Mission Concept

Alfvén will provide the required coordinated two-spacecraft observations within the Auroral Acceleration Region (AAR) several times per day.

From well-designed separations along or across the field lines, during 3 mission phases covering different altitude ranges, ˜90° inclination orbits and with a comprehensive suite of inter-calibrated particles and fields instruments it will measure the variations in particle flux and wave energy that will answer the open questions on energy conversion.

Its imaging will determine how this conversion occurs in a regional context, and its orbit design is ideally suited for resolving the spatio-temporal ambiguities that have plagued previous auroral satellite studies.

Two mission phases measure AAR phenomena on a range of perpendicular and parallel scales respectively, at a range of altitudes.

Tn a third phase, the spacecraft are arranged so as to observe northern and southern hemisphere´s simultaneously, to address questions on large-scale Magnetosphere-Ionosphere coupling.

Andrew Fazakerley and Matthieu Berthomier