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The science targets of the SCOPE mission Masaki Fujimoto ISAS, JAXA

The science targets of the SCOPE mission Masaki Fujimoto ISAS, JAXA. The solar system, the natural laboratory for space plasma. Formation of planetary magnetospheres via interaction between the solar wind and the planet’s intrinsic magnetic field

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The science targets of the SCOPE mission Masaki Fujimoto ISAS, JAXA

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  1. The science targets of the SCOPE missionMasaki FujimotoISAS, JAXA

  2. The solar system, the natural laboratory for space plasma • Formation of planetary magnetospheres via interaction between the solar wind and the planet’s intrinsic magnetic field • Dynamics behavior of plasma in the magnetospheres

  3. The same is true for the earth’s magnetosphere • Aurora. Its attractive behavior reflects the dynamism of the plasma in the earth’s magnetosphere

  4. Earth and planetary magnetospheres:The point of view • Interest in itself.

  5. Earth and planetary magnetospheres:The point of view • Interest in itself. • The laboratory of space plasma dynamics • The only field where in-situ measurements of particles and fields can be made.

  6. Magnetospheric physics: The new stage • “The Plasma Universe” • “The Magnetic Universe”

  7. The question What makes the cosmic gas to behave so dynamically? #Looking through the earth’s magnetosphere at the Plasma Universe

  8. Plasmas throughout the Universe

  9. What SCOPE can do to establish the Plasma Universe concept • Perform unprecedented in-situ observations targeted at shocks, reconnection, and turbulence. • The target physical processes are of fundamental importance in the universal context, and are operative in the earth’s magnetosphere. • Construct hands-on-data basis towards the fundamental understanding of the processes. • Critical knowledge that can come only through in-situ observations.

  10. The MHD way of looking at space plasmas • MHD Approximation - Gas motion under the influence of magnetic field and electric currents - The gas motion twists the field lines. - A new spatial distribution of electric currents are set up. - Gas motion is altered. - (refrain)

  11. Electric currents in space • J = rot B in MHD • J is determined by the spatial structure of B. No problem in producing whatever current density required. ??! • J = rot B in MHD • J is determined by the spatial structure of B. No problem in producing whatever current density required.

  12. Electric currents in space • J = rot B in MHD • J is determined by the spatial structure of B. No problem in producing whatever current density required. • In reality, J reflects differential motion between ions and electrons, namely, J=en(Vi-Ve). • A mechanism (non-MHD physics) is needed when extremely large current density (thin current sheet) is required. • Onset of non-MHD effects in a thin current sheet embedded in the MHD-scale dynamics that pinches the current sheet: This is where most of the wonders in space plasmas originate!

  13. Beyond MHD • MHD is useful but misses the most attractive part of space plasma physics • We are determined to step forward and to construct a new framework that truly captures the attraction • SCOPE will generate hands-on-data basis for the new framework.

  14. The only field where detailed in-situ measurements of the complicated physical system is possible

  15. The target physical processesShocks, reconnection, and turbulence:

  16. Shocks • Shocks themselves are fluid-dynamical entities • In space physics, shocks are said to be particle accelerators • Fluid versus particle?! The energy spectrum of cosmic ray

  17. Particle acceleration at shocks ＳＮR１００６

  18. Upstream Fast and cold, Maxwell distribution Downstream Slow and hot, Maxwell distribution Very thin transition layer, where viscosity is effecttive Shocks: ordinary fluid-dynamics versus space plasma physics

  19. Explosive magnetic reconnection

  20. Large scale current sheet pinching motion Thin current sheet foramtion, onset of electron scale dynamics Within it. Maturing of the reconnection engine (diffusion region) Creation of reconnection jet Jet interacting with the surrounding plasma Set-up of auroral current system In the night-side magnetosphere, Production of energetic particles

  21. Theory “predicts” very curious behavior of collisionless plasma. Is it truly happening in the real space plasma? We won’t identify ourselves understanding it until we “see” it in the data.

  22. Turbulence • Turbulence is something you cannot get away from if you are interedted in non-linear fluid/gas dynamics • The addition of the magnetic effects adds even more complication in space plasmas • One of the fundamental problem in space plasma physics, particle acceleration, is closely related with turbulence.

