Attempt to measure night helium glow-Evidence for metastable molecules in the night ionosphere

Abstract

An Aerobee rocket flown from White Sands Missile Range at 1115 UT, November 29, 1960, included a first experimental attempt to measure the intensity of the helium glow in the night sky. The experiment has provided evidence that the brightness of this glow is less than one tenth the brightness of the night Lyman α glow. The photoelectric detector produced signals that may be interpreted as evidence that a supply of metastable molecules exists in the night ionosphere at altitudes above 100 km.