A Diffraction Theory of the Scintillation of Stars on Optical and Radio Wave-Lengths

A review of current theories of the scintillation of stars on optical wavelengths shows that the refraction theory of scintillation requires excessive atmospheric density gradients, and fails to explain the observed scintillation in colour, whilst the physiological explanations are insufficient to explain all the observed phenomena. A new theory, in which the scintillation phenomena are attributed to Fresnel diffraction at a non-homogeneous atmospheric layer, is shown to explain the observed effects, and to require considerably smaller density gradients. A similar theory, taking into account the. effect of a wave-length change of × 10 7 , is shown to explain the observed fluctuations in intensity of radio waves from the localized extra-terrestrial sources of radio noise.