The Cluster mission has provided extremely detailed, multi-point measurements of the cusp and associated surrounding magnetopause regions since August 2000. The nature of the interaction of the solar wind and associated magnetic field, however, benefits from simultaneous coverage over a range of different magnetopause sites. The Cluster polar orbit traversed the dawn-side magnetosphere and flank magnetopause during the April to July 2007 epoch, where the four spacecraft were separated at large distances (10,000 km). In conjunction with this coverage, during the same epoch, the recent launch of the THEMIS mission has placed the five spacecraft initially into a ‘string of pearls’ configuration, all lying on the same equatorial orbit and traversing the low latitude, dusk-side magnetosphere and flank magnetopause. In addition to these 9 spacecraft, the Double star TC-1 spacecraft lies in an equatorial orbit lying between the local times of the THEMIS and Cluster orbits, thereby traversing the dayside magnetopause near local noon. This combination of 10 spacecraft has provided an opportunity to simultaneously monitor the dawn/dusk magnetopause behaviour across the whole range of local times, simultaneously, and to probe any IMF and Solar Wind controlled asymmetries. The distribution and grouping of spacecraft also allow multi-scale analysis of local phenomena operating on both flanks of the magnetopause, such as Kelvin-Helmholtz waves and formation of the plasma sheet. The local time distribution, also in latitude, allows the boundary layer extent to be monitored and simultaneous dawn-dusk tracking of FTEs, the signatures of sporadic reconnection, to be determined. The aim of this proposal is to focus on magnetopause conjunctions, which also link to periods of good coverage from ground base observations. Related aims will be to quantify changes in the structure, thickness and dynamics of the magnetopause boundary layer between the spacecraft locations; correlating these with particular conditions and related magnetospheric response. This work will involve the many instruments onboard each spacecraft, available via the Co-I statuses of the team members. In addition, the extended ground-based facilities, which can provide overall view on the magnetospheric dynamics as well as on the small-scale phenomena, will be used from both northern and southern hemispheres. Moreover, to enhance our understanding of magnetospheric dynamics, MHD simulations for some events will be performed. The conclusion of this study will involve the drafting of a number of papers on the work carried out.

ISSI Proposal (as PDF)