248
248
May 27, 2011
05/11
by
Gracey, William; Stickle, Joseph W
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eye 248
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Flight tests have been conducted to determine the repeatability of the over-all altimetry errors in the landing-approach condition of two sensitive altimeters (Air Force type C-12) installed in the cockpit of a transport airplane and of four precision altimeters (Air Force type MA-1) installed in a photo-observer. Data were obtained through a speed range of 62 to 100 knots during 42 landing-approach operations conducted on four different days. The results of the tests show that the...
Topics: SOLENOIDS, ELECTROMAGNETIC FIELDS, MAGNETIC FIELD CONFIGURATIONS, ELECTROMAGNETISM, ELLIPTIC...
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194
Jul 12, 2010
07/10
by
NON
texts
eye 194
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No Abstract Available
Topics: PLANETARY MAGNETIC FIELDS, SATURN (PLANET), MAGNETIC FIELD CONFIGURATIONS, PIONEER 11 SPACE PROBE,...
301
301
May 23, 2011
05/11
by
Bullock, Mark A.; Stoker, Carol R.; Mckay, Christopher P.; Zent, Aaron P
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eye 301
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The Viking Gas Chromatograph Mass Spectrometer failed to detect organic compounds on Mars, and both the Viking Labeled Release and the Viking Gas Exchange experiments indicated a reactive soil surface. These results have led to the widespread belief that there are oxidants in the martian soil. Since H2O2 is produced by photochemical processes in the atmosphere of Mars, and has been shown in the laboratory to reproduce closely the Viking LR results, it is a likely candidate for a martian soil...
Topics: MAGNETIC FIELD CONFIGURATIONS, SUNSPOTS, FREE ENERGY, SOLAR FLARES, ELECTRIC CURRENT, X RAYS,...
278
278
May 23, 2011
05/11
by
Tewari, Surendr
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eye 278
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Silicon-base ceramics are promising candidate materials for high temperature structural applications such as heat exchangers, gas turbines and advanced internal combustion engines. Composites based on these materials are leading candidates for combustor materials for HSCT gas turbine engines. These materials possess a combination of excellent physical and mechanical properties at high temperatures, for example, high strength, high toughness, high thermal shock resistance, high thermal...
Topics: MAGNETOPAUSE, MAGNETOHYDROSTATICS, AMPTE (SATELLITES), MAGNETIC FIELD CONFIGURATIONS, CROSSINGS,...
200
200
May 31, 2011
05/11
by
Niiler, Pearn P.; Letelier, Ricardo; Moisan, John R
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In the first part of the project, we investigated the local response of the coastal ocean ecosystems (changes in chlorophyll, concentration and chlorophyll, fluorescence quantum yield) to physical forcing by developing and deploying Autonomous Drifting Ocean Stations (ADOS) within several mesoscale features along the U.S. west coast. Also, we compared the temporal and spatial variability registered by sensors mounted in the drifters to that registered by the sensors mounted in the satellites in...
Topics: HELIOSPHERE, MAGNETIC FIELD CONFIGURATIONS, ULYSSES MISSION, CURRENT SHEETS, MAGNETIC CLOUDS, SOLAR...
234
234
Jun 1, 2011
06/11
by
Erickson, Gary M
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eye 234
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The goal of this project is to determine precursors and signatures of local substorm onset and how they evolve in the plasma sheet using the Geotail near-Earth database. This project is part of an ongoing investigation involving this PI, Nelson Maynard (Mission Research Corporation), and William Burke (AFRL) toward an empirical understanding of the onset and evolution of substorms. The first year began with dissemination of our CRRES findings, which included an invited presentation and major...
Topics: GEOMAGNETIC TAIL, TURBULENCE MODELS, MAGNETOHYDRODYNAMIC TURBULENCE, DIRECT NUMERICAL SIMULATION,...
