradiance monitor, and molecular contamination monitor during the mission are discussed. The OPM experiment was launched aboard the Space Shuttle on mission STS-81 in January 1997 and transferred to the Mir space station. An extravehicular activity (EVA) was performed in April 1997 to attach the OPM experiment to the outside of the Mir/Shuttle Docking Module for space environment exposure. The OPM conducted in situ measurements of a number of material samples. These data may be found in the OPM Science Report. OPM was retrieved during an EVA in January 1998 and was returned to Earth on board the Space Shuttle on mission STS-89.

Design of the Digital Satellite Link Interface for a System That Detects the Precursory Electromagnetic Emissions Associated with Earthquakes

DTIC Science & Technology

1986-12-01

earthquake that is likely to occur in a given louality [Ref. 8:p. 1082]. The accumulation law of seismotectonic movement relates the amount of...mechanism - fault creep anomaly - seismic wave velocity - geomagnetic field - telluric (earth) currents - electromagnetic emissions - resistivity of

System Report for the Optical Properties Monitor (OPM) Experiment

NASA Technical Reports Server (NTRS)

Hummer, L.

2001-01-01

This systems report describes how the Optical Properties Monitor (OPM) experiment was developed. Pertinent design parameters are discussed, along with mission information and system requirements to successfully complete the mission. Environmental testing was performed on the OPM to certify it for spaceflight. This testing included vibration, thermal vacuum, electromagnetic interference and conductance, and toxicity tests. Instrument and monitor subsystem performances, including the reflectometer, vacuum ultraviolet, total integrated scatter, atomic oxygen monitor, irradiance monitor, and molecular contamination monitor during the mission are discussed. The OPM experiment was launched aboard the Space Shuttle on mission STS-81 in January 1997 and transferred to the Mir space station. An extravehicular activity (EVA) was performed in April 1997 to attach the OPM experiment to the outside of the Mir/Shuttle Docking Module for space environment exposure. The OPM conducted in situ measurements of a number of material samples. These data may be found in the OPM Science Report. OPM was retrieved during an EVA in January 1998 and was returned to Earth on board the Space Shuttle on mission STS-89.

The High Energy Particle Detector on Board of the China Seismo-Electromagnetic Satellite

NASA Astrophysics Data System (ADS)

Sparvoli, Roberta; Palma, Francesco; Panico, Beatrice; Sotgiu, Alessandro; Vitale, Vincenzo

2016-08-01

The study of the Van Allen belts temporal stability is among the main objectives of the China Seismo- Electromagnetic Satellite (CSES) space mission, as well as the study of other electromagnetic disturbances with possible seismic origin. In parallel to this, the CSES mission will address issues of heliospheric and magnetospheric physics, by measuring the cosmic radiation around the Earth.The CSES satellite, developed by a Chinese-Italian collaboration, will be launched in the first half of 2017 and inserted into a circular Sun-synchronous orbit with 98° inclination and 500 km altitude. The expected lifetime is 5 years. CSES hosts several instruments on board: 2 magnetometers, an electric field detector, a plasma analyser, a Langmuir probe and a High-Energy Particle Detector (HEPD). The HEPD detector, responsibility of the Italian side of the CSES collaboration, will measure electrons (3 - 100 MeV) and protons (30 - 300 MeV) along CSES orbit. It consists of a segmented layer of plastic scintillators for the trigger and a calorimeter constituted by a tower of plastic scintillator counters and a LYSO plane. The direction of the incident particle is provided by two planes of double-side silicon micro-strip detectors placed in front of the trigger. Topic of this talk is the technical description of the HEPD and its main characteristics.

Research in space physics at the University of Iowa. [energetic particles and electric, magnetic, and electromagnetic fields

NASA Technical Reports Server (NTRS)

Vanallen, J. A.

1978-01-01

Specific fields of current investigation by satellite observation and ground-based radio-astronomical and optical techniques are discussed. Topics include: aspects of energetic particles trapped in the earth's magnetic field and transiently present in the outer magnetosphere and the solar, interplanetary, and terrestrial phenomena associated with them; plasma flows in the magnetosphere and the ionospheric effects of particle precipitation, with corresponding studies of the magnetosphere of Jupiter, Saturn, and possibly Uranus; the origin and propagation of very low frequency radio waves in the earth's magnetosphere and ionosphere; solar particle emissions and their interplanetary propagation and acceleration; solar modulation and the heliocentric radial dependence of the intensity of galactic cosmic rays; radio frequency emissions from the quintescent and flaring sun; shock waves in the interplanetary medium; radio emissions from Jupiter; and radio astronomy of pulsars, flare stars, and other stellar sources.

Astroparticles: Messengers from Outer Space

NASA Astrophysics Data System (ADS)

Desiati, Paolo

2016-07-01

Since Galileo pointed a spyglass toward the sky, 400 years ago, observations empowered by man-made instrumentation have provided us with an enormous leap in the knowledge of how the Universe functions. More and more powerful optical telescopes made it possible for us to reach the farthest corners of space. At the same time, the advances in microphysics and the discovery of the electromagnetic spectrum, made it possible to directly look at the Universe in a way that our eyes cannot see. The discoveries of the intimate structure of matter, of subatomic particles and of how they interact with each other, have led astronomers to use the smallest objects in Nature to observe the farthest reaches of the otherwise invisible Universe. Not unlike Galileo, today we observe Outer Space with visible light and beyond, across the entire electromagnetic spectrum, from long wavelength radio waves to short wavelength gamma rays. But also with instruments detecting cosmic rays (the atomic nuclei we know on Earth) neutrinos (neutral subatomic particles that interact very weakly with matter) and gravitational waves (perturbations of spacetime predicted by General Relativity). Each cosmic messenger provides us with a unique piece of information about their source and the history of their journey to us. Modern astrophysics has the challenging goal to collect as much information as possible from all those messengers, to reconstruct the story of the Universe and how it became what it is today. This journey started with the unsettling discovery that we are only one minuscule dot in the immensity of the Universe and yet we are able to observe objects that are far in space and time. This journey is yet to complete its course, and the more we advance our knowledge, the more we need to understand. This interdisciplinary talk provides an overview of this journey and the future perspectives.

Earth Conductivity Estimation from Through-the-Earth Measurements of 94 Coal Mines Using Different Electromagnetic Models

PubMed Central

Yan, Lincan; Waynert, Joseph; Sunderman, Carl

2015-01-01

Through-the-Earth (TTE) communication systems require minimal infrastructure to operate. Hence, they are assumed to be more survivable and more conventional than other underground mine communications systems. This survivability is a major advantage for TTE systems. In 2006, Congress passed the Mine Improvement and New Emergency Response Act (MINER Act), which requires all underground coal mines to install wireless communications systems. The intent behind this mandate is for trapped miners to be able to communicate with surface personnel after a major accident-hence, the interest in TTE communications. To determine the likelihood of establishing a TTE communication link, it would be ideal to be able to predict the apparent conductivity of the overburden above underground mines. In this paper, all 94 mine TTE measurement data collected by Bureau of Mines in the 1970s and early 1980s, are analyzed for the first time to determine the apparent conductivity of the overburden based on three different models: a homogenous half-space model, a thin sheet model, and an attenuation factor or Q-factor model. A statistical formula is proposed to estimate the apparent earth conductivity for a specific mine based on the TTE modeling results given the mine depth and signal frequency. PMID:26213457

Earth Conductivity Estimation from Through-the-Earth Measurements of 94 Coal Mines Using Different Electromagnetic Models.

PubMed

Yan, Lincan; Waynert, Joseph; Sunderman, Carl

2014-10-01

Through-the-Earth (TTE) communication systems require minimal infrastructure to operate. Hence, they are assumed to be more survivable and more conventional than other underground mine communications systems. This survivability is a major advantage for TTE systems. In 2006, Congress passed the Mine Improvement and New Emergency Response Act (MINER Act), which requires all underground coal mines to install wireless communications systems. The intent behind this mandate is for trapped miners to be able to communicate with surface personnel after a major accident-hence, the interest in TTE communications. To determine the likelihood of establishing a TTE communication link, it would be ideal to be able to predict the apparent conductivity of the overburden above underground mines. In this paper, all 94 mine TTE measurement data collected by Bureau of Mines in the 1970s and early 1980s, are analyzed for the first time to determine the apparent conductivity of the overburden based on three different models: a homogenous half-space model, a thin sheet model, and an attenuation factor or Q-factor model. A statistical formula is proposed to estimate the apparent earth conductivity for a specific mine based on the TTE modeling results given the mine depth and signal frequency.

Quantum detection of wormholes.

PubMed

Sabín, Carlos

2017-04-06

We show how to use quantum metrology to detect a wormhole. A coherent state of the electromagnetic field experiences a phase shift with a slight dependence on the throat radius of a possible distant wormhole. We show that this tiny correction is, in principle, detectable by homodyne measurements after long propagation lengths for a wide range of throat radii and distances to the wormhole, even if the detection takes place very far away from the throat, where the spacetime is very close to a flat geometry. We use realistic parameters from state-of-the-art long-baseline laser interferometry, both Earth-based and space-borne. The scheme is, in principle, robust to optical losses and initial mixedness.

Living with a Star: New Opportunities in Sun-Climate Research

NASA Technical Reports Server (NTRS)

2003-01-01

Living With a Star is a NASA initiative employing the combination of dedicated spacecraft with targeted research and modeling efforts to improve what we know of solar effects of all kinds on the Earth and its surrounding space environment, with particular emphasis on those that have significant practical impacts on life and society. The highest priority among these concerns is the subject of this report: the potential effects of solar variability on regional and global climate, including the extent to which solar variability has contributed to the well-documented warming of the Earth in the last 100 years. Understanding how the climate system reacts to external forcing from the Sun will also greatly improve our knowledge of how climate will respond to other climate drivers, including those of anthropogenic origin. A parallel element of the LWS program addresses solar effects on space weather : the impulsive emissions of charged particles, short-wave electromagnetic radiation and magnetic disturbances in the upper atmosphere and near-Earth environment that also affect life and society. These include a wide variety of solar impacts on aeronautics, astronautics, electric power transmission, and national defense. Specific examples are (1) the impacts of potentially- damaging high energy radiation and atomic particles of solar origin on satellites and satellite operations, spacecraft electronics systems and components, electronic communications, electric power distribution grids, navigational and GPS systems, and high altitude aircraft; and (2) the threat of sporadic, high-energy solar radiation to astronauts and high altitude aircraft passengers and crews. Elements of the LWS program include an array of dedicated spacecraft in near- Earth and near-Sun orbits that will closely study and observe both the Sun itself and the impacts of its variations on the Earth's radiation belts and magnetosphere, the upper atmosphere, and ionosphere. These spacecraft, positioned to study and monitor changing conditions in the Sun-Earth neighborhood, will also serve as sentinels of solar storms and impulsive events.

Multiply charged ion generation according to magnetic field configurations in Hall thruster plasmas

NASA Astrophysics Data System (ADS)

Kim, Holak; Lee, Seunghun; Kim, Junbum; Lim, Youbong; Choe, Wonho; KIMS Collaboration

2016-09-01

Plasma propulsion is the most promising techniques to operate satellites for low earth orbit as well as deep space exploration. A typical plasma propulsion system is Hall thruster (HT) that uses crossed electromagnetic fields to ionize a propellant gas and to accelerate the ionized gas. In HT the tailoring of magnetic fields is significant due to that the electron confinement in the electromagnetic fields affects thruster performances such as thrust force, specific impulse, power efficiency, and life time. We designed an anode layer HT (TAL) with the magnetic field tailoring. The TAL is possible to keep discharge in 1 2 kilovolts, which voltage is useful to obtain high specific impulse The magnetic field tailoring is adapted to minimize undesirable heat dissipations and secondary electron emissions at a wall surrounding plasma In presentation, we will report TAL performances including thrust force, specific impulse, and anode efficiency measured by a pendulum thrust stand. This mechanical measurement will be compared to the plasma diagnostics conducted by angular Faraday probe, retarding potential analyzer, and ExB probe Grant No. 2014M1A3A3A02034510.

Measuring the Earth System in a Time of Global Environmental Change with Image Spectroscopy

NASA Technical Reports Server (NTRS)

Green, Robert O.

2005-01-01

Measuring the Earth system in a time of global environmental change. Imaging Spectroscopy enables remote measurement. Remote Measurement determination of the properties of the Earth's surface and atmosphere through the physics, chemistry and biology of the interaction of electromagnetic energy with matter.

Generation of electromagnetic emission during the injection of dense supersonic plasma flows into arched magnetic field

NASA Astrophysics Data System (ADS)

Viktorov, Mikhail; Golubev, Sergey; Mansfeld, Dmitry; Vodopyanov, Alexander

2016-04-01

Interaction of dense supersonic plasma flows with an inhomogeneous arched magnetic field is one of the key problems in near-Earth and space plasma physics. It can influence on the energetic electron population formation in magnetosphere of the Earth, movement of plasma flows in magnetospheres of planets, energy release during magnetic reconnection, generation of electromagnetic radiation and particle precipitation during solar flares eruption. Laboratory study of this interaction is of big interest to determine the physical mechanisms of processes in space plasmas and their detailed investigation under reproducible conditions. In this work a new experimental approach is suggested to study interaction of supersonic (ion Mach number up to 2.7) dense (up to 1015 cm-3) plasma flows with inhomogeneous magnetic field (an arched magnetic trap with a field strength up to 3.3 T) which opens wide opportunities to model space plasma processes in laboratory conditions. Fully ionized plasma flows with density from 1013 cm-3 to 1015 cm-3 are created by plasma generator on the basis of pulsed vacuum arc discharge. Then plasma is injected in an arched open magnetic trap along or across magnetic field lines. The filling of the arched magnetic trap with dense plasma and further magnetic field lines break by dense plasma flow were experimentally demonstrated. The process of plasma deceleration during the injection of plasma flow across the magnetic field lines was experimentally demonstrated. Pulsed plasma microwave emission at the electron cyclotron frequency range was observed. It was shown that frequency spectrum of plasma emission is determined by position of deceleration region in the magnetic field of the magnetic arc, and is affected by plasma density. Frequency spectrum shifts to higher frequencies with increasing of arc current (plasma density) because the deceleration region of plasma flow moves into higher magnetic field. The observed emission can be related to the cyclotron mechanism of generation by non-equilibrium energetic electrons in dense plasma. The reported study was funded by RFBR, according to the research project No. 16-32-60056 mol_a_dk.

Some anticipated contributions to core fluid dynamics from the GRM

NASA Technical Reports Server (NTRS)

Vanvorhies, C.

1985-01-01

It is broadly maintained that the secular variation (SV) of the large scale geomagnetic field contains information on the fluid dynamics of Earth's electrically conducting outer core. The electromagnetic theory appropriate to a simple Earth model has recently been combined with reduced geomagnetic data in order to extract some of this information and ascertain its significance. The simple Earth model consists of a rigid, electrically insulating mantle surrounding a spherical, inviscid, and perfectly conducting liquid outer core. This model was tested against seismology by using truncated spherical harmonic models of the observed geomagnetic field to locate Earth's core-mantle boundary, CMB. Further electromagnetic theory has been developed and applied to the problem of estimating the horizontal fluid motion just beneath CMB. Of particular geophysical interest are the hypotheses that these motions: (1) include appreciable surface divergence indicative of vertical motion at depth, and (2) are steady for time intervals of a decade or more. In addition to the extended testing of the basic Earth model, the proposed GRM provides a unique opportunity to test these dynamical hypotheses.

KSC-01pp1053

NASA Image and Video Library

2001-05-31

The first stage of the Geostationary Operational Environmental Satellite-M (GOES-M) Atlas II rocket is lifted to a vertical position at the gantry on Complex 36-A, Cape Canaveral Air Force Station. It will be raised and lifted up the gantry for mating with other stages. The last in the current series of advanced geostationary weather satellites in service, GOES-M has a new instrument not on earlier spacecraft, a Solar X-ray Imager that can be used in forecasting space weather, the effects of solar storms that create electromagnetic disturbances on earth that affect other satellites, communications and power grids. GOES-M is scheduled to launch from Cape Canaveral Air Force Station July 15

KSC-01PP1054

NASA Image and Video Library

2001-05-31

The first stage of the Geostationary Operational Environmental Satellite-M (GOES-M) Atlas II rocket is raised to a nearly vertical position on the gantry on Complex 36-A, Cape Canaveral Air Force Station. It will be raised and lifted up the gantry for mating with other stages. The last in the current series of advanced geostationary weather satellites in service, GOES-M has a new instrument not on earlier spacecraft, a Solar X-ray Imager that can be used in forecasting space weather, the effects of solar storms that create electromagnetic disturbances on earth that affect other satellites, communications and power grids. GOES-M is scheduled to launch from Cape Canaveral Air Force Station July 15

Numerical results for near surface time domain electromagnetic exploration: a full waveform approach

NASA Astrophysics Data System (ADS)

Sun, H.; Li, K.; Li, X., Sr.; Liu, Y., Sr.; Wen, J., Sr.

2015-12-01

Time domain or Transient electromagnetic (TEM) survey including types with airborne, semi-airborne and ground play important roles in applicants such as geological surveys, ground water/aquifer assess [Meju et al., 2000; Cox et al., 2010], metal ore exploration [Yang and Oldenburg, 2012], prediction of water bearing structures in tunnels [Xue et al., 2007; Sun et al., 2012], UXO exploration [Pasion et al., 2007; Gasperikova et al., 2009] etc. The common practice is introducing a current into a transmitting (Tx) loop and acquire the induced electromagnetic field after the current is cut off [Zhdanov and Keller, 1994]. The current waveforms are different depending on instruments. Rectangle is the most widely used excitation current source especially in ground TEM. Triangle and half sine are commonly used in airborne and semi-airborne TEM investigation. In most instruments, only the off time responses are acquired and used in later analysis and data inversion. Very few airborne instruments acquire the on time and off time responses together. Although these systems acquire the on time data, they usually do not use them in the interpretation.This abstract shows a novel full waveform time domain electromagnetic method and our recent modeling results. The benefits comes from our new algorithm in modeling full waveform time domain electromagnetic problems. We introduced the current density into the Maxwell's equation as the transmitting source. This approach allows arbitrary waveforms, such as triangle, half-sine, trapezoidal waves or scatter record from equipment, being used in modeling. Here, we simulate the establishing and induced diffusion process of the electromagnetic field in the earth. The traditional time domain electromagnetic with pure secondary fields can also be extracted from our modeling results. The real time responses excited by a loop source can be calculated using the algorithm. We analyze the full time gates responses of homogeneous half space and two layered models with half sine current waveform as examples. We find the on time responses are quite sensitive to resistivity or depth changes. The results show the potential use of full waveform responses in time domain electromagnetic surveys.

NASA's BARREL Mission in Sweden

NASA Image and Video Library

2017-12-08

Prior to launch, the BARREL team works on the payload from the launch pad at Esrange Space Center near Kiruna, Sweden. The BARREL team is at Esrange Space Center launching a series of six scientific payloads on miniature scientific balloons. The NASA-funded BARREL – which stands for Balloon Array for Radiation-belt Relativistic Electron Losses – primarily measures X-rays in Earth’s atmosphere near the North and South Poles. These X-rays are produced by electrons raining down into the atmosphere from two giant swaths of radiation that surround Earth, called the Van Allen belts. Learning about the radiation near Earth helps us to better protect our satellites. Several of the BARREL balloons also carry instruments built by undergraduate students to measure the total electron content of Earth’s ionosphere, as well as the low-frequency electromagnetic waves that help to scatter electrons into Earth’s atmosphere. Though about 90 feet in diameter, the BARREL balloons are much smaller than standard football stadium-sized scientific balloons. This is the fourth campaign for the BARREL mission. BARREL is led by Dartmouth College in Hanover, New Hampshire. The undergraduate student instrument team is led by the University of Houston and funded by the Undergraduate Student Instrument Project out of NASA’s Wallops Flight Facility. For more information on NASA’s scientific balloon program, visit: www.nasa.gov/scientificballoons. Image credit: NASA/Dartmouth/Robyn Millan NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

NASA's BARREL Mission in Sweden

NASA Image and Video Library

2017-12-08

The BARREL team prepares to launch their third payload from Esrange Space Center near Kiruna, Sweden, on Aug. 21, 2016. The BARREL team is at Esrange Space Center launching a series of six scientific payloads on miniature scientific balloons. The NASA-funded BARREL – which stands for Balloon Array for Radiation-belt Relativistic Electron Losses – primarily measures X-rays in Earth’s atmosphere near the North and South Poles. These X-rays are produced by electrons raining down into the atmosphere from two giant swaths of radiation that surround Earth, called the Van Allen belts. Learning about the radiation near Earth helps us to better protect our satellites. Several of the BARREL balloons also carry instruments built by undergraduate students to measure the total electron content of Earth’s ionosphere, as well as the low-frequency electromagnetic waves that help to scatter electrons into Earth’s atmosphere. Though about 90 feet in diameter, the BARREL balloons are much smaller than standard football stadium-sized scientific balloons. This is the fourth campaign for the BARREL mission. BARREL is led by Dartmouth College in Hanover, New Hampshire. The undergraduate student instrument team is led by the University of Houston and funded by the Undergraduate Student Instrument Project out of NASA’s Wallops Flight Facility. For more information on NASA’s scientific balloon program, visit: www.nasa.gov/scientificballoons. Credit: NASA/University of Houston/Michael Greer NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

NASA's BARREL Mission in Sweden

NASA Image and Video Library

2017-12-08

The BARREL team inflates the balloon to launch their fifth scientific payload from Esrange Space Center near Kiruna, Sweden, on Aug. 24, 2016. The BARREL team is at Esrange Space Center launching a series of six scientific payloads on miniature scientific balloons. The NASA-funded BARREL – which stands for Balloon Array for Radiation-belt Relativistic Electron Losses – primarily measures X-rays in Earth’s atmosphere near the North and South Poles. These X-rays are produced by electrons raining down into the atmosphere from two giant swaths of radiation that surround Earth, called the Van Allen belts. Learning about the radiation near Earth helps us to better protect our satellites. Several of the BARREL balloons also carry instruments built by undergraduate students to measure the total electron content of Earth’s ionosphere, as well as the low-frequency electromagnetic waves that help to scatter electrons into Earth’s atmosphere. Though about 90 feet in diameter, the BARREL balloons are much smaller than standard football stadium-sized scientific balloons. This is the fourth campaign for the BARREL mission. BARREL is led by Dartmouth College in Hanover, New Hampshire. The undergraduate student instrument team is led by the University of Houston and funded by the Undergraduate Student Instrument Project out of NASA’s Wallops Flight Facility. For more information on NASA’s scientific balloon program, visit: www.nasa.gov/scientificballoons. Credit: NASA/University of Houston/Michael Greer NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

A Determination of the Risk of Intentional and Unintentional Electromagnetic Radiation Emitters Degrading Installed Components in Closed Electromagnetic Environments

DTIC Science & Technology

2015-06-01

shield that tends to lower the EM levels at the surface of the Earth (Christopoulos 2007). It is important to note for the purposes of this paper...ELECTROMAGNETIC ENVIRONMENTS 5. FUNDING NUMBERS 6. AUTHOR( S ) Jared A. Johnson 7. PERFORMING ORGANIZATION NAME( S ) AND ADDRESS(ES) Naval Postgraduate School...Monterey, CA 93943-5000 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING /MONITORING AGENCY NAME( S ) AND ADDRESS(ES) N/A 10. SPONSORING

Measurement of electromagnetic fields over a small electrolytic tank

NASA Astrophysics Data System (ADS)

Caffey, T. W. H.; Morris, H. E.

