INTERPLANETARY SPACE - Storming Media

Space Environment of Mercury at the Time of the First MESSENGER Flyby: Solar Wind and Interplanetary Magnetic Field Modeling of Upstream Conditions

Oct-2009

10 pages

Authors: Daniel N Baker; Rosemary M Killen; Sean C Solomon; James A Slavin; David Schriver; Jim M Raines; George Gloeckler; Mehdi Benna; C N Arge; Brian J Anderson; Dusan Odstrcil; Thomas H Zurbuchen; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE

The full text of this report is available for sale.

The first flyby of Mercury by the Mercury Surface, Space Environment, Geochemistry and Ranging (MESSENGER) spacecraft occurred on 14 January 2008. In order to provide contextual information about the solar wind (SW) properties and the interplanetary magnetic field near the planet, we have used an empirical modeling technique combined with a numerical physics-based SW model. The Wang-Sheeley-Arge (WSA) method uses solar photospheric magnetic field observations (from Earth-based instruments) in order ...

Studying Geoeffective Interplanetary Coronal Mass Ejections Between the Sun and Earth: Space Weather Implications of Solar Mass Ejection Imager Observations

14-May-2009

26 pages

Authors: D R Mizuno; D F Webb; T A Howard; C D Fry; T A Kuchar; J C Johnston; B V Jackson; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE

Interplanetary coronal mass ejections (ICMEs) are the primary cause of severe space weather at Earth because they drive shocks and trigger geomagnetic storms that can damage spacecraft and ground-based systems. The Solar Mass Ejection Imager (SMEI) is a U. S. Air Force experiment with the ability to track ICMEs in white light from near the Sun to Earth and beyond, thus providing an extended observational range for forecasting storms. We ...

Solar Environmental Disturbances

02 NOV 2007

47 pages

Authors: Richard C. Altrock; Richard R. Radick; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE WEATHER CENTER OF EXCELLENCE

Solar activity refers to a variety of non-thermal phenomena seated in the Sun's outer layers. Many aspects of solar activity exhibit pronounced, and sometimes explosive, temporal variability. The aim of this task has been to explore the basic physics of the sun that leads to the ultimate production of activity. We have investigated processes occurring below the visible surface of the sun, those seen at the visible surface (the photosphere) ...

Solar Rotation, Activity and the Interplanetary Magnetic Field: Forecasting the Strength of the Solar Cycle 24

01-Oct-2007

6 pages

Authors: Roman Brajsa; ZAGREB UNIV (CROATIA) FACULTY OF GEODESY

This report results from a contract tasking Faculty of Geodesy as follows: Present status: A prediction of the strength of future solar cycles is not an easy task (e.g., Wilson, 1994, Solar and Stellar Activity Cycles, Cambridge Univ. Press; Hanslmeier, Denkmayr, and Weiss, 1999, Sol. Phys. 184, 213). There are currently two principal predictions of the strength of the next solar cycle (no. 24). The first one forecasts that the ...

Comprehensive Solar-Terrestrial Environment Model (COSTEM) for Space Weather Predictions

JUL 2007

33 pages

Authors: Tamas I. Gombosi; MICHIGAN UNIV ANN ARBOR

Our team proposed the development of a modular, adaptive, parallel software framework for modeling the Sun-Earth system. The goal of the project was the development of a large-scale model of the solar-terrestrial environment allowing a fuller understanding of space weather and a framework to test theories and investigate the broad implications of new observations. Particular attention was to be devoted to CME formation, propagation, and interaction with the magnetosphere; SEP ...

Advanced Integrated TPS and Non Equilibrium Chemistry Instrumentation

01 JUN 2007

51 pages

Authors: Monika Auweter-Kurtz; Markus Fertig; Georg Herdrich; Michael Winter; STUTTGART UNIV (GERMANY F R)

Upon entering the atmosphere of celestial bodies, spacecraft encounter gases at velocities of more than 10 km/s, thereby being subjected to great heat loads. This makes it necessary to use high temperature thermal protection systems (TPS) to prevent the destruction of the space vehicle. The TPSs as well as the plasma environment during the entry have to be investigated by means of computational and ground facility simulations. The four plasma ...

Nascap-2k Spacecraft-Plasma Environment Interactions Modeling: New Capabilities and Verification

JAN 2007

18 pages

Authors: V. A. Davis; M. J. Mandell; D. L. Cooke; D. C. Ferguson; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE

Nascap-2k is a three-dimensional computer code that models interactions between spacecraft and plasma environments in low-Earth, auroral, geosynchronous, and interplanetary orbits. Previously, we reported on the accuracy of Nascap-2k's charging and current collections calculations by comparing computed currents and potentials with analytic results, and by comparing Nascap-2k results with published calculations using the earlier lower resolution codes, NASCAP/GEO, NASCAP/LEO, and POLAR. Here we examine the accuracy and limitations of two ...

Understanding Magnetic Eruptions in the Sun and Their Interplanetary Consequences

30 APR 2006

4 pages

Authors: George H. Fisher; CALIFORNIA UNIV BERKELEY SPACE SCIENCES LAB

A major goal of our MURI project was to develop a state-of-the-art, observationally- tested 3-d numerical modeling system for predicting magnetic eruptions on the Sun and their interplanetary consequences. This project is motivated by the fact that the Sun drives the most violent space weather events. The mechanisms that trigger and drive these eruptions are the least understood aspects of space weather. A better physical understanding of how magnetic eruptions ...

The IDV Index: Its Derivation and Use in Inferring Long-Term Variations of the Interplanetary Magnetic Field Strength

13 DEC 2005

10 pages

Authors: Leif Svalgaard; Edward W. Cliver; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE

On the basis of a consideration of Bartels' historical u index of geomagnetic activity, we devise an equivalent index that we refer to as the interdiurnal variability (IDV). The IDV index has the interesting and useful property of being highly correlated with the strength of the interplanetary magnetic field (B; R2 = 0.75) and essentially unaffected by the solar wind speed (V; R = 0.01) as measured by spacecraft. This ...

Benefits of Low-Power Stationary Plasma Thruster Propulsion for Small Satellites

28 SEP 2005

16 pages

Authors: Craig W. Clauss; Dennis L. Tilley; David A. Barnhart; ATLANTIC RESEARCH CORP GAINESVILLE VA

The paper examines some of the benefits to gained in using Stationary Plasma Thruster (SPT) propulsion onboard small spacecraft. SPTs were developed in Russia, and have an extensive flight history, with over 70 thrusters flown since 1971. A joint venture company is qualifying a complete propulsion subsystem incorporating Russian thrusters with western electronics and propellant feed components. The availability of thrusters which operate with input powers under 500 watts, as ...

Characteristic Times of Gradual Solar Energetic Particle Events and Their Dependence on Associated Coronal Mass Ejection Properties

01 AUG 2005

10 pages

Authors: Stephen W. Kahler; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE

We use 20 MeV proton intensities from the EPACT instrument on Wind and coronal mass ejections (CMEs) from the LASCO coronagraph on SOHO observed during 1998-2002 to statistically determine three characteristic times of gradual solar energetic particle (SEP) events as functions of solar source longitude: (1) T(sub 0), the time from associated CME launch to SEP onset at 1 AU, (2) T(sub R), the rise time from SEP onset to ...

Characteristic Times of Gradual Solar Energetic Particle Events and Their Dependence on Associated Coronal Mass Ejection Properties

01 AUG 2005

10 pages

Authors: S. W. Kahler; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE

We use 20 MeV proton intensities from the EPACT instrument on Wind and coronal mass ejections (CMEs) from the LASCO coronagraph on SOHO observed during 1998-2002 to statistically determine three characteristic times of gradual solar energetic particle (SEP) events as functions of solar source longitude: (1) T(sub-O), the time from associated CME launch to SEP onset at 1 AU; (2) T(sub-R), the rise time from SEP onset to the time ...

Fusion Reactions and Matter-Antimatter Annihilation for Space Propulsion

13 JUL 2005

42 pages

Authors: Claude Deutsch; CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE ORSAY (FRANCE)

Magnetic confinement fusion (MCF) and inertial confinement fusion (ICF are critically contrasted in the context of far-distant travels throughout solar system. Both are shown to potentially display superior capabilities for vessel maneuvring at high speed, which are unmatched by standard cryogenic propulsion (SCP). Costs constraints seem less demanding than for ground-based power plants. Main issue is the highly problematic takeoff from earth, in view of safety hazards concomitant to ratioactive ...

Relation of Decline Characteristics of 2-4.6 MeV Protons in SEP Events to Solar Wind Parameters

04 JAN 2005

6 pages

Authors: E. I. Daibog; S. Kahler; K. Kecskemety; Y. I. Logachev; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE

The shape of the particle flux decline in solar energetic particle (SEP) events is of particular importance in understanding the propagation of energetic particles in the interplanetary medium. Power-law time profiles indicate the dominance of diffusive propagation, whereas exponential-law decline emphasizes convection transport and adiabatic deceleration. Values obtained theoretically for the decay time in the latter case are reasonably close to the fitted slopes in nearly half of all events ...

Interplanetary CMEs Without Observed Coronagraph CMEs

2005

5 pages

Authors: G. M. Simnett; S. W. Kahler; AIR FORCE RESEARCH LAB HANSCOM AFB MA

The SMEI has observed 88 interplanetary coronal mass ejections (ICMEs) in 2003. This work has established that most of those ICMEs, observed beyond ~30 degrees elongation angles, are associated with bright CMEs with appropriate speeds and position angles observed out to 30 R0(solar) in the SOHO LASCO coronagraph. However, about one quarter of the ICMEs do not have obvious candidate CME associations despite good LASCO observational coverage. We examine the ...

Acceleration and Propagation in the Heliosphere

2005

10 pages

Authors: S. W. Kahler; K. Kecskemety; P. Kiraly; AIR FORCE RESEARCH LAB HANSCOM AFB MA

Heliospheric energetic particles represent a mixture of populations. Sites of original energization of those particles range from solar flares through coronal and interplanetary shocks to distant heliospheric and even galactic sources. Although increasingly sophisticated methods of measuring their energy spectra, composition, charge state, temporal variation and anisotropy help in distinguishing those populations, most studies on particle acceleration and propagation are based on measurements that cannot make such fine distinctions. The ...

The Production of Near-Relativistic Electrons by CME-Driven Shocks

2005

9 pages

Authors: S. W. Kahler; H. Aurass; G. Mann; A. Klassen; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE

The solar sources of near-relativistic (E >30 keV) electron events observed at 1 AU are poorly understood. In general, the solar injection times deduced from the observed 1 AU onset times and assumed 1.2 AU travel distances yield injection times about 10 minutes after the associated flare impulsive phases and type III radio burst times. One interpretation is that the apparent delays occur in the interplanetary medium, probably due to ...

Detailed Dayside Auroral Morphology as a Function of Local Time for southeast IMF Orientation: Implications for Solar Wind-Magnetosphere Coupling

03 NOV 2004

25 pages

Authors: P. E. Sandholt; C. J. Farrugia; W. F. Denig; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE

In two case studies we elaborate on spatial and temporal structures of the dayside aurora within 08:00-16:00 magnetic local time (MLT) and discuss the relationship of this structure to solar wind-magnetosphere interconnection topology and the different stages of evolution of open field lines in the Dungey convection cycle. The detailed 2-D auroral morphology is obtained from continuous ground observations at Ny Alesund (76 deg magnetic latitude (MLAT)), Svalbard during two ...

A Study of the Frequency of Occurrence of Large-Fluence Solar Proton Events and the Strength of the Interplanetary Magnetic Field

02 OCT 2004

15 pages

Authors: K. G. McCracken; G. A. Dreschhoff; D. F. Smart; M. A. Shea; MARYLAND UNIV COLLEGE PARK INST FOR PHYSICAL SCIENCE AND TECHNOLOGY

It has been shown previously that the number of very-large-fluence solar proton events inferred for the period since 1561 were more frequent at times of low solar activity (e.g., following the recovery from the Maunder minimum), than in the present epoch of high solar activity. An inverse dependence is demonstrated between the probability of observation of the very large-fluence solar proton events and the strength of the interplanetary magnetic field ...

Observed and Simulated Depletion Layers with Southward IMF

14 JUN 2004

20 pages

Authors: N. C. Maynard; W. J. Burke; J. D. Scudder; D. M. Ober; G. L. Siscoe; W. W. White; K. D. Siebert; D. R. Weimer; G. M. Erickson; J. Schoendorf; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE

We present observations from the Polar satellite that confirm the existence of two types of depletion layers predicted under southward interplanetary magnetic field (IMF) conditions in magnetohydrodynamic simulations. The first depletion type occurs along the stagnation line when IMF B(X) and/or dipole tilt are/is present. Magnetic merging occurred away from the equator (maynard, et al., 2003) and flux pile-ups developed while the field lines drape to the high-latitude merging sites. ...

Parameterizing the Wind 3DP Heat Flux Electron Data

2004

5 pages

Authors: S. W. Kahler; N. U. Crooker; D. E. Larson; AIR FORCE RESEARCH LAB HANSCOM AFB MA

Solar wind heat flux (HF) electrons are valuable as tracers of the interplanetary magnetic field (IMF) topology, distinguishing positive from negative solar polarities and indicating the presence of magnetically closed CMEs when the flows are counterstreaming. All past applications of heat fluxes to determine field topologies have been based on visual inspection of color spectrograms of electron pitch angle distributions (PADs). However, HF PADs can take a range of shapes ...

Use of Current Data Sets to Depict and Forecast Heliospheric Structure at Earth

05 DEC 2003

38 pages

Authors: Bernard V. Jackson; CALIFORNIA UNIV SAN DIEGO LA JOLLA CENTER FOR ASTROPHYSICS AND SPACE SCIENCES

Solar disturbances produce major effects in the corona, its extension into the interplanetary medium, and ultimately, the Earth's environment. The ability to forecast the arrival at Earth of these disturbances and to determine their effects on the geospace environment is of primary interest to the Air Force, which communicates through and maintains satellites within this environment. It is now understood that the largest of these disturbances, called coronal mass ejections ...

Characterization of the Large-Scale Solar Corona

05 NOV 2003

13 pages

Authors: J. Brosius; CATHOLIC UNIV OF AMERICA WASHINGTON DCDEPT OF PHYSICS

Coronal mass ejections (CMEs) from the Sun constitute one of the primary causes of geomagnetic storms. CMEs also drive shocks, which in turn accelerate solar energetic particles (SEPs) that pose radiation hazards for technological systems in space. With support from AFOSR, researchers from the Catholic University developed an empirical CME arrival (ECA) model that takes as input the CME speed from coronagraph observations and outputs the arrival time of CMEs ...

Probing the Magnetic Polarity Structure of the Heliospheric Current Sheet

13 AUG 2003

10 pages

Authors: S. W. Kahler; N. U. Crooker; D. E. Larson; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE

We use solar wind heat-flux electrons to determine the solar magnetic polarities of the inter-Planetary magnetic field (IMF) close to the heliospheric current sheet (HCS) around the time of the last solar minimum in 1995-1996. At that time the tilt angle of the HCS was very low and solar activity was minimal, allowing the Wind spacecraft-to probe the polarities of the fields close to the HCS during a time relatively ...

Suprathermal Electron Isotropy in High-Beta Solar Wind and Its Role in Heat Flux Dropouts

20 JUN 2003

5 pages

Authors: N. U. Crooker; D. E. Larson; S. W. Kahler; S. M. Lamassa; H. E. Spence; BOSTON UNIV MA CENTER FOR SPACE PHYSICS

Time variations in plasma beta and a parameter which measures isotropy in suprathermal electron pitch angle distributions show a remarkably close correspondence throughout the solar wind. The finding implies that high- beta plasma, with its multiple magnetic holes and sharp field and plasma gradients, is conducive to electron pitch-angle scattering, which reduces heat flux from the Sun without field-line disconnection. Thus the finding impacts our understanding of signatures we use ...

Space Weather Effects: Decay Phases in Gradual and Impulsive Solar Energetic Particle Events

JUN 2003

83 pages

Authors: Vladislav G. Stolpovskii; INSTITUTE FOR NUCLEAR PHYSICS MOSCOW (RUSSIA)

This report results from a contract tasking Skobeltyn Nuclear Physics Institute of Moscow State University as follows: This is an investigation of the decay phases of gradual and impulsive solar energetic particle (SEP) events associated and non-associated to coronal mass ejections (CMEs) and CME-driven shocks. The contractor will use the multispacecraft (mis) data obtained in the 1970s and 1980s to develop understanding of processes of particle transport and losses and ...

Spatial Intensity Gradients of Impulsive Particle Events and Supradiffusive Magnetic Fields

2003

5 pages

Authors: B. R. Ragot; S. W. Kahler; TEXAS UNIV AT AUSTIN DEPT OF ASTRONOMY

The low-energy ion intensity profiles of impulsive solar energetic particle (SEP) events display both sharp (< 2.5 min) local gradients and larger scale ( 1-6 hour) dropouts, indicative of fast crossfield transport on the larger scales in spite of restricted short-scale transport. Rapid variations and modulations within the few-hour long channels of enhanced intensity are also observed. We show that these features are a signature of strong supradiffusion of magnetic ...

Comments on Estimating the Solar Proton Environment that May Affect Mars Missions

2003

6 pages

Authors: D. F. Smart; M. A. Shea; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE

Estimates of the energetic proton environment for a Mars mission are generally extrapolated from the solar proton observations at 1 AU. We find that solar particle events may be divided into two general classes. Events dominated by a near-sun injection of particles onto interplanetary magnetic field lines leading to the spacecraft position represent the "classical" solar particle event associated with solar activity. This class of event will scale in radial ...

Coronal Shocks and Solar Energetic Proton Events

2003

5 pages

Authors: E. W. Cliver; S. W. Kahler; D. V. Reames; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE

From July 1996 - June 2001, 10-1 pr cm-2 s-1 sr-1 MeV-1. Our results are consistent with the following (not mutually exclusive) possibilities: (1) large ^20 MeV SEP events result from strong shocks that call persist well beyond ^3 R.; (2) shock acceleration is most efficient above ^3 R.; (3) shocks that survive to ^3 R. are more likely to have broad longitudinal extents.

The Local Time Dependence of the Anisotropic Solar Cosmic Ray Flux

2003

7 pages

Authors: D. F. Smart; M. A. Shea; AIR FORCE RESEARCH LAB HANSCOM AFB MA

The distribution of the solar cosmic radiation flux over the earth is not uniform, but the result of complex phenomena involving the interplanetary magnetic field, the geomagnetic field and latitude and longitude of locations on the earth. The latitude effect relates to the geomagnetic shield; the longitude effect relates to local time. For anisotropic solar cosmic ray events the maximum particle flux is always along the interplanetary magnetic field direction, ...

Long-Term Trends in Interplanetary Magnetic Field Strength and Solar Wind Structure During the Twentieth Century

17 OCT 2002

9 pages

Authors: I. G. Richardson; E. W. Cliver; H. V. Cane; NATIONAL AERONAUTICS AND SPACE ADMINISTRATION GREENBELT MD GODDARD SPACE FLIGHT CENTER

Lockwood et al (1999) have recently reported a -40% increase in the radial component of the interplanetary magnetic field (IMF) at Earth between 1964 and 1996. We argue that this increase does not constitute a secular trend but is largely the consequence of lower than average fields during solar cycle 20 (1964-1976) in comparison with surrounding cycles. For times after 1976 the average IMF strength has actually decreased slightly. Examination ...

The Cosmic Ray Ground Level Enhancement of 6 November 1997

2002

5 pages

Authors: J. L. Lovell; M. L. Duldig; J. E. Humble; M. A. Shea; D. F. Smart; AIR FORCE RESEARCH LAB HANSCOM AFB MA

The relativistic solar proton event of 6 November 1997 resulted in the first ground-level enhancement (OLE) of solar cycle 23. The earliest onset was around 1215 UT but was up to 15 minutes later at some neutron monitor locations. The time of maximum intensity also varied significantly over the world-wide neutron monitor network. The modeled particle distributions and spectra are presented. The apparent particle arrival direction is found to be ...

Forecasting Heliospheric Structure Using the Solar Mass Ejection Imager (SMEI)

15 AUG 2001

36 pages

Authors: Bernard V. Jackson; Andrew Buffington; P. P. Hick; David F. Webb; CALIFORNIA UNIV SAN DIEGO LA JOLLA CENTER FOR ASTROPHYSICS AND SPACE SCIENCES

Solar disturbances produce major effects in the corona, its extension into the interplanetary medium, and ultimately, the Earth's environment. The ability to forecast the arrival at Earth of these disturbances and to determine their effects on the geospace environment is of primary interest to the Air Force, which communicates through and maintains satellites within this environment. We have developed imaging and other techniques for use in mapping these disturbances (mainly ...

Space Weather Effects: Decay Phases in Gradual and Impulsive Solar Energetic Particle Events

30 MAR 2001

82 pages

Authors: Vladislav G. Stolpovskii; Elena I. Daibog; MOSCOW STATE UNIV (RUSSIA)

This report results from a contract tasking Skobeltsyn Nuclear Physics Institute of Moscow State University as follows: This is an investigation of the decay phases of gradual and impulsive solar energetic particle (SEP) events associated and non-associated to coronal mass ejections (CMEs) and CME-driven shocks. The contractor will use the multispacecraft (m/s) data obtained in the 1970s and 1980s to develop understanding of processes of particle transport and losses and ...

The First S-Ramp Conference, Sapporo, Japan; October 2-6, 2000 - Program

23 OCT 2000

105 pages

Authors: NAGOYA UNIV (JAPAN)

PROGRAM BOOK: Welcome, Message from the President of SCOSTEP, Message from the S-Ramp Steering Committee and the Conveners of the First S-Ramp Conference, and Sapporo Welcomes the First S-Ramp Conference. Additionally, includes General Information, Organizers and Program Committees of Symposial Workshops, Time Schedule, Program, Workshops and Author Index (98 pages). ABSTRACTS: Tutorials: Solar-Terrestrial Physics - Past Achievements and Future Opportunities; Global Circulation of the Middle ...

The First S-Ramp Conference, Sapporo, Japan; October 2-6, 2000 - Abstracts

23 OCT 2000

456 pages

Authors: NAGOYA UNIV (JAPAN)

Radio Sounding of the Magnetopause from the Ground (NIRFI Part)

06 APR 2000

6 pages

Authors: Yuri Tokarev; RUSSIAN ACADEMY OF SCIENCES NIZHNY NOVGOROD RADIO PHYSICAL RESEARCH INST

This report results from a contract tasking Radio Physical Research Institute (NIRFI) as follows: The contractor will investigate whether a high frequency radio pulse transmitted from a ground-based station and backscattered from the magnetopause can be observed in a large receiving antenna.

The Air Force Statistical Auroral Models (AFSAM): Functional Representations

28 JUN 1999

85 pages

Authors: William J. McNeil; RADEX INC BEDFORD MA

We document here the Air Force Statistical Auroral Models (AFSAM), a set of empirical models for average auroral quantities. The quantities include electron and ion integral energy flux, number flux and average energy and the Pedersen and Hall conductivities. These quantities were computed by first computing average electron and ion spectra measured from the DMSP satellites, then converting these average spectra into the several quantities as a function of corrected ...

Hard X-Ray Spectroscopy for Proton Flare Prediction

11 MAR 1999

3 pages

Authors: Frantisek Farnik; CESKOSLOVENSKA AKADEMIE VED PRAGUE

This report results from a contract tasking Academy of Sciences Czech Republic as follows: The contractor will investigate the emission of hard x-rays during solar flare events. The project has two basic goals: 1) to evaluate the efficacy of solar hard x-ray spectroscopy to predict interplanetary proton storms and 2) to study the high energy physics of solar flares.

The Source of the Low Latitude Boundary Layer

3 pages

Authors: Raymond J. Walker; Robert L. Richard; CALIFORNIA UNIV LOS ANGELES INST OF GEOPHYSICS AND PLANETARY PHYSICS

Ion entry into the magnetosphere was studied for different interplanetary magnetic field (IMF) orientations. Field models for the study of ion entry were from the results of global magnetohydrodynamic (MHD) simulations. Ions entering under northward IMF conditions entered on reconnected field lines and entered the flanks of the magnetotail. Some were strongly accelerated during entry at high latitudes. Under southward IMF conditions particles entered through the plasma mantle and only ...

Aerospace Medicine and Biology: A Continuing Bibliography With Indexes

20 OCT 1997

36 pages

Authors: NATIONAL AERONAUTICS AND SPACE ADMINISTRATION HAMPTON VA LANGLEY RESEARCH CENTER

This issue of Aerospace Medicine and Biology, A Continuing Bibliography with Indexes NASA SP-7O11 lists reports, articles, and other documents recently announced in the NASA STI Database. In its subject coverage, Aerospace Medicine and Biology concentrates on the biological, physiological, psychological, and environmental effects to which humans are subjected during and following simulated or actual flight in the Earth's atmosphere or in interplanetary space. References describing similar effects on biological ...

Remote Sensing of Inner Heliospheric Plasmas

AUG 1997

27 pages

Authors: Bernard V. Jackson; CALIFORNIA UNIV SAN DIEGO LA JOLLA

Solar disturbances produce major effects on the corona, the solar wind, the interplanetary medium, and the Earth along with its magnetosphere. New techniques have been developed under this grant for studying plasma disturbances in the inner heliosphere by remotely sensing them. These techniques have used data from the HELIOS spacecraft zodiacal light photometers, in situ data and a variety of other spacecraft and ground based instruments. The ...

The Solar Mass Ejection Imager (SMEI)

19 JUN 97

14 pages

Authors: S. L. Keil; R. C. Altrock; S. W. Kahler; B. V. Jackson; A. Buffington; PHILLIPS LAB HANSCOM AFB MA

The Solar Mass Ejection Imager (SMEI) experiment is designed to detect and measure transient plasma features in the heliosphere, including coronal mass ejections (CMEs), shock waves, and structures such as streamers which corotate with the Sun. SMEI will provide measurements of the propagation of solar plasma clouds and high speed streams which can be used to forecast their arrival at Earth from one to three days in advance. The white ...

