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Solar System Exploration and Research on Icy Moons at the German Aerospace Center Oliver Funke

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Solar System Exploration and Research on Icy Moons at the German Aerospace Center Oliver Funke DLR.de • Chart 1 > PPOSS 2017 > Funke > 23.01.2017 Solar system exploration and research on icy moons at the German Aerospace Center Oliver Funke DLR - German Aerospace Center Space Administration | Navigation DLR.de • Chart 2 > PPOSS 2017 > Funke > 23.01.2017 Sketch of DLR and given constraints Germany’s national aeronautics and space research centre DLR aeronautics space energy transport security R&D Space Space DLR Space Administration (Bonn): planning and implementation Administration of the German space programme representation of Germany‘s interests at ESA research funding agency BMWi Federal Ministry of Economic Affairs Funding of DLR R&D and Energy not allowed ! DLR.de • Chart 3 > PPOSS 2017 > Funke > 23.01.2017 DLR Space Administration Dept. of Navigation: Overview DLR.de • Chart 4 > PPOSS 2017 > Funke > 23.01.2017 DLR Space Administration Dept. of Navigation: Programme lines 1. GNSS applications and new services (RTK receiver, RAIM technologies) 2. Space segment and payload (Galileo next generation technologies) 3. Innovative new technologies for navigation: autonomous navigation (AI), sensor fusion, … development of key technologies for navigation required for future space missions: inititation of projects (also on basis of own ideas) at least 60% navigation context up to 40% other required aspects (e.g. adequate technology carrier, …) generation of terrestrial spin off applications DLR.de • Chart 5 > PPOSS 2017 > Funke > 23.01.2017 Jupiter‘s and Saturn‘s Icy Moons • Jupiter‘s moon Europa: global water ocean beneath thick (up to several 10 km) layer of ice • Technical challenge: How to access and explore the ocean? First approach suggestion by Zimmerman et al. (NASA/JPL): Cryobot: An Ice Penetrating Robotic Vehicle for Mars and Europa Published in: Aerospace Conference, 2001, IEEE Proceedings. (Volume:1) Artists impression of Europa‘s ocean. Credit: NASA/JPL-Caltech DLR.de • Chart 6 > PPOSS 2017 > Funke > 23.01.2017 Cryobot and Hydrobot Prototype of the Cryobot Credit: NASA/JPL Artists impression of cryobot and hydrobot in Europa exploration scenario. Credit: NASA/JPL DLR.de • Chart 7 > PPOSS 2017 > Funke > 23.01.2017 Two category IV future missions: EurEx and EnEx Feasibility analysis and first developments initiated and funded by DLR Space Administration DLR.de • Chart 8 > PPOSS 2017 > Funke > 23.01.2017 EurEx – Europa Explorer GPHS RTG within surface lander, Initial project phase 2012 - 2015 energy to Teredo is transmitted by cable connection Legend to image on the right: 0 Melting Probe (MP) IceShuttle „Teredo“ 1 Autonomous Underwater Vehicle (AUV) „Leng“ 2 decend of AUV 3 acoustic navigation concept and exploration phase of sea ground 4 ascending phase of AUV, returning to Teredo base 5 data communication to Teredo Early stage EurEx mission concept. Credit: DFKI DLR.de • Chart 9 > PPOSS 2017 > Funke > 23.01.2017 EurEx Status after initial phase first prototypes of Teredo and Leng docking mechanism acoustic navigation with Microgliders advances in autonomy first mission analysis and visualization by simulation tool appropriate landing sites discussed follow up phase „EurEx Phase 2“ planned: further steps in navigation + autonomy miniaturization of AUV and MP proof of concept in Arctic field test Credit: DFKI DLR.de • Chart 10 > PPOSS 2017 > Funke > 23.01.2017 EurEx Landing sites Thera Macula: supposed subglacial lake on Europa Ivanov, M.; et al., Landforms of Europa and selection of landing sites, Advances in Space Research: 661-677, 2011 Direct access to Europa‘s ocean not envisaged due to technical limitations: power supply transmittance refreezing melting hole cable connection got to be implemented into MP strong Thera Macula limitation for cable length! Credit: NASA DLR.de • Chart 11 > PPOSS 2017 > Funke > 23.01.2017 Cassini at Enceladus Saturn‘s moon Enceladus. Credit: NASA/JPL/Space Science Institute 2005: discovery of active cryovolcanism ! Ice particles blown into space several 100 km Passing through ejected ice particles revealed presence of organic compounds within! Ice fountains originate from subglacial ocean Thickness of surface ice crust up to 35 km Artists impression of Enceladus‘ ocean. Credit: NASA/JPL-Caltech DLR.de • Chart 12 > PPOSS 2017 > Funke > 23.01.2017 EnEx – Enceladus Explorer Initial project phase 2012 - 2015 Basic idea: sampling of upwelling water in a cryovolcano feeding crevasse at