Modification of the ionosphere by large space vehicles

Abstract

A brief history of rocket-induced perturbations upon the upper atmosphere is presented. The theory of formation is described, stressing the role of a rapidly diffusing cloud of highly reactive rocket exhaust molecules interacting with the ionospheric plasma. Computer simulation results of this F-region modification problem show that carefully planned modification experiments can lead to significant advances in our understanding of the near-Earth plasma environment. These modification studies are of particular value in attempts to understand large-scale plasma dynamics, the thermal energy balance of a plasma, and the various modes by which plasma instabilities may be generated on a geophysical scale. The results also demonstrate that the F-region ionosphere will experience significant modification effects with virtually every in-orbit engine burn of the Space Shuttle and the proposed Heavy Lift Vehicles needed to construct Solar Power Satellites. Finally, a method of determining how to maximize (or minimize) ionospheric hole formation is detailed. Introduction A. Background A little over two decades ago, when plans for the International Geophysical Year (IGY) of 1957-58 were underway, it was proposed to launch a small Earth satellite that would carry instruments capable of investigating conditions just outside the Earth's atmosphere (Abell, 1964). While the notion of a top to the terrestrial environment has now been replaced by the concept of earthspace(generally accepted to mean that the Earth's domain as a planet is defined by its magnetosphere) , the spirit to explore that environment has not diminished. An important epoch in the history of human technology occurred on Oct.4, 1957, when Sputnik I marked the first Copyright ©1980 by Michael Mendillo. Published by the American Institute of Aeronautics and Astronautics with permission. Associate Dean, Graduate School, 99 Purchased from American Institute of Aeronautics and Astronautics