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Astrobiological Signatures with Penetrators on Europa. Rob Gowen (MSSL/UCL, UK) on behalf of Penetrator Consortium.
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Astrobiological Signatures with Penetrators on Europa Rob Gowen (MSSL/UCL, UK) on behalf of Penetrator Consortium Alan Smith1, Richard Ambrosi6, Olga Prieto Ballesteros16, Simeon Barber2, Dave Barnes11, Chris Braithwaite9, John Bridges6, Patrick Brown5, Phillip Church10, Glyn Collinson1, Andrew Coates1, Gareth Collins5, Ian Crawford3, Veronique Dehant21, Michele Dougherty5, Julian Chela-Flores17, Dominic Fortes7, George Fraser6, Yang Gao4, Manuel Grande11, Andrew Griffiths1, Peter Grindrod7, Leonid Gurvits19, Axel Hagermann2, Tim van Hoolst21, Hauke Hussmann13, Ralf Jaumann13, Adrian Jones7, Geraint Jones1, Katherine Joy3, Ozgur Karatekin21, Günter Kargl20, Antonella Macagnano14, Katarina Miljkovic 7,Anisha Mukherjee5, Peter Muller1, Ernesto Palomba12,Tom Pike5, Bill Proud9, Derek Pullan6, Francois Raulin15, Lutz Richter18, Keith Ryden2, Simon Sheridan2, Mark Sims6, Frank Sohl13, Joshua Snape7, Paul Stevens10, Jon Sykes6, Vincent Tong3, Tim Stevenson6, Werner Karl5, Lionel Wilson8, Ian Wright2, John Zarnecki2. 1: Mullard Space Science Laboratory, University College London, 2: Planetary and Space Sciences Research Institute, Open University, UK. 3:Birkbeck College, University of London, UK. 4: Surrey Space Centre, Guildford, UK. 5: Imperial College, London, UK, 6: University of Leicester, UK. 7: University College London, UK. 8: LancasterUniversity, UK. 9: Cavendish Laboratory, Cambridge, UK. 11: University ofAberystwyth, UK. 12: Istituto di Fisica dello Spazio Interplanetario-INAF, Roma, Italy. 13: DLR, Berlin, Germany. 14: Institute of Microelectronics and Microsystem-CNR, Roma, Italy. 15: Université Paris, France. 16: Centro de Astrobiologia-INTA-CSIC, España. 17: Abdus Salam International Centre for Theoretical Physics (ICTP), Trieste, Italy. 18: DLR, Bremen, Germany. 19: Joint Institute for VLBI in Europe (JIVE), Dwingeloo, The Netherlands. 20: IWF,Space Research Institute, Graz, Austria. 21: Royal Observatory, Belgium
Contents • Mission to Europa • Europa • Penetrators • Instruments • Astrobiology • Conclusions
Contents • Mission to Europa • Europa • Penetrators • Instruments • Astrobiology • Conclusions
Mission to Europa • EJSM – joint ESA/NASA mission to Jovian system. • JEO – Jupiter/Europa Orbiter (NASA element) • launch nominally 2020 • arrive Europa 2028 • observe 9 months (heavy radiation) may include penetrators…
Spin-Down Descent Module release from Orbiter Spin-up & Decelerate Reorient Penetrator Separation Penetrator & PDS surface Impact Penetrator delivery Delivery sequence courtesy SSTL Operate from below surface
Basic parameters • mass : 0.7 Moon • surface gravity : 0.8 Moon • radius : 0.9 Moon • orbital period : 3.5 day • surface temp : 40-120K • surface radiation : Mrads Europa Astrobiology potential ? • atmosphere – trace Oxygen (10-12 Earth) • surface material - water ice • strong tidal forces • subsurface ocean ? • rocky ocean floor bottom • habitable ? • life ?
