ARTEMIS’s Planetary Goals 1 June 13, 2008 THEMIS Extended Phase = THEMIS baseline + ARTEMIS ARTEMIS Lunar Exploration

ARTEMIS’s Planetary Goals 2 June 13, 2008 THEMIS prime (FY08, FY09) –Overview, orbits, examples of data and discoveries THEMIS Extended Phase (FY10, FY11, FY12) –Extended THEMIS Baseline (3 probes) + ARTEMIS (2 probes) –Acceleration Reconnection, Turbulence and Electrodynamics of the Moon’s Interaction with the Sun The magnetosphere The solar wind The lunar wake –ARTEMIS for Planetary Exospheric Composition, Sputtering Rates Crustal fields – wake deformation Lunar interior sounding Summary Overview

ARTEMIS’s Planetary Goals 3 June 13, 2008 T IME H ISTORY OF E VENTS AND M ACROSCALE I NTERACTIONS DURING S UBSTORMS (THEMIS) RESOLVING THE PHYSICS OF ONSET AND EVOLUTION OF SUBSTORMS PRIME MISSION (FY08 - FY09) 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 FIVE PROBES LINE UP TO TIME ONSET AND TRACK ENERGY FLOW IN THE TAIL

ARTEMIS’s Planetary Goals 4 June 13, 2008 Mission overview: Constellation in excellent health BGS Mission Ops UCB 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) Ground SST ESA EFIa EFIs FGM SCM T spin =3s Release CCAS

ARTEMIS’s Planetary Goals 5 June 13, 2008 Launch= X GSE Y GSE TH-B TH-C TH-D TH-E TH-A P1 P2 P3 P4 P5 First 10 months (Feb 2007-Dec 2007) First year baseline orbit (FY08) Second year baseline orbit (FY09) Prime mission orbits (FY07-FY09) Dayside Tail Dayside Tail

ARTEMIS’s Planetary Goals 6 June 13, 2008 Discoveries Dusk MP Sphere Sheath Sibeck et al., GRL, in press Wang et al., GRL, in press Liu et al., GRL, in press

ARTEMIS’s Planetary Goals 7 June 13, 2008 New results (1 st tail season) Angelopoulos et al. submitted to: Science (embargo in effect)

ARTEMIS’s Planetary Goals 8 June 13, 2008 THEMIS Extension (FY10,11,12)

ARTEMIS’s Planetary Goals 9 June 13, 2008 ARTEMIS (P1,P2): FY10,11,12 FY10: Translunar injection FY11-12: 6mo Lissajous + 17 mo Lunar

ARTEMIS’s Planetary Goals 10 June 13, 2008 ARTEMIS (P1,P2) In the Magnetosphere, study: –Particle acceleration: X-line or O-line? –Reconnection: 3D character and global effects –Turbulence: Drivers and effects Result: –Reveal 3D distant tail, dynamics In conjunction with: –Solar wind monitors: ACE, WIND, STEREO –Inner magnetosphere monitors: Cluster, Geotail, FAST Using the first: –Two point: dX, dY measurements –…at scales from ion gyroradius to several R E

ARTEMIS’s Planetary Goals 11 June 13, 2008 ARTEMIS (P1,P2) Using first of a kind: –…two point measurements at scales 1-10 R E, ideal for study of particle evolution in shocks, at foreshock and inertial range of turbulence In the Solar Wind, study: –Particle acceleration at shocks –Nature and extent of elusive low-shear reconnection –Properties of inertial range of turbulence Result: –Advance our understanding of particle acceleration and turbulence in Heliosphere In conjunction with: –Other solar wind monitors: ACE, WIND, STEREO ARTEMIS is: –High-fidelity solar wind monitor –In beacon mode if requested

ARTEMIS’s Planetary Goals 12 June 13, 2008 ARTEMIS (P1,P2) At the Moon/Wake: –Study 3D structure and evolution of wake Result: –Advance our understanding of wakes at planetary moons, plasma void refilling around large objects (Shuttle, ISS, Hubble). –… to better separate lunar surface and interior signatures in the context of environmental influences Using first of a kind: –…two point measurements at scales R E, ideal for two- point correlations within wake and between wake and solar wind

ARTEMIS’s Planetary Goals 13 June 13, 2008 Exospheric Pickup Ion ARTEMIS-1 ARTEMIS-2 H+H+ He + H2O+H2O+ S+S+ ARTEMIS mass spectrometry of pickup ions plotted as “protons” V ,x V ,y Solar Wind Lunar Exosphere: –Study composition, distribution of exospheric ions Under a variety of solar wind conditions –Comprehensive instrumentation, ample statistics Result: –Advance our understanding of lunar exosphere and its variability –Goes beyond WIND observations ARTEMIS and Lunar Exosphere Hartle et al., 2005

ARTEMIS’s Planetary Goals 14 June 13, 2008 ARTEMIS and Lunar Surface Lunar Surface: –Study composition and distribution of sputtered ions –Understand crustal magnetic fields, surface charging –Remotely sense surface properties of lunar regolith Result: –Advance our understanding of fundamental plasma interactions with planetary surfaces - with applications to Mercury, moons of Jupiter and Saturn, Pluto, KBOs, asteroids, etc. Using first of kind: –…two point measurements of ions and electrons near the Moon, with unprecedented energy coverage and resolution; beyond LP electron reflectometry capability Trace sputtered ions back to lunar surface Secondary and photo-electrons accelerated from charged lunar surface reveal regolith surface properties Secondary electrons measured by Lunar Prospector [Halekas et al. 2008] ARTEMIS

ARTEMIS’s Planetary Goals 15 June 13, 2008 ARTEMIS and Lunar Interior Unanswered questions about the lunar interior –Did the Moon form from a collision of Earth and a Mars size object? –How much of the moon formed from Earth and how from the impactor? –How deep was the lunar magma ocean? Does the Moon have a core? Previous induction studies (Apollo, LP) support the lunar magma ocean hypothesis but are ambiguous due of low signal/noise ratio ARTEMIS’s unique two point measurements allow us to separate external (inducing) and internal (induction response) fields at a wide range of frequencies, with much higher signal/noise ratio –Waves of T~0.1-1hr provide information on crust and upper mantle –Waves of T~1-5 hrs provide information on core (size, conductivity) –Study response to lobe perturbations: shocks and North-South crossings Hood et al. 1999, GRL 1 Core? P1P2

ARTEMIS’s Planetary Goals 16 June 13, 2008 In support of LRO: –ARTEMIS provide comprehensive monitoring of Lunar Space Environment –Complements LRO/CRATER measurements below 200keV Supports LADEE and NAS’s Scientific Content of Exploration of the Moon to: –Understand the lunar atmosphere ARTEMIS and Planetary

ARTEMIS’s Planetary Goals 17 June 13, 2008 THEMIS has delivered on its promises –Major discoveries from coast phase in GRL, JGR, SSR special issues THEMIS+ARTEMIS: Continue to fully embrace community –All Data/Code Open; Help line: THEMIS_Software_Support; Mirror sites proliferating in US, Europe ARTEMIS: Important for Heliophysics ARTEMIS: a new mission with very high science value per dollar –In novel orbits, with comprehensive instrumentation –Has tremendous potential to conduct key Heliophysics science: from the moon –Addresses important Planetary questions: of the moon –Supports major Lunar program missions (LRO, LADEE) Summary