Excerpt:
Incoherent scatter studies have been conducted at Millstone Hill since 1960. J. J. Thomson had shown in 1906 that electrons are capable of scattering electromagnetic waves of any frequency, but because of the very small cross section for this kind of scattering it was long thought that incoherent or Thomson scatter from ionospheric electrons was not detectable. However, in 1958 W. E. Gordon demonstrated that with a sufficiently large antenna and high-powered radar system this scattering should be detectable