Short period variations in the N2+(0, 0) auroral emission band represent 5 per cent of the total light in the 3914 A region. These quasi‐periodic coruscations have a dominant period of 6 to 10 seconds. They attain a maximum amplitude in the predawn hours and are closely related to magnetic field micropulsations and ionospheric absorption of cosmic noise. Spectroscopic triangulation showed that the variations originate in theEregion of the ionosphere. The profile of the electron density associated with the aurora was found to have a maximum value of 1.1×104electrons per cubic centimeter at 98 kilomete