A 2972 Å up–down photometer for rocket studies of the aurora

Abstract

A compact photometer for monitoring the total brightness of the O I (3P – 1S) line at 2972 Å along a rocket trajectory, is described. Its use as an aid in separating spatial and temporal changes from altitude variations in auroral intensity is illustrated by an application of the information gathered from such a photometer to the simultaneously measured 5577 Å brightness. An altitude profile of the 5577 Å volume emission rate has been derived showing the lower edge of emission at 112 km and a vertical half-width of 4 km. A 2972/5577 brightness ratio of 0.05–0.08 was measured.