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Mission Science Vassilis Angelopoulos  Mission Science Overview and Investigation Strategy

Mission Science Vassilis Angelopoulos  Mission Science Overview and Investigation Strategy  Science Team Preparations and Readiness  Full and Minimum Science Criteria  EPO. T IME H ISTORY OF E VENTS AND M ACROSCALE I NTERACTIONS DURING S UBSTORMS (THEMIS). SCIENCE GOALS:

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Mission Science Vassilis Angelopoulos  Mission Science Overview and Investigation Strategy

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  1. Mission Science Vassilis Angelopoulos  Mission Science Overview and Investigation Strategy  Science Team Preparations and Readiness  Full and Minimum Science Criteria  EPO

  2. TIME HISTORY OF EVENTS AND MACROSCALE INTERACTIONS DURING SUBSTORMS (THEMIS) • SCIENCE GOALS: • Primary: • “How do substorms operate?” • One of the oldest and most important questions in Geophysics • A turning point in our understanding of the dynamic magnetosphere • First bonus science: • “What accelerates storm-time ‘killer’ electrons?” • A significant contribution to space weather science • Second bonus science: • “What controls efficiency of solar wind – magnetosphere coupling?” • Provides global context of Solar Wind – Magnetosphere interaction RESOLVING THE PHYSICS OF ONSET AND EVOLUTION OF SUBSTORMS Principal Investigator Vassilis Angelopoulos, UCB EPO Lead Nahide Craig, UCB Project Manager Peter Harvey, UCB Industrial Partner SWALES Aerospace

  3. Auroral eruptions and substorms …are a manifestation ofmagnetospheric substorms Auroral eruptions… SOLARWIND Aurora MAGNETOSPHERE EQUATORIAL PLANE

  4. : Ground Based Observatory 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; can determine auroral breakup within 1-5s …

  5. First bonus: What producesstorm-time “killer” MeV electrons? Affect satellites and humans in space ANIK telecommunicationsatellites lost for days to weeksduring space storm • Source: • Radially inward diffusion? • Wave acceleration at radiation belt? • THEMIS: • Tracks radial motion of electrons • Measures source and diffusion • Frequent crossings • Measures E, B waves locally

  6. Second bonus: What controls efficiencyof solar wind – magnetosphere coupling? • Important for solar wind energy transfer in Geospace • Need to determine how: • Localized pristine solar wind features… • …interact with magnetosphere • THEMIS: • Alignments track evolution of solar wind • Inner probes determine entry type/size

  7. THEMIS is firmly aligned withNASA’s Vision for Space Exploration • …To Explore Earth-Sun System and understand effects on Earth and implications for human exploration [Strategic Roadmap #10 of Exploration Initiative] • Radiation hazards pose a risk to spacecraft and humans in Earth orbit and en-route to Mars • Radiation is caused by solar energetic particles and galactic cosmic rays, and radiation belts • Nowhere else can the understanding of the underlying physics of particle acceleration more comprehensive, detailed and complete than at and around Earth’s vicinity. • Exploration building blocks: • Understand processes of particle acceleration at Earth and in solar wind • Understand interactions between solar wind and planetary magnetospheres • Understand how harmful particle populations develop and evolve • Predict conditions and implications of radiation for human exploration • THEMIS is a critical element of the ESS Exploration agenda: • Addresses how fundamental particle acceleration processes operate • First comprehensive, coordinated measurements of energy sources and sinks • Tracks energetic particles from seed to target • Probe conjunctions strategically designed to answer this question

  8. Science Objectives • THEMIS HAS FOCUSED MINIMUM (TO BASELINE) OBJECTIVES: • Time History of Events… • Auroral breakup (on the ground) • Current Disruption [CD] (2 probes at ~10RE) • Reconnection [Rx] (2 probes at ~20-30RE) • … and Macroscale Interactions during >5 (>10) Substorms (Primary): • Current Disruption and Reconnection coupling • Outward motion (1600km/s) of rarefaction wave • Inward motion of flows (1000km/s) and Poynting flux. • Ionospheric coupling • Cross-tail current reduction (P5u/P4) vs flows • Field aligned current generation by flow vorticity, pressure gradients (dP/dz, dP/dx). • Cross-scale coupling to local modes • Field line resonances (10RE, 5 min) • Ballooning modes, KH waves (1RE, 1min) • Weibel instability, cross-field current instability, kinetic Alfven waves (0.1RE, 60Hz) • Production of storm time MeV electrons (Secondary) • Control of solar wind-magnetosphere coupling by the bow-shock, magnetosheath and magnetopause (Tertiary)

