Browsing GI Reports by Author "Cronin, Harold"
Zenith night sky light measurements at College, AlaskaWilcox, John B.; Kohls, Fred F.; Cronin, Harold (University of Alaska. Geophysical Institute., 1950-06-30)For purposes of studying the character of time fluxuations in arctic night sky brightness, we have erected a photoelectric monitory system at the Ballaine’s Lake Field Station (latitude N64°52', longitude W147°49'). The unit was set in operation September 27, 1949, and dismounted June 6, 1950, when it became evident that further observations would be impossible due to lengthening days. Although no apparatus has been available by which the response curves of phototubes could be calibrated absolutely, a standard by which bright ness recordings of different phototubes can be reduced to approximate absolute values has been evolved. A limited investigation of a possible correlation between fluxuations in the intensity of upper atmospheric emissions and sporadic conditions in the ionosphere has been made.