Journal of Geophysical Research

Simultaneous VHF auroral backscatter measurements


  • Walter A. Flood


Simultaneous auroral echoes at 49.7, 143.5, and 226 Mc/s have been recorded using scaled radar equipments. Analysis indicates that the wavelength dependence of auroral echoes varies from λ3.5 for frequencies of 49.7 and 143.5 Mc/s to λ6.5 for frequencies of 143.5 and 226 Mc/s. These measurements are in reasonable agreement with Booker's theory of auroral echoes if the scale sizes (measured transverse to the magnetic field) are taken as roughly 40 cm. Evidence for nondeviative absorption at 50 Mc/s is also adduced.