Multi-spacecraft gradient techniques: Applicability for studying magnetosphere-ionosphere coupling

J. De Keyser
Belgian Institute for Space Aeronomy

(invited talk)

In this presentation we review different existing techniques
for computing gradients from multi-spacecraft data, focussing
in particular on least-squares gradient computation. A major
question is: are such techniques useful in the context of the
study of the coupling between the magnetosphere and the ionosphere
in the auroral regions? We discuss the limitations of the methods
and suggest where and how gradient computation is possible.