269
269
May 23, 2011
05/11
by
Lock, James A
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eye 269
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The localized model of the beam-shape coefficients for Gaussian beam-scattering theory by a spherical particle provides a great simplification in the numerical implementation of the theory. We derive an alternative form for the localized coefficients that is more convenient for computer computations and that provides physical insight into the details of the scattering process. We construct a FORTRAN program for Gaussian beam scattering with the localized model and compare its computer run time...
Topics: CHROMOSPHERE, MAGNETIC FIELD CONFIGURATIONS, SUPERGIANT STARS, ROSAT MISSION, COOL STARS,...
299
299
May 23, 2011
05/11
by
Rothermel, Jeffry; Chambers, Diana M.; Jarzembski, Maurice A.; Srivastava, Vandana; Bowdle, David A.; Jones, William D
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Two continuous-wave(CW)focused C02 Doppler lidars (9.1 and 10.6 micrometers) were developed for airborne in situ aerosol backscatter measurements. The complex path of reliably calibrating these systems, with different signal processors, for accurate derivation of atmospheric backscatter coefficients is documented. Lidar calibration for absolute backscatter measurement for both lidars is based on range response over the lidar sample volume, not solely at focus. Both lidars were calibrated with a...
Topics: MAGNETIC FIELD CONFIGURATIONS, POLARITY, HEATING, MAGNETIC FIELDS, MAGNETIC SIGNATURES, MAGNETIC...
204
204
Jul 11, 2010
07/10
by
Basson, D
texts
eye 204
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No Abstract Available
Topics: GEOMAGNETIC TAIL, MAGNETIC FIELD CONFIGURATIONS, MAGNETIC MEASUREMENT, ANNUAL VARIATIONS, EXPLORER...
398
398
Jun 9, 2011
06/11
by
Luckring, J. M
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eye 398
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A 65 degree delta wing has been tested in the National Transonic Facility (NTF) at mean aerodynamic chord Reynolds numbers from 6 million to 120 million at subsonic and transonic speeds. The configuration incorporated a systematic variation of the leading edge bluntness. The analysis for this paper is focused on the Reynolds number and bluntness effects at transonic speeds (M = 0.85) from this data set. The results show significant effects of both these parameters on the onset and progression...
Topics: THIN PLATES, ALUMINUM, COMMERCIAL AIRCRAFT, DEFECTS, NONDESTRUCTIVE TESTS, IMAGING TECHNIQUES,...
280
280
May 6, 2010
05/10
by
Mc Lean, D
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eye 280
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Magnetic field equilibrium configurations in infinite conductive fluid subjected to uniform gravitational field
Topics: CONDUCTIVITY, GRAVITATIONAL FIELD, MAGNETIC FIELD, EQUILIBRIUM, FLUIDS, GRAVITATIONAL FIELDS,...
445
445
Jul 26, 2010
07/10
by
Graham, Robert W
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eye 445
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The possibility that life exists elsewhere in the universe, even in our own planetary system, has intrigued scientists, philosophers, and theologians for centuries. The spaceflight programs of NASA have provided much new information about our planetary neighbors and have put to rest some speculations about the existence of life on those planets or their satellites. However, there are still undetermined questions about the possibility of some form of life existing in the far distant past in our...
Topics: CATHODES, INSERTS, INTERNAL PRESSURE, ORIFICES, CURRENT DENSITY, EROSION, HOLLOW CATHODES, ION...
One of the most important and most puzzling features of the coronal magnetic field is that it appears to have smooth magnetic structure with little evidence for non-potentiality except at two special locations: photospheric polarity inversions lines. (non-potentiality observed as a filament channel) and coronal hole boundaries, (observed as the slow solar wind). This characteristic feature of the closed-field corona is highly unexpected given that its magnetic field is continuously tangled by...
Topics: NASA Technical Reports Server (NTRS), MAGNETIC FIELD CONFIGURATIONS, SOLAR CORONA, SOLAR WIND,...
