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The First Two Years of IMAGE
Jim Burch
Southwest Research Institute
Magnetospheric Imaging Workshop
Yosemite National Park, California
February 5-8, 2002
Outline of Talk
1. Objectives of Magnetospheric Imaging Workshop
2. Summary of IMAGE Accomplishments During Prime Mission
- EUV images of the plasmasphere
- Radio sounding of the plasmasphere
- ENA images of the plasma sheet, ring current, and ionospheric outflow
- FUV images of the proton aurora
3. Introduction to October 21, 2001 Workshop Event
4. Plans for Extended Mission
Objectives of Magnetospheric Imaging Workshop
•Review Accomplishments of IMAGE Prime Mission
•Review Some of the Technological Challenges of IMAGE
•Foster Cooperative Research with Other MagnetosphericMissions, Ground-based Observations, andTheory/Modeling Efforts by Focusing on Specific Events.
•Review Plans for Extended Mission
•Review Plan for the First IMAGE Space Science Update
Plasmasphere Results
IMAGE 304 Å Plasmaspheric Imaging
Observation of Plasmaspheric Tail in Afternoon Sector During a Magnetic Storm at 17:55 UT on August 11, 2000.
Plasmaspheric Shoulders Observed in IMAGE-EUV 304 Å Images
May 24, 2000 09:38 UT July 29, 2000 02:16 UT
Shoulders are Observed to Form in the Dawn Sector Following Northward IMF Turnings and Then Co-Rotate Through the Day Side [Goldstein et al., 2001].
Equipotentials Plasma Density
Formation of Plasmaspheric Shoulder by Northward IMF Turnings [Goldstein et al., 2001]
Formation of Pre-Midnight Trough in Plasmasphere from 04:28 to 13:51 UT on May 9, 2001 [Sandel et al., 2001]
IMAGE 304 Å Plasmaspheric Imaging
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IMAGE 304 Å Plasmaspheric Imaging
Rapid Inward Motion of Nightside Plasmapause During a Substorm at 02:13 to 09:22 UT on July 10, 2000 [Sandel et al., 2001].
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IMAGE-RPI Sounding of the Plasmasphere
Plasmagram traces show both field-aligned echo (blue path) and direct echo (green path) from inside the plasmasphere [Carpenter et al., 2001].
IMAGE-RPI Detection of Source of Kilometric Continuum Radiation[Green et al., 2001]
EUV imager detects “bite outs” in plasmasphere.
RPI data show that kilometric continuum is generated deep within bite outs and is beamed along magnetic equator from a confined source region.
Magnetic Storms and Magnetospheric Substorms
HENA 27-60 keV Ions WIC LBH Aurora Image
06
IMAGE-HENA Images of a Magnetic Dipolarization EventOctober 4, 2000 (09:00 - 10:10 UT) [Brandt, Roelof et al., 2001]
00
18
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IMAGE Observation of a Symmetric Ring Current in Energetic Neutral Atoms [Burch et al., 2001].
[Mitchell et al., 2001]keV
50-60
39-50
27-39
16-27
10-16
3-10
keV
180-222
138-180
96-138
Ionospheric Outflow
Ionospheric Outflow in Response to Solar Wind Pressure Pulses[Fuselier et al., 2001]
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Proton Aurora
FUV-SI Images of Subauroral Proton Arc (Q-Aurora)
Q-Aurora Appears When Main Oval Contracts Following Northward IMF Turning [Burch et al., 2001].
23:50 UT 00:41 UTNov. 10, 2000
Proton Aurora Images of Cusp Response to North-South IMF Transition [Fuselier et al., 2001]
Feasibility of Using Interspacecraft Radio Links to Image Total Electron
Content
IMAGE and WIND Single-Frequency Faraday Rotation Experiment
Aug 15, 2000Orbit Raw Data
• Unducted 828 kHz RPI signal received by WIND/WAVES 6–8 Re distant [Cummer et al., GRL, p. 1131, 2001].
Data Analysis and Interpretation828 kHz RPI Signal Modulation
• Signal modulation gives Faraday rotation
• Single-frequency FR gives relative path-integrated NeB product
Path-IntegratedMagnetospheric
Parameters
Nek•B/kdl) (T/m2)
UT (Aug. 15, 2000)20.2 20.6 21.0
3
2
1
108
T/m2
Some Scientific Accomplishments of IMAGE
• Confirmed Theory of Plasmaspheric Tails
• Discovered New Features of Plasmasphere (Shoulders, Troughs, Cavities, etc.) and Identified Their Causes and/or Effects
• Identified Plasmaspheric Cavities as Source Regions for Kilometric Continuum Radiation
• Clarified Relationships Between Substorms and Magnetic Storms (e.g., O+ Injection into Ring Current Caused by Substorms
• Obtained Global Images of Substorm Dipolarization in the Plasma Sheet
• Discovered Subauroral Proton Arcs and the Role of the IMF in their Formation
• Established Global-Scale Ionospheric Outflow as Immediate Response to Solar-Wind Pressure Pulses
• Demonstrated the Feasibility of Using Interspacecraft Radio Links to Image Total Electron Content
• Obtained the first measurements of solar-wind neutral atoms and interstellar neutral atoms from inside the magnetosphere.
October 21, 2001
Workshop Event
21 October 2001 Geomagnetic Storm: Timeline
21 October 2001 Geomagnetic Storm: Timeline
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21 October 2001 Geomagnetic Storm: Timeline
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Plans for Extended Mission
The extended IMAGE mission focuses on geomagnetic activity during the declining phase of the solar cycle.
The evolution of the IMAGE orbit provides a new, mid- and low-latitude and ultimately southern hemisphere viewing perspective.
Objectives of the IMAGE Extended Mission
Prime Mission(2000-2002)
• solar maximum
• high-latitude, northern hemisphere viewing
Extended Mission(2002-2005)
• declining phase of the solar cycle
• mid- & low-latitude, southern hemisphere viewing
Evolution of IMAGE Orbit During Extended Mission
•Study seasonal and solar cycle variations in solar windneutral flux
•Search for ENAs formed by charge exchange between solar wind ions and interstellar neutrals
•Determine the angular width and start and stop dates of theinterstellar neutral signal observed between late December and early February
Extended Studies of Solar Wind and Interstellar Neutral Atoms