Diurnal Variation of Total Electron Content of the Ionosphere Over Nairobi

Abstract

THE ionospheric research station at University College, Nairobi, was set up during 1963 in time to commence observations for the I.Q.S.Y. The station has geographic co-ordinates 36.82° E., 1.32° S. and is 10.5° S. of the magnetic dip equator with a dip of 26.9°. Faraday rotation measurements on the 40-, 41- and 20-Mc/s transmissions from the satellite B.E.–B (S–66) were started on October 10, 1964. This communication presents preliminary values for the diurnal variation of the total electron content I = ∫Ndh for the months of October, November, December 1964, and January 1965, and compares these with median values of (foF2)² obtained from routine vertical incidence soundings at the same station. Due to the rate of precession of the plane of the satellite orbit, the foregoing period of observations represents approximately one complete cycle of I with local time.