Nonerupting prominences are not dull, static objects. Rather, they are composed of fine-scale blobs and threads that are highly dynamic, often appearing to travel in opposite directions on adjacent tracks (denoted counterstreaming). Because the plasma is largely constrained to travel along the magnetic field, these cool, dense features can serve as tracers of the prominence magnetic structure, a valuable resource in view of the long-standing difficulty of observing the coronal field....
Topics: NASA Technical Reports Server (NTRS), MAGNETIC FIELD CONFIGURATIONS, SOLAR PROMINENCES, SOLAR...
Magnetic field reconnection at the magnetopause and the energy balance are considered.
Topics: NASA Technical Reports Server (NTRS), INTERNATIONAL SUN EARTH EXPLORERS, MAGNETIC FIELD...
The purpose of this grant was to develop a theoretical understanding of the processes by which open magnetic flux undergoes large-scale transport in the solar corona, and to use this understanding to develop a predictive model for the heliospheric magnetic field, the configuration for which is determined by such motions.
Topics: NASA Technical Reports Server (NTRS), MATHEMATICAL MODELS, HELIOSPHERE, SOLAR CORONA, MAGNETIC...
Magnetic field configurations in which the axial component of the field decays linearly to a constant plateau field are evaluated for use in refocusing the output beam of linear beam microwave tubes. The slope of the decay and the value of the plateau field are parameters in this study. A uniform beam with a space charge force only in the radial direction is assumed, and the electron trajectories are computed for various classes. For a given magnetic configuration (slope and plateau value) the...
Topics: NASA Technical Reports Server (NTRS), ELECTRON BEAMS, FOCUSING, MICROWAVE TUBES, ELECTRON...
We have achieved all the goals stated in our grant proposal in collaboration with Dr. C.C. Wu of the University of California at Los Angeles. Specifically, these include: The understanding of the complexity induced nonlinear spatiotemporal structures and the coexisting propagating modes. The development of plasma resonances and coherent structures in space plasmas. The study of fluctuation-induced nonlinear instabilities and their role in the reconfiguration of magnetic topologies in the...
Topics: NASA Technical Reports Server (NTRS), MAGNETIC FIELD CONFIGURATIONS, NONLINEARITY, PLASMA...
The results of an optimization effort to achieve a minimum weight configuration for a magnetic section circuit (MSC) used in the magnetic portion of a double-focusing mass spectrometer is presented.
Topics: NASA Technical Reports Server (NTRS), DESIGN ANALYSIS, MAGNETIC FIELD CONFIGURATIONS, MASS...
207
207
Jun 2, 2011
06/11
by
Cone, Clarence D., Jr
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eye 207
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The induced drag polar is developed for wt-ngs capable of attaining extremely high loadings while possessing an elliptical distribution of circulation. This development is accomplished through a theoretical investigation of the vortex-wake deformation process and the deduction of the airfoil forces from the impulse and kinetic energy contents of the ultimate wake form. The investigation shows that the induced velocities of the wake limit the maximum lift coefficient to a value of 1.94 times the...
Topics: MAGNETOHYDRODYNAMICS, SOLAR ACTIVITY, SOLAR CORONA, SOLAR MAGNETIC FIELD, MAGNETIC FIELD...
The M2P2 concept is based on the transfer of momentum from the solar wind to an artificial magnetic field structure like that naturally occurs at all magnetized planets in the Solar System, called the magnetosphere. The objectives of this program include the following: (1) Demonstrate artificial magnetospheric inflation through cold plasma filling in vacuum; (2) Demonstrate deflection of a surrogate solar wind by an artificial magnetosphere in the laboratory vacuum chamber; (3) Compare...
Topics: NASA Technical Reports Server (NTRS), MAGNETIC FIELD CONFIGURATIONS, PLASMA PROPULSION, SPACE...
