D. J. Rodgers

Development of the first artificial comet: UKS ion measurements

On 27 December 1984 the Ion Release Module (IRM) of the AMPTE mission released 1025 barium atoms into the solar wind. The United Kingdom Satellite (UKS) was stationed 170 km away to observe effects on the local plasma for the duration of the resulting artificial comet. One of the most surprising aspects of the results was the subsequent motion of the cloud as observed from the ground. Here we use data from the 3D ion experiment on UKS to examine the momentum flow of the observed barium ions compared to the acceleration of the cloud.

Field-aligned flows of ionospheric plasma in the magnetosphere

Abstract Data are presented from occasions when one of the detectors of the Suprathermal Plasma Analyser on GEOS-2 observed along the magnetic field direction. Electrons were seen with larger fluxes along the field-aligned direction than at 80° to it. One particular class of these events was identified on the night-side when electrons in the energy range 10s to 100s eV were seen. These electrons of ionospheric origin may be associated with suprathermal electron bursts or the permanent power law population of the diffuse auroral zone.