surface features Japanese Lunar-A Continuous launch delays Several paper studies
high resolution 10Km
Accessing Astrobiological Material • upwelled material available in striations from ocean beneath (may contain astrobiological material) • evidence of sulphates in striations. • young surface: 5-60 Ma(minimise radiation and meteroid damage) • but surface mostly very rough Image from Proctor (JHU), Patterson (APL) & Senske (JPL) (2009, Europa Lander Workshop, Moscow)
From Proctor (JHU), Patterson (APL) & Senske (JPL) (2009, Europa Lander Workshop, Moscow)
Impact Site Characteristics Based on Proctor (JHU), Patterson (APL) & Senske (JPL) (2009, Europa Lander Workshop, Moscow)
Vertical exagguration x20. Vertical height ~ 1km. Landing ellipse ~5km into smooth area, equatorial From Proctor (JHU), Patterson (APL) & Senske (JPL) (2009, Europa Lander Workshop, Moscow)
Micropenetrator & Instruments • Low mass [~5-15Kg] • Very tough [~100-500m/s, impact ~10-50kgee] • Perform science from below surface [~0.5-few m] ~20-60cms
Post Impact • Target area of upwelled material (astrobiology) • ~0.5 to few metres below surface (reduced radiation) • 2 penetrators - derisk/improve performance • Lifetime: few hours (geochemistry/astrobiology, soil properties) to few orbits (seismic measurements)
Instruments and TRL • Previous Mars96, DS2, Lunar-A developments • UK currently developing technology for lunar mission • Most instruments have existing space heritage. • + successful full scale impact trial in UK. Prototype, ruggedized ion trap mass-spectrometer Open University (Rosetta) Micro-seismometer Imperial College (ExoMars)
Impact trial – internal architecture Mass spectrometer Radiation sensor Batteries Magnetometers Accelerometers Power Interconnection Processing Micro-seismometers Accelerometers, Thermometer Batteries,Data logger Drill assembly
Trial Hardware Inners Stack
Impact Trial - Configuration Rocket sled Penetrator
Target Dry sand 2m x2m x6m Small front entrance aperture (polythene)
Any life on Europa?? Radiation from Jupiter’s magnetosphere forms oxidants at surface that could be used as food source Comets deliver organics 10cm radiation danger Habitable zone Photosynthetic plants could take advantage of sunlight Clinging life forms could use food brought by current Floating forms could move up and down with the tides Strong daily tidal currents Adapted from ‘Biogeochemistry of the Europa icy surface’, by Katarina Miljkovic, OU Feb’07 Warm ocean Image: University of Arizona, Lunar and Planetary Laboratory
Adapted from K.Hand et. al. Moscow’09, who adapted it from Figueredo et al. 2003 3. astrobiological spectral signatures 2. communication of life forms to surface 1. habital zone on ocean floor adjacent to nutrients Another model…
Astrobiology Signatures ? • Presence of habitat • Body image and motion • Organic chemical inventory and proportions • Isotopic ratios (sulphur) (weak spectral component ) • Spectral signatures (complex)
Astrobiology Investigations • Microseismometers/Radio beacon/Magnetometer- Determine existence and characterise potentially habitable subsurface ocean. • Chemical sensing – via sample acquisition or e.g. stand-off laser ablation (mass spectrometer, quartz micro-balance and electronic noses, etc…) • mass spec can determine presence of organic molecules and their relative abundances. • mass spec can determine 32S/34S isotopic ratio which is expected to have quite different value whether origin is biological or geological.(very difficult to detectable spectrally) • Spectral sensing – remote (but close) chemical determination.(don’t yet have candidate instrument for spectral signal !) Raman. • Astrobiology imager – view either remote or acquired sample. Image life forms but more likely look for uv fluorescence (RNA/DNA)
Questions ? • What does discovery of a rejected grant application form mean ? • How many different measurements to prove life ? • What are best measurements to make to prove life ? • 2 penetrators better than 1 ?
Conclusions • Earth is only body currently known to contain life... • Detection of biosignatures on Europa or exoplanet could inform other field. • Detection of life on Europa or exoplanet could inform other field. • Heavy surface radiation is not necessarily an impediment to life. • Penetrators may also detect biosignatures on other planetary bodies (e.g. Moon, Mars). • Are there any other commonalities/useful connections with in-situ search for astrobiological signals ? • Good luck with hunting astrobiology signals from exoplanets !
- End - rag@mssl.ucl.ac.uk http://www.mssl.ucl.ac.uk/planetary/missions/Micro_Penetrators.php