On the effect of the partial solar eclipse of 29 April 1976 on electron content

Abstract

Faraday rotation measurements made at a chain of stations and group delay measurements made at Ootacaraund from ATS-6 are examined for the partial solar eclipse event of 29 April 1976. There is no evidence of eclipse-induced gravity waves in these measurements extending from Ootacamund near dip equator to Patiala (dip45~ Eclipse-induced fluctuations wear however reported at Trivandrura, about 300 km south of Ootacamund.

Temperature variation in the mesosphere during solar eclipse

“…From observations of Faraday rotation and group delay measurements at 40 MHz using radio beacons from ATS-6 at Trivandrum, Vaidyanathan et al (1978) had reported quasi-periodic fluctuations of about l0 min periodicities during the partial eclipse of 29 April 1976. However, Sethia et al (1980) using the ATS-6 satellite data for a number of other locations for the same eclipse reported absence of travelling ionospheric disturbances at all these stations. Thus we see that the presence/absence of eclipse-induced gravity waves is still highly controversial…”