  9. Probe conjunction requirements • BASELINE: >10 substorms per year for 2 tail seasons (188hrs / tail season) • MINIMUM: >5 substorms in 1yr w/ 4 probes in 1 tail season (94hrs total). • dYP1/2/3/4/5<±2RE; dZP3,4,5/NS<±2RE; dZP1,2/NS<±5RE Actual conjunction times in 1st year • Prime Science: Feb 15+/- 1.5 mo: • Between Winter Solstice and Equinox • A compromise: Shadows vs Conjunctions • Launch Delay (Oct 19 ’06 to Feb 15 ‘07) effects: • Baseline science yield and quality are still nominal • Adds an 8mo. coast phase ahead of 1st tail season • Probes assigned positions early, placements after coast phase • Avoids differential precession • P2,3,4 deploy EFIs vs. P1,5 keep EFIs stowed for placements • Compromise: ease of placement vs. early science

  10. Probe conjunctions satisfied Launch day analysis:Feb 15 to May 15, 2007 Conjunctions are robust Nominal deltaV marginfor operations at launch: >25% for baseline mission >15% for replacement probe Conjunction Hours Expected: >25% margin above baseline >150% margin by 1st Tail Season Tail 2 Baseline Requirement Baseline Requirement Dayside Tail 1 Baseline Requirement Minimum Requirement

  11. EFIs EFIa SCM ESA SST FGM Tspin=3s Instruments required: Redundancy and Overlap 1 FGM: Low freq. B-field (0-64Hz) 1 ESA: Thermal plasma2 SSTh (heads): Super-thermal plasma1 SCM: High freq. B-field (1Hz-4kHz) 4 EFIs (spin plane) & 2 EFIa (axials): Low&High freq. E-field

  12. Baseline L1 Requirements • S-1 Substorm Onset Time • Determine substorm onset time and substorm meridian magnetic local time (MLT) using ground ASIs (one per MLT hr) and MAGs (two per MLT hr) with t_res<30s and dMLT<1 degree respectively, in an 8hr geographic local time sector including the US. (M-11, GB-1) • S-2 Current Disruption (CD) Onset Time • Determine CD onset time with t_res<30s, using two near-equatorial (within 2Re of magnetic equator) probes, near the anticipated current disruption site (~8-10 Re). CD onset is determined by remote sensing the expansion of the heated plasma via superthermal ion flux measurements at probes within +/-2Re of the measured substorm meridian and the anticipated altitude of the CD. (M-9, IN.SST-1, IN.SST-4, IN.FGM-1) • S-3 Reconnection (Rx) Onset Time • Determine Rx onset time with t_res<30s, using two near-equatorial (< 5Re from magnetic equator) probes, bracketing the anticipated Rx site (20-25Re). Rx onset is determined by measuring the time of arrival of superthermal ions and electrons from the Rx site, within dY=+/-2Re of the substorm meridian and within <10Re from the Rx altitude. ….. (M-9, IN.EFI-2, IN.ESA-1, IN.SST-2, IN.SST-3, IN.SST-4, IN.FGM-1) • S-4 Simultaneous Observations • Obtain simultaneous observations of: substorm onset and meridian (ground), CD onset and Rx onset for >10 substorms in the prime observation season (September-April). Given an average 3.75hr substorm recurrence in the target tail season, a 2Re width of the substorm meridian, a 1Re requirement on probe proximity to the substorm meridian (of width 2Re) and a 20Re width of the tail in which substorms can occur, this translates to a yield of 1 useful substorm event per 18.75hrs of probe alignments, i.e, a requirement of >188hrs of four-probe alignments within dY=+/-2Re. (M-1, M-12, IN.FGM-1)

