1. EGU General Assembly 2006, 2-7 April, 2006, Wien ST6 Multi-point measurements of solar-terrestrial plasma: results and future perspectives Scientific objectives and opportunities during THEMIS mission R. Nakamura, V. Angelopoulos, W. Baumjohann, E. Donovan 1. Overview of THEMIS mission 2. What can we do more if we add Cluster/Ground- based observations (in European sector) to THEMIS ? Acknowledgements: S. Apatenkov, S. Frey, V. Sergeev, O. Amm, A. Grocott, NASA GSFC/SPDF

2. 2 THEMIS TIME HISTORY OF EVENTS AND MACROSCALE INTERACTIONS DURING SUBSTORMS Principal Investigator Vassilis Angelopoulos, UCB Project Manager Peter Harvey, UCB Primary SCIENCE GOAL: “How do substorms operate?” Launch planned in October 2006

3. 3 THEMIS team and instruments Science Team SST ESA EFIa EFIs FGM SCM T spin =3s Probe instruments: ESA: Thermal plasma SST: Super-thermal plasma FGM: Low frequency magnetic field SCM: High frequency magnetic field EFI: Electric field

4. 4 THEMIS Ground observatory (GBO) All-sky imager (ASI) Magnetometer (GMAG) 160 degree hemisphere for the all sky camera

5. 5  Orbits designed for ideal conjunction with GBO Substorm onset locations, THEMIS footprints, and GBO keograms FUV KEOGRAM KIANA 195+/-5 deg. longitude FUV KEOGRAM GILLAM 260+/-5 deg. longitude FUV KEOGRAM GOOSE 295+/- 5 deg. longitude P1 footprints P2 footprints P3,4 footprints P5 footprints [Frey et al., 2005]

6. 6 How do substorm operate ? P1 P2 P3 P4 P5 GBO Flows ? Rarefaction wave ?  Timing between current disruption, reconnection and ground onset withing 30s time resolution  Macroscale Interactions (causal relationship)  Ionospheric coupling THEMIS covers all key regions of a substorm Delineate cause and effect Measure When  Where … and Macroscale Interactions during Substorms (Evolution) Coupling in the magnetosphere Measure plasma flows and waves Coupling to the ionosphere Measure currents and structures

7. 7 Bonus sciences  What produces storm-time “killer” MeV electrons?  What controls efficiency of solar wind – magnetosphere coupling?

8. 8 THEMIS and Cluster Apogee 2007:  Winter: Tail-Cusp  Spring: Dusk-Dawn Flanks  Summer: Tail-LLBL  Fall: Dawn-Dusk Flanks Courtesy MA Hapgood, Rutherford Laboratory,UK What can we do more if we add Cluster/Ground-based observations (in European sector) to THEMIS ?

9. 9 UC Berkeley U Calgary U Saskatchewan EISCAT U Tromso FMI DMI SRI Astronomy North Lancaster U More ground-based stations...

10. 10  Ionospheric disturbances associated with fast flows can be identified as:  Enhanced local convection pattern Experience from Cluster-GB study  Ionospheric/field-aligned current modification [Grocott et al., 2004] [Nakamura et al., 2005]

11. 11 Orbit is designed for North America.. BUT  there are orbits favorable for European sector.  dense ground-based network can be used Cluster1 Cluster4 THEMIS 1 THEMIS 2 THEMIS 5 THEMIS 3 THEMIS 4  Multi-point satellite-ground based studies using THEMIS&Cluster and dense ground-based network can be performed in 2006/2007 winter season Acknowedgement: NASA/SSCWeb

12. 12 Experience from Cluster-DSP study Story may be more complex: Energy dissipation via Alfvén waves? [e.g., Nakamura et al., 2005] THEMIS’s 3D electric field measurements may be able to answer this question as well Evolution of BBF is yet to be understood

13. 13 Cluster perigee observation during BBF  Auroral streamer / injection association  Spatial/temporal properties of injection obtained from multipoint-SC observation AA ABAB B * *** [Apatenkov et al., 2006] “A” associated with dispersed injection at 3:19 “B” could be related to the dispersionless injection

14. 14 3D-observation of BBF evolution  Evolution of BBF can be detected both at low and high-latitude  Electron acceleration/injection process can be monitored THEMIS 2 THEMIS 1 Cluster THEMIS 5 THEMIS 3 Geotail THEMIS 4 X Y  Quantitative estimatation of adiabatic heating during dipolarization [e.g., Apatenkov et al., 2006] can be performed with Cluster/THEMIS [Apatenkov et al., 2006] THEMIS 2007/02/07 Cluster Acknowledgement: NASA/SSCWeb

15. 15 Cluster/DSP/THEMIS conjunction  Plasma entries into the tail from dawnside flank  Low latitude boundary layer dynamics Cluster THEMIS 1 DSP 1 THEMIS 5 THEMIS 2 THEMIS 4 THEMIS 3 Acknowledgement: NASA/SSCWeb

16. 16 Summary  THEMIS (Launch: October 2006) will provide ideal plat forms to study large-scale substorm physics, plasma transport/acceleration processes and solar wind-magnetosphere interaction.  Coordinated observations with Cluster/DSP and dense ground-based observations in European sector will allow even more science returns.