Add to ORKGThe auroral radiation, 3914 AO, received from the entire sky on a horizontal diffusing plate was monitored continuously during the nights of 1955-56 and 1956-57. The 1955-56 data and part of the 1956-57 data were used to obtain a diurnal curve for the sky luminosity in this wavelength. The auroral light increases to a broad maximum which lasts from magnetic midnight till dawn. The luminosity was found to correlate fairly well with absorption as inferred from F-min values and with (F Eg)2 and very well with the magnetic K indices.The research reported in this document has been sponsored by the Electronic Research Directorate of the Air Force Cambridge Research Center, Air Research and Development Command.Introduction -- I Diurnal Va...