MOLECULAR OXYGEN MEASUREMENTS FROM 100 KM TO 150 KM AT WOOMERA, AUSTRALIA

Molecular oxygen distributions in the 100 km to 150 km region have been obtained by u.v. absorption spectroscopy from three Skylark rockets launched at Woomera. These give values well below those forecast by C.I.R.A. 1965 for a period of mean solar activity. The unexpected behaviour of the Ionisation Chambers used as u.v. detectors, at times during all three flights, is described and possible causes suggested. These are principally outgassing from the vehicle and a moisture film on the Ionisation Chamber window. A possible temporary loss of sensitivity due to u.v. between 1500 Å and approximately 2200 Å is also described. © 1969.