1990-12-01

In 1986, Hart proposed a large, hemispherical electrolytic tank and the use of the Surface Electrical Potential method with which to study resistivity changes due to energy-extraction processes in the earth. A second method for the inference of underground resistivity changes, the Controlled Source Audio-MagnetoTelluric method, has been widely used in the field. This method uses measurements of the electromagnetic field from a surface dipole, rather than the surface potential distribution from a buried vertical electrode, as the basis of the technique. If both SEP and CSAMT could be applied to the same model structure in the same electrolytic tank, it would seem that the diagnostic information would be enhanced over the use of each technique separately. Accordingly, the specific objectives were: to determine to what radial extent the bowl could be used as a homogeneous half-space; and to demonstrate acceptable accuracy by measuring the effect of a conducting target immersed in the bowl and comparing the measurements with numerical modeling. Electromagnetic fields over an electrolytic tank have been measured by others, and this report begins with a comparative summary of both prior and present work. The next section presents the formulas for the electromagnetic fields, and explains the choice of a particular method of measuring apparent resistivity. The field theory is also used in the subsequent section to provide error estimates needed for design guidance. The following sections describe the measurements, and the considerations for a larger facility. The appendices include the derivatives of the fields, the electrolyte characteristics, a description of the apparatus, and calibration methods.

Electromagnetic synchronisation of clocks with finite separation in a rotating system

NASA Astrophysics Data System (ADS)

Cohen, J. M.; Moses, H. E.; Rosenblum, A.

1984-11-01

For clocks on the vertices of a triangle, it is shown that clock synchronisation using electromagnetic signals between finitely spaced clocks in a rotating frame leads to the same synchronization error as a closely spaced band of clocks along the same light path. In addition, the above result is generalized to n equally spaced clocks.

Compilation of 3D global conductivity model of the Earth for space weather applications

NASA Astrophysics Data System (ADS)

Alekseev, Dmitry; Kuvshinov, Alexey; Palshin, Nikolay

2015-07-01

We have compiled a global three-dimensional (3D) conductivity model of the Earth with an ultimate goal to be used for realistic simulation of geomagnetically induced currents (GIC), posing a potential threat to man-made electric systems. Bearing in mind the intrinsic frequency range of the most intense disturbances (magnetospheric substorms) with typical periods ranging from a few minutes to a few hours, the compiled 3D model represents the structure in depth range of 0-100 km, including seawater, sediments, earth crust, and partly the lithosphere/asthenosphere. More explicitly, the model consists of a series of spherical layers, whose vertical and lateral boundaries are established based on available data. To compile a model, global maps of bathymetry, sediment thickness, and upper and lower crust thicknesses as well as lithosphere thickness are utilized. All maps are re-interpolated on a common grid of 0.25×0.25 degree lateral spacing. Once the geometry of different structures is specified, each element of the structure is assigned either a certain conductivity value or conductivity versus depth distribution, according to available laboratory data and conversion laws. A numerical formalism developed for compilation of the model, allows for its further refinement by incorporation of regional 3D conductivity distributions inferred from the real electromagnetic data. So far we included into our model four regional conductivity models, available from recent publications, namely, surface conductance model of Russia, and 3D conductivity models of Fennoscandia, Australia, and northwest of the United States.

The PROCESS experiment: amino and carboxylic acids under Mars-like surface UV radiation conditions in low-earth orbit.

PubMed

Noblet, Audrey; Stalport, Fabien; Guan, Yuan Yong; Poch, Olivier; Coll, Patrice; Szopa, Cyril; Cloix, Mégane; Macari, Frédérique; Raulin, Francois; Chaput, Didier; Cottin, Hervé

2012-05-01

The search for organic molecules at the surface of Mars is a top priority of the next Mars exploration space missions: Mars Science Laboratory (NASA) and ExoMars (ESA). The detection of organic matter could provide information about the presence of a prebiotic chemistry or even biological activity on this planet. Therefore, a key step in interpretation of future data collected by these missions is to understand the preservation of organic matter in the martian environment. Several laboratory experiments have been devoted to quantifying and qualifying the evolution of organic molecules under simulated environmental conditions of Mars. However, these laboratory simulations are limited, and one major constraint is the reproduction of the UV spectrum that reaches the surface of Mars. As part of the PROCESS experiment of the European EXPOSE-E mission on board the International Space Station, a study was performed on the photodegradation of organics under filtered extraterrestrial solar electromagnetic radiation that mimics Mars-like surface UV radiation conditions. Glycine, serine, phthalic acid, phthalic acid in the presence of a mineral phase, and mellitic acid were exposed to these conditions for 1.5 years, and their evolution was determined by Fourier transform infrared spectroscopy after their retrieval. The results were compared with data from laboratory experiments. A 1.5-year exposure to Mars-like surface UV radiation conditions in space resulted in complete degradation of the organic compounds. Half-lives between 50 and 150 h for martian surface conditions were calculated from both laboratory and low-Earth orbit experiments. The results highlight that none of those organics are stable under low-Earth orbit solar UV radiation conditions.

NASA's BARREL Mission in Sweden

NASA Image and Video Library

2017-12-08

Four reindeer walk past the BARREL payload on the launch pad at Esrange Space Center near Kiruna, Sweden. The BARREL team is at Esrange Space Center launching a series of six scientific payloads on miniature scientific balloons. The NASA-funded BARREL – which stands for Balloon Array for Radiation-belt Relativistic Electron Losses – primarily measures X-rays in Earth’s atmosphere near the North and South Poles. These X-rays are produced by electrons raining down into the atmosphere from two giant swaths of radiation that surround Earth, called the Van Allen belts. Learning about the radiation near Earth helps us to better protect our satellites. Several of the BARREL balloons also carry instruments built by undergraduate students to measure the total electron content of Earth’s ionosphere, as well as the low-frequency electromagnetic waves that help to scatter electrons into Earth’s atmosphere. Though about 90 feet in diameter, the BARREL balloons are much smaller than standard football stadium-sized scientific balloons. This is the fourth campaign for the BARREL mission. BARREL is led by Dartmouth College in Hanover, New Hampshire. The undergraduate student instrument team is led by the University of Houston and funded by the Undergraduate Student Instrument Project out of NASA’s Wallops Flight Facility. For more information on NASA’s scientific balloon program, visit: www.nasa.gov/scientificballoons. Image credit: NASA/University of Houston/Samar Mathur NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

NASA's BARREL Mission in Sweden

NASA Image and Video Library

2017-12-08

A member of the BARREL team prepares a payload for launch from Esrange Space Center on Aug. 29, 2016. Throughout August 2016, the BARREL team was at Esrange Space Center near Kiruna, Sweden, launching a series of six scientific payloads on miniature scientific balloons. The NASA-funded BARREL – which stands for Balloon Array for Radiation-belt Relativistic Electron Losses – primarily measures X-rays in Earth’s atmosphere near the North and South Poles. These X-rays are produced by electrons raining down into the atmosphere from two giant swaths of radiation that surround Earth, called the Van Allen belts. Learning about the radiation near Earth helps us to better protect our satellites. Several of the BARREL balloons also carried instruments built by undergraduate students to measure the total electron content of Earth’s ionosphere, as well as the low-frequency electromagnetic waves that help to scatter electrons into Earth’s atmosphere. Though about 90 feet in diameter, the BARREL balloons are much smaller than standard football stadium-sized scientific balloons. This is the fourth campaign for the BARREL mission. BARREL is led by Dartmouth College in Hanover, New Hampshire. The undergraduate student instrument team is led by the University of Houston and funded by the Undergraduate Student Instrument Project out of NASA’s Wallops Flight Facility. For more information on NASA’s scientific balloon program, visit: www.nasa.gov/scientificballoons. Credit: NASA/Dartmouth/Alexa Halford NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

NASA's BARREL Mission in Sweden

NASA Image and Video Library

2017-12-08

A BARREL payload sits on the launch pad at Esrange Space Center near Kiruna, Sweden. The BARREL team is at Esrange Space Center launching a series of six scientific payloads on miniature scientific balloons. The NASA-funded BARREL – which stands for Balloon Array for Radiation-belt Relativistic Electron Losses – primarily measures X-rays in Earth’s atmosphere near the North and South Poles. These X-rays are produced by electrons raining down into the atmosphere from two giant swaths of radiation that surround Earth, called the Van Allen belts. Learning about the radiation near Earth helps us to better protect our satellites. Several of the BARREL balloons also carry instruments built by undergraduate students to measure the total electron content of Earth’s ionosphere, as well as the low-frequency electromagnetic waves that help to scatter electrons into Earth’s atmosphere. Though about 90 feet in diameter, the BARREL balloons are much smaller than standard football stadium-sized scientific balloons. This is the fourth campaign for the BARREL mission. BARREL is led by Dartmouth College in Hanover, New Hampshire. The undergraduate student instrument team is led by the University of Houston and funded by the Undergraduate Student Instrument Project out of NASA’s Wallops Flight Facility. For more information on NASA’s scientific balloon program, visit: www.nasa.gov/scientificballoons. Image credit: NASA/University of Houston/Edgar Bering NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

NASA's BARREL Mission in Sweden

NASA Image and Video Library

2017-12-08

A BARREL team member watches as one of their payloads launches from Esrange Space Center on Aug. 29, 2016. Throughout August 2016, the BARREL team was at Esrange Space Center near Kiruna, Sweden, launching a series of six scientific payloads on miniature scientific balloons. The NASA-funded BARREL – which stands for Balloon Array for Radiation-belt Relativistic Electron Losses – primarily measures X-rays in Earth’s atmosphere near the North and South Poles. These X-rays are produced by electrons raining down into the atmosphere from two giant swaths of radiation that surround Earth, called the Van Allen belts. Learning about the radiation near Earth helps us to better protect our satellites. Several of the BARREL balloons also carried instruments built by undergraduate students to measure the total electron content of Earth’s ionosphere, as well as the low-frequency electromagnetic waves that help to scatter electrons into Earth’s atmosphere. Though about 90 feet in diameter, the BARREL balloons are much smaller than standard football stadium-sized scientific balloons. This is the fourth campaign for the BARREL mission. BARREL is led by Dartmouth College in Hanover, New Hampshire. The undergraduate student instrument team is led by the University of Houston and funded by the Undergraduate Student Instrument Project out of NASA’s Wallops Flight Facility. For more information on NASA’s scientific balloon program, visit: www.nasa.gov/scientificballoons. Credit: NASA/Dartmouth/Alexa Halford NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

NASA's BARREL Mission in Sweden

NASA Image and Video Library

2017-12-08

A BARREL balloon inflates on the launch pad at Esrange Space Center on Aug. 29, 2016. Throughout August 2016, the BARREL team was at Esrange Space Center near Kiruna, Sweden, launching a series of six scientific payloads on miniature scientific balloons. The NASA-funded BARREL – which stands for Balloon Array for Radiation-belt Relativistic Electron Losses – primarily measures X-rays in Earth’s atmosphere near the North and South Poles. These X-rays are produced by electrons raining down into the atmosphere from two giant swaths of radiation that surround Earth, called the Van Allen belts. Learning about the radiation near Earth helps us to better protect our satellites. Several of the BARREL balloons also carried instruments built by undergraduate students to measure the total electron content of Earth’s ionosphere, as well as the low-frequency electromagnetic waves that help to scatter electrons into Earth’s atmosphere. Though about 90 feet in diameter, the BARREL balloons are much smaller than standard football stadium-sized scientific balloons. This is the fourth campaign for the BARREL mission. BARREL is led by Dartmouth College in Hanover, New Hampshire. The undergraduate student instrument team is led by the University of Houston and funded by the Undergraduate Student Instrument Project out of NASA’s Wallops Flight Facility. For more information on NASA’s scientific balloon program, visit: www.nasa.gov/scientificballoons. Credit: NASA/Dartmouth/Alexa Halford NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

NASA's BARREL Mission in Sweden

NASA Image and Video Library

2017-12-08

The first BARREL balloon is inflated just before its launch on Aug. 13, 2016, from Esrange Space Center near Kiruna, Sweden. The BARREL team is at Esrange Space Center launching a series of six scientific payloads on miniature scientific balloons. The NASA-funded BARREL – which stands for Balloon Array for Radiation-belt Relativistic Electron Losses – primarily measures X-rays in Earth’s atmosphere near the North and South Poles. These X-rays are produced by electrons raining down into the atmosphere from two giant swaths of radiation that surround Earth, called the Van Allen belts. Learning about the radiation near Earth helps us to better protect our satellites. Several of the BARREL balloons also carry instruments built by undergraduate students to measure the total electron content of Earth’s ionosphere, as well as the low-frequency electromagnetic waves that help to scatter electrons into Earth’s atmosphere. Though about 90 feet in diameter, the BARREL balloons are much smaller than standard football stadium-sized scientific balloons. This is the fourth campaign for the BARREL mission. BARREL is led by Dartmouth College in Hanover, New Hampshire. The undergraduate student instrument team is led by the University of Houston and funded by the Undergraduate Student Instrument Project out of NASA’s Wallops Flight Facility. For more information on NASA’s scientific balloon program, visit: www.nasa.gov/scientificballoons. Image credit: NASA/University of Houston/Edgar Bering NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

NASA's BARREL Mission in Sweden

NASA Image and Video Library

2017-12-08

A BARREL payload sits on the launch pad at Esrange Space Center near Kiruna, Sweden. The BARREL team is at Esrange Space Center launching a series of six scientific payloads on miniature scientific balloons. The NASA-funded BARREL – which stands for Balloon Array for Radiation-belt Relativistic Electron Losses – primarily measures X-rays in Earth’s atmosphere near the North and South Poles. These X-rays are produced by electrons raining down into the atmosphere from two giant swaths of radiation that surround Earth, called the Van Allen belts. Learning about the radiation near Earth helps us to better protect our satellites. Several of the BARREL balloons also carry instruments built by undergraduate students to measure the total electron content of Earth’s ionosphere, as well as the low-frequency electromagnetic waves that help to scatter electrons into Earth’s atmosphere. Though about 90 feet in diameter, the BARREL balloons are much smaller than standard football stadium-sized scientific balloons. This is the fourth campaign for the BARREL mission. BARREL is led by Dartmouth College in Hanover, New Hampshire. The undergraduate student instrument team is led by the University of Houston and funded by the Undergraduate Student Instrument Project out of NASA’s Wallops Flight Facility. For more information on NASA’s scientific balloon program, visit: www.nasa.gov/scientificballoons. Image credit: NASA/Dartmouth/Robyn Millan NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Skirted projectiles for railguns

DOEpatents

Hawke, Ronald S.; Susoeff, Allan R.

1994-01-01

A single skirt projectile (20) having an insulating skirt (22) at its rear, or a dual trailing skirt projectile (30, 40, 50, 60) having an insulating skirt (32, 42, 52, 62) succeeded by an arc extinguishing skirt (34, 44, 54, 64), is accelerated by a railgun accelerator 10 having a pair of parallel conducting rails (1a, 1b) which are separated by insulating wall spacers (11). The insulating skirt (22, 32, 42, 52, 62) includes a plasma channel (38). The arc extinguishing skirt (34, 44, 54, 64) interrupts the conduction that occurs in the insulating skirt channel (38) by blocking the plasma arc (3) from conducting current from rail to rail (1a, 1b) at the rear of the projectile (30, 40, 50, 60). The arc extinguishing skirt may be comprised of two plates (36a, 36b) which form a horseshoe wherein the plates are parallel to the rails (1a, b); a chisel-shape design; cross-shaped, or it may be a cylindrical (64). The length of the insulating skirt channel is selected such that there is sufficient plasma in the channel to enable adequate current conduction between the rails (1a, 1b).

Experimental studies of collisional plasma shocks and plasma interpenetration via merging supersonic plasma jets

NASA Astrophysics Data System (ADS)

Hsu, S. C.; Moser, A. L.; Merritt, E. C.; Adams, C. S.

2015-11-01

Over the past 4 years on the Plasma Liner Experiment (PLX) at LANL, we have studied obliquely and head-on-merging supersonic plasma jets of an argon/impurity or hydrogen/impurity mixture. The jets are formed/launched by pulsed-power-driven railguns. In successive experimental campaigns, we characterized the (a) evolution of plasma parameters of a single plasma jet as it propagated up to ~ 1 m away from the railgun nozzle, (b) density profiles and 2D morphology of the stagnation layer and oblique shocks that formed between obliquely merging jets, and (c) collisionless interpenetration transitioning to collisional stagnation between head-on-merging jets. Key plasma diagnostics included a fast-framing CCD camera, an 8-chord visible interferometer, a survey spectrometer, and a photodiode array. This talk summarizes the primary results mentioned above, and highlights analyses of inferred post-shock temperatures based on observations of density gradients that we attribute to shock-layer thickness. We also briefly describe more recent PLX experiments on Rayleigh-Taylor-instability evolution with magnetic and viscous effects, and potential future collisionless shock experiments enabled by low-impurity, higher-velocity plasma jets formed by contoured-gap coaxial guns. Supported by DOE Fusion Energy Sciences and LANL LDRD.

Skirted projectiles for railguns

DOEpatents

Hawke, R.S.; Susoeff, A.R.

1994-01-04

A single skirt projectile (20) having an insulating skirt (22) at its rear, or a dual trailing skirt projectile (30, 40, 50, 60) having an insulating skirt (32, 42, 52, 62) succeeded by an arc extinguishing skirt (34, 44, 54, 64), is accelerated by a railgun accelerator 10 having a pair of parallel conducting rails (1a, 1b) which are separated by insulating wall spacers (11). The insulating skirt (22, 32, 42, 52, 62) includes a plasma channel (38). The arc extinguishing skirt (34, 44, 54, 64) interrupts the conduction that occurs in the insulating skirt channel (38) by blocking the plasma arc (3) from conducting current from rail to rail (1a, 1b) at the rear of the projectile (30, 40, 50, 60). The arc extinguishing skirt may be comprised of two plates (36a, 36b) which form a horseshoe wherein the plates are parallel to the rails (1a, b); a chisel-shape design; cross-shaped, or it may be a cylindrical (64). The length of the insulating skirt channel is selected such that there is sufficient plasma in the channel to enable adequate current conduction between the rails (1a, 1b).

Conduction-coupled Tesla transformer.

PubMed

Reed, J L

2015-03-01

A proof-of-principle Tesla transformer circuit is introduced. The new transformer exhibits the high voltage-high power output signal of shock-excited transformers. The circuit, with specification of proper circuit element values, is capable of obtaining extreme oscillatory voltages. The primary and secondary portions of the circuit communicate solely by conduction. The destructive arcing between the primary and secondary inductors in electromagnetically coupled transformers is ubiquitous. Flashover is eliminated in the new transformer as the high-voltage inductors do not interpenetrate and so do not possess an annular volume of electric field. The inductors are remote from one another. The high voltage secondary inductor is isolated in space, except for a base feed conductor, and obtains earth by its self-capacitance to the surroundings. Governing equations, for the ideal case of no damping, are developed from first principles. Experimental, theoretical, and circuit simulator data are presented for the new transformer. Commercial high-temperature superconductors are discussed as a means to eliminate the counter-intuitive damping due to small primary inductances in both the electromagnetic-coupled and new conduction-coupled transformers.

Study of plasma environments for the integrated Space Station electromagnetic analysis system

NASA Technical Reports Server (NTRS)

Singh, Nagendra

1992-01-01

The final report includes an analysis of various plasma effects on the electromagnetic environment of the Space Station Freedom. Effects of arcing are presented. Concerns of control of arcing by a plasma contactor are highlighted. Generation of waves by contaminant ions are studied and amplitude levels of the waves are estimated. Generation of electromagnetic waves by currents in the structure of the space station, driven by motional EMF, is analyzed and the radiation level is estimated.

Comparison of Commercial Electromagnetic Interface Test Techniques to NASA Electromagnetic Interference Test Techniques

NASA Astrophysics Data System (ADS)

Smith, V.