The principal features that might exist in the terrestrial paleoionosphere, if the geomagnetic field were to assume a quadrupole form during a polarity reversal are discussed. Complicated phenomena would be expected to occur at magnetic equators and magnetospherically-driven plasma convection might occur at latitudes where the magnetic field is steeply inclined. The influence of magnetic field strength on ionospheric structure is considered in general terms.
Topics: NASA Technical Reports Server (NTRS), EARTH IONOSPHERE, GEOMAGNETISM, MAGNETIC FIELD...
404
404
May 23, 2011
05/11
by
Bahcall, John; Fisher, Karl; Miralda-Escude, Jordi; Strauss, Michael; Weinberg, Davi
texts
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This grant supported research by the investigators through summer salary support for Strauss and Weinberg, support for graduate students at Princeton University and Ohio State University, and travel, visitor, and publication support for the investigators. The grant originally had a duration of 1 year, and it was extended (without additional funding) for an additional year. The impact of the grant was considerable given its relatively modest duration and funding level, in part because it...
Topics: CURRENT DENSITY, DYNAMIC RESPONSE, POLARITY, CORONAS, MAGNETIC FIELD CONFIGURATIONS, MAGNETIC...
In this final technical report on research funded by a NASA grant, a project overview is given by way of summaries on nine published papers. Research has included: 1) Using suprathermal electron data to study heliospheric magnetic structures; 2) Analysis of magnetic clouds, coronal mass ejections (CME), and the heliospheric current sheet (HCS); 3) Analysis of the corotating interaction region (CIR) which develop from interactions between solar wind streams of different velocities; 4) Use of...
Topics: NASA Technical Reports Server (NTRS), HELIOSPHERE, MAGNETIC FIELD CONFIGURATIONS, ULYSSES MISSION,...
We have achieved all the goals stated in our grant proposal. Specifically, these include: 1. The understanding of the complexity induced nonlinear spatiotemporal coherent structures and the coexisting propagating modes. 2. The understanding of the intermittent turbulence and energization process of the observed Bursty Bulk Flows (BBF's) in the Earth s magnetotail. 3. The development of "anisotropic three-dimensional complexity" in the plasma sheet due to localized merging and...
Topics: NASA Technical Reports Server (NTRS), SPACE PLASMAS, NONLINEARITY, MAGNETIC FIELD CONFIGURATIONS,...
There are eight large bodies in the solar system about which definite statements regarding the existence or nonexistence of a magnetic field of internal origin can now be made. Of these bodies (Sun, Mercury, Venus, Earth, Mars, Jupiter, Saturn, and the Earth's Moon), only Venus and the Moon have negligible surface magnetic fields. By negligible is meant that the magnetic fields are so weak that they do not sensibly perturb the local solar wind. The other bodies provide an interesting zoo of...
Topics: NASA Technical Reports Server (NTRS), MAGNETIC FIELD CONFIGURATIONS, PLANETS, SOLAR WIND,...
Radio noise continuum emissions observed in metric and decametric wave frequencies are, in general, associated with actively varying sunspot groups accompanied by the S-component of microwave radio emissions. These continuum emission sources, often called type I storm sources, are often associated with type III burst storm activity from metric to hectometric wave frequencies. This storm activity is, therefore, closely connected with the development of these continuum emission sources. It is...
Topics: NASA Technical Reports Server (NTRS), MAGNETIC FIELD CONFIGURATIONS, SOLAR MAGNETIC FIELD, SOLAR...
This grant seeks to analyze the Heliospheric Missions data to test current theories on the angular dependence (with respect to mean magnetic field direction) of magnetohydrodynamic (MHD) turbulence in the solar wind. Solar wind turbulence may be composed of two or more dynamically independent components. Such components include magnetic pressure-balanced structures, velocity shears, quasi-2D turbulence, and slab (Alfven) waves. We use a method, developed during the first two years of this...
Topics: NASA Technical Reports Server (NTRS), MAGNETOHYDRODYNAMIC TURBULENCE, MAGNETIC FIELD...
