INVESTIGATION OF HORIZONTAL ION DENSITY GRADIENTS IN THE ATMOSPHERE

Abstract

Abstract : The final report is on a satellite measurement program to investigate the characteristics and causes of horizontal ion density gradients in the F- region ionosphere. The report covers the development of the payload, the satellite orbital operations, and the preliminary data analysis phase of the program. The satellite payload was successfully launched on the OV1-18 satellite on 18 March 1969 into a polar orbit with apogee at 590 km and perigee at 469 km. The payload performed generally well throughout the first year's operation although the satellite failed to achieve the desired earthcentered orientation. A large body of generally high-quality flight data has been acquired that promises to yield significant results on the systematic relationships between the ionospheric structure at the satellite altitude and the input energy sources in the form of energetic particle fluxes. Electron density and temperature measurements with a Langmuir probe were acquired during the first 225 orbits. The preliminary data analysis has shown that ionospheric structure is observed and is significant. Computer programs for processing the flight data have been developed and are discussed. The computer programs have been used to perform detailed surveys of the particle fluxes for some early orbits.