Accession Number : AD0286379

Title :   PRELIMINARY SURVEY OF RESULTS OF OBSERVATIONS OF FIELD-ALIGNED IRREGULARITIES FROM BRISBANE

Corporate Author : QUEENSLAND UNIV BRISBANE (AUSTRALIA)

Personal Author(s) : MATTHEW,EVELYN M.

Report Date : NOV 1961

Pagination or Media Count : 1

Abstract : Preliminary results of an investigation into aspect-sensitive reflections from field-aligned irregularities, undertaken at Brisbane, are discussed. Such echoes were seen to occur at nighttime in the direction of geomagnetic south, with either a U-shape or a patchy appearance. The peak of the diurnal occurrence was at local midnight. The fading rate was generally faster than that of ground back-scatter echoes. Echo durations were usually of the order of 2 hours. The range distribution had a peak of occurrence between 1500 and 1700 km virtual slant range from Brisbane. Range spread along the 180 deg geomagnetic meridian was usually between 100 and 150 km; apparent speeds of motion along this meridian were most commonly less than 200 km/hour. northwards motion predominated before local midnight and southwards after this time. The mean azimuths of observed echoes showed a westward deviation with increasing time, due to ionospheric effects, and also a westw ion with decreasing range. Possible correlatio existed etween echo occurrence radio-star scintillation and sprea F. Som m gnetic control of cho occurrence nd behavior was observed A UTHOR)

Descriptors :   (*RADIO SIGNALS), (*IONOSPHERE), (*SCATTERING), (*STATISTICAL ANALYSIS), (*TERRESTRIAL MAGNETISM), AUSTRALIA

Distribution Statement : APPROVED FOR PUBLIC RELEASE