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THEMIS Status (since Receiving Review 2007.06.28) NASA/GSFC, Oct 26, 2007. Mission Profile Overview. Q1 period. Dayside (Coast Phase): Checkout and Serendipetous science. Starting point: launch configuration. TH-B. TH-C. TH-B. TH-D. TH-C. TH-D. TH-E. TH-A. TH-E. TH-A.
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THEMIS Status(since Receiving Review 2007.06.28) NASA/GSFC, Oct 26, 2007
Mission Profile Overview Q1 period
Dayside (Coast Phase): Checkout and Serendipetous science Starting point: launch configuration TH-B TH-C TH-B TH-D TH-C TH-D TH-E TH-A TH-E TH-A
Dayside: Spacecraft • Constellation status • Orbits and Attitudes • 31.3hr Orbit Periods (RA=14.6RE) • Spin axis ecliptic science North (+8deg towards Sun on Feb 7, 2008) • Configuration: • B-------------------C-D-E--------------------A---- 5,000km 200km 5,000km • Spacecraft Status: All spacecraft healthy, performing nominally
Dayside: Instruments • Instrument status • All Powered ON and Nominal • Instrument behavior: • FGM 11Hz noise persists, identified as ETC 32sector sampling • Difficult but not impossible to clean • SCM and FGM spin tone harmonics • Software cleanup on SCM (1m) done, on FGM (2m boom) awaiting testing
Dayside: Instruments • Data acquisition modes • On-board moments corrected: late August 2007
Dayside: Instruments Instrument operations routine modes
Dayside: Summary of Activities • Sequence of Events: • At: http://soleil.ssl.berkeley.edu/ground_systems/request_planning.themis.txt • Pass Coverage and Data Recovery: • Minor data losses only due to: • Beating of 31.3hr orbit with 24h rotation, and memory overfill • Lining up USN to improve outlook, and as backup • Pass statistics
On board memory fill state records: • BTAPS, or available through hsk in THEMIS Data Analysis Tools Burst Memory full Collect Memory dump Survey Full
Dayside: Summary of Activities • Normal Operations: • Pass supports, state-of-health monitoring, generation and uploading of tables, clock correlation, instrument ops. Lights-out support conducted. • Clock correlation and jamming (to adhere to 0.5s across) is typical. • Average clock drift rates: • TH-A TH-B TH-C TH-D TH-E • 8.9msec/d 4.5msec/d 4.0 msec/d 0.47msec/d 2.5msec/d • Thruster Utilization at end of dayside:
Dayside: Anomaly Status • Mission totals to end-of-dayside: • 15 anomalies, • 11 closed by RR • 4 closed recently Closed Closed Closed Closed
Dayside: Ground System • Mission Ops Center: • All tools function nominally (ITOS, SatTrack, BMPS, BTAPS, BEARS) • All systems under soft configuration freeze • SW/HW changes are reviewed, documented and approved by local CCB • Flight Dynamics • All tools function nominally (MDT, GMAN, GTDS) • Regular mission-life runs ensure conjunctions, fuel margins and shadows are maintained • OD performed 3times/wk ; AD performed 1time/wk • Automated generation of mission planning products (GSFC/FDAB backup) • Berkeley Ground Station • BGS functions nominally • Recent procurement of Microdyne RCB-3000 receiver improved link margin • Exciter (Agilent ESG 4422B) which had failed was refurbished • 200W Transmitter had an issue but was shipped to factory and fixed (100W OK) • External Ground Systems • NASA G/N; NASA S/N; GSFC/FDF; NISN continue their support to THEMIS • Wallops Ground Station has had problems (AGC level zeroing) but are worked on • Hartebeesthoek Ground Station (12m, 6m) experienced problems but being fixed • USN (Australia, Hawaii) are being lined up for THEMIS.
