1. SPACECRAFT OVERVIEW/STATUS
Peter R Harvey
THEMIS Project Manager

2. Flight Systems Overview Ground Systems Overview
Agenda
Mission Objectives
Flight Systems Overview
Ground Systems Overview
Ground Based Observatories Overview
Major Reviews and RFAs
Current Status / Open Work
Issues
Summary

3. Mission Objectives
Probe conjunctions along Sun-Earth line recur once per 4 days over North America.
Ground based observatories completely cover North American sector; can determine auroral breakup within 1-5s …
… while THEMIS’s space-based probes determine onset of Current Disruption and Reconnection each within <10s.
: Ground Based Observatory

4. Mission Overview Launch Space Segment Ground Segment Operations
Vehicle: Delta II, Eastern Range
Apogee: km ± 9567 km
Perigee: 435 km ± 10 km (500 km ± 7 km on or after 3/1/2007)
Inclination: 16.0 deg ± 0.5 deg
Date: February 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: 20 Northern with All Sky Imagers and Magnetometers
Control Facilities: Mission and Science Operations Centers
Operations
Phases: L&EO, Cruise, Ascent, Campaigns, De-orbit
Lifetime: 2.3 years

5. Instrument Overview IDPU: Instrument Data Processor Unit
SPB : Spin Plane Booms (4x)
AXB : Axial Booms (2x)
SST : Solid State Telescope (2x)
ESA : Electrostatic Analyzer
FGM : Fluxgate Magnetometer
SCM : Search Coil Magnetometer

6. Probe Overview Antenna EFI Axial Booms (2, Stowed) ESA
Miniature Sun Sensor
Fuel Tank
IDPU
EFI SPB
Repress Tank
Fuel Tank
Transponder
Thruster A2
Thruster T1
EFI SPB
Thruster A1
BAU
Battery
Gyros
EFI SPB
Thruster T2
AEB

7. Launch Configuration
Dedicated launch accommodated within standard Delta 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 3rd 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 3rd Stage
Probe Carrier Assembly (PCA) on Delta 3rd Stage
THEMIS Launch Configuration

8. Ground System Overview
Ground System Elements
Ground Stations
Ground Network
Space Network
Mission Operations Center
Science Operations Center
Flight Dynamics Center
Including
Mission Design
Orbit & Attitude Determination
Maneuver Planning
Limit Detection and Notification
Network Security

9. Mission Operations Center
BGS Antenna, Equipment Racks and FOT Workstations at the Mission Operations Center

10. Secondary TLM/CMD/TRK
Ground Stations
Mission Supported by 5 Ground Stations
Ground Stations: BGS, WGS, MILA, AGO, HBK
GN, SN and FDF Support Documented in PSLA
All Stations Have Successfully Flowed Data with MOC
Ground Station
Station Designator
Figure of Merit
Location
Function
Berkeley, CA
BGS 11-m
24.0 dB/K
37.879° N
° W
Primary TLM/CMD/TRK
Wallops Island, VA
WGS 11-m
23.0 dB/K
37.925° N
75.476° W
Secondary TLM/CMD/TRK
Merritt Island, FL
MILA 9-m 1/2
21.6 dB/K
28.508° N
80.693° W
Santiago, Chile
AGO 9-m
33.151° S
70.668° W
Hartebeesthoek, SA
HBK 10-m
20.4 dB/K
25.883° S
27.708° E

11. Mission Profile 81

12. Ground Based Observatories
UCB has Delivered All 20 GBO (GMAG and ASI) units
19 Have Been Installed, 1 Needs Repair
Automatic Data Collection and Archiving in Progress
Remote Commanding and Diagnostics Working
Expect to be Fully Functional at Winter 2008
Courtesy H.Frey, UCB
Geographic
Longitude 324°
Longitude
195°
Geomagnetic
North Pole

13. Major Reviews

14. Final Two Closed since MRR
RFA Status
IIRT Reviews
IIRT Performed 27 Formal Reviews of THEMIS
IIRT Issued 308 RFAs and Recommendations
Project Completed & IIRT Concurred on all 308
Final Two Closed since MRR
RCS Proof
Launch Window Analysis
SMSR RFAs
Provide update on NROL-21 FOD Issue
Assess Issues with L3 Across Agency
MRB RFAs
Complete Launch Window Analysis
Update/Provide First Contact Timeline

15. Current Status/Open Work

16. Solar Array Illumination
Probe Processing
Delivery to ASO
Bolt Cutter Installation
Performance Tests
Solar Array Illumination

17. Probe Fueling Vibration Acoustics Spin Balance Dry Weigh & Pressurize
Thermal Vacuum
Storage

18. PCA Processing Final checks Acoustics Spin Balance PCA Integration
SSS Installation
Ready for Probes
Vibration
Fairing Installation
Spin Balance
Storage

19. Issues Bolt Cutter Thermal Tape
PCA Separation System Bolt Cutters Only Partially Taped
Concern Bolt Cutter Temp Would Exceed 160F Allowable
Access to Cutters Posed Some Risk to Payload
ULA Reran Thermal Analysis for Feb 15 to Mar
Predict Max Cutter Temperature of 100F
Concluded “as installed” is acceptable for flight.
Payload Concurred

20. Summary Issues Bolt Cutter Taping – Use as Is
P1115 Connector Demated – Closed
PCA-3rd Stage CG Offset – Closed
Summary Status
Probes and Probe Carrier are Flight Ready
Mission Operations is Complete
Launch Team and Operations Teams are Ready
Readiness Statement
THEMIS is Ready to Continue Processing for Launch