ARTEMIS’s Planetary Goals 1 June 13, 2008 THEMIS Extended Phase = THEMIS baseline + ARTEMIS...
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Transcript of ARTEMIS’s Planetary Goals 1 June 13, 2008 THEMIS Extended Phase = THEMIS baseline + ARTEMIS...
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
TIME HISTORY OF EVENTS AND MACROSCALE
INTERACTIONS DURING SUBSTORMS (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 OpsUCB
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
Tspin=3s
Release
D29
25-1
0 @
CC
AS
ARTEMIS’s Planetary Goals 5 June 13, 2008
Launch=2007-02-17
2007-03-23
2007-06-03
2007-07-15
2007-08-302007-12-04
XGSE
YGSE
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 12008-08-08
Tail 12008-02-02
Dayside 22009-09-16
Tail 22009-02-18
ARTEMIS’s Planetary Goals 6 June 13, 2008
Discoveries
13.0
12.5
12.0
11.5
11.0
10.5
10.0
Y (
R E)
8.0 7.5 7.0 6.5 6.0 5.5 5.0
X (RE)
Magnetosphere
Magnetosheath
30 nT
20 nT
10 nT13.0
12.5
12.0
11.5
11.0
10.5
10.0
Y (
R E)
8.0 7.5 7.0 6.5 6.0 5.5 5.0
X (RE)
A
ED
C
B
Bxy
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 (1st tail season)
P 2 P 1P 3P 4
P 5 T =0Rx
x
X [R ]GSM E
Z [R
]G
SM
E
T =182sCD
T =96sON
T =138sE X M agne to tail lobe
P lasm a shee tN eutral shee t
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
Lunar WakeFormation/Evolution
Diffusive Particle
Acceleration
Shock tangent
Foreshock waves
Turbulent wake?
Last closed field lineGeotail
THEMISMoon
P1P2
P1 P2Solar Wind
X
Magnetotail
ARTEMIS (P1,P2): FY10,11,12
FY10: Translunar injectionFY11-12: 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 RE
ARTEMIS’s Planetary Goals 11 June 13, 2008
ARTEMIS (P1,P2)
• Using first of a kind:– …two point measurements
at scales 1-10 RE, 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 interiorsignatures in the context of environmental influences
• Using first of a kind:– …two point measurements
at scales 0.1-10 RE, ideal for two-point correlations within wake and between wake and solar wind
ARTEMIS’s Planetary Goals 13 June 13, 2008
ExosphericPickupIon
ARTEMIS-1
ARTEMIS-2
H+
He+H2O+ S+
ARTEMIS mass spectrometryof 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 ionsback to lunar surface
Secondary and photo-electronsaccelerated from charged lunar surfacereveal regolith surface properties
Secondary electronsmeasured by LunarProspector [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?
P1 P2
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