Published online by Cambridge University Press: 25 April 2016
The fact that Jupiter’s inner magnetosphere is not axially symmetric was originally demonstrated by ground-based radio measurements. Departures from symmetry are evident in the pattern of bursts occurring at decametre wavelengths and also in the characteristics of the polarized synchrotron emission observed at decimetre wavelengths. Direct measurements of Jupiter’s magnetic field, made from the Pioneer space probes, also indicate departures from an axially symmetric configuration.