2000-11-01

This report documents the development of analytical techniques required for interpreting and comparing space systems electromagnetic interference test data with commercial electromagnetic interference test data using NASA Specification SSP 30237A "Space Systems Electromagnetic Emission and Susceptibility Requirements for Electromagnetic Compatibility." The PSpice computer simulation results and the laboratory measurements for the test setups under study compare well. The study results, however, indicate that the transfer function required to translate test results of one setup to another is highly dependent on cables and their actual layout in the test setup. Since cables are equipment specific and are not specified in the test standards, developing a transfer function that would cover all cable types (random, twisted, or coaxial), sizes (gauge number and length), and layouts (distance from the ground plane) is not practical.

Comparison of Commercial Electromagnetic Interface Test Techniques to NASA Electromagnetic Interference Test Techniques

NASA Technical Reports Server (NTRS)

Smith, V.; Minor, J. L. (Technical Monitor)

2000-01-01

This report documents the development of analytical techniques required for interpreting and comparing space systems electromagnetic interference test data with commercial electromagnetic interference test data using NASA Specification SSP 30237A "Space Systems Electromagnetic Emission and Susceptibility Requirements for Electromagnetic Compatibility." The PSpice computer simulation results and the laboratory measurements for the test setups under study compare well. The study results, however, indicate that the transfer function required to translate test results of one setup to another is highly dependent on cables and their actual layout in the test setup. Since cables are equipment specific and are not specified in the test standards, developing a transfer function that would cover all cable types (random, twisted, or coaxial), sizes (gauge number and length), and layouts (distance from the ground plane) is not practical.

Feasibility of cooling the Earth with a cloud of small spacecraft near the inner Lagrange point (L1).

PubMed

Angel, Roger

2006-11-14

If it were to become apparent that dangerous changes in global climate were inevitable, despite greenhouse gas controls, active methods to cool the Earth on an emergency basis might be desirable. The concept considered here is to block 1.8% of the solar flux with a space sunshade orbited near the inner Lagrange point (L1), in-line between the Earth and sun. Following the work of J. Early [Early, JT (1989) J Br Interplanet Soc 42:567-569], transparent material would be used to deflect the sunlight, rather than to absorb it, to minimize the shift in balance out from L1 caused by radiation pressure. Three advances aimed at practical implementation are presented. First is an optical design for a very thin refractive screen with low reflectivity, leading to a total sunshade mass of approximately 20 million tons. Second is a concept aimed at reducing transportation cost to 50 dollars/kg by using electromagnetic acceleration to escape Earth's gravity, followed by ion propulsion. Third is an implementation of the sunshade as a cloud of many spacecraft, autonomously stabilized by modulating solar radiation pressure. These meter-sized "flyers" would be assembled completely before launch, avoiding any need for construction or unfolding in space. They would weigh a gram each, be launched in stacks of 800,000, and remain for a projected lifetime of 50 years within a 100,000-km-long cloud. The concept builds on existing technologies. It seems feasible that it could be developed and deployed in approximately 25 years at a cost of a few trillion dollars, <0.5% of world gross domestic product (GDP) over that time.

Feasibility of cooling the Earth with a cloud of small spacecraft near the inner Lagrange point (L1)

PubMed Central

Angel, Roger

2006-01-01

If it were to become apparent that dangerous changes in global climate were inevitable, despite greenhouse gas controls, active methods to cool the Earth on an emergency basis might be desirable. The concept considered here is to block 1.8% of the solar flux with a space sunshade orbited near the inner Lagrange point (L1), in-line between the Earth and sun. Following the work of J. Early [Early, JT (1989) J Br Interplanet Soc 42:567–569], transparent material would be used to deflect the sunlight, rather than to absorb it, to minimize the shift in balance out from L1 caused by radiation pressure. Three advances aimed at practical implementation are presented. First is an optical design for a very thin refractive screen with low reflectivity, leading to a total sunshade mass of ≈20 million tons. Second is a concept aimed at reducing transportation cost to $50/kg by using electromagnetic acceleration to escape Earth's gravity, followed by ion propulsion. Third is an implementation of the sunshade as a cloud of many spacecraft, autonomously stabilized by modulating solar radiation pressure. These meter-sized “flyers” would be assembled completely before launch, avoiding any need for construction or unfolding in space. They would weigh a gram each, be launched in stacks of 800,000, and remain for a projected lifetime of 50 years within a 100,000-km-long cloud. The concept builds on existing technologies. It seems feasible that it could be developed and deployed in ≈25 years at a cost of a few trillion dollars, <0.5% of world gross domestic product (GDP) over that time. PMID:17085589

Coupling gravity, electromagnetism and space-time for space propulsion breakthroughs

NASA Technical Reports Server (NTRS)

Millis, Marc G.

1994-01-01

spaceflight would be revolutionized if it were possible to propel a spacecraft without rockets using the coupling between gravity, electromagnetism, and space-time (hence called 'space coupling propulsion'). New theories and observations about the properties of space are emerging which offer new approaches to consider this breakthrough possibility. To guide the search, evaluation, and application of these emerging possibilities, a variety of hypothetical space coupling propulsion mechanisms are presented to highlight the issues that would have to be satisfied to enable such breakthroughs. A brief introduction of the emerging opportunities is also presented.

Survival of rock-colonizing organisms after 1.5 years in outer space.

PubMed

Onofri, Silvano; de la Torre, Rosa; de Vera, Jean-Pierre; Ott, Sieglinde; Zucconi, Laura; Selbmann, Laura; Scalzi, Giuliano; Venkateswaran, Kasthuri J; Rabbow, Elke; Sánchez Iñigo, Francisco J; Horneck, Gerda

2012-05-01

Cryptoendolithic microbial communities and epilithic lichens have been considered as appropriate candidates for the scenario of lithopanspermia, which proposes a natural interplanetary exchange of organisms by means of rocks that have been impact ejected from their planet of origin. So far, the hardiness of these terrestrial organisms in the severe and hostile conditions of space has not been tested over extended periods of time. A first long-term (1.5 years) exposure experiment in space was performed with a variety of rock-colonizing eukaryotic organisms at the International Space Station on board the European EXPOSE-E facility. Organisms were selected that are especially adapted to cope with the environmental extremes of their natural habitats. It was found that some-but not all-of those most robust microbial communities from extremely hostile regions on Earth are also partially resistant to the even more hostile environment of outer space, including high vacuum, temperature fluctuation, the full spectrum of extraterrestrial solar electromagnetic radiation, and cosmic ionizing radiation. Although the reported experimental period of 1.5 years in space is not comparable with the time spans of thousands or millions of years believed to be required for lithopanspermia, our data provide first evidence of the differential hardiness of cryptoendolithic communities in space.

Gravity Fields Generation In The Universe By The Large Range of Scales Convection Systems In Planets, Stars, Black Holes and Galaxies Based On The "Convection Bang Hypothesis"

NASA Astrophysics Data System (ADS)

Gholibeigian, H.; Amirshahkarami, A.; Gholibeigian, K.

2015-12-01

In our vision it is believed that the Big Bang was Convection Bang (CB). When CB occurred, a gigantic large-scale forced convection system (LFCS) began to create space-time including gravitons and gluons in more than light speed. Then, simultaneously by a swirling wild wind, created inflation process including many quantum convection loops (QCL) in locations which had more density of temperature and energetic particles like gravitons. QCL including fundamental particles, grew and formed black holes (BHs) as the core of galaxies. LFCSs of heat and mass in planets, stars, BHs and galaxies generate gravity and electromagnetic fields and change the properties of matter and space-time around the systems. Mechanism: Samples: 1- Due to gravity fields of Sun and Moon, Earth's inner core is dislocated toward them and rotates around the Earth's center per day and generates LFCSs, Gholibeigian [AGU, 2012]. 2- Dislocated Sun's core due to gravity fields of planets/ Jupiter, rotates around the Sun's center per 25-35 days and generates LFCSs, Gholibeigian [EGU, 2014]. 3- If a planet/star falls into a BH, what happens? It means, its dislocated core rotates around its center in less than light speed and generates very fast LFCS and friction, while it is rotating/melting around/inward the center of BH. Observable Factors: 1- There is not logical relation between surface gravity fields of planets/Sun and their masses (general relativity); see Planetary Fact Sheet/Ratio to Earth Values-NASA: Earth: mass/gravity =1/1, Jupiter=317.8/2.36, Neptune=17.1/1.12, Saturn=95.2/0.916, Moon=0.0128/0.166, Sun=333000/28. 2- Convective systems in thunderstorms help bring ozone down to Earth [Brian-Kahn]. 3- In 12 surveyed BHs, produced gravity force & magnetic field strength were matched (unique LFCS source) [PhysOrg - June 4, 2014]. Justification: After BB/CB, gravitons were created without any other masses and curvature of space-time (general relativity), but by primary gigantic convection process.

Prompt Recovery and Enhancement of the Earth's Outer Radiation Belt due to Relativistic Electron Injections

NASA Astrophysics Data System (ADS)

Tang, C. L.; Zhang, J.; Reeves, G. D.; Baker, D. N.; Spence, H. E.; Funsten, H. O.; Blake, J. B.

2015-12-01

We present multipoint observations (RBSP, GEOS and THEMIS) of the substorm electron injections during the substorm event on 16 August 2013. RBSP-A detected the MeV electron phase space density increased by an order of magnitude in about one hour at L* > 5.0. At L* = 4.4, the injected MeV electrons were also detected. It is suggested that the magnetic field dipolarization associated with the substorm injections alone can explain that the prompt recovery and enhancements of the relativistic electron (~ MeV) fluxes in the outer radiation belt. The observations of THEMIS-A also first presented that the near-Earth magnetotail at substorm onset is important in the MeV electron injection event: the enhanced fluxes of ~200 keV electrons are the source population and intense electromagnetic pulses are the driving source of MeV injected electrons. The pulse model is used to explain the dispersionless MeV injected electrons in the outer radiation belt observed by GEOS-13 and RBSP-A.

Space Science for the 21st Century. Strategic Plan for 1995-2000

NASA Technical Reports Server (NTRS)

1994-01-01

This publication is one of three volumes in 'Space Science for the 21st Century', the Office of Space Science Strategic plan for 1995-2000. The other two volumes are the recently released Integrated Technology Strategy and the Education Plan, which is in preparation at this publication date. The Science Plan was developed by the Office of Space Science (OSS) in partnership with the Space Science Advisory Committee. The mission of the OSS is to seek answers to fundamental questions about: the galaxy and the universe; the connection between the Sun, Earth, and Heliosphere; the origin and evolution of planetary systems; and the origin and distribution of life in the universe. The strategy to answer these questions includes completing the means to survey the universe across the entire electromagnetic spectrum; completing the survey of cosmic rays through their highest energies, and of interstellar gas; carrying out a basic new test of the Theory of General Relativity; completing development of the means to understand the mechanisms of solar variability and its effects on Earth; completing the first exploration of the inner and outer frontiers of the heliosphere; determining the plasma environments of the solar system planets and how those environments are affected by solar activity; completing development of the means to finish the reconnaissance of the entire solar system from the Sun to Pluto; beginning the comprehensive search for other planets around other stars; resuming surface exploration of solar system bodies to understand the origin and evolution of the Sun's planetary system; continuing the study of biogenic compounds and their evolution in the universe; and searching for indicators of past and present conditions conducive to life.

Seismo-electromagnetic phenomena in the western part of the Eurasia-Nubia plate boundary

NASA Astrophysics Data System (ADS)

Gonçalves da Silva, Hugo; Bezzeghoud, Mourad; Biagi, Pier; Namorado Rosa, Rui; Salgueiro da Silva, Manuel; Caldeira, Bento; Heitor Reis, Artur; Borges, José Fernando; Tlemçani, Mouhaydine; Manso, Marco

2010-05-01

This paper presents a future research plan that aims to monitor Seismo-electromagnetic (SEM) phenomena in the western part of the Eurasia-Nubia plate boundary (WENP). This region has a significant tectonic activity [1] combined with relatively low electromagnetic noise levels and for that reason presents the possibility to perform high quality SEM measurements. Further, it is known that low-frequency [ultra (ULF), very (VLF), and low-frequencies (LF)] electromagnetic (EM) waves produce more convincing earthquake precursors (compared to higher frequencies) because of less contamination, large skin depth, and low attenuation [2]. Thus, two SEM effects will be considered: ULF electromagnetic field emissions [3], and VLF/LF radio broadcastings [4]. With respect to the ULF measurements, as a start, three ULF sensors are planned to be installed in the South of Iberian Peninsula supported by the existing networks of seismic research stations. Subsequent development of this initial plan could result in the implementation of a lager ULF monitoring network not only in the Iberian Peninsula, but also in the rest of Europe. Possible integration in the SEGMA array is now under consideration. Another perspective is to use a portable station to track seismic events. Regarding the VLF/LF radio broadcastings, a receiver is planned to be mounted in University of Évora. Radio signals from up to 10 transmitters (in these bands) of interest to study the seismic activity in the WENP region will be monitored. Actually, the radio path from the transmitter to the receiver should cross the epicentral area, therefore two possible transmitters are the ones installed in Monaco (France) and Sicily (Italy). Furthermore, the system will integrate the INFREP network and in this context it will not be restricted to WENP region. With the development of these research plans we aim to collect novel SEM data emerging from the seismic activity in the WENP region. We expect to address the time variations of EM properties of the crust/plate in relation with the strain field, and in space in relation with composition and temperature and stress fields. Further, the interplay between atmospheric (and solar) perturbations with crust perturbations will be monitored, to observe geomagnetic perturbations at different locations. Our study will be focused in the analyses of low magnitude earthquakes with M =< 4, these events are frequent in the WENP region, but have been almost completely disregarded in literature [5,6]. [1] J. Borges, A. J. S. Fitas, M. Bezzeghoud, and P. Teves-Costa, Tectonophysics 337, 373 (2001). [2] V. Chauhan, O.P. Singh, V. Kushwah, V. Singh, B. Singh, Journal of Geodynamics 48, 68 (2009). [3] L. Telesca, V. Lapenna, M. Macchiato, and K. Hattori, Earth and Planet. Science Lett. 268, 219 (2008). [4] P. F. Biagi, L. Castellana, T. Maggipinto, D. Loiacono, L. Schiavulli, T. Ligonzo, M. Fiore, E. Suciu, and A. Ermini, Nat. Hazards Earth Syst. Sci. 9, 1551 (2009). [5] A. Rozhnoi , M.S. Solovieva, O.A. Molchanov, and M. Hayakawa, Phys. and Chem. of the Earth 29, 589-598 (2004). [6] K. Hattori, I. Takahashi, C. Yoshino, N. Isezaki, H. Iwasaki, M. Harada, K. Kawabata, E. Kopytenko, Y. Kopytenko, P. Maltsev, V. Korepanov, O. Molchanov, M. Hayakawa, Y. Noda, T. Nagao, S. Uyeda, Physics and Chemistry of the Earth 29, 481-494 (2004).

Hypersonic MHD Propulsion System Integration for the Mercury Lightcraft

NASA Astrophysics Data System (ADS)

Myrabo, L. N.; Rosa, R. J.

2004-03-01

Introduced herein are the design, systems integration, and performance analysis of an exotic magnetohydrodynamic (MHD) slipstream accelerator engine for a single-occupant ``Mercury'' lightcraft. This ultra-energetic, laser-boosted vehicle is designed to ride a `tractor beam' into space, transmitted from a future orbital network of satellite solar power stations. The lightcraft's airbreathing combined-cycle engine employs a rotary pulsed detonation thruster mode for lift-off & landing, and an MHD slipstream accelerator mode at hypersonic speeds. The latter engine transforms the transatmospheric acceleration path into a virtual electromagnetic `mass-driver' channel; the hypersonic momentum exchange process (with the atmosphere) enables engine specific impulses in the range of 6000 to 16,000 seconds, and propellant mass fractions as low as 10%. The single-stage-to-orbit, highly reusable lightcraft can accelerate at 3 Gs into low Earth orbit with its throttle just barely beyond `idle' power, or virtually `disappear' at 30 G's and beyond. The objective of this advanced lightcraft design is to lay the technological foundations for a safe, very low cost (e.g., 1000X below chemical rockets) air and space transportation for human life in the mid-21st Century - a system that will be completely `green' and independent of Earth's limited fossil fuel reserves.

Experimental characterization of a transition from collisionless to collisional interaction between head-on-merging supersonic plasma jets a)

DOE PAGES

Moser, Auna L.; Hsu, Scott C.

2015-05-01

We present results from experiments on the head-on merging of two supersonic plasma jets in an initially collisionless regime for the counter-streaming ions [A. L. Moser & S. C. Hsu, Phys. Plasmas, submitted (2014)]. The plasma jets are of either an argon/impurity or hydrogen/impurity mixture and are produced by pulsed-power-driven railguns. Based on time- and space-resolved fast-imaging, multi-chord interferometry, and survey-spectroscopy measurements of the overlapping region between the merging jets, we observe that the jets initially interpenetrate, consistent with calculated inter-jet ion collision lengths, which are long. As the jets interpenetrate, a rising mean-charge state causes a rapid decrease inmore » the inter-jet ion collision length. Finally, the interaction becomes collisional and the jets stagnate, eventually producing structures consistent with collisional shocks. These experimental observations can aid in the validation of plasma collisionality and ionization models for plasmas with complex equations of state.« less

Experimental characterization of a transition from collisionless to collisional interaction between head-on-merging supersonic plasma jets a)

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

Moser, Auna L.; Hsu, Scott C.

We present results from experiments on the head-on merging of two supersonic plasma jets in an initially collisionless regime for the counter-streaming ions [A. L. Moser & S. C. Hsu, Phys. Plasmas, submitted (2014)]. The plasma jets are of either an argon/impurity or hydrogen/impurity mixture and are produced by pulsed-power-driven railguns. Based on time- and space-resolved fast-imaging, multi-chord interferometry, and survey-spectroscopy measurements of the overlapping region between the merging jets, we observe that the jets initially interpenetrate, consistent with calculated inter-jet ion collision lengths, which are long. As the jets interpenetrate, a rising mean-charge state causes a rapid decrease inmore » the inter-jet ion collision length. Finally, the interaction becomes collisional and the jets stagnate, eventually producing structures consistent with collisional shocks. These experimental observations can aid in the validation of plasma collisionality and ionization models for plasmas with complex equations of state.« less

Electromagnetic Propulsion

NASA Technical Reports Server (NTRS)

Schafer, Charles

2000-01-01

The design and development of an Electromagnetic Propulsion is discussed. Specific Electromagnetic Propulsion Topics discussed include: (1) Technology for Pulse Inductive Thruster (PIT), to design, develop, and test of a multirepetition rate pulsed inductive thruster, Solid-State Switch Technology, and Pulse Driver Network and Architecture; (2) Flight Weight Magnet Survey, to determine/develop light weight high performance magnetic materials for potential application Advanced Space Flight Systems as these systems develop; and (3) Magnetic Flux Compression, to enable rapid/robust/reliable omni-planetary space transportation within realistic development and operational costs constraints.

X-ray and gamma ray astronomy detectors

NASA Technical Reports Server (NTRS)

Decher, Rudolf; Ramsey, Brian D.; Austin, Robert

1994-01-01

X-ray and gamma ray astronomy was made possible by the advent of space flight. Discovery and early observations of celestial x-rays and gamma rays, dating back almost 40 years, were first done with high altitude rockets, followed by Earth-orbiting satellites> once it became possible to carry detectors above the Earth's atmosphere, a new view of the universe in the high-energy part of the electromagnetic spectrum evolved. Many of the detector concepts used for x-ray and gamma ray astronomy were derived from radiation measuring instruments used in atomic physics, nuclear physics, and other fields. However, these instruments, when used in x-ray and gamma ray astronomy, have to meet unique and demanding requirements related to their operation in space and the need to detect and measure extremely weak radiation fluxes from celestial x-ray and gamma ray sources. Their design for x-ray and gamma ray astronomy has, therefore, become a rather specialized and rapidly advancing field in which improved sensitivity, higher energy and spatial resolution, wider spectral coverage, and enhanced imaging capabilities are all sought. This text is intended as an introduction to x-ray and gamma ray astronomy instruments. It provides an overview of detector design and technology and is aimed at scientists, engineers, and technical personnel and managers associated with this field. The discussion is limited to basic principles and design concepts and provides examples of applications in past, present, and future space flight missions.

The basic thermodynamics of Earth's radiation budget

NASA Astrophysics Data System (ADS)

Ward, Peter L.

2015-04-01

The microscopic bonds that hold matter together oscillate about a potential energy minimum between attractive and repulsive electrostatic forces, giving rise to macroscopic temperature. When a body of matter reaches thermal equilibrium, the spectrum of frequencies and associated amplitudes of oscillation on the body's surface are described by Planck's empirical law, which shows that heating matter increases the amplitude of these oscillations at all frequencies and shifts the peak frequency to a higher value. The oscillating motion of charge on the surface of matter induces an electromagnetic field in air or space containing the same frequencies (colors) and amplitudes (brightness) flowing away from the surface just as a radio station transmits its frequency and amplitude. Numerous frequencies coexist in an electromagnetic field over a broad spectral range, but each frequency does not interact with any other frequencies and does not change as it propagates over galactic distances except for Doppler effects. Amplitudes (intensities, brightness), on the other hand, decrease by one over the square of the distance traveled as they spread out over the surface of an expanding sphere. Planck (1900) showed that in air and space radiant (thermal) energy at each frequency is equal to the frequency times a constant (E=hν), an expression used widely in photochemistry to designate the thermal energy required to cause a photochemical reaction. High-frequency ultraviolet radiation causes sunburn; lower frequency visible radiation powers photosynthesis; much lower frequency infrared radiation cannot cause either, no matter how large the amplitude or the amount. While many frequencies coexist in air or space, neither frequencies nor energies interact or are additive until in the presence of matter. According to E=hν, the solar, ultraviolet thermal energy that reaches Earth when ozone is depleted is at least 48 times more energetic (hotter) than infrared energy absorbed by greenhouse gases. There simply is not enough thermal energy absorbed by greenhouse gases to have a major effect on global warming. Computer programs used to quantify greenhouse-gas theory overestimate infrared energies because they assume that thermal energy travels in space as waves, for which energy is a function of amplitude squared, and that energies are additive over bandwidth, both properties that are very different from the observed behavior of radiation in the atmosphere. Heat only flows from hot to cold; it cannot flow from a colder layer in the atmosphere to a warmer Earth, as assumed in many radiation budgets (e.g. Wild et al., 2013); you cannot get warmer by standing next to a cold stove. According to Planck's Law, radiation from a body of matter does not have high enough frequencies or amplitudes to warm the same body, as is assumed by greenhouse-gas theory. Warming radiation must come from a warmer body. Detailed observations of global warming, including the recent hiatus, are explained much more directly and clearly by ozone depletion theory, where less ozone in the stratosphere allows more high-energy, solar ultraviolet radiation to reach Earth, cooling the stratosphere, warming the oceans. More details at ozonedepletiontheory.info plus a video at tinyurl.com/ozone-depletion-theory.