Here researchers report for the first time infrared polarimetry of the normal edge on spiral NGC 4565 and the interacting pair NGC 3690/IC 694 (Arp 299). These observations, as well as previous observations, were made with the Minnesota Infrared Polarimeter on the Space Infrared Telescope Facility during the past year. The goal is to explore the magnetic field geometry in these galaxies and to determine the extent to which the field is ordered and uniform.
Topics: NASA Technical Reports Server (NTRS), GALAXIES, INFRARED RADIATION, INTERSTELLAR MAGNETIC FIELDS,...
In situ observations indicate that the dynamical processes in the geoplasma environment generally entail localized intermittent processes and anomalous global transports. It was suggested by T. Chang that instead of considering the turbulence as a mixture of interacting waves, such type of patchy intermittency could be more easily understood in terms of the development, interaction, merging, preferential acceleration and evolution of coherent magnetic structures. In this three-year project, we...
Topics: NASA Technical Reports Server (NTRS), GEOMAGNETIC TAIL, TURBULENCE MODELS, MAGNETOHYDRODYNAMIC...
The shielding of spacecraft against galactic heavy ions, particularly high-energy Fe(56) nuclei, by electrostatic fields is analyzed for an arrangement of spherical concentric shells. Vacuum breakdown considerations are found to limit the minimum radii of the spheres to over 100 m. This limitation makes it impractical to use the fields for shielding small spacecraft. The voltages necessary to repel these Fe(56) nuclei exceed present electrostatic generating capabilities by over 2 orders of...
Topics: NASA Technical Reports Server (NTRS), ELECTROSTATICS, HEAVY IONS, RADIATION SHIELDING, SPACECRAFT...
A magnetically focused image intensifier was improved to increase the usable range of magnification without degradation of image quality. The power requirements of the focusing coils are minimal. The arrangement of the focusing coils reverses the direction of the axial magnetic field distribution between the planes of the photocathode and the phosphor screen.
Topics: NASA Technical Reports Server (NTRS), IMAGE INTENSIFIERS, MAGNETIC COILS, MAGNETIC FIELD...
The aim of this paper is to evaluate recent observational and theoretical results concerning the physics of chromospheric heating as inferred from IUE, HST-GHRS and ROSAT data. These results are discussed in conjunction with theoretical model calculations based on acoustic and magnetic heating to infer some conclusions about the magnetic and non-magnetic surface structure of cool luminous stars. I find that most types of stars may exhibit both magnetic and nonmagnetic structures. Candidates for...
Topics: NASA Technical Reports Server (NTRS), CHROMOSPHERE, MAGNETIC FIELD CONFIGURATIONS, SUPERGIANT...
This program addresses the evolution of stellar coronas by comparing a solar-like corona in the supergiant Dra (G2 Ib-IIa) to the corona in the allegedly more evolved state of a hybrid star, TrA (K2 11-111). Because the hybrid star has a massive wind, it appears likely that the corona will be cooler and less dense as the magnetic loop structures are no longer closed. By analogy with solar coronal holes, when the topology of the magnetic field is configured with open magnetic structures, both...
Topics: NASA Technical Reports Server (NTRS), STELLAR CORONAS, SUPERGIANT STARS, STELLAR EVOLUTION, CORONAL...
We consider processes occurring just prior to and at the start of the onset of flare- and CME-producing solar eruptions. Our recent work uses observations of filament motions around the time of eruption onset as a proxy for the evolution of the fields involved in the eruption. Frequently the filaments show a slow rise prior to fast eruption, indicative of a slow expansion of the field that is about co explode. Work by us and others suggests that reconnection involving emerging or canceling flux...
Topics: NASA Technical Reports Server (NTRS), EXTREME ULTRAVIOLET RADIATION, MAGNETIC FIELD CONFIGURATIONS,...
