In:
Annales Geophysicae, Copernicus GmbH, Vol. 22, No. 7 ( 2004-07-14), p. 2577-2585
Abstract:
Abstract. The electron density profiles derived from the EFW and WHISPER instruments on board the four Cluster spacecraft reveal density structures inside the plasmasphere and at its outer boundary, the plasmapause. We have conducted a statistical study to characterize these density structures. We focus on the plasmasphere crossing on 11 April 2002, during which Cluster observed several density irregularities inside the plasmasphere, as well as a plasmaspheric plume. We derive the density gradient vectors from simultaneous density measurements by the four spacecraft. We also determine the normal velocity of the boundaries of the plume and of the irregularities from the time delays between those boundaries in the four individual density profiles, assuming they are planar. These new observations yield novel insights about the occurrence of density irregularities, their geometry and their dynamics. These in-situ measurements are compared with global images of the plasmasphere from the EUV imager on board the IMAGE satellite.
Type of Medium:
Online Resource
ISSN:
1432-0576
DOI:
10.5194/angeo-22-2577-2004
Language:
English
Publisher:
Copernicus GmbH
Publication Date:
2004
detail.hit.zdb_id:
1458425-6
Permalink