EGU General Assembly 2006, 2-7 April, 2006, Wien EGU General Assembly 2006, 2-7 April, 2006, Wien ST6 Multi-point measurements of solar-terrestrial plasma: results and future ST6 Multi-point measurements of solar-terrestrial plasma: results and future

perspectivesperspectives

Scientific objectives and Scientific objectives and opportunities during THEMIS opportunities during THEMIS

missionmission

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

THEMISTIME HISTORY OF EVENTS AND MACROSCALE INTERACTIONS DURING SUBSTORMS

Principal InvestigatorVassilis Angelopoulos,UCBProject ManagerPeter Harvey, UCB

Primary SCIENCE GOAL:“How do substorms operate?”

Launch planned in October 2006

3

THEMIS team and instrumentsTHEMIS team and instrumentsScience Team

SST

ESA

EFIaEFIs

FGM

SCM

Tspin=3s

Probe instruments:ESA: Thermal plasmaSST: Super-thermal plasmaFGM: Low frequency magnetic fieldSCM: High frequency magnetic fieldEFI: Electric field

5

Orbits designed for ideal conjunction with GBO

Substorm onset locations, Substorm onset locations, THEMIS footprints, and GBO keogramsTHEMIS footprints, and GBO keograms

FUV KEOGRAMKIANA195+/-5 deg. longitude

FUV KEOGRAMGILLAM260+/-5 deg. longitude

FUV KEOGRAMGOOSE295+/- 5 deg. longitude

P1 footprintsP2 footprints

P3,4 footprints

P5 footprints

[Frey et al., 2005]

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How do substorm operate ?How do substorm operate ?

P1P2P3P4P5

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

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THEMIS and ClusterTHEMIS 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 ?

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Ionospheric disturbances associated with fast flows can be identified as:

Enhanced local convection pattern

Experience from Cluster-GB studyExperience from Cluster-GB study

Ionospheric/field-aligned current modification

[Grocott et al., 2004] [Nakamura et al., 2005]

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Orbit is designed for North Orbit is designed for North America.. BUTAmerica.. BUT

there are orbits favorable for European sector.

dense ground-based network can be used

Cluster1

Cluster4

THEMIS 1

THEMIS 2THEMIS 5

THEMIS 3

THEMIS 4

Multi-point satellite-ground based studies using THEMIS&Clusterand dense ground-based network can be performed in 2006/2007 winter season

Acknowedgement: NASA/SSCWeb

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Experience from Cluster-DSP studyExperience from Cluster-DSP studyStory may be more complex: Energy dissipation via Alfvén waves? [e.g., Nakamura et al., 2005]

THEMIS’s 3D electric field measurementsmay be able to answer this question as well

Evolution of BBF is yet to be understood

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Cluster perigee observation during Cluster perigee observation during BBFBBF

Auroral streamer / injection association

Spatial/temporal properties of injection obtained from multipoint-SC observation 0 -101 -1 -2 -3 -4 -5 -6 -7 -8 -9 -11 -12 -13 -14 -15 -16 -17 -18 -19

X gsm , Re

-5

0

5

-6

-4

-3

-2

-1

1

2

3

4

6

Z g

sm,

Re

Geotail

GOES12LANL90

IMAGE

2004/02/23 3 :20-3:30U T XZgsm p lane, fie ld lines T89, Kp=0SC locations are show n: LA N L1990 ---- 0 .5M LT;C luster 1 ,2 ,3,4 --- 0 .8M LT; G O ES12 --- 22M LT; G eota il --- m idn ight

Cluster (in pearl-on-string configuration, 1>3>2>4)

3:15 3:16 3:17 3:18 3:19 3:20 3:21 3:22 3:23 3:24 3:25 3:26 3:27 3:28 3:29 3:30U T

Clu

ster

/RA

PID

and

LA

NL1

990-

095

diff.

ene

rgy

flux,

keV

/(cm

^2 s

r s

keV

)

26-

176

keV

50

-315

keV

3 :15 3:16 3:17 3:18 3:19 3:20 3:21 3:22 3:23 3:24 3:25 3:26 3:27 3:28 3:29 3:30

LAN L

C 1

C 3

C 2

C 4

A A AB

B* * * *

[Apatenkov et al., 2006]

“A” associated with dispersed injection at 3:19

“B” could be related to the dispersionless injection

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3D-observation of BBF evolution3D-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

X gsmZ

gsm

BEQ1

BEQ2

JE(W 1, CL1)

JE(W 1, EQ 1)JE(W 2, EQ 2)

JE(W 2, CL2)

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

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Cluster/DSP/THEMIS conjunctionCluster/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 4THEMIS 3

Acknowledgement: NASA/SSCWeb

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SummarySummary

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.