327
327
Jun 11, 2011
06/11
by
NON
texts
eye 327
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The topics addressed in the conference paper abstracts contained in this document include: extracting resources from the Moon and Mars, equipment for in situ resource utilization, mission planning for resource extraction, drilling on Mars, and simulants for lunar soil and minerals.
Topics: ELECTRON DENSITY (CONCENTRATION), JOINT EUROPEAN TORUS, ELECTRON ENERGY, PLASMAS (PHYSICS),...
1,331
1.3K
Jul 23, 2010
07/10
by
Yates, E. Carson, Jr
texts
eye 1,331
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To promote the evaluation of existing and emerging unsteady aerodynamic codes and methods for applying them to aeroelastic problems, especially for the transonic range, a limited number of aerodynamic configurations and experimental dynamic response data sets are to be designated by the AGARD Structures and Materials Panel as standards for comparison. This set is a sequel to that established several years ago for comparisons of calculated and measured aerodynamic pressures and forces. This...
Topics: CHROMOSPHERE, SOLAR FLARES, ULTRAVIOLET PHOTOGRAPHY, MAGNETIC FIELD CONFIGURATIONS, PHOTOSPHERE,...
In a magnetic suspension system, accurate force measurement will result in better control performance in the test section, especially when a wider range of operation is required. Although many useful methods were developed to obtain the desired model, however, significant error is inevitable since the magnetic field distribution of the large-gap magnetic suspension system is extremely nonlinear. This paper proposed an easy approach to measure the magnetic torque of a magnetic suspension system...
Topics: NASA Technical Reports Server (NTRS), MAGNETIC SUSPENSION, TORQUE, TORQUEMETERS, VELOCITY...
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253
Jun 12, 2011
06/11
by
Smid, Jan; Obitko, Marek; Fisher, David; Truszkowski, Wal
texts
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Knowledge acquisition and sharing are arguably the most critical activities of communicating agents. We report about our on-going project featuring knowledge acquisition and sharing among communicating agents embedded in a network. The applications we target range from hardware robots to virtual entities such as internet agents. Agent experiments can be simulated using a convenient simulation language. We analyzed the complexity of communicating agent simulations using Java and Easel. Scenarios...
Topics: MAGNETIC FIELD CONFIGURATIONS, CURRENT DENSITY, PARTICLE ACCELERATION, RELATIVISTIC ELECTRON BEAMS,...
A mathematical formalism for modeling the poloidal magnetic field and current density at satellite altitudes is presented.
Topics: NASA Technical Reports Server (NTRS), GEOMAGNETISM, MODELS, POTENTIAL FIELDS, SATELLITE...
Disconnection event (DE) in cometary plasma physics is the regular loss of the entire plasma tail and the growth of the new one. Analysis of a sequence of DEs that occurred 13-18 April, 1986 shows that they correlate well with a magnetic, sector-boundary crossing and a complex magnetic structure in the solar wind with polarity reversals that occurred about one day later. These events are entirely consistent with sunward, magnetic reconnection as the DE mechanism.
Topics: NASA Technical Reports Server (NTRS), COMET TAILS, HALLEY'S COMET, MAGNETIC FIELD CONFIGURATIONS,...
A preliminary report on the identification and optimization of independent variables which affect the ion density and confinement time in a bumpy torus plasma is presented. The independent variables include the polarity, position, and number of the midplane electrode rings, the method of gas injection, and the polarity and strength of a weak vertical magnetic field. Some characteristic data taken under condition when most of the independent variables were optimized are presented. The highest...
Topics: NASA Technical Reports Server (NTRS), ION DENSITY (CONCENTRATION), MAGNETIC FIELD CONFIGURATIONS,...
An analytical model of O-type configurations was derived, for visualizing the geometry and for numerical treatment of plasma flows. It was found that at a certain distance from the neutral line the mean particle motion became decoupled from that of magnetic field lines (which obey the MHD condition). The decoupling distance depended on initial conditions in momentum space, suggesting that the MHD approximation which averages out such conditions may not suffice for describing plasma dynamics...
