The motion and structure of stellar shadow‐band patterns

Abstract

Abstract The structure of stellar shadow bands has been measured on eighteen nights using an optical Fourier analyser technique. The mean size of the pattern elements was found to be 15.6 cm. The measured pattern speed and direction of motion agreed reasonably well with the upper‐air winds in the neighbourhood of 30,000 ft. The lifetime of the shadow‐pattern elements was found to be of the order of tens of milliseconds.