a depth of 100 to 200 m Project tasks: utilisation of a melting probe with fully 3D maneuverability the IceMole of FH Aachen development of 3D navigation in-situ decontamination sampling ability preliminary first mission design field test validation in First prototype of the IceMole Credit: FH Aachen terrestrial “Enceladus-similar” environment DLR.de • Chart 13 > PPOSS 2017 > Funke > 23.01.2017 The Joint Project EnEx Feb 2012 – Mar 2015 Partners: • FH Aachen • Universität der Bundeswehr München • TU Braunschweig • Universität Bremen • RWTH Aachen • Bergische Universität Wuppertal Associated collaboration with MIDGE project (J. Mikucki, S. Tulaczyk): Minimally Invasive Direct Glacial Exploration (NSF funded) Successive field tests at Swiss Alps, 2013 first test on Canada glacier, Antarctica Final field test in Antarctica Nov/Dec 2014 DLR.de • Chart 14 > PPOSS 2017 > Funke > 23.01.2017 The EnEx-IceMole DLR.de • Chart 15 > PPOSS 2017 > Funke > 23.01.2017 Blood Falls, Antarctica A terrestrial Enceladus like Scenario Credit: NSF DLR.de • Chart 16 > PPOSS 2017 > Funke > 23.01.2017 Concept of Field Test Blood Falls at Taylor glacier, Antarctica Dachwald et al. in Annals of Glaciology 2014 (modified slightly by Funke) DLR.de • Chart 17 > PPOSS 2017 > Funke > 23.01.2017 Clean Sampling Preparation of EnEx-IceMole in Lab before shipping to Antarctica Photos courtesy of Ilya Digel, FH Aachen/Jülich DLR.de • Chart 18 > PPOSS 2017 > Funke > 23.01.2017 Green light for Blood Falls field test DLR.de • Chart 19 > PPOSS 2017 > Funke > 23.01.2017 S U C C E S S First ever extraction of samples from Blood Falls Photos courtesy of EnEx field test team, FH / RWTH Aachen DLR.de • Chart 20 > PPOSS 2017 > Funke > 23.01.2017 Technical Conclusions and Continuation EnEx-IceMole prooved basic mission concept Localization and navigation capability successfully demonstrated In-situ decontamination successful in terrestrial field test Continuance phase started in 2015 with variety of single projects Focus on full autonomy of probe enhanced sensor ranges high level computer simulation Photo courtesy of EnEx field test team, FH / RWTH Aachen HW tests in vacuum miniaturization of EnEx-IceMole DLR.de • Chart 21 > PPOSS 2017 > Funke > 23.01.2017 The „EnEx – Enceladus Explorer Initiative“ • Coordination and funding of the individual projects by DLR Space Administration • Close internal collaboration across departments: Navigation Microgravity Research and Life Sciences Human Spaceflight, ISS and Exploration General Technologies and Robotics www.dlr.de/rd/EnEx Purpose: Demonstrate technical feasibility and propose EnEx and/or EurEx like missions to ESA EurEx is part of the (time horizon for mission at target: 204x) EnEx Initiative DLR.de • Chart 22 > PPOSS 2017 > Funke > 23.01.2017 PPOSS relevant results and open questions Lessons learnt (+ positive / – negative) (+) Project results indicate that collection of englacial samples for microbiological analysis is feasible with melting probes. (+) Successful retrieval of uncontaminated subglacial samples will provide an important example for the clean exploration of icy environments on Earth and their potential for the use of this technology for future icy body exploration missions. (-) The method of recovering microorganisms from different solid surfaces is critical for reliability and objectivity of sampling and microbiological risk assessment. Today, sampling by cotton or rayon swabs is undeservedly considered the “gold standard”. In our study, traditional swab-based methods were found to be inaccurate, time consuming and prone to significant variations due to uncontrollable contribution from multiple factors, including (a) operator qualification; (b) sampling room conditions; (c) swab material; (d) microorganism’s type and (e) surface roughness. There is a necessity in development of alternative sampling methods, corresponding fulfilling to the current requirements to efficacy, accuracy and reproducibility. DLR.de • Chart 23 > PPOSS 2017 > Funke > 23.01.2017 PPOSS relevant results and open questions Lessons learnt (+ positive / – negative) (-) Even in the absence of viable microorganisms after microbiological disinfection was done, some of their biochemical components persistently remain on the treated surfaces. In particular, lipopolysaccharides (LPS) represent an extremely problematic component of the remaining bioload. Can the EnEx concept be expanded for implementation of GPHS-RTG power supply unit into EnEx-IceMole? Can be considered to implement GPHS-RTG into EurEx-AUV? If so, safety requirements and other constraints have to be defined and evaluated.
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