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Introduction, THEMIS overview First THEMIS results from the tail THEMIS results in other regions

THEMIS First Results and near future. Introduction, THEMIS overview First THEMIS results from the tail THEMIS results in other regions Data availability Future activities. : Ground Based Observatory. THEMIS Mission elements.

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Introduction, THEMIS overview First THEMIS results from the tail THEMIS results in other regions

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  1. THEMIS First Results and near future • Introduction, THEMIS overview • First THEMIS results from the tail • THEMIS results in other regions • Data availability • Future activities

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

  3. Near-Earth tail reconnectionLocalization: the case for “point” reconnection Angelopoulos et al., 1998 (Case study on localization) Nakamura et al., 2004 (Cluster statistics on localization) Scales: Vertical: 1.5-2 RE, Azimuthal: 2-3 RESharper gradient on duskside flank

  4. Nagai 1991 results T = -0.01 x MLT**4 - 0.06 x MLT**3 + 1.16 x MLT**2 + 1.13 x MLT + 0.27 T delay time (minutes) at each MLT Here, 23 MLT is -1.0, 22 MLT is -2.0 24 MLT 0.27 min (not well bound by data, a statistical average) 23:32MLT 0.00 min (the center of the current wedge, average) 23 MLT 0.35 min (not well bound by data, a statistical average) 22 MLT 2.97 min 21 MLT 8.13 min 20 MLT 15.59 min

  5. The 3D nature of the Rx process 0204UT JGR [Angelopoulos et al, 1995] Substorm Onset: ~0202UT Ygsm Xgsm 0215UT Ygsm

  6. EFIs EFIa SCM ESA BGS SST Operations UCB FGM Tspin=3s Instrument I&T UCB Ground Mission overview D2925-10 @ CCAS Release Probe instruments: ESA: ElectroStatic Analyzer(coIs: Carlson and McFadden)SST: Solid State Telescopes (coI: Larson)FGM: FluxGate Magnetometer(coIs: Glassmeier, Auster & Baumjohann)SCM: SearchCoil Magnetometer (coI: Roux) EFI: Electric Field Instrument (coI: Bonnell) Encapsulation & launch Mission I&T UCB

  7. First light: Nature’s welcome. Two substorms seen on March 23 http://sscweb.gsfc.nasa.gov/tipsod DETAILED VIEW THEMIS TH-E THE Y Y TH-A Z TH-B TH-D X TH-C SUN THA THB X THC THD Z SUN POLAR

  8. From UVI Courtesy: Parks and Fillingim At 11:18:26UT. Substorm intensification @ 23MLT By 11:19:40UT. Auroras expand to 21.5MLT By 11:23:21UT Not much further expansion Consistent with VIS due to 0.5MLTUVI uncertainty from POLAR wobble

  9. From VIS: 2007_082_1008-1309_all.mov At 11:18:03-45UT. Auroras brighten @ 23MLT By 11:19:57UT. Auroras expand to 22MLT By 11:23:21UT No further westward expansion observed

  10. Keograms from UVI

  11. At 11:18:42UT. From: 3_23_07_mosaic.mov Onset at 11:18:42UT@ 23MLT (see Mende et al.)

  12. Apatenkov/Sergeev model:SCW Upward FACjumps to 21.5MLT andstays there for >20 minutes

  13. Classical mapping Tsyganenko 2001mapping: THEMIS maps to21.5 MLT (other models, orhigher activity place thm tothe West). 21.5MLT

  14. Simulation mapping OpenGGCM mapping:THEMIS just before simulation onset maps to ~22.5 MLT, i.e.,right in the middle of expandingactivation. Note: mapping evolves Courtesy: J. Raeder (UNH)

  15. Z Y X B FAC By sc B Assuming an outward plasma sheet expansion (evidenced by the |Bx| reduction - interpreted as a diamagnetic effect) the FAC is a pair of oppositely directed current sheets, embeded in an overall outward currentsheet. This is consistent with THEMIS being at the westward edge of the WTS.

  16. Moments Overview TH-D

  17. Vorticity in FAC coordinates From TH-D,B,A (inner) Check using different center probe From DBA, BAD, ABD Courtesy: L. Kepko (UNH)

  18. Strangeway et al. SM11Aobserve similar signatures of FAST

  19. Conclusions, March 23 event: • Measured expansion is much faster than previously measured locally but agrees with expectations from statistical averages First time it has been observed by nearby satellites. • Expansion speed on the ground ~ 1 MLT hrs/minMaps to 10RE as 200km/s westward (250km/s along track) • Observed speed in space (from time delays) is ~250km/sFrom 10RE it maps on the ground to ~1 MLT hrs/min • Orientation of expansion needs further investigation (under way)Use remote sensing and finite gyroradius techniques • Note: is was no continuous expansion of the WTS.A new activation appeared Westward of an old one.Likely the norm?

  20. Examples of THEMIS capabilities Mende et al, GRL 2007

  21. Coast, Placement and Tail Phases Coast phase dayside (May-Aug ’07) http://sscweb.gsfc.nasa.gov/tipsod/ Placement (Sep-Dec ’07) Tail 1 (Jan ’08 – Mar ’08) http://sscweb.gsfc.nasa.gov/tipsod/

  22. FTEs on TH-D: Detail

  23. Dissection of an FTE by THEMIS Sphere Dusk MP -,+ Sheath Sibeck et al., SM 22B-08

  24. Magnetopause reconnection event(May 21) TH-B TH-B TH-C TH-C TH-D TH-D TH-E TH-A TH-E TH-A Phan et al., SM 22B-01

  25. Magnetopause reconnection event,May 21 example - detail

  26. Remote sensing of FTEs: dayside TCRs Liu Jiang, SM11A-0316 B D C E A

  27. Upcoming Tail Season Activities Scheduled Cluster-THEMIS coordination intervals Scheduled AMISR, Sondestrom radar scans SuperDARN in THEMIS mode, w/ added midlat radars Cluster-THEMIS, side view Cluster-THEMIS, top view

  28. Data availability

  29. THEMIS Data Policy • Open data policy • Data on the street only 2 weeks after collection • Also, preliminary calibrations and overview plots • Also, software for analysis available • Credits. Always credit: NAS5-02099 • Strongly recommend to consult PI/coIs on data before study • Editors will be requested to ensure above have been implemented. • First publications by instrument leads • Space Science Reviews papers • First data papers within • One compendium, demonstrates instrument and use of data • GRL special issue on first science results • Community • Tag team with individual instrument leads to learn use of data • Engage in scientific discussions with coIs • Acknowledgement sufficient, if for use of data alone • Co-author instrument providers if helpful in data interpretation

  30. Anticipating an Exciting Tail Season Expect first substorm results to be reported in ICS-9

  31. The fun has just begun! Do not miss out! Join the THEMIS society!

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