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Europa Jupiter System Mission

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Europa Jupiter System Mission Europa Jupiter System Mission Europa Jupiter System • Introduction Ron Greeley Mission • JEO Science Bob Pappalardo • JEO Mission Karla Clark Presentation to the Outer Planet Assessment Group • JGO Science Michel Blanc • JGO Mission Anamarija Stankov November 6, 2008 • Synergies and Wrap-up Michele Dougherty 11/6/08 2 THE EUROPA JUPITER SYSTEM MISSION ASTROBIOLOGY FACTORS 1. Abundant liquid water Theme: The emergence of habitable worlds around gas giants 2. Organics, salts, oxidants, young surfaces 3. Energy Sources: Tidal and Radioactive Decay The Jupiter System = “The Right Stuff” EJSM ADDRESSES EUROPA JUPITER SYSTEM MISSION Jupiter ALL THREE ASPECTS NASA Jupiter Europa Orbiter + ESA Jupiter Ganymede Orbiter • EJSM Study - International Team - Built on previous studies - Community involvement Satellites • Scientifically-rich • Well-defined, mature science • Exploration opportunities • Technology/mission design mature Magnetodisk/ radiation belts EJSM is ready to go! Goal: Explore Europa to Investigate Its Habitability Science of the Objectives: • Ocean & Interior Jupiter Europa Orbiter • Ice Shell • Chemistry & Composition Bob Pappalardo • Geology • Jupiter System Jet Propulsion Laboratory, – Satellite surfaces & interiors California Institute of Technology – Satellite atmospheres – Plasma & magnetospheres November 6, 2008 – Jupiter atmosphere Europa Jupiter System Mission – Rings Presentation to the Outer Planet Assessment Group Europa is the archetype of icy worlds habitability 11/6/08 7 11/6/08 8 JEO Model Payload Europa: Ocean • Ice • Chemistry • Geology Ocean Team Laser Altimeter LA • 11 instruments Ocean & deeper interior: Radio Science RS Ice Team (including radio sci.) • Gravitational tides Astrobiology Ice Penetrating Radar IPR Chemistry Team • Emphasizes Europa • Magnetic environment Vis-IR Imaging Spectrometer VIRIS investigations (including plasma) including UV Spectrometer UVS Ion and Neutral Mass Spectrometer INMS • Robust Jupiter • Surface motion Geology Team system science • Dynamical rotation state Science, Thermal Instrument TI Narrow Angle Camera NAC • Low cost, efficient • Core, rocky mantle, Wide Angle Camera and Medium Angle Camera WAC + MAC & rock-ocean interface Fields and Particles Team teaming approach Magnetometer MAG Interdisciplinary Particle and Plasma Instrument PPI Geophysical techniques give clear answers 11/6/08 Proven technology that does the job 9 11/6/08 10 Europa: Ocean • Ice • Chemistry • Geology Constraining Ice Shell Thickness: Hypothetical Example µice= 10 GPa 1 GPa Ice shell & subsurface Measurement water: Technique: 150 Hypothetical Static gravity • Shallow water range of (density structure) allowable values Tidal deformation • Ice-ocean interface 100 (Love number) A=0.85 Magnetic induction • Material exchange 50 Ocean thickness, km thickness, Ocean ? A=0.75 Radar penetration • Heat flow variations (lower bound) 1 10 100 Ice shell thickness, km Radar sounding will characterize the ice shell Multiple techniques constrain ice shell thickness 11/6/08 11 11/6/08 12 Europa: Ocean • Ice • Chemistry • Geology Europa: Ocean • Ice • Chemistry • Geology Global surface composition Surface features, activity, & chemistry: & landing sites: • Organic & inorganic • Formation history & 3-D chemistry characteristics • Relation to geologic • Recent activity & future processes landing sites • Radiation effects • Erosion & deposition • Exogenic materials Composition is key to understanding Europa’s habitability Europa’s varied and complex geology will be deciphered 11/6/08 13 11/6/08 14 System: Geo • Atm • Mag • Jupiter • Rings System: Geo • Atm • Mag • Jupiter • Rings Satellite surfaces & interiors: Satellite atmospheres: • Tidal heating & heat • Europa: composition, loss variability, dynamics • Io’s active volcanism • Io: sources & evolution • Water in Ganymede & • Ganymede & Callisto: Callisto sources & sinks • Ganymede & Callisto surface materials • Internal evolution & tectonics The Galilean satellites provide context for Europa Understanding atmospheric interactions and processes 11/6/08 15 11/6/08 16 System: Geo • Atm • Mag • Jupiter • Rings System: Geo • Atm • Mag • Jupiter • Rings Jupiter atmosphere: Plasma & magnetospheres: • Minor species abundances • Europa’s escaping neutrals • Dynamics & structure • Io plasma torus • Pickup & charge exchange • Satellite interactions including Ganymede’s field • Magnetospheric structure • Plasma transport Understanding the Solar System’s largest magnetosphere Addresses unanswered questions and complements Juno 11/6/08 17 11/6/08 18 System: Geo • Atm • Mag • Jupiter • Rings Jupiter Europa Orbiter Science Rings: Summary: • Ring source bodies • Ocean characterization • Dynamical processes • Surface-ice-ocean exchange • Compositional makeup • Geological evolution Habitability• Jupiter system science – Galilean satellite evolution – Sat. atmospheric interactions – Magnetospheric physics – Jupiter atmospheric dynamics – Ring system dynamics Comparative studies of ring dynamics and evolution Rich and robust science of Europa and the Jupiter system 11/6/08 19 11/6/08 20 Heritage of Europa Mission Concepts • Europa Orbiter (1997 – 2001) • Jupiter Icy Moons Orbiter (2002-2005) Jupiter Europa Orbiter • Europa Geophysical Explorer (2005) • Europa Explorer (2006) • Europa Explorer (2007) Presented By: • Jupiter System Observer (2007) Karla B. Clark • Laplace Cosmic Vision Proposal (2007) • Jupiter Europa Orbiter Jet Propulsion Laboratory, – Combines EE 2007, JSO 2007 and Europa California Institute of Technology flight element of Laplace November 6, 2008 Europa Jupiter System Mission Presentation to the Outer Planet Assessment Group JEO is the “Just Right” mission for Europa Science 11/6/08 For Planning and Discussion Purposes Only 21 11/6/08 For Planning and Discussion Purposes Only 22 JEO Baseline Mission Overview Highly Capable Model Payload • NASA-led portion of EJSM extensively studied in 2007/2008 • Instruments have operated in Jovian radiation belts Laser Altimeter • Objectives: Jupiter System, Europa before Radio Science • Launch Vehicle: Atlas V 551 • Detector Working Group formed to evaluate radiation • Power Source: 5 MMRTG or 5 ASRG Ice Penetrating Radar aspects of model payload using: • Mission Timeline: Visible-IR Spectrometer • Galileo (and current Juno) experience – Launch: 2018 to 2022, nominally 2020 UltraViolet Spectrometer • Only publicly available technology • Uses 6 year Venus, Earth, Earth gravity assist trajectory – Jovian system tour phase: 30 months Ion and Neutral Ion Spectrometer • Shielding approaches • Multiple satellite flybys: 4 Io, 6 Ganymede, 6 Europa and 9 Callisto Thermal Instrument • Other proprietary options exist (instruments and – Europa orbital phase: 9 months detectors), but inlcuided in performance analysis – End of Prime Mission in 2029 Narrow Angle Camera – Spacecraft final disposition: Europa surface impact Wide and Medium Angle Camera • AO process will select final capability, but Model Payload shows proof of concept for required • 11 Instruments including Radio Science Magnetometer • Optimized for science, cost and risk techniques Plasma and Particle Instrument • Radiation Dose: 2.9 Mrad (behind 100 mils of Al) • 106 kg current best estimate plus 57 kg shielding – Handled using a combination of rad-hard parts and tailored component shielding – Key rad-hard parts are available, with the required heritage – Team is developing and providing design information and approved parts list for prospective Model payload meets science requirements within the suppliers of components, including instruments radiation environment 11/6/08 For Planning and Discussion Purposes Only 23 11/6/08 For Planning and Discussion Purposes Only 24 Spacecraft Mass Operability JEO functionality and mass is comparable to Cassini, with large mass margin Articulated antenna allows simultaneous observations and downlink 11/6/08 For Planning and Discussion Purposes Only 25 11/6/08 For Planning and Discussion Purposes Only 26 Jupiter System Science Io Flyby Example 3 Gb per day average data return – Permits Hundreds of NAC images each day and context images with VIRIS, MAC, UVS, TI ~1000 times more system data return than Galileo Sun Enables observations of dynamic events over long periods of time 11/6/08 For Planning and Discussion Purposes Only 27 11/6/08 28 Io Example Jovian Tour Phase Io Europa Ganymede Callisto • 3 Io Science Flybys • 25% Surface imaged at better than 200m per pixel • Opportunities for sub-surface radar sounding and altimetry • 75 Km Flyby at I4 enables In-situ sample of plume with INMS 11/6/08 29 11/6/08 30 Europa Science Campaigns Risk Reduction Effort Eng Assessment (6d) System Reliability Model 1A 1B Risk Mitigation Plan: 2A 2B Environment and Shielding Model 3 Focused Science: Follow up on discoveries Radiation and Planetary Radiation Design Methods Protection By end of Europa Campaign 3: 4 Sensors and Detectors Parts Evaluation and Testing 4 global maps • Finer global and regional grid of profiling observations Approved Parts and Materials List (APML FY08) - 2 @ 200m Color + Stereo (IPR, VIRIS, TI) - 2 @ 100m Stereo • Continue gravity, laser altimetry, and fields and 730 imaging and radar targets particles measurements 18 km profile spacing for LA and TI • Additional coordinated target sets • Systematic approach to understanding inherent margins 35 km spacing for IPR and VIRIS - Investigate new discoveries and priorities • Practical testing and approval of characterized parts and materials 400 UVS stellar occultations -
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