[The influence of electromagnetic fields on flora and fauna].

PubMed

Rochalska, Małgorzata

2009-01-01

This paper presents the influence of natural and artificial electromagnetic fields (EMF) on fauna and flora. The mechanisms of Earth's magnetic field detection and the use of this skill by migratory animals to faultlessly reach the destination of their travel are discussed, as well as the positive effects of electric and magnetic fields on plants relative to their physiology, yielding and health. EMF influence on social insects and animal organisms, including possible DNA damages and DNA repair systems, is presented. The influence of high frequency electromagnetic fields on birds nesting is also discussed.

CRRES combined radiation and release effects satellite program

NASA Technical Reports Server (NTRS)

Giles, B. L. (Compiler); Mccook, M. A. (Compiler); Mccook, M. W. (Compiler); Miller, G. P. (Compiler)

1995-01-01

The various regions of the magnetosphere-ionosphere system are coupled by flows of charged particle beams and electromagnetic waves. This coupling gives rise to processes that affect both technical and non-technical aspects of life on Earth. The CRRES Program sponsored experiments which were designed to produce controlled and known input to the space environment and the effects were measured with arrays of diagnostic instruments. Large amounts of material were used to modify and perturb the environment in a controlled manner, and response to this was studied. The CRRES and PEGSAT satellites were dual-mission spacecraft with a NASA mission to perform active chemical-release experiments, grouped into categories of tracer, modification, and simulation experiments. Two sounding rocket chemical release campaigns completed the study.

Detection of electromagnetic radiation using nonlinear materials

DOEpatents

Hwang, Harold Y.; Liu, Mengkun; Averitt, Richard D.; Nelson, Keith A.; Sternbach, Aaron; Fan, Kebin

2016-06-14

An apparatus for detecting electromagnetic radiation within a target frequency range is provided. The apparatus includes a substrate and one or more resonator structures disposed on the substrate. The substrate can be a dielectric or semiconductor material. Each of the one or more resonator structures has at least one dimension that is less than the wavelength of target electromagnetic radiation within the target frequency range, and each of the resonator structures includes at least two conductive structures separated by a spacing. Charge carriers are induced in the substrate near the spacing when the resonator structures are exposed to the target electromagnetic radiation. A measure of the change in conductivity of the substrate due to the induced charge carriers provides an indication of the presence of the target electromagnetic radiation.

Feasibility study of a swept frequency electromagnetic probe (SWEEP) using inductive coupling for the determination of subsurface conductivity of the earth and water prospecting in arid regions

NASA Technical Reports Server (NTRS)

Latorraca, G. A.; Bannister, L. H.

1974-01-01

Techniques developed for electromagnetic probing of the lunar interior, and techniques developed for the generation of high power audio frequencies were combined to make practical a magnetic inductive coupling system for the rapid measurement of ground conductivity profiles which are helpful when prospecting for the presence and quality of subsurface water. A system which involves the measurement of the direction, intensity, and time phase of the magnetic field observed near the surface of the earth at a distance from a horizontal coil energized so as to create a field that penetrates the earth was designed and studied to deduce the conductivity and stratification of the subsurface. Theoretical studies and a rudimentary experiment in an arid region showed that the approach is conceptually valid and that this geophysical prospecting technique can be developed for the economical exploration of subterranean water resources.

Electromagnetic panel deployment and retraction using the geomagnetic field in LEO satellite missions

NASA Astrophysics Data System (ADS)

Inamori, Takaya; Sugawara, Yoshiki; Satou, Yasutaka

2015-12-01

Increasingly, spacecraft are installed with large-area structures that are extended and deployed post-launch. These extensible structures have been applied in several missions for power generation, thermal radiation, and solar propulsion. Here, we propose a deployment and retraction method using the electromagnetic force generated when the geomagnetic field interacts with electric current flowing on extensible panels. The panels are installed on a satellite in low Earth orbit. Specifically, electrical wires placed on the extensible panels generate magnetic moments, which interfere with the geomagnetic field. The resulting repulsive and retraction forces enable panel deployment and retraction. In the proposed method, a satellite realizes structural deployment using simple electrical wires. Furthermore, the satellite can achieve not only deployment but also retraction for avoiding damage from space debris and for agile attitude maneuvers. Moreover, because the proposed method realizes quasi-static deployment and the retraction of panels by electromagnetic forces, low impulsive force is exerted on fragile panels. The electrical wires can also be used to detect the panel deployment and retraction and generate a large magnetic moment for attitude control. The proposed method was assessed in numerical simulations based on multibody dynamics. Simulation results shows that a small cubic satellite with a wire current of 25 AT deployed 4 panels (20 cm × 20 cm) in 500 s and retracted 4 panels in 100 s.

The earthshine s spectra

NASA Astrophysics Data System (ADS)

Montanes Rodriguez, P.; Palle, E.; Goode, P.; Koonin, S.; Hickey, J.; Qiu, J.; Yurchysyn, V.

The Earthshine project, was run by California Institute of Technology (Caltech) between 1993 and 1995. Since 1998, it has been a collaborative effort between Caltech and Big Bear Solar Observatory (BBSO)/New Jersey Institute of Technology (NJIT). Our primary goal is the precise determination of a global and absolutely calibrated Earth's albedo and its synoptic, seasonal, and annual variability; as well as the measurement and investigation of the resolved reflected spectrum of the integrated Earth in the infrared region. The absorption in the infrared region, mainly due to rotational and vibrational transitions of the molecules, show the absorption bands of various telluric and solar components allowing the analysis of the Earth's spectrum such as it would be observed from the outer space. In this paper we present preliminary results of spectroscopic observations, made at Palomar Observatory with the 60-inch telescope's echelle spectrograph. They targeted the visible and near infrared region of the electromagnetic spectrum, and were performed in the spectral range (< 1μm) of the bands of Oxygen A, Oxygen B, water and Hydrogen alpha (H). The first three are typically terrestrial molecular bands. The fourth line, H, is a solar line, used mainly for spectral calibration.

AAFE man-made noise experiment project. Volume 2: Project and experiment discussions

NASA Technical Reports Server (NTRS)

1974-01-01

An experiment for the acquisition and processing of man-made noise interference data on earth orbital altitudes is discussed. The objectives of the project are to confirm the results of analytical studies concerning radio frequency man-made noise in space. It is stated that the measurements of the amounts and types of noise in frequency bands of interest could allow the allocation and utilization of frequencies to be optimized and would also contribute to the engineering objective of optimizing flight receiving systems. A second objective of the project was to design and fabricate a noise measuring receiver which would demonstrate the feasibility of the experiment design under the project. The procedures for acquiring and processing the electromagnetic radiation data are discussed.

Preliminary Study of 2-D Time Domain Electromagnetic (TDEM) Modeling to Analyze Subsurface Resistivity Distribution and its Application to the Geothermal Systems

NASA Astrophysics Data System (ADS)

Aji Hapsoro, Cahyo; Purqon, Acep; Srigutomo, Wahyu

2017-07-01

2-D Time Domain Electromagnetic (TDEM) has been successfully conducted to illustrate the value of Electric field distribution under the Earth surface. Electric field compared by magnetic field is used to analyze resistivity and resistivity is one of physical properties which very important to determine the reservoir potential area of geothermal systems as one of renewable energy. In this modeling we used Time Domain Electromagnetic method because it can solve EM field interaction problem with complex geometry and to analyze transient problems. TDEM methods used to model the value of electric and magnetic fields as a function of the time combined with the function of distance and depth. The result of this modeling is Electric field intensity value which is capable to describe the structure of the Earth’s subsurface. The result of this modeling can be applied to describe the Earths subsurface resistivity values to determine the reservoir potential of geothermal systems.

Dust That's Worth Keeping

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

Hazi, A

2006-01-25

Images taken of interstellar space often display a colorful canvas of portions of the electromagnetic spectrum. Dispersed throughout the images are interstellar clouds of dust and gas--remnants ejected from stars and supernovae over billions and billions of years. For more than 40 years, astronomers have observed that interstellar dust exhibits a consistent effect at a spectral wavelength of 2,175 angstroms, the equivalent of 5.7 electronvolts in energy on the electromagnetic spectrum. At this wavelength, light from stars is absorbed by dust in the interstellar medium, blocking the stars light from reaching Earth. The 2,175-angstrom feature, which looks like a bumpmore » on spectra, is the strongest ultraviolet-visible light spectral signature of interstellar dust and is visible along nearly every observational line of sight. Scientists have sought to solve the mystery of what causes the 2,175-angstrom feature by reproducing the effect in the laboratory. They speculated a number of possibilities, including fullerenes (buckyballs), nanodiamonds, and even interstellar organisms. However, none of these materials fits the data for the unique spectral feature. Limitations in the energy and spatial resolution achievable with electron microscopes and ion microprobes--the two main instruments used to study samples of dust--have also prevented scientists from finding the answer. A collaborative effort led by Livermore physicist John Bradley and funded by the National Aeronautics and Space Administration (NASA) has used a new-generation transmission electron microscope (TEM) and nanoscale ion microprobe to unlock the mystery. The Livermore group includes physicists Zu Rong Dai, Ian Hutcheon, Peter Weber, and Sasa Bajt and postdoctoral researchers Hope Ishii, Giles Graham, and Julie Smith. They collaborated with the University of California at Davis (UCD), Lawrence Berkeley National Laboratory, Washington University's Laboratory for Space Sciences in St. Louis, and NASA's Ames Research Center for their discovery. The team analyzed micrometer-size interplanetary dust particles (IDPs), each about one-tenth the diameter of a human hair. Within the particles, they found carriers of the 2,175-angstrom feature: organic carbon mixed with amorphous silicates (glass with embedded metals and sulfides, GEMS), two of the most common materials in interstellar space. Ishii says, ''Organic carbon and amorphous silicates are abundant in interstellar dust clouds, and abundant carriers are needed to account for the frequent astronomical observation of the 2,175-angstrom feature. It makes sense that this ubiquitous feature would come from common materials in interstellar space''. The group's results increase scientific understanding of the starting materials for the formation of the Sun, solar system, and life on Earth.« less

Dust That's Worth Keeping

NASA Technical Reports Server (NTRS)

Hazi, A.

2006-01-01

Images taken of interstellar space often display a colorful canvas of portions of the electromagnetic spectrum. Dispersed throughout the images are interstellar clouds of dust and gas--remnants ejected from stars and supernovae over billions and billions of years. For more than 40 years, astronomers have observed that interstellar dust exhibits a consistent effect at a spectral wavelength of 2,175 angstroms, the equivalent of 5.7 electronvolts in energy on the electromagnetic spectrum. At this wavelength, light from stars is absorbed by dust in the interstellar medium, blocking the stars light from reaching Earth. The 2,175-angstrom feature, which looks like a bump on spectra, is the strongest ultraviolet-visible light spectral signature of interstellar dust and is visible along nearly every observational line of sight. Scientists have sought to solve the mystery of what causes the 2,175-angstrom feature by reproducing the effect in the laboratory. They speculated a number of possibilities, including fullerenes (buckyballs), nanodiamonds, and even interstellar organisms. However, none of these materials fits the data for the unique spectral feature. Limitations in the energy and spatial resolution achievable with electron microscopes and ion microprobes--the two main instruments used to study samples of dust--have also prevented scientists from finding the answer. A collaborative effort led by Livermore physicist John Bradley and funded by the National Aeronautics and Space Administration (NASA) has used a new-generation transmission electron microscope (TEM) and nanoscale ion microprobe to unlock the mystery. The Livermore group includes physicists Zu Rong Dai, Ian Hutcheon, Peter Weber, and Sasa Bajt and postdoctoral researchers Hope Ishii, Giles Graham, and Julie Smith. They collaborated with the University of California at Davis (UCD), Lawrence Berkeley National Laboratory, Washington University's Laboratory for Space Sciences in St. Louis, and NASA's Ames Research Center for their discovery. The team analyzed micrometer-size interplanetary dust particles (IDPs), each about one-tenth the diameter of a human hair. Within the particles, they found carriers of the 2,175-angstrom feature: organic carbon mixed with amorphous silicates (glass with embedded metals and sulfides, GEMS), two of the most common materials in interstellar space. Ishii says, 'Organic carbon and amorphous silicates are abundant in interstellar dust clouds, and abundant carriers are needed to account for the frequent astronomical observation of the 2,175-angstrom feature. It makes sense that this ubiquitous feature would come from common materials in interstellar space'. The group's results increase scientific understanding of the starting materials for the formation of the Sun, solar system, and life on Earth.

Electromagnetic containerless processing requirements and recommended facility concept and capabilities for space lab

NASA Technical Reports Server (NTRS)

Frost, R. T.; Bloom, H. L.; Napaluch, L. J.; Stockhoff, E. H.; Wouch, G.

1974-01-01

Containerless melting, reaction, and solidification experiments and processes which potentially can lead to new understanding of material science and production of new or improved materials in the weightless space environment are reviewed in terms of planning for spacelab. Most of the experiments and processes discussed are amenable to the employment of electromagnetic position control and electromagnetic induction or electron beam heating and melting. The spectrum of relevant properties of materials, which determine requirements for a space laboratory electromagnetic containerless processing facility are reviewed. Appropriate distributions and associated coil structures are analyzed and compared on the basis of efficiency, for providing the functions of position sensing, control, and induction heating. Several coil systems are found capable of providing these functions. Exchangeable modular coils in appropriate sizes are recommended to achieve the maximum power efficiencies, for a wide range of specimen sizes and resistivities, in order to conserve total facility power.

International Symposium on Electromagnetic Compatibility, 25th, Arlington, VA, August 23-25, 1983, Symposium Record

NASA Astrophysics Data System (ADS)

Subjects related to electromagnetic compatibility (EMC) analysis are discussed, taking into account forcing terms of line equations for externally excited transmission lines, E-fields over ground, electromagnetic near fields as a function of electrical size, a program for experimental verification of EMC analysis models, random susceptability of an IC 7400 TTL NAND gate, and a comparison of IEMCAP and SEMCAP. Other topics explored are concerned with EMC measurements, spectrum management, the electromagnetic pulse (EMP), a Navy EMC program, measurement systems, filters, EMC design, electromagnetic vulnerability (EMV) assessment of weapon systems, FCC rules and regulations, shielding, and electromagnetic interference (EMI) in communication systems. Attention is also given to nonsinusoidal functions in radar and communications, transients/electrostatic discharge, open field testing, cables and connectors, interference effects of induced and conducted earth current at dc and ELF, test cells, and cable coupling.

Harmonic Fluxes and Electromagnetic Forces of Concentric Winding Brushless Permanent Magnet Motor

NASA Astrophysics Data System (ADS)

Ishibashi, Fuminori; Takemasa, Ryo; Matsushita, Makoto; Nishizawa, Takashi; Noda, Shinichi

Brushless permanent magnet motors have been widely used in home applications and industrial fields. These days, high efficiency and low noise motors are demanded from the view point of environment. Electromagnetic noise and iron loss of the motor are produced by the harmonic fluxes and electromagnetic forces. However, order and space pattern of these have not been discussed in detail. In this paper, fluxes, electromagnetic forces and magneto-motive forces of brushless permanent magnet motors with concentric winding were analyzed analytically, experimentally and numerically. Time harmonic fluxes and time electromagnetic forces in the air gap were measured by search coils on the inner surface of the stator teeth and analyzed by FEM. Space pattern of time harmonic fluxes and time electromagnetic forces were worked out with experiments and FEM. Magneto motive forces due to concentric winding were analyzed with equations and checked by FEM.

Propulsion Systems Integration for a `Tractor Beam' Mercury Lightcraft: Liftoff Engine

NASA Astrophysics Data System (ADS)

Myrabo, L. N.

2003-05-01

Described herein is the concept and propulsion systems integration for a revolutionary beam-propelled shuttle called the ``Mercury'' lightcraft - emphasizing the liftoff engine mode. This one-person, ultra-energetic vehicle is designed to ride `tractor beams' into space, transmitted from a future network of satellite solar power stations. The objective is to create a safe, very low cost (e.g., 1000X below chemical rockets) space transportation system for human life, one that is completely `green' and independent of Earth's limited fossil fuel reserves. The lightcraft's airbreathing combined-cycle engine operates in a rotary pulsed detonation mode PDE for lift-offs and landings; at hypersonic speeds it transitions into a magnetohydrodynamic (MHD) slipstream accelerator mode. For the latter, the transatmospheric flight path is momentarily transformed into an extremely long, electromagnetic ``mass-driver'' channel with an effective `fuel' specific impulse in the range of 6000 to 16,000 seconds. These future single-stage-to-orbit, highly-reusuable vehicles will ride ``Highways of Light,'' accelerating at 3 Gs into space, with their throttles just barely beyond `idle' power.

Analysis of electromagnetic interference from power system processing and transmission components for Space Station Freedom

NASA Technical Reports Server (NTRS)

Barber, Peter W.; Demerdash, Nabeel A. O.; Wang, R.; Hurysz, B.; Luo, Z.

1991-01-01

The goal is to analyze the potential effects of electromagnetic interference (EMI) originating from power system processing and transmission components for Space Station Freedom.The approach consists of four steps: (1) develop analytical tools (models and computer programs); (2) conduct parameterization studies; (3) predict the global space station EMI environment; and (4) provide a basis for modification of EMI standards.

Magnetic Earth Ionosphere Resonant Frequencies (NASA-MEIRF Project)

NASA Technical Reports Server (NTRS)

1994-01-01

During this current reporting period, the project has focused on completing Phase 1 of the field monitoring work and documenting research results. Highlights of these efforts include presentations of papers at the annual joint meeting of the American Physical Society/American Association of Physics Teachers, April 18-22, 1994, in Crystal City, Virginia, and at the International Space, Time, and Gravitation Conference and Etoiles de L'Ecole Polytechnique Symposium, May 23-28, 1994, in St. Petersburg, Russia. Field measurements of the background ultra low frequency (ULF) electromagnetic spectrum in the New Mexico and Texas regions show interesting differences. Included are papers entitled 'Triplet Solution of the Twin Paradox' and 'Classical Electron Mass and Fields, Part 3.'

Electromagnetic compatibility test report for the tethered satellite data acquisition and control assembly

NASA Astrophysics Data System (ADS)

Hoskins, Douglas; Snead, Robert

1988-05-01

This report details the results of an electromagnetic compatibility test on the SCI Systems Data Acquisition and Control Assembly (DACA). This assembly is an electronic processor which controls the central communication link from the Tethered Satellite System (TSS) to the Space Transportation System Orbiter Space Shuttle.

Asymptotic symmetries and electromagnetic memory

NASA Astrophysics Data System (ADS)

Pasterski, Sabrina

2017-09-01

Recent investigations into asymptotic symmetries of gauge theory and gravity have illuminated connections between gauge field zero-mode sectors, the corresponding soft factors, and their classically observable counterparts — so called "memories". Namely, low frequency emissions in momentum space correspond to long time integrations of the corre-sponding radiation in position space. Memory effect observables constructed in this manner are non-vanishing in typical scattering processes, which has implications for the asymptotic symmetry group. Here we complete this triad for the case of large U(1) gauge symmetries at null infinity. In particular, we show that the previously studied electromagnetic memory effect, whereby the passage of electromagnetic radiation produces a net velocity kick for test charges in a distant detector, is the position space observable corresponding to th Weinberg soft photon pole in momentum space scattering amplitudes.

47 CFR 25.222 - Blanket Licensing provisions for Earth Stations on Vessels (ESVs) receiving in the 10.95-11.2 GHz...

Code of Federal Regulations, 2014 CFR

2014-10-01

... on Vessels (ESVs) receiving in the 10.95-11.2 GHz (space-to-Earth), 11.45-11.7 GHz (space-to-Earth), 11.7-12.2 GHz (space-to-Earth) bands and transmitting in the 14.0-14.5 GHz (Earth-to-space) band... the 10.95-11.2 GHz (space-to-Earth), 11.45-11.7 GHz (space-to-Earth), 11.7-12.2 GHz (space-to-Earth...

Gold Sample Heating within the TEMPUS Electromagnetic Levitation Furnace

NASA Technical Reports Server (NTRS)

2003-01-01

A gold sample is heated by the TEMPUS electromagnetic levitation furnace on STS-94, 1997, MET:10/09:20 (approximate). The sequence shows the sample being positioned electromagnetically and starting to be heated to melting. TEMPUS (stands for Tiegelfreies Elektromagnetisches Prozessiere unter Schwerelosigkeit (containerless electromagnetic processing under weightlessness). It was developed by the German Space Agency (DARA) for flight aboard Spacelab. The DARA project scientist was Igon Egry. The experiment was part of the space research investigations conducted during the Microgravity Science Laboratory-1R mission (STS-94, July 1-17 1997). DARA and NASA are exploring the possibility of flying an advanced version of TEMPUS on the International Space Station. (460KB, 14-second MPEG, screen 160 x 120 pixels; downlinked video, higher quality not available) A still JPG composite of this movie is available at http://mix.msfc.nasa.gov/ABSTRACTS/MSFC-0300190.html.

