Constellation Status, Plans for Future Manfred Bester University of California - Berkeley

1. Constellation Status, Plans for Future Manfred Bester University of California - Berkeley

2. Overview • Overview • Prime Mission • Constellation Status • Science Operations • Maneuver Summary • Fuel Budget • Extended Mission • ARTEMIS Concept of Operations • Top Level Schedule • Network Communications • Roles and Responsibilities • Navigation Plans • Summary of Future Plans

3. Prime Mission Time History of Events and Macroscale Interactions during Substorms (THEMIS) NASA Medium-class explorer mission Managed in PI Mode by UCLA/UCB http://themis.ssl.berkeley.edu http://www.nasa.gov/themis 5 Probes in synchronized Earth orbits with periods of 4, 2 and 1 days Conjunctions are formed in magnetospheric tail every 4 days

4. Successful Launch Campaign Launch: February 17, 2007 Probe Release: L + 70 min Responsibility for Constellation Operations Transitioned to MOC at UCB

5. Prime Mission Status Summary • Prime Mission Status • Completed LEOP, coast phase, tail 1 and dayside 1 • Upcoming tail 2 and dayside 2 seasons • Answered primary scientific questions already • Constellation Status • All probes very healthy and collecting science data • Fuel reserves allow for ambitious mission extension • Ground Systems & Operations Status • All ground systems processing nominally • Executed 248 individual thrust operations to date • Completed 10,000 passes on December 3, 2008 • All routine passes supported in lights-out mode

6. Constellation Status Page

7. Science Operations • Science Instrument Commanding • Configuration changes discussed in ops meetings • All instruments command sequences typically tested on FlatSat prior to upload • Ops team implemented 75 ICCRs to date • Science Data Recovery Metrics • Data dumps near perigee at 512K or 1024K • Outer probes get two passes whenever possible • Recovered / acquired data volume: 98 - 99% • Recovered / required data volume: 111 - 147% • Tohban monitors data quality and completeness

8. Flight Systems Status

9. Anomaly Tracking • Anomaly Tracking & Resolution • Tiger Team assigned for each flight system or major ground system anomaly • Investigate and determine cause of anomaly • Recommend solutions, work-arounds and/or mitigations • Provide final report • Anomaly Tracking List • Items closed out when anomaly report released and recommended actions were performed • Currently tracking 29 items (20 closed)

10. THEMIS Orbit Determination • Orbit determination (OD) for the THEMIS constellation is based on two-way Doppler tracking data and the Goddard Trajectory Determination System (GTDS). • Tests are underway to characterize the THEMIS ranging capabilities for use during ARTEMIS.

11. Executed Maneuver Summary * ARTEMIS Probes Total executed thrust operations: 248

12. P1 Large Plane Change Maneuver ΔV: 296.5 m/s Fuel: 13.2 kg

13. P2 Large Plane Change Maneuver ΔV: 227.7 m/s Fuel: 10.5 kg

14. P1 Planned Maneuvers • * Spin target is 20.2105 ± 0.0130 rpm

15. P2 Planned Maneuvers • * Spin target is 20.2105 ± 0.0130 rpm

16. P1 & P2 Remaining Fuel

17. Extended Mission Time History of Events and Macroscale Interactions during Substorms (THEMIS) 3 Probes (A/P5, D/P3, E/P4) in synchronized Earth orbits with 1-day periods Acceleration, Reconnection, Turbulence and Electrodynamics of the Moon’s Interaction with the Sun (ARTEMIS) 2 Probes (B/P1, C/P2) in lunar orbits

18. ARTEMIS ConOps • ARTEMIS Concept of Operations • Transfer of outer two probes (B/P1 and C/P2) into lunar orbits via Weak Stability Boundary trajectory using Earth and lunar gravity assist • Communications with these two probes via DSN • Data recovery from lunar distances up to 128K • Attitude determination with sun sensor data only • No required flight software changes • THEMIS Concept of Operations • THEMIS mission continues with inner three probes (A/P5, D/P3, E/P4) in tighter formation NOTES: For all operational purposes all five probes shall continue to be referred to as THEMIS A-E. New capabilities at the MOC shall be considered an upgrade, not a transition.

19. Network Communications THEMIS Probes TDRS GDSCC DSS-24, 27 CDSCC DSS-34, 45 MDSCC DSS-54, 65 WS1, AGO, MILA, WGS JPL DSN BGS Secure Intranet White Sands Complex USNHI, USNAU USN NMC GSFC NMC Open IONet T1 Line Isolated Dial-up ISDN Line THEMIS/ARTEMIS Network Links Berkeley Multi-mission Operations Center HBK

20. Spacecraft Constraints

21. Thruster Firing Modes

22. Roles and Responsibilities • ARTEMIS Navigation Team • Mission Design & Baseline Trajectories • JPL/GNC • Trajectory Verification & Validation • GSFC/FDAB • Navigation Plans & Error Analysis • GSFC/FDAB • Maneuver Targeting & Operations • GSFC/FDAB & UCB/SSL • Orbit Determination & Error Analysis • GSFC/FDF & UCB/SSL • Attitude Determination • UBC/SSL with software provided by GSFC/FDAB and a.i. solutions

23. Top Level Schedule

24. P1 Impulsive ORM Sequence THEMIS D2 ORM 1 ORM 8

25. P1 Lunar Approaches

26. Navigation Work Flow Finite Trajectory Design JPL/NAV Orbit Determination Predictive Ephemeris GSFC/FDF Maneuver Operations UCB Ephemeris Products Telemetry Data Initial Trajectory Maneuver Planning GSFC/FDAB Maneuver Reconstruction UCB Trajectory Verification and Correction GSFC/FDAB GMAN/GMAT Config Post Execution State Validated Trajectory Maneuver Verification UCB Orbit Determination Definitive Ephemeris GSFC/FDF Ephemeris Products Thruster CMD Sheets Acquisition Data Planning Products Maneuver Calibration GSFC/FDAB & UCB

27. Summary • Near Term Plans • Complete second tail season by April 2009 • Outer probes maneuvered close to neutral sheet • Finalize ARTEMIS mission design • Mid Term Plans • Complete second dayside season by July 2009 • Start orbit raise maneuver sequence for P1 & P2 • Long Term Plans • Execute translunar trajectory phase for ARTEMIS (P1 & P2) • Operate THEMIS (P3, P4, P5) in closer formation

28. Going Back to the Moon Launch: July 16, 1969 Landing: July 20, 1969 40 Years Later …