THEMIS SCIENCE WORKING TEAM MEETING Mission Overview Peter

THEMIS SCIENCE WORKING TEAM MEETING Mission Overview Peter R. Harvey Project Manager University of California - Berkeley SWT Overview 1 UCB, Nov 15/16, 2006

Mission Summary Mission Parameters • Launch Vehicle: Apogee: Perigee: Inclination: Date: Delta II, Eastern Range 84191 km ± 9567 km 400 km ± 6 km 17. 0 deg ± 0. 5 deg Feb 15, 2007 • Space Segment Spacecraft: 5 Spinning Probes with Fuel for Orbit & Attitude Adjust Instruments: 3 -Axis Electric Field, Magnetic Field 3 -D Ion & Electron Particle Detectors Spin Rate: 20 RPM Orbit Period(s): 1, 2 and 4 days Orientation: Ecliptic Normal • Ground Segment Observatories: Control Facilities: 20 Northern with All Sky Imagers and Magnetometers Mission and Science Operations Centers • Operations Phases: Lifetime: SWT L&EO, Cruise, Ascent, Campaigns, De-orbit 2. 3 years Overview 2 UCB, Nov 15/16, 2006

Instrument Configuration IDPU: Instrument Data Processor Unit SPB : Spin Plane Booms (4 x) AXB : Axial Booms (2 x) SST : Solid State Telescope (2 x) ESA : Electrostatic Analyzer FGM : Fluxgate Magnetometer SCM : Search Coil Magnetometer SWT Overview 3 UCB, Nov 15/16, 2006

Probe Configuration EFI Axial Booms (2, Stowed) Antenna ESA Miniature Sun Sensor Fuel Tank IDPU EFI SPB Thruster A 2 Repress Tank Fuel Tank Transponder Thruster T 1 EFI SPB Thruster A 1 BAU Battery Gyros Thruster T 2 SWT AEB Overview 4 EFI SPB UCB, Nov 15/16, 2006

Launch Configuration Dedicated launch accommodated within standard Delta 7925 -10 vehicle configuration and services 10’ Composite Fairing required to accommodate five Probes on the Probe Carrier in the “Wedding Cake” configuration PC stays attached to Delta 3 rd stage after probe dispense Each probe dispense from the PCA is coordinated with but independent of the other probes No single probe anomaly precludes dispense of remaining probes Standard Delta 10 ft. Fairing Static Envelope Probe Carrier Assembly (PCA = 5 Probes + Probe Carrier) on L/V 3712 PAF Star 48 3 rd Stage Probe Carrier Assembly (PCA) on Delta 3 rd Stage THEMIS Launch Configuration SWT Overview 5 UCB, Nov 15/16, 2006

Probe & PC Status Probe Status Environmental Tests June 28 2006 SWT Overview 6 UCB, Nov 15/16, 2006

Probe & PC Status Probes 1 to 5 LPTs PC & Mass Dummies July 5 -7 2006 SWT Overview 7 UCB, Nov 15/16, 2006

Probe & PC Status PCA Assembly and Test, July 10 -11 2006 SWT Overview 8 UCB, Nov 15/16, 2006

Probe & PC Status PCA Vibration, July 12 -14 2006 SWT Overview 9 UCB, Nov 15/16, 2006

Probe & PC Status Probe/PC Testing at JPL, July 17 -23 2006 Probes 1 and 5 are Spin-Balanced and Magnetically Tested Probes 3 and 4 Prepare for Thermal Vacuum SWT Probe 2 and PC get boxed up Overview 10 UCB, Nov 15/16, 2006

Probe & PC Status Probe. Testing at JPL, July 24 -Aug 7 2006 Probes 3 and 4 Removal from TV Probes 3 and 4 Arrive at SAF SWT Probes 3 and 4 Transport to SAF Probes 3 and 4 Mag Testing Overview 11 UCB, Nov 15/16, 2006

Probe & PC Status Probe Testing at JPL, thru Aug 28 2006 Probe 1 on Rollover Fixture for ESA Probes 1 and 5 Removal from TV Probes 1 and 5 Transport to SAF SWT Probes 1 -Final 5 at Rest Balance in SAF Overview 12 UCB, Nov 15/16, 2006

Probe & PC Status Probe Testing at JPL, thru Aug 28 2006 Probe 1 on Rollover Fixture for ESA Probes 1 and 5 Removal from TV Probes 1 - 5 at Rest in SAF Probes 1 and 5 Transport to SAF Probes 1 - 5 at Rest in SAF SWT Overview 13 UCB, Nov 15/16, 2006

Probe & PC Status EFI Preamp Current Issue (PFR 181 a) q q q q Historic Current Variations in EFI Preamps 3 -10 m. A Pre. Ship Review Team Requested More Tests Extended Vacuum Testing on FM 6 hit 20 m. A (red limit) Determined Reversed Polarity Caps (on silkscreen) Manufacturer Allows 10 -15% reverse bias EFI Preamps Use 20% reverse bias Lifetime severely limited in reversed polarity. Expected to fail prior to primary mission. Ø Replace all EFI Preamp Caps in proper orientation Ø Verify No Other Caps Reversed Probes 1 - 5 at Rest in SAF SWT Overview 14 UCB, Nov 15/16, 2006

Probe & PC Status EFI Preamp Repair Plan ü ü ü q q q q SWT UCB-NASA Meeting to Gain Concurrence Build/Qualify New Stands Remove Solar Arrays Remove SPBs Remove AXBs Remove Preamps Replace Caps with proper orientation. Probe 1 on Rollover Fixture for Preamp Electrical ESA Conformal Coat Reassemble SPB and AXB Electrical Functional SPB and AXB Vibration Tests EFI Functional using FM 6 IDPU Install AXBs Install SPBs EFI Functional (Probe Level) Install Solar Arrays Probe Functional Probes 1 - 5 at Rest in SAF Overview 15 UCB, Nov 15/16, 2006

Probe & PC Status EFI Preamp Repair – Removal of SPBs and AXBs Probe 1 on Rollover Fixture for ESA Probes 1 - 5 at Rest in SAF SWT Overview 16 UCB, Nov 15/16, 2006

Milestones Ahead SWT Overview 17 UCB, Nov 15/16, 2006

Reviews Ahead SWT Overview 18 UCB, Nov 15/16, 2006