Naval Science & Technology: Enabling the Future Force

DTIC Science & Technology

2013-04-01

corn for disruptive technologies Laser Cooling Spintronics Bz 1st U.S. Intel satellite GRAB Semiconductors GaAs, GaN, SiC GPS...Payoff • Innovative and game-changing • Approved by Corporate Board • Delivers prototype Innovative Naval Prototypes (5-10 Year) Disruptive ... Technologies Free Electron Laser Integrated Topside EM Railgun Sea Base Enablers Tactical Satellite Large Displacement UUV AACUS Directed

The HyperV Full-Scale Contoured-Gap Coaxial Plasma Railgun

NASA Astrophysics Data System (ADS)

Brockington, Samuel; Case, Andrew; Messer, Sarah; Bomgardner, Richard; Elton, Raymond; Wu, Linchun; Witherspoon, F. Douglas

2009-11-01

HyperV has been developing pulsed plasma injected coaxial railguns with a contoured gap profile designed to mitigate the blowby instability. Previous work using half-scale guns has been successful in launching 150 μg plasmas at 90 km/s [1]. In order to meet the original goal of 200 μg at 200 km/s the full-scale coaxial plasma gun has been constructed, and initial testing is beginning. This new plasma gun consists of two machined aluminum electrodes and a UHMW polyethylene breech insulator. The gun is breech fed by 64 ablative polyethylene capillary discharge units identical to the half-scale gun units. Maximum accelerator energy storage has also been increased 50%. Refractory coatings may be necessary to allow full current (˜800 kA) operation. The outer electrode includes 24 small diagnostic ports for optical and magnetic probe access to the plasma inside the gun to allow direct measurement of the plasma armature dynamics. Initial test data from the full-scale coax gun will be presented along with plans for future testing. Work supported by the U.S. DOE Office of Fusion Energy Sciences.[4pt] [1] F. D. Witherspoon, A. Case, S. Messer, R. Bomgardner, M. Phillips, S. Brockington, R. Elton, ``Contoured Gap Coaxial Plasma Gun with Injected Plasma Armature'' Rev. Sci. Instr. submitted (2009)

STS-39 Discovery, Orbiter Vehicle (OV) 103, crew insignia

NASA Image and Video Library

1990-10-01

STS039-S-001 (October 1990) --- The arrowhead shape of the STS-39 crew patch represents a skyward aim to learn more about our planet's atmosphere and space environment in support of the Department of Defense. Our national symbol is represented by the star constellation Aguila (the eagle) as its brightest star, Altair, lifts a protective canopy above Earth. The space shuttle encircles the spectrum which represents x-ray, ultraviolet, visible and infrared electromagnetic radiation to be measured by a variety of scientific instruments. Experiments will be operated within the payload bay and aboard a free-flying satellite which will be deployed and retrieved during the mission. The patch was designed by the STS-39 crew. The NASA insignia design for space shuttle flights is reserved for use by the astronauts and for other official use as the NASA Administrator may authorize. Public availability has been approved only in the form of illustrations by the various news media. When and if there is any change in this policy, which we do not anticipate, it will be publicly announced. Photo credit: NASA

40 CFR Appendix A to Subpart Gg of... - Specialty Coating Definitions

Code of Federal Regulations, 2012 CFR

2012-07-01

... electromagnetic energy spectrum, such as the ultraviolet, visible, infrared, or microwave regions. Uses include, but are not limited to, lightning strike protection, electromagnetic pulse (EMP) protection, and radar.... Electrostatic discharge and electromagnetic interference (EMI) coating—A coating applied to space vehicles...

40 CFR Appendix A to Subpart Gg of... - Specialty Coating Definitions

Code of Federal Regulations, 2011 CFR

2011-07-01

... electromagnetic energy spectrum, such as the ultraviolet, visible, infrared, or microwave regions. Uses include, but are not limited to, lightning strike protection, electromagnetic pulse (EMP) protection, and radar.... Electrostatic discharge and electromagnetic interference (EMI) coating—A coating applied to space vehicles...

40 CFR Appendix A to Subpart Gg of... - Specialty Coating Definitions

Code of Federal Regulations, 2010 CFR

2010-07-01

... electromagnetic energy spectrum, such as the ultraviolet, visible, infrared, or microwave regions. Uses include, but are not limited to, lightning strike protection, electromagnetic pulse (EMP) protection, and radar.... Electrostatic discharge and electromagnetic interference (EMI) coating—A coating applied to space vehicles...

40 CFR Appendix A to Subpart Gg of... - Specialty Coating Definitions

Code of Federal Regulations, 2014 CFR

2014-07-01

... electromagnetic energy spectrum, such as the ultraviolet, visible, infrared, or microwave regions. Uses include, but are not limited to, lightning strike protection, electromagnetic pulse (EMP) protection, and radar.... Electrostatic discharge and electromagnetic interference (EMI) coating—A coating applied to space vehicles...

40 CFR Appendix A to Subpart Gg of... - Specialty Coating Definitions

Code of Federal Regulations, 2013 CFR

2013-07-01

... electromagnetic energy spectrum, such as the ultraviolet, visible, infrared, or microwave regions. Uses include, but are not limited to, lightning strike protection, electromagnetic pulse (EMP) protection, and radar.... Electrostatic discharge and electromagnetic interference (EMI) coating—A coating applied to space vehicles...

Analytical solution of electromagnetic radiation by a vertical electric dipole inside the earth and the effect of atmospheric electrical conductivity inhomogeneity

NASA Astrophysics Data System (ADS)

Mosayebidorcheh, Taha; Hosseinibalam, Fahimeh; Hassanzadeh, Smaeyl

2017-11-01

In this paper, the effect of atmospheric electrical conductivity on the electromagnetic waves radiated by a vertical electric dipole located in the earth, near the surface of the earth, is investigated. As far as electrical conductivity is concerned, the atmosphere is divided into three areas, in which the electrical conductivity changes with altitude. The Maxwell equations in these areas are investigated as well. Using the differential transform method, the differential equation is solved in a way that atmospheric electrical conductivity is variable. Solving the problem in these areas indicates that electrical conductivity in the middle and lower areas of atmosphere may be ignored. However, in the upper areas of atmosphere, the magnitude of the magnetic field in the ionosphere at a frequency of 10 kHz at night is five times smaller when electrical conductivity is considered compared to when it is neglected.

Electromagnetic Ion Cyclotron Waves Detected by Kaguya and Geotail in the Earth's Magnetotail

NASA Astrophysics Data System (ADS)

Nakagawa, Tomoko; Nishino, Masaki N.; Tsunakawa, Hideo; Takahashi, Futoshi; Shibuya, Hidetoshi; Shimizu, Hisayoshi; Matsushima, Masaki; Saito, Yoshifumi

2018-02-01

Narrowband electromagnetic ion cyclotron waves first discovered by the Apollo 15 and 16 Lunar Surface Magnetometers were surveyed in the magnetic field data obtained by the Kaguya satellite at an altitude of ˜100 km above the Moon in the tail lobe and plasma sheet boundary layer of the Earth's magnetosphere. The frequencies of the waves were typically 0.7 times the local proton cyclotron frequency, and 75% of the waves were left hand polarized with respect to the background magnetic field. They had a significant compressional component and comprised several discrete packets. They were detected on the dayside, nightside, and above the terminator of the Moon, irrespective of the lunar magnetic anomaly, or the magnetic connection to the lunar surface. The waves with the same characteristics were detected by Geotail in the absence of the Moon in the magnetotail. The most likely energy source of the electromagnetic ion cyclotron waves is the ring beam ions in the plasma sheet boundary layer.

The effects of radiation on angiogenesis.

PubMed

Grabham, Peter; Sharma, Preety

2013-10-26

The average human body contains tens of thousands of miles of vessels that permeate every tissue down to the microscopic level. This makes the human vasculature a prime target for an agent like radiation that originates from a source and passes through the body. Exposure to radiation released during nuclear accidents and explosions, or during cancer radiotherapy, is well known to cause vascular pathologies because of the ionizing effects of electromagnetic radiations (photons) such as gamma rays. There is however, another type of less well-known radiation - charged ion particles, and these atoms stripped of electrons, have different physical properties to the photons of electromagnetic radiation. They are either found in space or created on earth by particle collider facilities, and are of significant recent interest due to their enhanced effectiveness and increasing use in cancer radiotherapy, as well as a health risk to the growing number of people spending time in the space environment. Although there is to date, relatively few studies on the effects of charged particles on the vascular system, a very different picture of the biological effects of these particles compared to photons is beginning to emerge. These under researched biological effects of ion particles have a large impact on the health consequences of exposure. In this short review, we will discuss the effects of charged particles on an important biological process of the vascular system, angiogenesis, which creates and maintains the vasculature and is highly important in tumor vasculogenesis.

The effects of radiation on angiogenesis

PubMed Central

2013-01-01

The average human body contains tens of thousands of miles of vessels that permeate every tissue down to the microscopic level. This makes the human vasculature a prime target for an agent like radiation that originates from a source and passes through the body. Exposure to radiation released during nuclear accidents and explosions, or during cancer radiotherapy, is well known to cause vascular pathologies because of the ionizing effects of electromagnetic radiations (photons) such as gamma rays. There is however, another type of less well-known radiation – charged ion particles, and these atoms stripped of electrons, have different physical properties to the photons of electromagnetic radiation. They are either found in space or created on earth by particle collider facilities, and are of significant recent interest due to their enhanced effectiveness and increasing use in cancer radiotherapy, as well as a health risk to the growing number of people spending time in the space environment. Although there is to date, relatively few studies on the effects of charged particles on the vascular system, a very different picture of the biological effects of these particles compared to photons is beginning to emerge. These under researched biological effects of ion particles have a large impact on the health consequences of exposure. In this short review, we will discuss the effects of charged particles on an important biological process of the vascular system, angiogenesis, which creates and maintains the vasculature and is highly important in tumor vasculogenesis. PMID:24160185

Air-Cored Linear Induction Motor for Earth-to-Orbit Systems

NASA Technical Reports Server (NTRS)

Zabar, Zivan; Levi, Enrico; Birenbaum, Leo

1996-01-01

The need for lowering the cost of Earth-to-Orbit (ETO) launches has prompted consideration of electromagnetic launchers. A preliminary design based on the experience gained in an advanced type of coilgun and on innovative ideas shows that such a launcher is technically feasible with almost off-the-shelf components.

Using the in-line component for fixed-wing EM 1D inversion

NASA Astrophysics Data System (ADS)

Smiarowski, Adam

2015-09-01

Numerous authors have discussed the utility of multicomponent measurements. Generally speaking, for a vertical-oriented dipole source, the measured vertical component couples to horizontal planar bodies while the horizontal in-line component couples best to vertical planar targets. For layered-earth cases, helicopter EM systems have little or no in-line component response and as a result much of the in-line signal is due to receiver coil rotation and appears as noise. In contrast to this, the in-line component of a fixed-wing airborne electromagnetic (AEM) system with large transmitter-receiver offset can be substantial, exceeding the vertical component in conductive areas. This paper compares the in-line and vertical response of a fixed-wing airborne electromagnetic (AEM) system using a half-space model and calculates sensitivity functions. The a posteriori inversion model parameter uncertainty matrix is calculated for a bathymetry model (conductive layer over more resistive half-space) for two inversion cases; use of vertical component alone is compared to joint inversion of vertical and in-line components. The joint inversion is able to better resolve model parameters. An example is then provided using field data from a bathymetry survey to compare the joint inversion to vertical component only inversion. For each inversion set, the difference between the inverted water depth and ship-measured bathymetry is calculated. The result is in general agreement with that expected from the a posteriori inversion model parameter uncertainty calculation.

Geological and geophysical field investigations from a lunar base at Mare Smythii

NASA Technical Reports Server (NTRS)

Spudis, Paul D.; Hood, Lon L.

1992-01-01

Mare Smythii, located on the equator and east limb of the Moon, has a great variety of scientific and economic uses as the site for a permanent lunar base. Here a complex could be established that would combine the advantages of a nearside base (for ease of communications with Earth and normal operations) with those of a farside base (for shielding a radio astronomical observatory from the electromagnetic noise of Earth). The Mare Smythii region displays virtually the entire known range of geological processes and materials found on the Moon; from this site, a series of field traverses and investigations could be conducted that would provide data on and answers to fundamental questions in lunar geoscience. This endowment of geological materials also makes the Smythii region attractive for the mining of resources for use both on the Moon and in Earth-Moon space. We suggest that the main base complex be located at 0, 90 deg E, within the mare basalts of the Smythii basin; two additional outposts would be required, one at 0, 81 deg E to maintain constant communications with Earth, and and the other, at 0, 101 deg E on the lunar farside, to serve as a radio astronomical observatory. The bulk of lunar surface activities could be conducted by robotic teleoperations under the direct control of the human inhabitants of the base.

A note on the electromagnetic irradiation in a holed spatial region: A space-time approach

NASA Astrophysics Data System (ADS)

Botelho, Luiz C. L.

2017-02-01

We study the role of the homological topological property of a space-time with holes (a multiple connected manifold) on the formal solution of the electromagnetic irradiation problem taking place on these “holed” space-times. In this paper, in addition to the main focus of study, we present as well important studies on this irradiation problem on other mathematical frameworks.

Detection of Ionospheric Alfven Resonator Signatures Onboard C/NOFS: Implications for IRI Modeling

NASA Technical Reports Server (NTRS)

Simoes, F.; Klenzing, J.; Ivanov, S.; Pfaff, R.; Rowland, D.; Bilitza, D.

2011-01-01

The 2008-2009 long-lasting solar minimum activity has been the one of its kind since the dawn of space age, offering exceptional conditions for investigating space weather in the near-Earth environment. First ever detection of Ionospheric Alfven Resonator (IAR) signatures in orbit offers new means for investigating ionospheric electrodynamics, namely MHD (MagnetoHydroDynamics) wave propagation, aeronomy processes, ionospheric dynamics, and Sun-Earth connection mechanisms at a local scale. Local and global plasma density heterogeneities in the ionosphere and magnetosphere allow for formation of waveguides and resonators where magnetosonic and shear Alfven waves propagate. The ionospheric magnetosonic waveguide results from complete magnetosonic wave reflection about the ionospheric F-region peak, where the Alfven index of refraction presents a maximum. MHD waves can also be partially trapped in the vertical direction between the lower boundary of the ionosphere and the magnetosphere, a resonance mechanism known as IAR. In this work we present C/NOFS (Communications/Navigation Outage Forecasting System) Extremely Low Frequency (ELF) electric field measurements related to IAR signatures, discuss the resonance and wave propagation mechanisms in the ionosphere, and address the electromagnetic inverse problem from which electron/ion distributions can be derived. These peculiar IAR electric field measurements provide new, complementary methodologies for inferring ionospheric electron and ion density profiles, and also contribute for the investigation of ionosphere dynamics and space weather monitoring. Specifically, IAR spectral signatures measured by C/NOFS contribute for improving the International Reference Ionosphere (IRI) model, namely electron density and ion composition.

Design and Development of High Voltage Direct Current (DC) Sources for the Solar Array Module Plasma Interaction Experiment

NASA Technical Reports Server (NTRS)

Bibyk, Irene K.; Wald, Lawrence W.

1995-01-01

Two programmable, high voltage DC power supplies were developed as part of the flight electronics for the Solar Array Module Plasma Interaction Experiment (SAMPIE). SAMPIE's primary objectives were to study and characterize the high voltage arcing and parasitic current losses of various solar cells and metal samples within the space plasma of low earth orbit (LEO). High voltage arcing can cause large discontinuous changes in spacecraft potential which lead to damage of the power system materials and significant Electromagnetic Interference (EMI). Parasitic currents cause a change in floating potential which lead to reduced power efficiency. These primary SAMPIE objectives were accomplished by applying artificial biases across test samples over a voltage range from -600 VDC to +300 VDC. This paper chronicles the design, final development, and test of the two programmable high voltage sources for SAMPIE. The technical challenges to the design for these power supplies included vacuum, space plasma effects, thermal protection, Shuttle vibrations and accelerations.

Analysis of HEMCL Railgun Insulator Damage

DTIC Science & Technology

2006-06-01

pyrolytic epoxy degradation and glass fiber softening and liquification in the insulator, it is determined that rail-to-rail plasmas are present behind...produces epoxy decomposition products in the form of gases, oils , waxes and chars solid (heavily cross-linked residues) [4]. The nature of the... pyrolytic decomposition product (wax) of the epoxy as in the fired specimens. Figures 6 and 7 are typical examples of glass fiber softening and

Friction and Wear Sciences for a Highly Durable Railgun Weapon

DTIC Science & Technology

2007-10-01

FFT- Based Numerical Methods for Elasto-Plastic Contacts of Nominally Flat Surfaces,” to appear in Journal of Applied Mechanics. 20. Jin, X...is the fusion enthalpy per unit mass, C!"" ~ = and ! ~ is a dimensionless coefficient and 100 ~ !" . Listed in Table I are the material’s...searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments

LeadingEdge: Challenges and Solutions for the 21st Century, Electromagnetic Environmental Effects. Volume 7, Issue 1, 2009

DTIC Science & Technology

2009-01-01

Hazards of Electromagnet - ic Radiation to Ordnance ( HERO ). Below decks spaces, such as ammunition storage lockers and...Navy’s Hazards of Electromagnetic Radiation to Ordnance ( HERO ) program. Unlike other services deployed in our nation’s defense, our sailors liter...also provides infor- mation on other general HERO requirements. The Electromagnetic Radiation Hazards ( Hazards to Ordnance ) Datasheets2

Electromagnetic radiation from beam-plasma instabilities

NASA Technical Reports Server (NTRS)

Stenzel, R. L.; Whelan, D. A.

1982-01-01

The mechanism by which unstable electrostatic waves of an electron-beam plasma system are converted into observed electromagnetic waves is of great current interest in space plasma physics. Electromagnetic radiation arises from both natural beam-plasma systems, e.g., type III solar bursts and kilometric radiation, and from man-made electron beams injected from rockets and spacecraft. In the present investigation the diagnostic difficulties encountered in space plasmas are overcome by using a large laboratory plasma. A finite diameter (d approximately equal to 0.8 cm) electron beam is injected into a uniform quiescent magnetized afterglow plasma of dimensions large compared with electromagnetic wavelength. Electrostatic waves grow, saturate and decay within the uniform central region of the plasma volume so that linear mode conversion on density gradients can be excluded as a possible generation mechanism for electromagnetic waves.

Antenna design and implementation for the future space Ultra-Long wavelength radio telescope

NASA Astrophysics Data System (ADS)

Chen, Linjie; Aminaei, Amin; Gurvits, Leonid I.; Wolt, Marc Klein; Pourshaghaghi, Hamid Reza; Yan, Yihua; Falcke, Heino

2018-04-01

In radio astronomy, the Ultra-Long Wavelengths (ULW) regime of longer than 10 m (frequencies below 30 MHz), remains the last virtually unexplored window of the celestial electromagnetic spectrum. The strength of the science case for extending radio astronomy into the ULW window is growing. However, the opaqueness of the Earth's ionosphere makes ULW observations by ground-based facilities practically impossible. Furthermore, the ULW spectrum is full of anthropogenic radio frequency interference (RFI). The only radical solution for both problems is in placing an ULW astronomy facility in space. We present a concept of a key element of a space-borne ULW array facility, an antenna that addresses radio astronomical specifications. A tripole-type antenna and amplifier are analysed as a solution for ULW implementation. A receiver system with a low power dissipation is discussed as well. The active antenna is optimized to operate at the noise level defined by the celestial emission in the frequency band 1 - 30 MHz. Field experiments with a prototype tripole antenna enabled estimates of the system noise temperature. They indicated that the proposed concept meets the requirements of a space-borne ULW array facility.

Integrity of the DNA and Cellular Ultrastructure of Cryptoendolithic Fungi in Space or Mars Conditions: A 1.5-Year Study at the International Space Station.

PubMed

Onofri, Silvano; Selbmann, Laura; Pacelli, Claudia; de Vera, Jean Pierre; Horneck, Gerda; Hallsworth, John E; Zucconi, Laura

2018-06-19

The black fungi Cryomyces antarcticus and Cryomyces minteri are highly melanized and are resilient to cold, ultra-violet, ionizing radiation and other extreme conditions. These microorganisms were isolated from cryptoendolithic microbial communities in the McMurdo Dry Valleys (Antarctica) and studied in Low Earth Orbit (LEO), using the EXPOSE-E facility on the International Space Station (ISS). Previously, it was demonstrated that C. antarcticus and C. minteri survive the hostile conditions of space (vacuum, temperature fluctuations, and the full spectrum of extraterrestrial solar electromagnetic radiation), as well as Mars conditions that were simulated in space for a 1.5-year period. Here, we qualitatively and quantitatively characterize damage to DNA and cellular ultrastructure in desiccated cells of these two species, within the frame of the same experiment. The DNA and cells of C. antarcticus exhibited a higher resistance than those of C. minteri . This is presumably attributable to the thicker (melanized) cell wall of the former. Generally, DNA was readily detected (by PCR) regardless of exposure conditions or fungal species, but the C. minteri DNA had been more-extensively mutated. We discuss the implications for using DNA, when properly shielded, as a biosignature of recently extinct or extant life.