  23. Magnetic field, collisionless system, dynamical coupling among different scales • Cascade  power at short wavelength  viscous dissipation: Ordinary picture • Cascade  power at short wavelength  New terms start to dominate giving rise to new effects: Space plasmas

  24. Space plasma turbulence Power Energy cascase MHD-scale Ion-scale Non-MHD effects arise as cascade proceeds Electron-scale k

  25. Magnetic field, collisionless system, dynamical coupling among different scales • Cascade  power at short wavelength  viscous dissipation: Ordinary picture • Cascade  power at short wavelength  New terms start to dominate giving rise to new effects: Space plasmas • Background (zero-th order) inhomogeneity supported by magnetic field is ubiquitous

  26. Dipole-tail current sheet transition region

  27. Shocks, reconnection, and turbulence MHD phenomenon as a whole. MHD does not let you truly understand what you are attracted to in space plasma physics It is the coupling between MHD-scale dynamics and non-MHD (ion and electron scale physics) that is crucial for the fundamental understanding of space plasma dynamics

  28. What SCOPE can do to establish the Plasma Universe concept • Perform unprecedented in-situ observations targeted at shocks, reconnection, and turbulence. What exactly is this? • Perform unprecedented in-situ observations targeted at shocks, reconnection, and turbulence.

  29. Simultaneousmulti-scale observations

  30. Non-linear effects Non-MHD processes add interesting effects unreachable by MHD dynamics Cross Scale Coupling MHD-scale dynamics Addition of curious effects Large-scale Dynamic phenomenon develops only when the system works as a whole Boundary condition Key process in key region In most cases, ion/electron scale physics

  31. Simultaneous multi-scale measurements • Zoom-in to the electron-scale and monitoring ion/MHD-scale dynamics at the same time # Large FOV and high-resolution pixels at the same time, in the case of imaging.

  32. SCOPE

  33. Shock wave Turbulenceat dipole-current sheet transition region Magnetic Reconnection Boundary Layer Turbulence Processes of fundamental importance in the Plasma Universe

  34. The science questions of SCOPE • Shocks • Reconnection • Turbulence

  35. Shocks • How does a shock dissipate and distribute the upstream kinetic energy? • What is the role of the extended turbulent region upstream of a shock front due to the collision-less nature of the plasma? • How does a shock accelerate particles to high energies?

  36. Reconnection • How is reconnection triggered? • How does the energy conversion in reconnection progress? • How does reconnection produce non-thermal particles?

  37. Turbulence • How does turbulence transport energy over multiple scales? • How does turbulence lead to anomalous transport of plasma? • How does turbulence interact with the background non-uniformity to produce anomalous transport?

  38. The worst question you can ever think of:“Will SCOPE just confirm what theorists predict?”

  39. The key issue: How does the system act locally in response to the requirement J = rot B given by MHD-scale dynamics • Collisionless plasma: Almost infinite degrees of freedom in the distr. fn. shape that satisfies J=en(Vi – Ve) • How Nature makes the choice is the question. • You just cannot convince yourself until you “see the data in your hand”.

  40. Simulation studies and SCOPE • Due to computational resource limitations, one should think that simulation results are suggesting possibilities but nothing more. • At the same time, one should be excited to see in the simulation results how curious space plasmas can possibly behave. • Then one should be motivated to dig into the data to discover that is very exciting, or plan a mission that will produce very exciting data. • Likewise simulation studies are occasionally directed by data analysis studies.

  41. In any case, most simulationists (at least in JP) will invest their efforts in multi-scale simulations for the next ~10 years.

  42. SCOPE: The mission

  43. MHD Scale Electron Scale Ultra high-speed electron measurements Daughter(far)：5km 〜 5000km Daughter(far) Daughter(near)：5km 〜 100ｋｍ Mother Daughter(far) SCOPE-Original Daughter(far)

  44. Mother-NearDaughter pair • As good as/bettter than the MMS s/c • FESA: 10 msec ele detection in the magnetotail (100 times higher sensitivity than MMS) • MEP: Covers 10~100 keV energy range continuously • Wave-particle correlator • Sun-pointing spin axis of ND: Precise measurements of north-south DC E-field component • Inter-s/c distance <100km: Electron-scale pair

  45. FarDaughters • More or less a standard spacecraft (~150kg) • 3-component E&B wave measurements on all s/c enabling quantitative analysis of the wave energy flow • Inter-s/c distance <100km ~ 5000km Electron~ion~MHD scales M-ND pair@electron scale + FD@ion/MHD  simultaneous multi-scale obs.

  46. Obs. supporting systems • Inter-s/c comm. for localization, time-synchronization, commanding, and data link for intelligent coordination • Large volume data storage • Spin axis antenna

  47. Right size budget? • M-ND by JAXA • FD by CSA • SIs onboard SCOPE by JAXA-CSA led consortium • Launcher = H2A: More capability than ISAS science program can afford to fill  NASA as the dual-launch partner

  48. The toughest question • Is the number of the s/c outside the mother-daughter pair, three, good enough? • Two-scales at the same time,at most. • More straightly,more is not only better butis different. International collaboration helps.

  49. The whole picture of SCOPE/Cross-Scale:Full-scale coverage via international collaboration with clear interfaces ESA’s component Cross-Scale To be launched by JAXA’s H2-A SCOPE mother and near/far-daughter (JAXA) Far-daughters (CSA) Dual launch partner THEMIS-like s/c (NASA) China’s component Russia’s component

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