Additional results from an Ogo 6 Experiment concerning ionospheric electric and electromagnetic fields in the range 20 Hz to 540 kHz

Abstract

Ogo 6 was launched on June 5, 1969, into a polar orbit with a perigee of 400 km and an apogee of about 1100 km; normal Ogo 6 operations were terminated on June 28, 1971. Our experiment on the spacecraft yielded real time analog data in four 15-kHz bands (20 Hz to 15 kHz, 15–30 kHz, 92.5–107.5 kHz, and 280–295 kHz), and tape-recorded digital data in two 200-Hz bands (200 kHz and 540 kHz), and from a broad band intensity detector. The experiment sensor consisted of an electric dipole with a tip-to-tip length of about 24 meters. This paper summarizes those findings from the experiment that have not been published previously. These include the following: (1) an observation of emissions triggered by proton whistlers, (2) numerous clear examples of whistler-associated lower hybrid resonance (LHR) noise, (3) new results on the auroral hiss zone and on its relation to the high-altitude polar cusp, and (4) new results on emissions triggered by VLF stations, which point to a similarity between whistler precursors and triggered emissions, suggesting a similarity in the generation mechanisms.