Illusion optics: Optically transforming the nature and the location of electromagnetic emissions

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

Yi, Jianjia; Tichit, Paul-Henri; Burokur, Shah Nawaz, E-mail: shah-nawaz.burokur@u-psud.fr

Complex electromagnetic structures can be designed by using the powerful concept of transformation electromagnetics. In this study, we define a spatial coordinate transformation that shows the possibility of designing a device capable of producing an illusion on an antenna radiation pattern. Indeed, by compressing the space containing a radiating element, we show that it is able to change the radiation pattern and to make the radiation location appear outside the latter space. Both continuous and discretized models with calculated electromagnetic parameter values are presented. A reduction of the electromagnetic material parameters is also proposed for a possible physical fabrication ofmore » the device with achievable values of permittivity and permeability that can be obtained from existing well-known metamaterials. Following that, the design of the proposed antenna using a layered metamaterial is presented. Full wave numerical simulations using Finite Element Method are performed to demonstrate the performances of such a device.« less

Analysis of electromagnetic interference from power system processing and transmission components for Space Station Freedom

NASA Technical Reports Server (NTRS)

Barber, Peter W.; Demerdash, Nabeel A. O.; Hurysz, B.; Luo, Z.; Denny, Hugh W.; Millard, David P.; Herkert, R.; Wang, R.

1992-01-01

The goal of this research project was to analyze the potential effects of electromagnetic interference (EMI) originating from power system processing and transmission components for Space Station Freedom. The approach consists of four steps: (1) developing analytical tools (models and computer programs); (2) conducting parameterization (what if?) studies; (3) predicting the global space station EMI environment; and (4) providing a basis for modification of EMI standards.

Space Experiments with Particle Accelerators (SEPAC)

NASA Technical Reports Server (NTRS)

Taylor, William W. L.

1994-01-01

The scientific emphasis of this contract has been on the physics of beam ionosphere interactions, in particular, what are the plasma wave levels stimulated by the Space Experiments with Particle Accelerators (SEPAC) electron beam as it is ejected from the Electron Beam Accelerator (EBA) and passes into and through the ionosphere. There were two different phenomena expected. The first was generation of plasma waves by the interaction of the DC component of the beam with the plasma of the ionosphere, by wave particle interactions. The second was the generation of waves at the pulsing frequency of the beam (AC component). This is referred to as using the beam as a virtual antenna, because the beam of electrons is a coherent electrical current confined to move along the earth's magnetic field. As in a physical antenna, a conductor at a radio or TV station, the beam virtual antenna radiates electromagnetic waves at the frequency of the current variations. These two phenomena were investigated during the period of this contract.

Relativistic runaway breakdown in low-frequency radio

NASA Astrophysics Data System (ADS)

Füllekrug, Martin; Roussel-Dupré, Robert; Symbalisty, Eugene M. D.; Chanrion, Olivier; Odzimek, Anna; van der Velde, Oscar; Neubert, Torsten

2010-01-01

The electromagnetic radiation emitted by an electron avalanche beam resulting from relativistic runaway breakdown within the Earth's atmosphere is investigated. It is found from theoretical modeling with a computer simulation that the electron beam emits electromagnetic radiation which is characterized by consecutive broadband pulses in the low-frequency radio range from ˜10 to 300 kHz at a distance of ˜800 km. Experimental evidence for the existence of consecutive broadband pulses is provided by low-frequency radio observations of sprite-producing lightning discharges at a distance of ˜550 km. The measured broadband pulses occur ˜4-9 ms after the sprite-producing lightning discharge, they exhibit electromagnetic radiation which mainly spans the frequency range from ˜50 to 350 kHz, and they exhibit complex waveforms without the typical ionospheric reflection of the first hop sky wave. Two consecutive pulses occur ˜4.5 ms and ˜3 ms after the causative lightning discharge and coincide with the sprite luminosity. It is concluded that relativistic runaway breakdown within the Earth's atmosphere can emit broadband electromagnetic pulses and possibly generates sprites. The source location of the broadband pulses can be determined with an interferometric network of wideband low-frequency radio receivers to lend further experimental support to the relativistic runaway breakdown theory.

Real-time holographic surveillance system

DOEpatents

Collins, H. Dale; McMakin, Douglas L.; Hall, Thomas E.; Gribble, R. Parks

1995-01-01

A holographic surveillance system including means for generating electromagnetic waves; means for transmitting the electromagnetic waves toward a target at a plurality of predetermined positions in space; means for receiving and converting electromagnetic waves reflected from the target to electrical signals at a plurality of predetermined positions in space; means for processing the electrical signals to obtain signals corresponding to a holographic reconstruction of the target; and means for displaying the processed information to determine nature of the target. The means for processing the electrical signals includes means for converting analog signals to digital signals followed by a computer means to apply a backward wave algorithm.

The comparison of SRs' variation affected by solar events observed in America and in China

NASA Astrophysics Data System (ADS)

Yu, H.; Williams, E.

2017-12-01

Schumann Resonances(SRs) are the electromagnetic resonance wave propagating in the earth-ionosphere cavity. Its characteristic of propagation are modified by the variation of ionosphere. So SRs can be the tools of monitoring the ionosphere which is often perturbed by solar events, x-ray emission and some other space-weather events (Roldugin et.al., 2004, De et al., 2010; Satori et.al., 2015). In present work, the amplitude and intrinsic frequencies of SRs observed at RID station in America and YSH station in China are compared. The variation of SRs during the solar flare on Feb. 15, 2011 are analyzed. Two-Dimensional Telegraph Equation(TDTE) method is used to simulate the perturbation of ionosphere by solar proton events. From the simulation and observation, the asymmetric construction of ionoshphere which is perturbed by the solar event will affect the amplitudes and frequencies of SRs. Due to the interfere influence of forward and backward propagation of electromagnetic field, the SR amplitude on different station will present different variation. The distance among the lightning source, observer and perturbed area will produce the different variation of amplitude and frequency for different station' SR.

Ted Madden's Network Methods: Applications to the Earth's Schumann Resonances

NASA Astrophysics Data System (ADS)

Williams, E. R.; Yu, H.

2014-12-01

Ted Madden made clever use of electrical circuit concepts throughout his long career in geophysical research: induced polarization, DC resistivity, magnetotellurics, Schumann resonances, the transport properties of rocks and even elasticity and the brittle failure of stressed rocks. The general methods on network analogies were presented in a terse monograph (Madden, 1972) which came to be called "The Grey Peril" by his students, named more for the challenge of deciphering the material as for the color of its cover. This talk will focus on Ted's first major use of the transmission line analogy in treating the Earth's Schumann resonances. This approach in Madden and Thompson (1965) provided a greatly simplified two-dimensional treatment of an electromagnetic problem with a notable three-dimensional structure. This skillful treatment that included the role of the Earth's magnetic field also led to predictions that the Schumann resonance energy would leak into space, predictions that have been verified nearly 50 years later in satellite observations. An extension of the network analogy by Nelson (1967) using Green's function methods provides a means to treat the inverse problem for the background Schumann resonances for the global lightning activity. The development of Madden's methods will be discussed along with concrete results based on them for the monitoring of global lightning.

Electromagnetic deep-probing (100-1000 kms) of the Earth's interior from artificial satellites: Constraints on the regional emplacement of crustal resources

NASA Technical Reports Server (NTRS)

Hermance, J. F. (Principal Investigator)

1981-01-01

A spherical harmonic analysis program is being tested which takes magnetic data in universal time from a set of arbitrarily space observatories and calculates a value for the instantaneous magnetic field at any point on the globe. The calculation is done as a least mean-squares value fit to a set of spherical harmonics up to any desired order. The program accepts as a set of input the orbit position of a satellite coordinates it with ground-based magnetic data for a given time. The output is a predicted time series for the magnetic field on the Earth's surface at the (r, theta) position directly under the hypothetically orbiting satellite for the duration of the time period of the input data set. By tracking the surface magnetic field beneath the satellite, narrow-band averages crosspowers between the spatially coordinated satellite and the ground-based data sets are computed. These crosspowers are used to calculate field transfer coefficients with minimum noise distortion. The application of this technique to calculating the vector response function W is discussed.

Real-time wideband cylindrical holographic surveillance system

DOEpatents

Sheen, David M.; McMakin, Douglas L.; Hall, Thomas E.; Severtsen, Ronald H.

1999-01-01

A wideband holographic cylindrical surveillance system including a transceiver for generating a plurality of electromagnetic waves; antenna for transmitting the electromagnetic waves toward a target at a plurality of predetermined positions in space; the transceiver also receiving and converting electromagnetic waves reflected from the target to electrical signals at a plurality of predetermined positions in space; a computer for processing the electrical signals to obtain signals corresponding to a holographic reconstruction of the target; and a display for displaying the processed information to determine nature of the target. The computer has instructions to apply Fast Fourier Transforms and obtain a three dimensional cylindrical image.

Real-time wideband holographic surveillance system

DOEpatents

Sheen, David M.; Collins, H. Dale; Hall, Thomas E.; McMakin, Douglas L.; Gribble, R. Parks; Severtsen, Ronald H.; Prince, James M.; Reid, Larry D.

1996-01-01

A wideband holographic surveillance system including a transceiver for generating a plurality of electromagnetic waves; antenna for transmitting the electromagnetic waves toward a target at a plurality of predetermined positions in space; the transceiver also receiving and converting electromagnetic waves reflected from the target to electrical signals at a plurality of predetermined positions in space; a computer for processing the electrical signals to obtain signals corresponding to a holographic reconstruction of the target; and a display for displaying the processed information to determine nature of the target. The computer has instructions to apply a three dimensional backward wave algorithm.

Real-time wideband holographic surveillance system

DOEpatents

Sheen, D.M.; Collins, H.D.; Hall, T.E.; McMakin, D.L.; Gribble, R.P.; Severtsen, R.H.; Prince, J.M.; Reid, L.D.

1996-09-17

A wideband holographic surveillance system including a transceiver for generating a plurality of electromagnetic waves; antenna for transmitting the electromagnetic waves toward a target at a plurality of predetermined positions in space; the transceiver also receiving and converting electromagnetic waves reflected from the target to electrical signals at a plurality of predetermined positions in space; a computer for processing the electrical signals to obtain signals corresponding to a holographic reconstruction of the target; and a display for displaying the processed information to determine nature of the target. The computer has instructions to apply a three dimensional backward wave algorithm. 28 figs.

Aspects of scintillation modelling in LEO-ground free-space optical communications

NASA Astrophysics Data System (ADS)

Moll, Florian

2017-10-01

Free-space optical communications can be used to transmit data from low Earth orbit satellites to ground with very high data rate. In the last section of the downlink, the electro-magnetic wave propagates through the turbulent atmosphere which is characterized by random index of refraction fluctuations. The propagating wave experiences phase distortions that lead to intensity scintillation in the aperture plane of the receiving telescope. For quantification, an appropriate scintillation model is needed. Approaches to analytically model the scintillation exist. Parameterization of the underlying turbulence profile (Cn2 profile) is however difficult. The Cn2 profiles are often site-specific and thus inappropriate or generic and thus too complex for a feasible deployment. An approach that directly models the scintillation effect based on measurements without claiming to be generic is therefore more feasible. Since measurements are sparse, a combination with existing theoretical framework is feasible to develop a new scintillation model that focuses on low earth orbit to ground free-space optical communications link design with direct detection. The paper addresses several questions one has to answer while analyzing the measurements data and selection of the theoretical models for the LEO downlink scenario. The first is the question of a suitable yet ease to use simple Cn2 profile. The HAP model is analyzed for its feasibility in this scenario since it includes a more realistic boundary layer profile decay than the HV model. It is found that the HAP model needs to be modified for a feasible deployment in the LEO downlink scenario for night time. The validity of the plane wave assumption in the downlink is discussed by model calculations of the scintillation index for a plane and Gaussian beam wave. Inaccuracies when using the plane earth model instead of the spherical earth model are investigated by analyzing the Rytov index. Impact of beam wander and non-ideal tracking are also discussed. Eventually, satellite measurements are discussed together with model calculations. It is found that the model calculation with the modified HAP turbulence profile fits the measurements. The plane wave assumption is valid for calculation of scintillation. The flat earth model is accurate enough to model scintillation over elevation when using the extended Rytov theory. The effect of beam wander is negligible. Further work needs to be carried out to elaborate a new scintillation model from the measurements and theory.

Electromagnetic wave absorbing properties of amorphous carbon nanotubes.

PubMed

Zhao, Tingkai; Hou, Cuilin; Zhang, Hongyan; Zhu, Ruoxing; She, Shengfei; Wang, Jungao; Li, Tiehu; Liu, Zhifu; Wei, Bingqing

2014-07-10

Amorphous carbon nanotubes (ACNTs) with diameters in the range of 7-50 nm were used as absorber materials for electromagnetic waves. The electromagnetic wave absorbing composite films were prepared by a dip-coating method using a uniform mixture of rare earth lanthanum nitrate doped ACNTs and polyvinyl chloride (PVC). The microstructures of ACNTs and ACNT/PVC composites were characterized using transmission electron microscope and X-ray diffraction, and their electromagnetic wave absorbing properties were measured using a vector-network analyzer. The experimental results indicated that the electromagnetic wave absorbing properties of ACNTs are superior to multi-walled CNTs, and greatly improved by doping 6 wt% lanthanum nitrate. The reflection loss (R) value of a lanthanum nitrate doped ACNT/PVC composite was -25.02 dB at 14.44 GHz, and the frequency bandwidth corresponding to the reflector loss at -10 dB was up to 5.8 GHz within the frequency range of 2-18 GHz.

Strong permanent magnet-assisted electromagnetic undulator

DOEpatents

Halbach, Klaus

1988-01-01

This invention discloses an improved undulator comprising a plurality of electromagnet poles located along opposite sides of a particle beam axis with alternate north and south poles on each side of the beam to cause the beam to wiggle or undulate as it travels generally along the beam axis and permanent magnets spaced adjacent the electromagnetic poles on each side of the axis of said particle beam in an orientation sufficient to reduce the saturation of the electromagnet poles whereby the field strength of the electromagnet poles can be increased beyond the normal saturation levels of the electromagnetic poles.

A strong permanent magnet-assisted electromagnetic undulator

DOEpatents

Halbach, K.

1987-01-30

This invention discloses an improved undulator comprising a plurality of electromagnet poles located along opposite sides of a particle beam axis with alternate north and south poles on each side of the beam to cause the beam to wiggle or undulate as it travels generally along the beam axis and permanent magnets spaced adjacent the electromagnetic poles on each side of the axis of said particle beam in an orientation sufficient to reduce the saturation of the electromagnet poles whereby the field strength of the electromagnet poles can be increased beyond the normal saturation levels of the electromagnetic poles. 4 figs.

A high-performance electric field detector for space missions

NASA Astrophysics Data System (ADS)

Badoni, D.; Ammendola, R.; Bertello, I.; Cipollone, P.; Conti, L.; De Santis, C.; Diego, P.; Masciantonio, G.; Picozza, P.; Sparvoli, R.; Ubertini, P.; Vannaroni, G.

2018-04-01

We present the prototype of an Electric Field Detector (EFD) for space applications, that has been developed in the framework of the Chinese-Italian collaboration on the CSES (China Seismo-Electromagnetic Satellite) forthcoming missions. In particular CSES-1 will be placed in orbit in the early 2018. The detector consists of spherical probes designed to be installed at the tips of four booms deployed from a 3-axes stabilized satellite. The instrument has been conceived for space-borne measurements of electromagnetic phenomena such as ionospheric waves, lithosphere-atmosphere-ionosphere-magnetosphere coupling and anthropogenic electromagnetic emissions. The detector allows to measure electric fields in a wide band of frequencies extending from quasi-DC up to about 4 MHz , with a sensitivity of the order of 1 μV / m in the ULF band. With these bandwidth and sensitivity, the described electric field detector represents a very performing and updated device for electric field measurements in space.

Electromagnetically Operated Counter

DOEpatents

Goldberg, H D; Goldberg, M I

1951-12-18

An electromagnetically operated counter wherein signals to be counted are applied to cause stepwise rotation of a rotatable element which is connected to a suitable register. The mechanism involved consists of a rotatable armature having three spaced cores of magnetic material and a pair of diametrically opposed electromagnets with a suitable pulsing circuit to actuate the magnets.

A new Predictive Model for Relativistic Electrons in Outer Radiation Belt

NASA Astrophysics Data System (ADS)

Chen, Y.

2017-12-01

Relativistic electrons trapped in the Earth's outer radiation belt present a highly hazardous radiation environment for spaceborne electronics. These energetic electrons, with kinetic energies up to several megaelectron-volt (MeV), manifest a highly dynamic and event-specific nature due to the delicate interplay of competing transport, acceleration and loss processes. Therefore, developing a forecasting capability for outer belt MeV electrons has long been a critical and challenging task for the space weather community. Recently, the vital roles of electron resonance with waves (including such as chorus and electromagnetic ion cyclotron) have been widely recognized; however, it is still difficult for current diffusion radiation belt models to reproduce the behavior of MeV electrons during individual geomagnetic storms, mainly because of the large uncertainties existing in input parameters. In this work, we expanded our previous cross-energy cross-pitch-angle coherence study and developed a new predictive model for MeV electrons over a wide range of L-shells inside the outer radiation belt. This new model uses NOAA POES observations from low-Earth-orbits (LEOs) as inputs to provide high-fidelity nowcast (multiple hour prediction) and forecast (> 1 day prediction) of the energization of MeV electrons as well as the evolving MeV electron distributions afterwards during storms. Performance of the predictive model is quantified by long-term in situ data from Van Allen Probes and LANL GEO satellites. This study adds new science significance to an existing LEO space infrastructure, and provides reliable and powerful tools to the whole space community.

Can Sunlight Shift the Earth onto a Different Orbit?

ERIC Educational Resources Information Center

Esposito, S.

2011-01-01

This article comes from a question asked by a student of mine: if the Sun radiates energy in the form of electromagnetic waves, could they shift the Earth from its current orbit on a suitable timescale? The answer to such a question is apparently obvious and trivial. Nevertheless, it requires an instructive reasoning and interesting estimates of…

Swarm: ESA's Magnetic Field Mission

NASA Astrophysics Data System (ADS)

Plank, G.; Floberghagen, R.; Menard, Y.; Haagmans, R.

2012-12-01

Swarm is the fifth Earth Explorer mission in ESA's Living Planet Programme, and is scheduled for launch in fall 2012. The objective of the Swarm mission is to provide the best-ever survey of the geomagnetic field and its temporal evolution using a constellation of three identical satellites. The mission shall deliver data that allow access to new insights into the Earth system by improved scientific understanding of the Earth's interior and near-Earth electromagnetic environment. After launch and triple satellite release at an initial altitude of about 490 km, a pair of the satellites will fly side-by-side with slowly decaying altitude, while the third satellite will be lifted to 530 km to complete the Swarm constellation. High-precision and high-resolution measurements of the strength, direction and variation of the magnetic field, complemented by precise navigation, accelerometer and electric field measurements, will provide the observations required to separate and model various sources of the geomagnetic field and near-Earth current systems. The mission science goals are to provide a unique view into Earth's core dynamics, mantle conductivity, crustal magnetisation, ionospheric and magnetospheric current systems and upper atmosphere dynamics - ranging from understanding the geodynamo to contributing to space weather. The scientific objectives and results from recent scientific studies will be presented. In addition the current status of the project, which is presently in the final stage of the development phase, will be addressed. A consortium of European scientific institutes is developing a distributed processing system to produce geophysical (Level 2) data products for the Swarm user community. The setup of the Swarm ground segment and the contents of the data products will be addressed. In case the Swarm satellites are already in orbit, a summary of the on-going mission operations activities will be given.

Electronic Combat in Space: Examining the Legality of Fielding a Space-Based Disruptive Electromagnetic Jamming System

DTIC Science & Technology

2007-06-15

particles ( asteroids and meteoroids), energetic charged particles (ions, protons, electrons, etc.), and electromagnetic and ionizing radiation (x-rays...These protocols include a ban on Non-Detectable Fragments; restrictions on the use of Mines , Booby Traps, and Other Devices; prohibitions on certain...

Map of low-frequency electromagnetic noise in the sky

NASA Astrophysics Data System (ADS)

Füllekrug, Martin; Mezentsev, Andrew; Watson, Robert; Gaffet, Stéphane; Astin, Ivan; Smith, Nathan; Evans, Adrian

2015-06-01

The Earth's natural electromagnetic environment is disturbed by anthropogenic electromagnetic noise. Here we report the first results from an electromagnetic noise survey of the sky. The locations of electromagnetic noise sources are mapped on the hemisphere above a distributed array of wideband receivers that operate in a small aperture configuration. It is found that the noise sources can be localized at elevation angles up to ˜60° in the sky, well above the horizon. The sky also exhibits zones with little or no noise that are found toward the local zenith and the southwest of the array. These results are obtained by a rigorous analysis of the residuals from the classic dispersion relation for electromagnetic waves using an array analysis of electric field measurements in the frequency range from ˜20 to 250 kHz. The observed locations of the noise sources enable detailed observations of ionospheric modification, for example, caused by particle precipitation and lightning discharges, while the observed exclusion zones enable the detection of weak natural electromagnetic emissions, for example, from streamers in transient luminous events above thunderclouds.

[Inefficiency of electrosmog-shielding mats. Part 2: radio frequency range].

PubMed

Leitgeb, N; Cech, R

2005-09-01

It could already be shown that electromagnetic shielding mats do not reduce but even enhance electric field exposure in daily life situations. By measurements and numerical simulations the claims of manufacturers were checked who pretend that radio frequency electromagnetic fields can be shielded to 99% and more, and transferred to earth by earth cables (if attached). It could be shown that in the radio frequency range such products do not fulfil the justified expectations of customers, but in most cases even cause the opposite. The results depend on the electric properties of the material. Good electric conductivity of shielding mats even considerably increases electromagnetic field exposure. To connect the mats with earth potential by an attached cable might increase the beliefs on a protective effect, however, this is not capable to enhance the shielding effect. The investigation demonstrates that in spite of references made to experts opinions manufacturers claims about the shielding efficiency of radio frequency fields are misleading and fool clients about the real situation. Overall, acquisition and use of electrosmog shielding mats must be discouraged. If at all, shielding can be reached by placing a shielding cover between the source and the person. However, even in this case, efficiency is much lower than promised by manufacturers and decreases even more if it is taken into account that the head naturally remains uncovered and hence unshielded.