  13. … continued: Baseline L1 Requirements • S-5 Earthward Flows • Track between probes the earthward ion flows from the Rx site and the tailward moving rarefaction wave in the magnetic field, and ion plasma pressure with sufficient precision to ascertain macroscale coupling between current disruption and reconnection site during >10 substorm onsets (>188hrs of four-probes aligned within dY of +-2Re). (IN.ESA-1, IN.SST-3, IN.FGM-1) • S-6 Pressure Gradients • Determine the radial and cross-current-sheet pressure gradients and ion flow vorticity/deceleration with probe measurement accuracy of 50km/s/Re, over typical inter-probe conjunctions in dR and dZ of 1Re, each during >10 onsets. (IN.EFI-1, IN.ESA-1, IN.ESA-2, IN.SST-3, IN.FGM-1) • S-7 Cross-Current Sheet changes • Determine the cross-current-sheet current change near the current disruption region (+/-2Re of meridian, +-2Re of measured current disruption region) at substorm onset from a pair of Z-separated probes using the planar current sheet approximation with relative (interprobe) resolution and inter-orbit (~12hrs) stability of 0.2nT. (IN.FGM-1, PB-42, PB-43, PB-44) • S-8 non-MHD plasma • Obtain measurements of the Magneto-Hydrodynamic (MHD) and non-MHD parts of the plasma flow through comparisons of ion flow from the ESA detector and ExB flow from the electric field instrument, at the probes near the current disruption region, with t_res<10s. (IN.EFI-1, IN.ESA-1, IN.SST-3, IN.FGM-1)

  14. … continued: Baseline L1 Requirements • S-9 Cross-Tail Pairs • Determine the presence, amplitude, and wavelength of field-line resonances, Kelvin-Helmholz waves and ballooning waves on cross-tail pairs (dY=0.5-10Re) with t_res<10s measurements of B, P and V for >10 substorm onsets. (IN.ESA-1, IN.SST-3) • S-10 Cross-Field Current Instabilities • Determine the presence of cross-field current instabilities (1-60Hz), whistlers and other high frequency modes (up to 600Hz) in 3D electric and magnetic field data on two individual probes near the current disruption region for >10 substorm events. (IN.EFI-3, IN.ESA-3, IN.SCM-1) • S-11 Dayside Science • Determine the source and acceleration mechanism of storm-time MeV electrons at the radiation belts by measuring the radial evolution of the electron phase space density over time-scales of 2-6 hrs. (IN.ESA-4, IN.SST-6) • S-12 Dayside Science • Determine the nature, extent and cause of magnetopause transient events via comparing simultaneous measurements of the dynamic pressure in the pristine solar wind and the foreshock with magnetic field perturbations near the magnetopause. (IN.ESA-4, IN.SST-6)

  15. Minimum L1 Requirements (from L1’s) • 4.1.2.1 Substorm Onset Time • Determine substorm onset time and substorm meridian magnetic local time (MLT) using ground MAGs (at least one per MLT hr) with t_res<30s and dMLT<6 degrees respectively, in a 6hr geographic local time sector including the US. • 4.1.2.2 Current Disruption (CD) Onset Time • Determine CD onset time with t_res<30s, using two near-equatorial (within 2Re of magnetic equator) probes, near the anticipated CD site (~8-10 Re). …(same as baseline) • 4.1.2.3 Reconnection (Rx) Onset Time • Determine Rx onset time with t_res<30s, using two near-equatorial (<5Re of magnetic equator) probes, bracketing the anticipated Rx site (20-25Re). … (same as baseline) • 4.1.2.4 Simultaneous Observations • Obtain simultaneous observations of: substorm onset and meridian (ground), CD onset and reconnection onset for >5 substorms in the prime observation season (September-April). Substorm statistics discussed in S-4 point to a requirement of >94hrs of four probe alignments. • 4.1.2.5 Earthward Flows • Track between probes the earthward ion flows from the reconnection site and the tailward moving rarefaction wave in the magnetic field, and ion plasma pressure with sufficient precision precision to ascertain macroscale coupling between current disruption and reconnection site during >5 substorm onsets.

  16. Science Team Composition • Added Strength w/ 5 new coIs: • J. Bonnell (EFI) • D. Larson (SST) • J. P. McFadden (ESA) • I. Mann (UoA GBO, RadBelt) • I. Daglis (Athens, Ring Current) • Established Partnerships with: • Taiwan [Affiliate F. Cheng] • Cluster [Affiliate S. Schwarz] • SPDF [Affiliate R. McGuire] • CCMC [Affiliate M. Hesse] • Enlisted young bright stars: • Chaston, Eastwood, Hull, Keiling (UCB), Strangeway, Schwarzl, Weygand (UCLA) • Team is ready, awaiting launch!

