1 / 26

THEMIS Science Progress NASA/GSFC, Oct 26, 2007

THEMIS Science Progress NASA/GSFC, Oct 26, 2007. March 23, 2007 Event “THEMIS captures the Expansion of a Substorm in space” Lead: Angelopoulos. 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.

tamah
Télécharger la présentation

THEMIS Science Progress NASA/GSFC, Oct 26, 2007

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. THEMIS Science ProgressNASA/GSFC, Oct 26, 2007

  2. March 23, 2007 Event“THEMIS captures the Expansion of a Substorm in space”Lead: Angelopoulos

  3. 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

  4. TH-FGL Overview ____ ____ ____ X: Y: Z: THA-FGM FIT Data (3s) Available Note: Z=SMZ Rxy rotated X= - Ewd POLAR UVI/VIS Onset 10:58UT Intensifications

  5. From UVI At 11:18:26UT. Substorm intensifies @ 23MLT By 11:19:40UT. Auroras expand to 21.5MLT By 11:23:21UT Expansion slows down

  6. 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

  7. Hfrey_mar23_GBO_movie.mpg smoke New Auroral Intensification (Main, ~11:18UT) Previous Intensification (~11:10UT)

  8. Summary, March 23 11:18 onset • First direct detection of Westward Traveling Surge motion in the magnetosphere • 200km/s westward motion consistent with expectation from ground data • Expansion is motion of activity westward, flows are Earthward and duskward • Simultaneous inward and outward expansion of the injection • Azimuthal effects are dominant in this case THEMIS tail alignments in 2008 will be able to resolve temporal relationship and relative motion of current disruption, dipolarization and particle injections, one of the primary THEMIS objectives

  9. May 20, 2007 Event“THEMIS satellites dissect and reconstruct magnetic flux ropes at the magnetopause: ”Lead: Sibeck

  10. E C D THA THB

  11. ESA Electrons RDFs

  12. ESA gmoms Ni_all Ti_all

  13. B Y_gse C D E dBxy A V_sh X_gse • First – ever detection of a detached FTE at the magnetopause • Modeling and reconstruction of flows, fields suggests FTE is isolated from magnetopause • THEMIS, with its string-of-pearls orbit offers a unique opportunity to differentiate between boundary layer waves and detached plasma structures such as this FTE

  14. July 4, 2007 Event“THEMIS satellites detect extreme changes to the Earth-Sun boundary caused by interplanetary currents”Lead: Eastwood

  15. HFA Geometry Hot Flow Anomaly (HFA) detection A: Blue B: Cyan C: Green D: Orange E: Red A – in solar wind B, C, D, E – in magnetosheath The discontinuity underlying the HFA had just reached the bow shock The HFA had just started

  16. What are Hot Flow Anomalies? • Questions: • Plasma physics • Ion heating – current sheet particle scattering or beam instabilities)? • Ions: multiple populations or single population? • Electrons – isotropic and ‘Maxwellian’ [Schwartz et al., 2000] – how are the electrons heated? • Magnetospheric physics – what is their impact on the magnetosphere?

  17. Flow deflection, cavity forming, complicated series of magnetic field discontinuities First observation of HFA on both sides of the bow shock

  18. Simulations [Omidi and Sibeck, JGR 2007] 2.5D Global Hybrid simulation, courtesy Nick Omidi

  19. Simulations [Omidi and Sibeck, JGR 2007] 2.5D Global Hybrid simulation, courtesy Nick Omidi

  20. Propagation of pressure pulse down flanks • As the pressure pulse associated with the HFA propagates down the tail its signature moves from east to west (top to bottom) across the THEMIS magnetometer chain Petersburg Alaska

  21. First detection of the evolution of an HFA through the magnetopause and magnetosphere. • THEMIS is able to measure the evolution of particles and fields • Unremarkable solar wind features can have large implications for energy input to magnetosphere

  22. Publications: SSR Editors: J. Burch and C. T. Russell

  23. Publications: GRL, Special Issue Editors: M. Chen and N. Ostgaard

  24. Publications: JGR, Special Issue Editors: A. Battachargee, W. Baumjohann, Z. Pu

  25. Science Events: Outlook • AGU meeting (Dec 10-14) • 40 presentations to special session on multi-spacecraft observations (Mon-Tue) • Pre-AGU community engagement event under auspices of GEM • THEMIS data and software tools: tutorial for the community • SWT meeting (Dec 15, UCB) • SWT meeting (Apr 6-9, Southern CA) • First joint analysis of substorm events • Intl. Substorm Conference (ICS9) meeting (May 4-8, Graz) • First presentations of substorm events from THEMIS • Special issue at Annales Geophysicae • Joint THEMIS-Cluster Workshop, (October 2008, UNH) • Results from first year of THEMIS nominal science operations

More Related