Observations of the Van Allen radiation regions during August and September 1959: 5. Visual auroras, high-altitude X-ray bursts, and simultaneous satellite observations

Abstract

The measurements made in the outer trapped radiation region by the University of Minnesota ionization chamber and Geiger counter and the scintillation counter furnished by Space Technology Laboratories, Inc., aboard the Explorer 6 earth satellite during the August 16, 1959, magnetic storm are studied. The variations in the detector rates are correlated with the visual aurora recorded by all-sky cameras and with high-altitude X-ray bursts observed by balloon-borne detectors. An increase in radiation observed at a geocentric range of 42,000 km simultaneously with the occurrence of a visual aurora on the electron shell connecting with the satellite measurements suggests that the aurora is associated with a disturbance extending over many degrees of longitude and out to large ranges. Furthermore, a rapid decrease in the Geiger counter rate coincident with a strong low-latitude aurora at Fargo, North Dakota, indicates that energetic radiation is either precipitated out of the outer zone during strong auroras or decelerated by a perturbation of the earth's magnetic field accompanying the aurora. Frequent observations of rate variations at the outer edge of the trapped radiation and at apogee point out the great instability there that results in the frequent discharge of radiation into the atmosphere observed by balloon-borne detectors at the high latitudes connecting with the region. The close correlation of outer-zone intensity variations and solar phenomena indicates that the energy involved in the dynamics of the trapping region has a solar origin.