Visual and radar studies of meteor head echoes

Abstract Simultaneous visual and radar observations of several of the major meteor showers made over 2 decades have been analysed to determine the conditions favourable for meteor head echoes. We find that the probability of getting a head echo depends quite strongly on range and somewhat less so on the brightness of the meteor. We have shown that the scattering area associated with the head echo varies widely even for meteors of a given meteor shower and that the minimum radius of the equivalent reflecting sphere is of the order of 0.8 m. The distribution of the scattering areas associated with the head echo is approximately a truncated power law whose index varies from shower to shower. An explanation based on the composite meteoroid model of Hawkes and Jones (1975, Mon. Not. R. astr. Soc. 173, 339) is proposed.