Characterization of Metallic Coatings and Thin Films Produced by Railgun Deposition

DTIC Science & Technology

1988-01-01

homopolar generators (10), and compensating alternators (11) are capable of delivering mnegajoules of energy in less than a second. This advancement...a DC motor which consists of two rigid parallel conducting electrodes (rails) and a combined movable armature placed between them (7), Figure 2. The...discharge bank or homopolar generater, and the plasma device to another. The second study then ended with a group of experiments using an exploding wire

Laboratory for Extraterrestrial Physics

NASA Technical Reports Server (NTRS)

Vondrak, Richard R. (Technical Monitor)

2001-01-01

The NASA Goddard Space Flight Center (GSFC) Laboratory for Extraterrestrial Physics (LEP) performs experimental and theoretical research on the heliosphere, the interstellar medium, and the magnetospheres and upper atmospheres of the planets, including Earth. LEP space scientists investigate the structure and dynamics of the magnetospheres of the planets including Earth. Their research programs encompass the magnetic fields intrinsic to many planetary bodies as well as their charged-particle environments and plasma-wave emissions. The LEP also conducts research into the nature of planetary ionospheres and their coupling to both the upper atmospheres and their magnetospheres. Finally, the LEP carries out a broad-based research program in heliospheric physics covering the origins of the solar wind, its propagation outward through the solar system all the way to its termination where it encounters the local interstellar medium. Special emphasis is placed on the study of solar coronal mass ejections (CME's), shock waves, and the structure and properties of the fast and slow solar wind. LEP planetary scientists study the chemistry and physics of planetary stratospheres and tropospheres and of solar system bodies including meteorites, asteroids, comets, and planets. The LEP conducts a focused program in astronomy, particularly in the infrared and in short as well as very long radio wavelengths. We also perform an extensive program of laboratory research, including spectroscopy and physical chemistry related to astronomical objects. The Laboratory proposes, develops, fabricates, and integrates experiments on Earth-orbiting, planetary, and heliospheric spacecraft to measure the characteristics of planetary atmospheres and magnetic fields, and electromagnetic fields and plasmas in space. We design and develop spectrometric instrumentation for continuum and spectral line observations in the x-ray, gamma-ray, infrared, and radio regimes; these are flown on spacecraft to study the interplanetary medium, asteroids, comets, and planets. Suborbital sounding rockets and groundbased observing platforms form an integral part of these research activities. This report covers the period from approximately October 1999 through September 2000.

Dynamics of plankton populations in upwelling areas. [by remote sensors

NASA Technical Reports Server (NTRS)

Szekielda, K.

1974-01-01

Recent investigations of the upwelling area along the NW Coast of Africa which include studies with satellites are discussed. The detection of patchiness in temperature and plankton distribution in the upwelling area is of special interest because they can be investigated from space synoptically with repeated coverage. The recent satellite missions provide recordings in the infrared region of the electromagnetic spectrum (EMR) as well as in the visible part. The information from those two parts of the EMR is useful for establishing the sea surface temperature and plankton distribution in upwelling areas. The temperature distribution as observed with infrared sensors and the patchiness in plankton patterns are discussed as observed with the most recent satellites, namely the Earth Resources Technology Satellite (ERTS) and NOAA-2.

Kinetic theory of twisted waves: Application to space plasmas having superthermal population of species

NASA Astrophysics Data System (ADS)

Arshad, Kashif; Poedts, Stefaan; Lazar, Marian

2017-04-01

Nowadays electromagnetic (EM) fields have various applications in fundamental research, communication, and home appliances. Even though, there are still some subtle features of electromagnetic field known to us a century ago, yet to be utilized. It is because of the technical complexities to sense three dimensional electromagnetic field. An important characteristic of electromagnetic field is its orbital angular momentum (OAM). The angular momentum consists of two distinct parts; intrinsic part associated with the wave polarization or spin, and the extrinsic part associated with the orbital angular momentum (OAM). The orbital angular momentum (OAM) is inherited by helically phased light or helical (twisted) electric field. The investigations of Allen on lasers carrying orbital angular momentum (OAM), has initiated a new scientific and technological advancement in various growing fields, such as microscopy and imaging, atomic and nano-particle manipulation, ultra-fast optical communications, quantum computing, ionospheric radar facility to observe 3D plasma dynamics in ionosphere, photonic crystal fibre, OAM entanglement of two photons, twisted gravitational waves, ultra-intense twisted laser pulses and astrophysics. Recently, the plasma modes are also investigated with orbital angular momentum. The production of electron vortex beams and its applications are indicated by Verbeeck et al. The magnetic tornadoes (rotating magnetic field structures) exhibit three types of morphology i.e., spiral, ring and split. Leyser pumped helical radio beam carrying OAM into the Ionospheric plasma under High Frequency Active Auroral Research Program (HAARP) and characteristic ring shaped morphology is obtained by the optical emission spectrum of pumped plasma turbulence. The scattering phenomenon like (stimulated Raman and Brillouin backscattering) is observed to be responsible for the interaction between electrostatic and electromagnetic waves through orbital angular momentum. The ring shape morphology of a beam with orbital angular momentum (OAM) is ideal for the observation of solar corona around the sun where the intensity of the beam is minimum at the center, in solar experiments, and Earth's ionosphere. The twisted plasma modes carrying OAM are mostly studied either by the fluid theory or Maxwellian distributed Kinetic Theory. But most of the space plasmas and some laboratory plasmas have non-thermal distributions due to super-thermal population of the plasma particles. Therefore the Kinetic Theory of twisted plasma modes carrying OAM are recently studied using non-thermal (kappa) distribution of the super-thermal particles in the presence of the helical electric field and significant change in the damping rates are observed by tuning appropriate parameters.

An Overview of the Design and Development of the Geostationary Operational Environmental Satellite R-Series (GOES-R) Space Segment

NASA Technical Reports Server (NTRS)

Sullivan, Pamela C.; Krimchansky, Alexander; Walsh, Timothy J.

2017-01-01

The first of the National Oceanic and Atmospheric Administration (NOAA) Geostationary Operational Environmental Satellite R-series (GOES-R) satellites was launched in November 2016. GOES-R has been developed by NOAA in partnership with the National Aeronautics and Space Administration (NASA). The satellite represents a quantum leap in the state of the art for geostationary weather satellites by providing data from a suite of six new instruments. All instruments were developed expressly for this mission, and include two Earth-observing instruments (the Advanced Baseline Imager (ABI) and Geostationary Lightning Mapper (GLM)), two solar-viewing instruments (Solar Ultraviolet Imager (SUVI) and Extreme ultraviolet and X-ray Irradiance Sensors (EXIS)) and two in situ instruments (Space Environment In-Situ Suite (SEISS) and a magnetometer pair). In addition to hosting the instruments, GOES-R also accommodates several communication packages designed to collect and relay data for weather forecasting and emergency management. Accommodating the six instruments and four communication payloads imposed challenging and competing constraints on the satellite, including requirements for extremely stable earth and solar pointing, high-speed and nearly error-free instrument data transmission, and a very quiet electromagnetic background. To meet mission needs, GOES-R employed several technological innovations, including low-thrust rocket engines that allow instrument observations to continue during maneuvers, and the first civilian use of Global Positioning System-based orbit determination in geostationary orbit. This paper will provide a brief overview of the GOES-R satellite and its instruments as well as the developmental challenges involved in accommodating the instruments and communications payloads.

An Overview of the Design and Development of the GOES R-Series Space Segment

NASA Technical Reports Server (NTRS)

Sullivan, Pam; Krimchansky, Alexander; Walsh, Timothy

2017-01-01

The first of the National Oceanic and Atmospheric Administration (NOAA) Geostationary Operational Environmental Satellite R-series (GOES-R) satellites was launched in November 2016. GOES-R has been developed by NOAA in partnership with the National Aeronautics and Space Administration (NASA). The satellite represents a quantum leap in the state of the art for geostationary weather satellites by providing data from a suite of six new instruments. All instruments were developed expressly for this mission, and include two Earth-observing instruments (the Advanced Baseline Imager (ABI) and Geostationary Lightning Mapper (GLM)), two solar-viewing instruments (Solar Ultraviolet Imager (SUVI) and Extreme ultraviolet and X-ray Irradiance Sensors (EXIS)) and two in situ instruments (Space Environment In-Situ Suite (SEISS) and a magnetometer pair). In addition to hosting the instruments, GOES-R also accommodates several communication packages designed to collect and relay data for weather forecasting and emergency management. Accommodating the six instruments and four communication payloads imposed challenging and competing constraints on the satellite, including requirements for extremely stable earth and solar pointing, high-speed and nearly error-free instrument data transmission, and a very quiet electromagnetic background. To meet mission needs, GOES-R employed several technological innovations, including low-thrust rocket engines that allow instrument observations to continue during maneuvers, and the first civilian use of Global Positioning System-based orbit determination in geostationary orbit. This paper will provide a brief overview of the GOES-R satellite and its instruments as well as the developmental challenges involved in accommodating the instruments and communications payloads.

NASA's BARREL Mission in Sweden

NASA Image and Video Library

2017-12-08

The faint green glow of aurora can be seen above the clouds at Esrange Space Center in this photo from Aug. 23, 2016. Auroras are created by energetic electrons, which rain down from Earth’s magnetic bubble and interact with particles in the upper atmosphere to create glowing lights that stretch across the sky. The BARREL team is at Esrange Space Center near Kiruna, Sweden, launching a series of six scientific payloads on miniature scientific balloons. The NASA-funded BARREL – which stands for Balloon Array for Radiation-belt Relativistic Electron Losses – primarily measures X-rays in Earth’s atmosphere near the North and South Poles. These X-rays are produced by electrons raining down into the atmosphere from two giant swaths of radiation that surround Earth, called the Van Allen belts. Learning about the radiation near Earth helps us to better protect our satellites. Several of the BARREL balloons also carry instruments built by undergraduate students to measure the total electron content of Earth’s ionosphere, as well as the low-frequency electromagnetic waves that help to scatter electrons into Earth’s atmosphere. Though about 90 feet in diameter, the BARREL balloons are much smaller than standard football stadium-sized scientific balloons. This is the fourth campaign for the BARREL mission. BARREL is led by Dartmouth College in Hanover, New Hampshire. The undergraduate student instrument team is led by the University of Houston and funded by the Undergraduate Student Instrument Project out of NASA’s Wallops Flight Facility. For more information on NASA’s scientific balloon program, visit: www.nasa.gov/scientificballoons. Credit: NASA/University of Houston/Michael Greer NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Magnetohydrodynamic Convection in the Outer Core and its Geodynamic Consequences

NASA Technical Reports Server (NTRS)

Kuang, Weijia; Chao, Benjamin F.; Fang, Ming

2004-01-01

The Earth's fluid outer core is in vigorous convection through much of the Earth's history. In addition to generating and maintaining Earth s time-varying magnetic field (geodynamo), the core convection also generates mass redistribution in the core and a dynamical pressure field on the core-mantle boundary (CMB). All these shall result in various core-mantle interactions, and contribute to surface geodynamic observables. For example, electromagnetic core-mantle coupling arises from finite electrically conducting lower mantle; gravitational interaction occurs between the cores and the heterogeneous mantle; mechanical coupling may also occur when the CMB topography is aspherical. Besides changing the mantle rotation via the coupling torques, the mass-redistribution in the core shall produce a spatial-temporal gravity anomaly. Numerical modeling of the core dynamical processes contributes in several geophysical disciplines. It helps explain the physical causes of surface geodynamic observables via space geodetic techniques and other means, e.g. Earth's rotation variation on decadal time scales, and secular time-variable gravity. Conversely, identification of the sources of the observables can provide additional insights on the dynamics of the fluid core, leading to better constraints on the physics in the numerical modeling. In the past few years, our core dynamics modeling efforts, with respect to our MoSST model, have made significant progress in understanding individual geophysical consequences. However, integrated studies are desirable, not only because of more mature numerical core dynamics models, but also because of inter-correlation among the geophysical phenomena, e.g. mass redistribution in the outer core produces not only time-variable gravity, but also gravitational core-mantle coupling and thus the Earth's rotation variation. They are expected to further facilitate multidisciplinary studies of core dynamics and interactions of the core with other components of the Earth.

Formation of Imploding Plasma Liners for HEDP and MIF Application

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

Witherspoon, F. Douglas; Case, Andrew; Brockington, Samuel

Plasma jets with high density and velocity have a number of important applications in fusion energy and elsewhere, including plasma refueling, disruption mitigation in tokamaks, magnetized target fusion, injection of momentum into centrifugally confined mirrors, plasma thrusters, and high energy density plasmas (HEDP). In Magneto-Inertial Fusion (MIF), for example, an imploding material liner is used to compress a magnetized plasma to fusion conditions and to confine the resulting burning plasma inertially to obtain the necessary energy gain. The imploding shell may be solid, liquid, gaseous, or a combination of these states. The presence of the magnetic field in the targetmore » plasma suppresses thermal transport to the plasma shell, thus lowering the imploding power needed to compress the target to fusion conditions. This allows the required imploding momentum flux to be generated electromagnetically using off-the-shelf pulsed power technology. Practical schemes for standoff delivery of the imploding momentum flux are required and are open topics for research. One approach for accomplishing this, called plasma jet driven magneto-inertial fusion (PJMIF), uses a spherical array of pulsed plasma guns to create a spherically imploding shell of very high velocity, high momentum flux plasma. This approach requires development of plasma jet accelerators capable of achieving velocities of 50-200 km/s with very precise timing and density profiles, and with high total mass and density. Low-Z plasma jets would require the higher velocities, whereas very dense high-Z plasma shells could achieve the goal at velocities of only 50-100 km/s. In this report, we describe our work to develop the pulsed plasma gun technology needed for an experimental scientific exploration of the PJMIF concept, and also for the other applications mentioned earlier. The initial goal of a few hundred of hydrogen at 200 km/s was eventually replaced with accelerating 8000 μg of argon or xenon to 50 km/s for the Plasma Liner Experiment (PLX) at Los Alamos National Laboratory (LANL). Initial work used existing computational and analytical tools to develop and refine a specific plasma gun concept having a novel tapered coaxial electromagnetic accelerator contour with an array of symmetric ablative plasma injectors. The profile is designed to suppress the main barrier to success in coaxial guns, namely the blow-by instability in which the arc slips past and outruns the bulk of the plasma mass. Efforts to begin developing a set of annular non-ablative plasma injectors for the coaxial gun, in order to accelerate pure gases, resulted in development of linear parallel-plate MiniRailguns that turned out to work well as plasma guns in their own right and we subsequently chose them for an initial plasma liner experiment on the PLX facility at LANL. This choice was mainly driven by cost and schedule for that particular experiment, while longer term goals still projected use of coaxial guns for reactor-relevant applications for reasons of better symmetry, lower impurities, more compact plasma jet formation, and higher gun efficiency. Our efforts have focused mainly on 1) developing various plasma injection systems for both coax and linear railguns and ensuring they work reliably with the accelerator section, 2) developing a suite of plasma and gun diagnostics, 3) performing computational modeling to design and refine the plasma guns, 4) establishing a research facility dedicated to plasma gun development, and finally, 5) developing plasma guns and associated pulse power systems capable of achieving these goals and installing and testing the first two gun sets on the PLX facility at LANL. During the second funding cycle for this program, HyperV joined in a collaborative effort with LANL, the University of Alabama at Huntsville, and the University of New Mexico to perform a plasma liner experiment (PLX) to investigate the physics and technology of forming spherically imploding plasma liners. HyperV’s tasks focused on developing the plasma guns and associated pulse power systems required for the 30 gun experiment at LANL. Unfortunately, funding for the entire PLX collaborative project was terminated after only two years of the four year project due to program funding realignments which necessitated recompeting the project in midstream. Despite the loss of funding, HyperV installed two Mark1 guns and pulsed power systems on PLX, and jet characterization and merging experiments were subsequently successfully performed at LANL by the PLX Team. In parallel with those PLX experiments, HyperV continued its efforts to develop a plasma gun capable of meeting the PLX goal of 8 mg of argon at 50 km/s. HyperV was ultimately successful in this effort, demonstrating 10.8 mg at 52.8 km/s and 7.5 mg at 62.4 km/s with the Mark2 MiniRailgun.« less

47 CFR 25.138 - Blanket Licensing provisions of GSO FSS Earth Stations in the 18.3-18.8 GHz (space-to-Earth), 19...

Code of Federal Regulations, 2012 CFR

2012-10-01

... 47 Telecommunication 2 2012-10-01 2012-10-01 false Blanket Licensing provisions of GSO FSS Earth Stations in the 18.3-18.8 GHz (space-to-Earth), 19.7-20.2 GHz (space-to-Earth), 28.35-28.6 GHz (Earth-to-space), and 29.25-30.0 GHz (Earth-to-space) bands. 25.138 Section 25.138 Telecommunication FEDERAL...

47 CFR 25.138 - Blanket Licensing provisions of GSO FSS Earth Stations in the 18.3-18.8 GHz (space-to-Earth), 19...

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 2 2011-10-01 2011-10-01 false Blanket Licensing provisions of GSO FSS Earth Stations in the 18.3-18.8 GHz (space-to-Earth), 19.7-20.2 GHz (space-to-Earth), 28.35-28.6 GHz (Earth-to-space), and 29.25-30.0 GHz (Earth-to-space) bands. 25.138 Section 25.138 Telecommunication FEDERAL...

47 CFR 25.138 - Blanket Licensing provisions of GSO FSS Earth Stations in the 18.3-18.8 GHz (space-to-Earth), 19...

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Blanket Licensing provisions of GSO FSS Earth Stations in the 18.3-18.8 GHz (space-to-Earth), 19.7-20.2 GHz (space-to-Earth), 28.35-28.6 GHz (Earth-to-space), and 29.25-30.0 GHz (Earth-to-space) bands. 25.138 Section 25.138 Telecommunication FEDERAL...

47 CFR 25.138 - Blanket Licensing provisions of GSO FSS Earth Stations in the 18.3-18.8 GHz (space-to-Earth), 19...

Code of Federal Regulations, 2013 CFR

2013-10-01

... 47 Telecommunication 2 2013-10-01 2013-10-01 false Blanket Licensing provisions of GSO FSS Earth Stations in the 18.3-18.8 GHz (space-to-Earth), 19.7-20.2 GHz (space-to-Earth), 28.35-28.6 GHz (Earth-to-space), and 29.25-30.0 GHz (Earth-to-space) bands. 25.138 Section 25.138 Telecommunication FEDERAL...

47 CFR 25.138 - Licensing requirements for GSO FSS Earth Stations in the 18.3-18.8 GHz (space-to-Earth), 19.7-20...

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 2 2014-10-01 2014-10-01 false Licensing requirements for GSO FSS Earth Stations in the 18.3-18.8 GHz (space-to-Earth), 19.7-20.2 GHz (space-to-Earth), 28.35-28.6 GHz (Earth-to-space), and 29.25-30.0 GHz (Earth-to-space) bands. 25.138 Section 25.138 Telecommunication FEDERAL...

Research on radiation characteristic of plasma antenna through FDTD method.

PubMed

Zhou, Jianming; Fang, Jingjing; Lu, Qiuyuan; Liu, Fan

2014-01-01

The radiation characteristic of plasma antenna is investigated by using the finite-difference time-domain (FDTD) approach in this paper. Through using FDTD method, we study the propagation of electromagnetic wave in free space in stretched coordinate. And the iterative equations of Maxwell equation are derived. In order to validate the correctness of this method, we simulate the process of electromagnetic wave propagating in free space. Results show that electromagnetic wave spreads out around the signal source and can be absorbed by the perfectly matched layer (PML). Otherwise, we study the propagation of electromagnetic wave in plasma by using the Boltzmann-Maxwell theory. In order to verify this theory, the whole process of electromagnetic wave propagating in plasma under one-dimension case is simulated. Results show that Boltzmann-Maxwell theory can be used to explain the phenomenon of electromagnetic wave propagating in plasma. Finally, the two-dimensional simulation model of plasma antenna is established under the cylindrical coordinate. And the near-field and far-field radiation pattern of plasma antenna are obtained. The experiments show that the variation of electron density can introduce the change of radiation characteristic.

Nonlinear analysis of generalized cross-field current instability

NASA Technical Reports Server (NTRS)

Yoon, Peter H.; Lui, Anthony T. Y.

1993-01-01

Analysis of the generalized cross-field current instability is carried out in which cross-field drift of both the ions and electrons and their temperatures are permitted to vary in time. The unstable mode under consideration is the electromagnetic generalization of the classical modified-two-stream instability. The generalized instability is made of the modified-two-stream and ion-Weibel modes. The relative importance of the features associated with the ion-Weibel mode and those of the modified-two-stream mode is assessed. Specific applications are made to the Earth's neutral sheet prior to substorm onset and to the Earth's bow shock. The numerical solution indicates that the ion-Weibel mode dominates in the Earth's neutral sheet environment. In contrast, the situation for the bow shock is dominated by the modified-two-stream mode. Notable differences are found between the present calculation and previous results on ion-Weibel mode which restrict the analysis to only parallel propagating waves. However, in the case of Earth's bow shock for which the ion-Weibel mode plays no important role, the inclusion of the electromagnetic ion response is found to differ little from the previous results which treats ions responding only to the electrostatic component of the excited waves.

Electromigration Related Effects At Metal-Metal Interfaces: Application To Railguns

DTIC Science & Technology

2007-03-01

found at the armature-rail contact due to local melting, to determine the kinetics of liquid flow Ga under electric current conditions. For this, a...model system comprising a bead of Ga on a Cu thin film track was devised in order to enable liquefaction and current induced movement of Ga to occur...along the Cu track. Upon application of current, Ga underwent liquefaction due to Joule heating and once liquid, it rapidly migrated along the Cu

A crisis in the NASA space and earth sciences programme

NASA Technical Reports Server (NTRS)

Lanzerotti, Louis, J.; Rosendhal, Jeffrey D.; Black, David C.; Baker, D. James; Banks, Peter M.; Bretherton, Francis; Brown, Robert A.; Burke, Kevin C.; Burns, Joseph A.; Canizares, Claude R.