Topics: NASA Technical Reports Server (NTRS), EARTH MAGNETOSPHERE, MAGNETIC STORMS, NEUTRAL SHEETS, SOLAR...
We study the rotational distortions of the vacuum dipole magnetic field in the context of geometrical models of the radio emission from pulsars. We find that at low altitudes the rotation deflects the local direction of the magnetic field by at most an angle of the order of r(sup 2 sub n), where r(sub n) = r/R(sub lc), r is the radial distance and R(sub lc) is the light cylinder radius. To the lowest (i.e. second) order in r(sub n) this distortion is symmetrical with respect to the plane...
Topics: NASA Technical Reports Server (NTRS), PULSAR MAGNETOSPHERES, STELLAR ROTATION, RADIO EMISSION,...
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171
May 6, 2010
05/10
by
Tsap, T. T
texts
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Magnetic field and fine structure of chromosphere in active region of sun
Topics: CHROMOSPHERE, CHROMOSPHERE, FINE STRUCTURE, SOLAR MAGNETIC FIELD, SUN, FINE STRUCTURE, H ALPHA...
The inclusion of adequate versatility into the electromagnet array configuration requires sizing the electromagnets to satisfy particular absolute force and moment requirements. Magnetic performance of a permanent magnet model core, air cored electromagnet may easily and reliably be computed by using the FORCE program which calculates model forces and moments via representations of the model as an assembly of dipoles and the electromagnets as an assembly of line currents. Some aspects of the...
Topics: NASA Technical Reports Server (NTRS), ATTITUDE CONTROL, ELECTROMAGNETS, MAGNET COILS, MAGNETIC...
We report on the dynamics of the small-scale solar magnetic field, based on analysis of very high resolution images of the solar photosphere obtained at the Swedish Vacuum Solar Telescope. The data sets are movies from 1 to 4 hr in length, taken in several wavelength bands with a typical time between frames of 20 s. The primary method of tracking small-scale magnetic elements is with very high contrast images of photospheric bright points, taken through a 12 A bandpass filter centered at 4305 A...
Topics: NASA Technical Reports Server (NTRS), SOLAR MAGNETIC FIELD, MAGNETIC FIELD CONFIGURATIONS,...
A novel method is described for reconstruction of two-dimensional current-layer structures from measurements taken by a single spacecraft traversing the layer. In its present form, the method is applicable only to 2D magnetohydrostatic structures that are passively convected past the observing spacecraft. It is tested on a magnetopause crossing of the tangential-discontinuity type by the spacecraft AMPTE/IRM. The magnetic structures recovered include a magnetic island located between two X-type...
Topics: NASA Technical Reports Server (NTRS), MAGNETOPAUSE, MAGNETOHYDROSTATICS, AMPTE (SATELLITES),...
In the open magnetosphere model magnetic field lines from the polar caps connect to the interplanetary magnetic field and conduct an electric field from interplanetary space to the polar ionosphere. By examining the magnetic flux involved it is concluded that only slightly more than half of the magnetic flux in the polar caps belongs to open field lines and that such field lines enter or leave the magnetosphere through narrow elongated windows stretching the tail. These window regions are...
Topics: NASA Technical Reports Server (NTRS), EARTH MAGNETOSPHERE, ELECTRIC FIELDS, MAGNETIC FIELD...
ASCA (Advanced Satellite for Cosmology and Astrophysics) and EUVE (Extreme Ultraviolet Explorer) spectra of active late-type stars imply that Fe and other medium-Z elements may be 2-10 times less abundant in the coronae of these stars than in their photo-spheres (the MAD effect). These deficiencies may be related to the solar FIP (First Ionization Potential) effect, in which Fe and other low First Ionization Potential elements appear enriched in the solar corona over their photospheric values....
Topics: NASA Technical Reports Server (NTRS), X RAY ASTRONOMY, STELLAR CORONAS, STELLAR SPECTRA, MAGNETIC...
