SSL-SWT 1 Aug 6-8, 2007
THEMIS Extended Phase
Summary of THEMIS team discussions(Please note: this is work in progress)
SSL-SWT 2 Aug 6-8, 2007
ARTEMIS
“Acceleration, Reconnection, Turbulence andElectrodynamics of the Moon’s Interaction with the Sun”
ARTEMIS
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What are the important magnetosphericquestions after THEMIS, before MMS?
Distant magnetotail (after Geotail and WIND – single spacecraft)What is the nature and extent of the distant tail neutral line?Does the tail vanish in response to Interplanetary Coronal Mass Ejections?What are the dimensions and topology of plasmoids (carry ½ energy of storms)Answers necessitate multiple THEMIS-type satellites at 0.1-10RE scales
Solar Wind and Shocks (after multiple missions: Cluster, ISEE1/2)How do shocks accelerate particles? (Shock acceleration or diffusion)What is the nature of solar wind turbulence in 1-10RE scale lengths (no data) Answers necessitate multiple THEMIS-type satellites at 1-20RE scales
Lunar Wake (after Lunar Prospector and WIND)What are the plasma waves that make up the nature of the Lunar Wake?How does the wake fill-in from near the moon to far downWhat makes up, sustains and dissipates the electric fields behind the wake Answers necessitate multiple THEMIS-type satellites at 1000-50,000km scales
SSL-SWT 4 Aug 6-8, 2007
ARTEMIS Science Objectives
Acceleration in shocks, tail and lunar environmentWhat is the nature of acceleration at shocks?Follow evolution of particle distributions at two points along the shock.How do MeV electrons get accelerated in the tail?Measure field topology, particle spectra and evolution in time and space.How do energetic (100s of keV) ions and electrons get accelerated in the wake?Measure particles and fields in the wake and the solar wind simultaneously.
ReconnectionWhat is the distant tail reconnection onset mechanism, effects
and response to solar wind drivers?•Spontaneous or induced?•Continuous or impulsive?
Answers necessitate multiple THEMIS-type satellites at 1-20RE scales
Lunar Wake (after Lunar Prospector and WIND)What are the plasma waves that make up the nature of the Lunar Wake?How does the wake fill-in from near the moon to far downWhat makes up, sustains and dissipates the electric fields behind the wake Measure particles and fiels in the wake and outside at 1000-50,000km distance
SSL-SWT 5 Aug 6-8, 2007
ARTEMIS Mission Profile
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ARTEMIS Mission Phases
Phase I (Oct ’09 – Oct ’10) - placement
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ARTEMIS Select Orbits
Phase II (Oct ’10 – Jan ’11) Opposite Sides – Sun-Earth Alignments
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Phase II (Oct ’10 – Jan ’11) Opposite Sides– Dawn-Dusk Alignments
ARTEMIS Select Orbits
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Phase III (Jan ’11 – Apr ’12)Same Side – Sun-Earth Alignments
ARTEMIS Select Orbits
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Phase III (Jan ’11 – Apr ’12)Same Side – Dawn-Dusk Alignments
ARTEMIS Select Orbits
SSL-SWT 11 Aug 6-8, 2007
ARTEMIS Wake Crossings: Phase II,III
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ARTEMIS Wake Crossings: Phase II,III
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ARTEMIS Distant Wake Crossings:A Perspective
B
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Phase IV (Apr ’12 – May ’13)ARTEMIS After Insertion
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ARTEMIS Wake Crossings
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ARTEMIS Ground Operations Concept
DSN, 34mTLM, TRK, CMDTranslunar Orbits
OVRO, 40mTLM Receive Only
BGS, 11mTRK & CMDLunar Orbits
• Flight Dynamics– Translunar Orbit:
• JPL: Mission Design, Orbit Determination, Ephemeris, Maneuver Planning• UCB: Attitude Determination
– Lunar Orbit:• UCB: Mission Design, Orbit/Attitude Determination, Ephemeris, Maneuver Planning
• Mission Operations (UCB)– Pass Scheduling, Mission Planning & Command Generation– Data Trending & Anomaly Resolution, ITOS CMD & Control
• Science Operations (UCB)– Follows Standard THEMIS practices
• Alternate Downlink: OVRO– Refurbishment+Ops: ~1M
– Can track >3hrs/day
– A 40m dish: better than DSN
– Saves government >$10M
SSL-SWT 17 Aug 6-8, 2007
ARTEMIS Science Team
Tail Plasmoids, Scales Slavin, Murphy
Rx/Heating Oieroset, Schriver
Turbulence Weygand, Velli
Acceleration, Scales Slavin, Murphy
Solar Wind Shock acceleration Eastwood, Bale
Turbulence Velli, Weygand
Foreshock Eastwood
Wake Computer sim’s Travnicek, Schriver, Farrell
Laboratory sim’s Gekelman
Exosphere Delory
Refilling, Beams Halekas, Farrell, Bale
SSL-SWT 18 Aug 6-8, 2007
• Senior Review panel– Decides how to apportion funds between continuing missions (Voyager, Cluster …)
– Evaluates and approves plans for FY09/10; hears proposals for FY11/12• THEMIS ends in FY09, would request funding for FY10 and present plan for FY11/12
THEMIS – extension funding request for FY10 with further extension in FY11/12ARTEMIS – proposal to slowly ramp up in FY08/09 and move to operations in FY11/12
• Costs– Cost Guidance would be sufficient to continue THEMIS with minimal operations
• Hinges on scientific publications and discoveries made by THEMIS now• Reviewed on basis of past performance as indicator for future output
– Guest Investigator program to accompany THEMIS extended mission, also possible• Hinges on quality and accessibility of THEMIS data, and community involvement
– Cost increase due to ARTEMIS team and mission operations may necessitate new funds• Senior review panel chair may have to obtain additional funding from Heliophysics director• Received recommendation to proceed with a combined proposal
• Timeline– Proposal due February 21
• Review of Mission Archive Plan: March 2008. Presentations: April 8-11. Selection Jun 12, 2008
THEMIS Extended Phase Proposal