Catalogue of Huet auroral spectra 1957-1963

Abstract

The zenith auroral spectra at College, Alaska, obtained during the six observing seasons from the fall of 1957 through the spring of 1963 have been assembled into catalogue form. The prime purpose of this catalogue is to present the auroral activity in a manner which can be used by others in the interpretation of aurorally associated phenomena. From the general appearance of the spectra and other factors a table of daily activity index number (1-9) is given for each observing period. The monthly averages of these index numbers have been plotted for this entire period and compared with various indices of solar and geomagnetic activity. An anomalous increase in the auroral activity index in the fall of 1962 destroys an otherwise perfect trend in the relation of the auroral activity to the decline in the sunspot cycle. It is suggested that a more detailed investigation of both solar and geomagnetic variations is warranted in order to assess the relative contribution of natural and man-made events in producing this anomalous effect.