1987-01-01

Problems in the space and earth science programs are examined. Changes in the research environment and requirements for the space and earth sciences, for example from small Explorer missions to multispacecraft missions, have been observed. The need to expand the computational capabilities for space and earth sciences is discussed. The effects of fluctuations in funding, program delays, the limited number of space flights, and the development of the Space Station on research in the areas of astronomy and astrophysics, planetary exploration, solar and space physics, and earth science are analyzed. The recommendations of the Space and Earth Science Advisory Committee on the development and maintenance of effective space and earth sciences programs are described.

Electromagnetic launch of lunar material

NASA Technical Reports Server (NTRS)

Snow, William R.; Kolm, Henry H.

1992-01-01

Lunar soil can become a source of relatively inexpensive oxygen propellant for vehicles going from low Earth orbit (LEO) to geosynchronous Earth orbit (GEO) and beyond. This lunar oxygen could replace the oxygen propellant that, in current plans for these missions, is launched from the Earth's surface and amounts to approximately 75 percent of the total mass. The reason for considering the use of oxygen produced on the Moon is that the cost for the energy needed to transport things from the lunar surface to LEO is approximately 5 percent the cost from the surface of the Earth to LEO. Electromagnetic launchers, in particular the superconducting quenchgun, provide a method of getting this lunar oxygen off the lunar surface at minimal cost. This cost savings comes from the fact that the superconducting quenchgun gets its launch energy from locally supplied, solar- or nuclear-generated electrical power. We present a preliminary design to show the main features and components of a lunar-based superconducting quenchgun for use in launching 1-ton containers of liquid oxygen, one every 2 hours. At this rate, nearly 4400 tons of liquid oxygen would be launched into low lunar orbit in a year.

47 CFR 80.1077 - Frequencies.

Code of Federal Regulations, 2012 CFR

2012-10-01

... System: Alerting: 406.0-406.1 EPIRBs 406.0-406.1 MHz (Earth-to-space).1544-1545 MHz (space-to-Earth). INMARSAT Ship Earth Stations capable of voice and/or direct printing 1626.5-1645.5 MHz (Earth-to-space... safety communications and calling: Satellite 1530-1544 MHz (space-to-Earth) and 1626.5-1645.5 MHz (Earth...

47 CFR 80.1077 - Frequencies.

Code of Federal Regulations, 2013 CFR

2013-10-01

... System: Alerting: 406.0-406.1 EPIRBs 406.0-406.1 MHz (Earth-to-space).1544-1545 MHz (space-to-Earth). INMARSAT Ship Earth Stations capable of voice and/or direct printing 1626.5-1645.5 MHz (Earth-to-space... safety communications and calling: Satellite 1530-1544 MHz (space-to-Earth) and 1626.5-1645.5 MHz (Earth...

47 CFR 80.1077 - Frequencies.

Code of Federal Regulations, 2014 CFR

2014-10-01

... System: Alerting: 406.0-406.1 EPIRBs 406.0-406.1 MHz (Earth-to-space).1544-1545 MHz (space-to-Earth). INMARSAT Ship Earth Stations capable of voice and/or direct printing 1626.5-1645.5 MHz (Earth-to-space... safety communications and calling: Satellite 1530-1544 MHz (space-to-Earth) and 1626.5-1645.5 MHz (Earth...

Electromagnetic wave propagating along a space curve

NASA Astrophysics Data System (ADS)

Lai, Meng-Yun; Wang, Yong-Long; Liang, Guo-Hua; Wang, Fan; Zong, Hong-Shi

2018-03-01

By using the thin-layer approach, we derive the effective equation for the electromagnetic wave propagating along a space curve. We find intrinsic spin-orbit, extrinsic spin-orbit, and extrinsic orbital angular-momentum and intrinsic orbital angular-momentum couplings induced by torsion, which can lead to geometric phase, spin, and orbital Hall effects. And we show the helicity inversion induced by curvature that can convert a right-handed circularly polarized electromagnetic wave into a left-handed polarized one, vice versa. Finally, we demonstrate that the gauge invariance of the effective dynamics is protected by the geometrically induced gauge potential.

Integrating Effective Pedagogies in Science Education with a Design of Alternative Experiments on Electromagnetics

ERIC Educational Resources Information Center

Zhou, Shaona; Yeung, Yau-Yuen; Wang, Yanlin; Wang, Xiaojun; Xiao, Hua

2014-01-01

Learning electromagnetics often involves dealing with problems with strong mathematical skills or thinking about problems in abstract and multiple spaces. Moreover, many students are often unable to explain some related physical phenomena using the appropriate electromagnetic principles. In this paper, we report on integrating two effective…

Seismo-Electromagnetic Emissions Related to Seismic Waves can Trigger TLEs

NASA Astrophysics Data System (ADS)

Sorokin, Leonid V.

2009-04-01

This paper deals with the rare high intensity electromagnetic pulses associated with earthquakes, whose spectrum signature differs from that of atmospherics produced by lightning discharges. On the basis of actual data records, cases of the generation of anomalous seismo-electromagnetic emissions are described. These natural sub-millisecond electromagnetic pulses were associated with the passage of seismic waves from earthquakes to Moscow, the place where the electromagnetic field observations were made. Space-time coupling has been revealed between exact seismic waves from the earthquakes, lightning triggering and Transient Luminous Events triggering.

The Big Bang, Superstring Theory and the origin of life on the Earth.

PubMed

Trevors, J T

2006-03-01

This article examines the origin of life on Earth and its connection to the Superstring Theory, that attempts to explain all phenomena in the universe (Theory of Everything) and unify the four known forces and relativity and quantum theory. The four forces of gravity, electro-magnetism, strong and weak nuclear were all present and necessary for the origin of life on the Earth. It was the separation of the unified force into four singular forces that allowed the origin of life.

Real-time holographic surveillance system

DOEpatents

Collins, H.D.; McMakin, D.L.; Hall, T.E.; Gribble, R.P.

1995-10-03

A holographic surveillance system is disclosed including means for generating electromagnetic waves; means for transmitting the electromagnetic waves toward a target at a plurality of predetermined positions in space; means for receiving and converting electromagnetic waves reflected from the target to electrical signals at a plurality of predetermined positions in space; means for processing the electrical signals to obtain signals corresponding to a holographic reconstruction of the target; and means for displaying the processed information to determine nature of the target. The means for processing the electrical signals includes means for converting analog signals to digital signals followed by a computer means to apply a backward wave algorithm. 21 figs.

Considerations for a Next Generation UV/Optical Space Telescope

NASA Technical Reports Server (NTRS)

Nein, M. E.; Morgan, S. H.

1989-01-01

During the past 25 years, a remarkable scientific revolution, has occurred in astrophysics as a result of convergence on two advancing fronts. First, instruments and telescopes have been developed to make sensitive measurements throughout the entire electromagnetic spectrum. Secondly, access to space has permitted observations above the obscuring and distorting "dirty window" of our atmosphere. Beginning around the middle of the next decade, a third major path - the availability of the permanently manned Space Station Freedom - will join with the earlier two capabilities, to not only continue this revolution, but to accelerate the quest for answers about the universe that have puzzled mankind for centuries. Beyond Earth-orbit, NASA is actively studying the possibility of a return to the Moon, which would provide a valuable platform for astrophysics observations during the next century. The studies discussed in this paper indicate that the technology requirements associated with the transportation to orbit and the assembly of these telescopes in orbit are major driving forces in the selection of generic design concepts. Ultimately, optical advances which are now becoming available through advanced manufacturing must be matched by technology advances in orbital operations, system modularization, and assembly by man and machine.

Spectral Estimation Techniques for time series with Long Gaps: Applications to Paleomagnetism and Geomagnetic Depth Sounding

NASA Astrophysics Data System (ADS)

Smith-Boughner, Lindsay

Many Earth systems cannot be studied directly. One cannot measure the velocities of convecting fluid in the Earth's core but can measure the magnetic field generated by these motions on the surface. Examining how the magnetic field changes over long periods of time, using power spectral density estimation provides insight into the dynamics driving the system. The changes in the magnetic field can also be used to study Earth properties - variations in magnetic fields outside of Earth like the ring-current induce currents to flow in the Earth, generating magnetic fields. Estimating the transfer function between the external changes and the induced response characterizes the electromagnetic response of the Earth. From this response inferences can be made about the electrical conductivity of the Earth. However, these types of time series, and many others have long breaks in the record with no samples available and limit the analysis. Standard methods require interpolation or section averaging, with associated problems of introducing bias or reducing the frequency resolution. Extending the methods of Fodor and Stark (2000), who adapt a set of orthogonal multi-tapers to compensate for breaks in sampling- an algorithm and software package for applying these techniques is developed. Methods of empirically estimating the average transfer function of a set of tapers and confidence intervals are also tested. These methods are extended for cross-spectral, coherence and transfer function estimation in the presence of noise. With these methods, new analysis of a highly interrupted ocean sediment core from the Oligocene (Hartl et al., 1993) reveals a quasi-periodic signal in the calibrated paleointensity time series at 2.5 cpMy. The power in the magnetic field during this period appears to be dominated by reversal rate processes with less overall power than the early Oligocene. Previous analysis of the early Oligocene by Constable et al. (1998) detected a signal near 8 cpMy. These results suggest that a strong magnetic field inhibits reversals and has more variability in shorter term field changes. Using over 9 years of data from the CHAMP low-Earth orbiting magnetic satellite and the techniques developed here, more robust estimates of the electromagnetic response of the Earth can be made. The tapers adapted for gaps provide flexibility to study the effects of local time, storm conditions on Earth's 1-D electromagnetic response as well as providing robust estimates of the C-response at longer periods than previous satellite studies.

The Effect of Guided Note Taking during Lectures on Thai University Students' Understanding of Electromagnetism

ERIC Educational Resources Information Center

Narjaikaew, Pattawan; Emarat, Narumon; Cowie, Bronwen

2009-01-01

This paper reports on the implementation of a guided note taking strategy to promote Thai students' understanding of electromagnetism during a lecture course. The aim of the study was to enhance student learning of electromagnetism concepts. The developed guided notes contain quotations, diagrams, pictures, problems, and blank spaces to encourage…

Real-time wideband cylindrical holographic surveillance system

DOEpatents

Sheen, D.M.; McMakin, D.L.; Hall, T.E.; Severtsen, R.H.

1999-01-12

A wideband holographic cylindrical surveillance system is disclosed including a transceiver for generating a plurality of electromagnetic waves; antenna for transmitting the electromagnetic waves toward a target at a plurality of predetermined positions in space; the transceiver also receiving and converting electromagnetic waves reflected from the target to electrical signals at a plurality of predetermined positions in space; a computer for processing the electrical signals to obtain signals corresponding to a holographic reconstruction of the target; and a display for displaying the processed information to determine nature of the target. The computer has instructions to apply Fast Fourier Transforms and obtain a three dimensional cylindrical image. 13 figs.

The Geopause

NASA Technical Reports Server (NTRS)

Moore, T. E.; Delcourt, D. C.

1995-01-01

Coupled to the Earth and protected by the geomagnetic field, terrestrial matter in the plasma state dominates a larger region of space than was suspected when the 'space age' began, a region we refer to as the geosphere. Accelerated and heated by solar wind energy, this matter expands in size and increases in mass density in response to the Sun's ultraviolet spectrum, heliospheric conditions, and the occurrence of severe space storms. Such storms regularly damage spacecraft, interfere with communications, and trigger power grid interruptions or failures. They occur within the geopause region, that is, the volume defined by the limits of the instantaneous boundary between plasmas that are primarily heliospheric and geospheric. The geopause is analogous in some ways to the heliopause but also resembles the terrestrial air-sea interface. It is the boundary layer across which the supersonically expanding solar plasma delivers momentum and energy to the terrestrial plasma and gas, exciting them into motion, 'evaporating' them into space, and dissipating considerable amounts of power in thermal forms, while generating energetic particles through repeated storage and explosive release of electromagnetic energy. The intensity of the solar wind and the orientation of its magnetic field jointly control the strength of the coupling between solar and terrestrial plasmas and hence the occurrence of severe storms in the geopause region.

Potential aerospace applications of high temperature superconductors

NASA Technical Reports Server (NTRS)

Selim, Raouf

1994-01-01

The recent discovery of High Temperature Superconductors (HTS) with superconducting transition temperature, T(sub c), above the boiling point of liquid nitrogen has opened the door for using these materials in new and practical applications. These materials have zero resistance to electric current, have the capability of carrying large currents and as such have the potential to be used in high magnetic field applications. One of the space applications that can use superconductors is electromagnetic launch of payloads to low-earth-orbit. An electromagnetic gun-type launcher can be used in small payload systems that are launched at very high velocity, while sled-type magnetically levitated launcher can be used to launch larger payloads at smaller velocities. Both types of launchers are being studied by NASA and the aerospace industry. The use of superconductors will be essential in any of these types of launchers in order to produce the large magnetic fields required to obtain large thrust forces. Low Temperature Superconductor (LTS) technology is mature enough and can be easily integrated in such systems. As for the HTS, many leading companies are currently producing HTS coils and magnets that potentially can be mass-produced for these launchers. It seems that designing and building a small-scale electromagnetic launcher is the next logical step toward seriously considering this method for launching payloads into low-earth-orbit. A second potential application is the use of HTS to build sensitive portable devices for the use in Non Destructive Evaluation (NDE). Superconducting Quantum Interference Devices (SQUID's) are the most sensitive instruments for measuring changes in magnetic flux. By using HTS in SQUID's, one will be able to design a portable unit that uses liquid nitrogen or a cryocooler pump to explore the use of gradiometers or magnetometers to detect deep cracks or corrosion in structures. A third use is the replacement of Infra-Red (IR) sensor leads on Earth Orbit Systems (EOS) with HTS leads. IR detectors on these EOS missions are cooled to a 4.2K to improve their signal to noise ratio. They are connected to data acquisitions systems using manganin wires (low thermal conductors) to reduce the heat load on the cryogen. Replacing these wires with HTS leads will increase the lifetime of these missions by about 50 percent. This is a promising application that is ready for actual implementation on such systems. The analysis also show that an the number of IR detectors increase in larger EOS systems, substantial increase in the lifetime of each mission will be realized by using HTS leads instead of the manganin ones.

The Sun-Earth connect 2: Modelling patterns of a fractal Sun in time and space using the fine structure constant

NASA Astrophysics Data System (ADS)

Baker, Robert G. V.

2017-02-01

Self-similar matrices of the fine structure constant of solar electromagnetic force and its inverse, multiplied by the Carrington synodic rotation, have been previously shown to account for at least 98% of the top one hundred significant frequencies and periodicities observed in the ACRIM composite irradiance satellite measurement and the terrestrial 10.7cm Penticton Adjusted Daily Flux data sets. This self-similarity allows for the development of a time-space differential equation (DE) where the solutions define a solar model for transmissions through the core, radiative, tachocline, convective and coronal zones with some encouraging empirical and theoretical results. The DE assumes a fundamental complex oscillation in the solar core and that time at the tachocline is smeared with real and imaginary constructs. The resulting solutions simulate for tachocline transmission, the solar cycle where time-line trajectories either 'loop' as Hermite polynomials for an active Sun or 'tail' as complementary error functions for a passive Sun. Further, a mechanism that allows for the stable energy transmission through the tachocline is explored and the model predicts the initial exponential coronal heating from nanoflare supercharging. The twisting of the field at the tachocline is then described as a quaternion within which neutrinos can oscillate. The resulting fractal bubbles are simulated as a Julia Set which can then aggregate from nanoflares into solar flares and prominences. Empirical examples demonstrate that time and space fractals are important constructs in understanding the behaviour of the Sun, from the impact on climate and biological histories on Earth, to the fractal influence on the spatial distributions of the solar system. The research suggests that there is a fractal clock underpinning solar frequencies in packages defined by the fine structure constant, where magnetic flipping and irradiance fluctuations at phase changes, have periodically impacted on the Earth and the rest of the solar system since time immemorial.

Flux Redux: The Spinning Coil Comes around Again

ERIC Educational Resources Information Center

Lund, Daniel; Dietz, Eric; Zou, Xueli; Ard, Christopher; Lee, Jaydie; Kaneshiro, Chris; Blanton, Robert; Sun, Steven

2017-01-01

An essential laboratory exercise for our lower-division electromagnetism course involves the measurement of Earth's local magnetic field from the emf induced in a rotating coil of wire. Although many methods exist for the measurement of Earth's field, this one gives our students some practical experience with Faraday's law. The apparatus we had…

Levitation Technology in International Space Station Research

NASA Technical Reports Server (NTRS)

Guinart-Ramirez, Y.; Cooley, V. M.; Love, J. E.

2016-01-01

The International Space Station (ISS) is a unique multidisciplinary orbiting laboratory for science and technology research, enabling discoveries that benefit life on Earth and exploration of the universe. ISS facilities for containerless sample processing in Materials Science experiments include levitation devices with specimen positioning control while reducing containment vessel contamination. For example, ESA's EML (ElectroMagnetic Levitator), is used for melting and solidification of conductive metals, alloys, or semiconductors in ultra-high vacuum, or in high-purity gaseous atmospheres. Sample heating and positioning are accomplished through electromagnetic fields generated by a coil system. EML applications cover investigation of solidification and microstructural formation, evaluation of thermophysical properties of highly reactive metals (whose properties can be very sensitive to contamination), and examination of undercooled liquid metals to understand metastable phase convection and influence convection on structural changes. MSL utilization includes development of novel light-weight, high-performance materials. Another facility, JAXA's ELF (Electrostatic Levitation Furnace), is used to perform high temperature melting while avoiding chemical reactions with crucibles by levitating a sample through Coulomb force. ELF is capable of measuring density, surface tension, and viscosity of samples at high temperatures. One of the initial ELF investigations, Interfacial Energy-1, is aimed at clarification of interfacial phenomena between molten steels and oxide melts with industrial applications in control processes for liquid mixing. In addition to these Materials Science facilities, other ISS investigations that involve levitation employ it for biological research. For example, NASA's "Magnetic 3D Culturing and Bioprinting" investigation uses magnetic levitation for three-dimensional culturing and positioning of magnetized cells to generate spheroid assemblies for biomedical applications. Levitation is also used as a modeled microgravity ground analog in the NASA OsteoOmics ISS investigation, which tests whether magnetic levitation accurately simulates microgravity conditions by studying gravitational regulation of osteoblast and osteoclast genomics and metabolism. Elucidating the cellular mechanisms of bone loss in microgravity contributes to the understanding of bone loss in medical disorders on Earth, which may lead to development of preventive or therapeutic countermeasures. Thus, the ISS state-of-the-art laboratory offers various levitation capability platforms with applications for innovative research in Materials and Life Sciences disciplines, with benefits for humanity.

NASA's BARREL Mission in Sweden

NASA Image and Video Library

2017-12-08

The fourth BARREL balloon of this campaign sits on the launch pad shortly before it launched on Aug. 21, 2016. The BARREL team is at Esrange Space Center near Kiruna, Sweden, launching a series of six scientific payloads on miniature scientific balloons. The NASA-funded BARREL – which stands for Balloon Array for Radiation-belt Relativistic Electron Losses – primarily measures X-rays in Earth’s atmosphere near the North and South Poles. These X-rays are produced by electrons raining down into the atmosphere from two giant swaths of radiation that surround Earth, called the Van Allen belts. Learning about the radiation near Earth helps us to better protect our satellites. Several of the BARREL balloons also carry instruments built by undergraduate students to measure the total electron content of Earth’s ionosphere, as well as the low-frequency electromagnetic waves that help to scatter electrons into Earth’s atmosphere. Though about 90 feet in diameter, the BARREL balloons are much smaller than standard football stadium-sized scientific balloons. This is the fourth campaign for the BARREL mission. BARREL is led by Dartmouth College in Hanover, New Hampshire. The undergraduate student instrument team is led by the University of Houston and funded by the Undergraduate Student Instrument Project out of NASA’s Wallops Flight Facility. For more information on NASA’s scientific balloon program, visit: www.nasa.gov/scientificballoons. Credit: NASA/University of Houston/Michael Greer NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

NASA's BARREL Mission in Sweden

NASA Image and Video Library

2017-12-08

The third BARREL balloon floats towards the stratosphere on Aug. 21, 2016. This payload flew for nearly 30 hours, measuring X-rays in Earth’s atmosphere. The BARREL team is at Esrange Space Center near Kiruna, Sweden, launching a series of six scientific payloads on miniature scientific balloons. The NASA-funded BARREL – which stands for Balloon Array for Radiation-belt Relativistic Electron Losses – primarily measures X-rays in Earth’s atmosphere near the North and South Poles. These X-rays are produced by electrons raining down into the atmosphere from two giant swaths of radiation that surround Earth, called the Van Allen belts. Learning about the radiation near Earth helps us to better protect our satellites. Several of the BARREL balloons also carry instruments built by undergraduate students to measure the total electron content of Earth’s ionosphere, as well as the low-frequency electromagnetic waves that help to scatter electrons into Earth’s atmosphere. Though about 90 feet in diameter, the BARREL balloons are much smaller than standard football stadium-sized scientific balloons. This is the fourth campaign for the BARREL mission. BARREL is led by Dartmouth College in Hanover, New Hampshire. The undergraduate student instrument team is led by the University of Houston and funded by the Undergraduate Student Instrument Project out of NASA’s Wallops Flight Facility. For more information on NASA’s scientific balloon program, visit: www.nasa.gov/scientificballoons. Credit: NASA/University of Houston/Michael Greer NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram