New Concepts in Ionospheric Modification


Book Description

This report considers the ionospheric modification that can be produced by energetic charged particle and photon beams, which are emitted from a platform or vehicle (spacecraft or rockets) located in the ionosphere. The various beams considered include (1) charged particle beams composed of low, moderate, and high energy electrons, (2) beams of ions and plasma, and (3) photon beams of soft X rays and extreme ultraviolet radiation. Briefly considered, in addition to the beam topics, is the ionospheric modification produced by the release of neutral gas of high molecular weight from a rapidly moving vehicle such as the Space Shuttle Orbiter. When a ranking is made in terms of the new information that may be obtained, the scale of the modification that may be produced, and the availability of beam sources, ionospheric modification by means of relativistic electron beams appears particularly promising. However, all the methods have their own distinctive features which could make their use desirable under particular circumstances. The modification produced by means of beams of soft X rays, for example, is not strongly dependent on the beam's direction relative to the earth's magnetic field, and thus modification can be produced in regions inaccessible to a charged particle beam from the same vehicle. Keywords: Ionospheric modification; Particle beams; Electron beams; Photon beams; Plasma beams. (jhd).




An Ionospheric Model for the Arctic


Book Description

A first order approximation model of the Arctic ionosphere is described, based on published observations and concepts. The model allows for modifications and additions whenever new information becomes available, and will eventually represent a true picture available in real time or even as forecast. The location of the phenomena is specified in corrected geomagnetic latitude and local time. Various input parameters are included whenever some of their influences are known, such as UT, seasons, sunspot number, magnetic variations. The Arctic ionospheric features are specified as 'quasi-instant' deviations from routine predictions whereby the devitations represent probabilities of occurrence during periods that may range from 20 min to 3 hr. The following ionospheric features are more or less covered: auroral E (or night-E), auroral Es (or Esr), HF absorption, Arctic F. Necessary improvements to the model are indicated, including the inclusion of storm-time of individual substorms and the requirement that routine observations be maintained in the midnight sector of the auroral oval. (Author).







Spacelab 2


Book Description










Modeling the Ionosphere-Thermosphere


Book Description

Published by the American Geophysical Union as part of the Geophysical Monograph Series, Volume 201. Modeling the Ionosphere-Thermosphere System brings together for the first time a detailed description of the physics of the IT system in conjunction with numerical techniques to solve the complex system of equations that describe the system, as well as issues of current interest. Volume highlights include discussions of: Physics of the ionosphere and thermosphere IT system, and the numerical methods to solve the basic equations of the IT system The physics and numerical methods to determine the global electrodynamics of the IT system The response of the IT system to forcings from below (i.e., the lower atmosphere) and from above (i.e., the magnetosphere) The physics and numerical methods to model ionospheric irregularities Data assimilation techniques, comparison of model results to data, climate variability studies, and applications to space weather Providing a clear description of the physics of this system in several tutorial-like articles, Modeling the Ionosphere-Thermosphere System is of value to the upper atmosphere science community in general. Chapters describing details of the numerical methods used to solve the equations that describe the IT system make the volume useful to both active researchers in the field and students.







Scientific and Technical Aerospace Reports


Book Description

Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.