Studies of Ionospheric Plasma Electrodynamics

MAY 1997

10 pages

Authors: Roderick A. Heelis; TEXAS UNIV AT DALLAS RICHARDSON WILLIAM B HANSON CENTER FOR SPACE SCIENCES

We have studied features of the high latitude ionosphere that help us to understand the response of the ionosphere-magnetosphere system to changes in the interplanetary medium. These changes begin principally with changes in the large scale ionospheric convection pattern. however, these changes subsequently change the distribution of ionization, which in turn changes the neutral atmosphere and the neutral and plasma temperatures. At high latitudes we have ...

Unfolding The High Energy Electron Flux From CRRES Fluxmeter Measurements

DEC 96

144 pages

Authors: Brian D. McKellar; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING

The Combined Release and Radiation Effects Satellite (CRRES) was launched on 25 July 1990 to collect measurements in the earth's radiation belts. One instrument, the High Energy Electron Fluxmeter (HEEF), measured the flux of electrons in 10 channels with energies between 1 MeV and 10 MeV. The channel sensitivities, Ri(E), have been calibrated and partially re-calibrated. We explore the errors introduced in unfolding the electron flux spectrum from the channel ...

Optimization and Performance Analysis of Waverider Configured Interplanetary Space Vehicles

JUN 96

134 pages

Authors: John M. Flynn; NAVAL POSTGRADUATE SCHOOL MONTEREY CA

This thesis describes a number of issues associated with waverider configured spacecraft designed for interplanetary missions. The first such issue is the determination of the magnitude of the energies and velocities required for conventional gravity-assist (GA) spaceflight maneuvers contrasted with energies and velocities required for less conventional aero-gravity assisted (AGA) maneuvers for interplanetary spaceflight travel These comparisons will be made for an Earth-Mars shuttle mission, a mission to Saturn, a ...

Study of the Origins and Interplanetary Propagation of Geoeffective Disturbances

15 APR 96

177 pages

Authors: John Campbell; Louise Gentile; M. P. Hagan; Stephen Kahler; David Webb; BOSTON COLL CHESTNUT HILL MA INST FOR SCIENTIFIC RESEARCH

This contract has provided a program. of research whose overall goal has been a better understanding of the origins and interplanetary propagation of geomagnetic disturbances and also the dynamics of Solar Energetic Particle events (SEPs). The research built on addressing several areas: the solar eruptive phenomena which lead to sporadic geomagnetic storms; analyses of SEPs to identify particle injection profiles at the Sun; the role of Coronal Mass Ejections (CMEs) ...

Energetic Particles and Magnetic Fields in the Earth's Magnetosphere and Interplanetary Space

03 FEB 96

11 pages

Authors: James A. Van Allen; IOWA UNIV IOWA CITY DEPT OF PHYSICS AND ASTRONOMY

The final technical report is a bibliography of published work supported in whole or in part by the subject grant in magnetospheric physics, cosmic rays and interplanetary energetic particles.

Modeling the Saturnian magnetosphere for the Cassini Mission

1996

40 pages

Authors: Mark D. Skubis; NAVAL ACADEMY ANNAPOLIS MD

This paper presents an advanced, three-dimensional model of the Saturnian magnetosphere. The magnetosphere field of Saturn is the sum of three contributions. The first two contributions, known as interior field sources, are the inherent planetary field and the field due to a co-rotating plasma ring around the planet. The third field contribution results from the interaction of the solar wind with the magnetopause (the magnetospheric boundary). ...

Study of Relationship Between Coronal Mass Ejections and the Electron Component of Solar Energetic Particles

1995

27 pages

Authors: Vladislav G. Stolpovskii; E. I. Daibog; INSTITUTE FOR NUCLEAR PHYSICS MOSCOW (RUSSIA)

This report results from a contract tasking Institute for Nuclear Physics as follows: Investigate the separation of the effects of coronal transport and acceleration on open magnetic field lines, develop a model of the role of CME's in acceleration and escape of nonrelativistic and relativistic electrons.