Dayside: Data Processing • Science Data Processing • L0, L1 and L2 data automatically generated within <1hr from receipt. • Tohban-process checks data fidelity to catch issues almost real-time. • DVD production system recently installed for backup media • Data plots on the web with 2hr latency • Data gaps backfilled by reprocessing of packets subsequent passes (1-2days later) • Automated reprocessing upon arrival of any new data • Processing Software Status • Quality Assurance checks on “released version” completed: July 31 (V2.0) • Production of L1, L2 data and overview plots • Available for distribution to the world (http://themis.ssl.berkeley.edu/software) • Support through on-line form or email (THEMIS_Science_Support@ssl)
Data Processing (…cont.) L0: packets (THEMIS web / TDAS) L1: raw uncalibrated, CDFs (THEMIS web / TDAS) L2: physical, calibrated, CDFs (… plus SPDF) … soon also through VxOs p. 1
Data Processing (…cont.) • L1 Data: • Now contain: • Everything • L2 Data: • Now contain: • Full resolution B-field • Spin resolution E-field • Omni-spectra ESA, SST • Filterbank waves • SS gmoms @ 5min • By Dec. 07 will contain: • FS gmoms @ 3sec resolution • SS moms @ 3sec resolution • By Feb. 07 will contain: • Full resolution SCM data • (& possibly full res. Exy, Edot0) p. 2
Dayside: Data Validation • Tohban (scientist-in-charge) performs routing data quality checks • See: http://sprg.ssl.berkeley.edu/~themistohban/ • Data gaps, FS, PB captures, mode switches – informs of problems • Filters instrument requests to instrument engineer (Ludlam),so that scientists speak with ONE voice • Reports weekly status during Mission Operations Meetings; plots interesting data
Data Delivery • Data and software delivery of L0, L1, L2 data through UCB • See: http://sprg.ssl.berkeley.edu/data/ • Machine independent, IDL-based software downloads seamlessly the THEMIS data in CDF (machine independent Format) • Latency = 2hrs from data receipt on the ground • Data and software delivery of L2 data through SPDF • See: http://spdf.gsfc.nasa.gov/ • Documented physical quantities in CDF, readable by any software (IDL, Matlab, C++) • Data and software delivery of L2 data through VxOs • Working directly with Jan Merka (spacecraft) and Ray Walker/Todd King (gmags) • Defining SPASE+ model for THEMIS and describe dataset • Developing SOAP interface for Remote procedure calls (RPCs) from VMO • Designing/creating basic search procs for VMO middleware to return pointers • Defining advanced search procedures for higher resolution, or transformed data
Dayside: Event detection • Web-based overview plot distribution (http://themis.ssl.berkeley.edu/data): • Single spacecraft 24 hr, 6 hr overviews • Multi-spacecraft overviews (FGM now available, ESA soon) • Orbit views • GBO GMAG stackplots (High- & Mid-Lat for H, D, Z)
Coast, Placement and Tail Phases http://sscweb.gsfc.nasa.gov/tipsod/ Coast (Jun –Sep, 2007) Placement Sep-Dec, 2007) Tail 1 (Jan-Mar, 2008)
Placement: Status Overview • Proceeding Nominally • Most maneuvers completed • P1 (TH-B), P2 (TH-C), P3 (TH-D), P4 (TH-E), near final orbits • P1, P2 turned to near-final attitudes (ecliptic science south) • Short-term science took secondary priority during this placement period • ESAs were turned OFF for a few weeks to simplify operations (most back ON now) • Data retrieval was curtailed due to: • Non-optimal attitudes (probes left to fire attitude thru several orbits) • Maneuver contacts at perigee took precedence over data dumps • Software uploads (compression, triggers, FS) lagged behind (now starting again) • FSW 4.8 upload on TH-A, B done, next is C, D, E (fixes compression, Ni triggers) • Mission Ops personnel focused on safe placement • Maneuver planning/replanning in response to inadvertent aborts • Long term (end-to-end) mission design stability to achieve mission goals • Achieved most placement events while maintaining mission objectives: • Accurate orbit placement for tail season • First and second year conjunctions > 250hrs/yr (Baseline=188hrs/yr) • First and second year shadows <3hrs (meets design limits) • End-of-mission dV expected on P1 = 300m/s (80% over the remaining dV) • Issues (minor, non-critical): • Tank local temperature swings due to lower heat capacity; cycling faster now. Watch. • Thanks to the efforts of the dedicated individuals of the Msn Ops Team !! • Special Thanks to MOM, Manfred Bester, for his Leadership and Focus.
Placement: Science Data Dumps Spotty – Priority on Maneuvers • Still… Collected most survey data. Interesting on-board FGM/FIT data collected during this period Burst Memory full Survey Full
Placement: Outlook • Spacecraft • P3,4 into sidereal periods by Oct 30th & Nov 3rd • P5 (TH-A) starts placement maneuvers once P1’s EFI booms are out (Nov 17) • Instruments • All ESAs to be turned ON by next week • P1 EFI boom deployment plans developed (EFI expected out by Nov 17) • P5 EFI booms to come out shortly after its placement (early January) • Data Collection • Missing magnetopause crossings on P3,4 (too close@12RE) – Revising FS plan: • Start Tail-Like science operations early (WD-88d I.e., Nov 3) • FS during conjunctions • One-day GBO conjunctions for P3,4,5 (0-12 UT) • Two-day conjunctions for P2 • Four-day conjunctions for P1 • Particle Burst using Vxy, Bz • Wave Burst using FBK triggers • Benefits: • Practice tail-alignment operations early • Dawn-side science captures dawn flank at multiple distances • Can plan radar conjunctions (AMISR, SuperDARN) from now • Investigating early EFI deployment on P5