  17. Science Team Meetings and Products • Meetings • Yearly post-AGU meetings at UCB since 2003 • “Data analysis tools” meeting at UCB, Nov-15-2006 • Exposed team to (and obtain feedback on) • data analysis tools before they are finalized • coast phase intra-calibration and unique science • Weekly Science and Science Ops Center Development meetings • Weekly International Instruments telecons (FGM, SCM, ASIs) • Cape Canaveral Feb 13-15 meeting announced (Team+Community) • Call for Space Science Reviews instrument papers to be submitted • Expect comprehensive volume by next summer, out well before for Tail 1: • Analysis tools and methods • First instrument results • Web page development: • Contracted analysis tools and data dissemination web-site • Brainstorming team and Contractor interfaces established • Skeleton and content material in place in beta site • User interviews on-going to establish best look and feel.

  18. Science Data Products Status Level 0 Data : Raw files (*.pkt) one per APID (application identifier, straight from telemetry). Level 1 Data : Processed but uncalibrated data in CDF (Common Data Format) files (*.cdf) Software and calibration files will be distributed with the data. Level 2 Data: Calibrated data in CDF files – contain physical quantities.

  19. Science Team Data Analysis Tools Status (1) • Analysis tools available now (IDL-based) at:http://themis.ssl.berkeley.edu/beta • Platform independent, works on Solaris, Linux, Win, MacOSx • Auto file retrieval • Easy to install and download files • GUI available for IDL starters • Contributions by any scientist • Maintenance with SubVersioN • Documentation includes: • Users Guide • Developers Guide • Subversion • Latest list of routines

  20. Science Team Data Analysis Tools Status (2) • Anyone can plot L1 data from THEMIS today:http://themis.ssl.berkeley.edu • Data from I&T period, is auto-processed whenever software is updated • Working on mirror sites • Additional plots at SPDF: • via CDAWweb

  21. Science Team Data Analysis Tools Status (3) • Orbit Visualization, conjunction searches and footpoints:http://sscweb.gsfc.nasa.gov/ Thanks to excellent support from SPDF! • Orbit visualization via “tipsod”: a Java – based software

  22. Web-based L2 overview plot distribution (4) http://themis.ssl.berkeley.edu/summary_plots/plot_display.php

  23. Science Readiness Summary • Science Team In Place, Eagerly Awaiting Launch • L0, L1 Automated Science Data Processing In Place • L1 Data Analysis Tools Available for Team and Public • L2 Data Production Routines Based on Past Missions, under construction (Expected before launch) • Web-based Plots, Data and Tools Dissemination in Place • Using I&T data for testing • System in Place for Software Contributions • L2 Data Readily Accessible by SPDF and Cluster • ISTP compatible • Self-documented and readable by QSAS

  24. THEMIS EPO Program Carson City NV UCB • Started yearly teacher workshop site in Carson City, NV in collaboration with LHS • Workshops held in June ’05 and June ‘06 • Installed 13 magnetometers and involved teachers to test lesson plans • Developed, tested & revised Magnetism on Earth teacher’s guide, used now in classrooms • Real-time data on the web • Archived data available on the web Bay Mills College

  25. Magnetometer data at schools Overview • Magnetometers in 13 schools in 10 states • 14+ teachers involved • Teachers leaving mirror lessons at next place • Teacher turnaroud has multiplication effect • Data on the web • Mostly high school classes • Students excited by wiggles and spectrograms • Student research • AGU presentations by students

  26. Education Activities Examples • Background science lessons • Exploring Magnetism and Magnetism on Earth teacher guides • Space Science Weekly Problem • Using data in the classroom • Correlations of magnetism data with other space weather data • Soda bottle Magnetometer comparison to research-grade school magnetometer • Working with Teachers • Maryland Science Center “Teacher’s Thursdays” featured: “Exploring Magnetis Storms and Space Weather with THEMIS”exposing Educator Groups to THEMISAudience: ~30 present, 15 videoconferencing • GEONS Workshops • Local Schools when invited • Leveraging Other activities • THEMIS/GLOBE Workshops, Bay Mills, MI • Mission Observatory, AK • Michigan Science Teacher Association Workshops • Connections with STEREO and RHESSI • Connections with FAST

  27. Public Outreach Examples SAWANO NEWS (WI), Feb-2006

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