Auroral electrojet magnetic activity indices

The Auroral Electrojet index (AE) is discussed and a brief description is given of the derivation of 11-station 2.5-minute AE indexes for 1973. Tables are given of hourly average indexes for each day of the year, the stations making the main contribution to the hourly indices, and of the average monthly quiet-time level of horizontal fields (H) at each magnetic observatory. Graphs of the index variations are included for each day of 1973.