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1 Open Research Online The Open University s repository of research publications and other research outputs Instruments for in-situ measurements of the gas giants and their satellites Conference or Workshop Item How to cite: Morse, Andrew (2012). Instruments for in-situ measurements of the gas giants and their satellites. In: RAS Specialist Discussion Meeting : Future Exploration of the Outer Planets, 14 Dec 2012, Royal Astronomical Society, London UK. For guidance on citations see FAQs. c 2012 The Author Version: Accepted Manuscript Link(s) to article on publisher s website: Copyright and Moral Rights for the articles on this site are retained by the individual authors and/or other copyright owners. For more information on Open Research Online s data policy on reuse of materials please consult the policies page. oro.open.ac.uk

2 Instruments for in-situ measurements of the gas giants and their satellites A. D. Morse, Planetary and Space Sciences Research Institute, Open University, Milton Keynes, MK7 6AA, U.K.

3 In-situ measurements Advantages: Scale from km to m, mm and mm Ground truth, physical properties Direct analysis of chemical composition

4 In-situ measurements Disadvantages: Short time scale One location Landing high risk Limited payload mass/power Genesis landing

5 Planetary probes Galileo at Jupiter Kronos (cosmic vision 2007) Atmospheric Structure Instrument - Density, pressure temperature Doppler Wind Experiment Nephelometer - aerosol size, shape composition Elemental Composition and isotopes - D/H 13 C/ 12 C 15 N/ 14 N He, Ne, Ar Kr, Xe Heritage Galileo + Rosetta Ptolemy

6 Titan - Huygens Descent Imager and Spectral Radiometer Doppler Wind Experiment Huygens Atmospheric Structure Instrument Surface Science Package Gas Chromatograph and Mass Spectrometer Aerosol Collector and Pyrolyser

7 Titan Atmospheric Chemistry Cassini INMS and CAPS detected organics >10000 amu Cassini at 950km INMS flyby Complex chemistry Titan Energetic particles Ionisation + C 2 H 5, HCNH + + CH 5, C 4 H 5 Molecular CH 4 and N 2 + Dissociation C 2 H 2, C 2 H 4 C 2 H 6, HCN Sunlight Formation pathways? Types of organics? How complex are organics? Are O containing organics formed? Chirality? Benzene (C 6 H 6 ) and other organics( amu) High mass organics >10000 amu Tholins

8 Analysis Organics GC - MS GC separates compounds, identification by MS Sephton et al 1998 Derivatisation required for amino acids and chirality Life Marker chip - ExoMars Target specific molecules High sensitivity ~1.5 kg

9 fulvique pos SIM FT #6-336 RT: AV: 331 NL: 5.08E3 T: FTMS + p ESI SIM ms [ ] C 39 H 49 O16 High Resolution Mass Spectrometry C 38 H 47 O17 90 Time 85 of Flight C 38 H 45 O17 80 Rosetta, ROSINA and COSAC 75 Mass range M/DM C 37 H 41 O C 40 H 53 O15 60 MBToF 55 Mass 50 range M/DM C 37 H 43 O18 SWRI MBToF prototype (Young et al 2008) C 36 H 39 O C 40 H 55 O Orbitrap 35 M/DM C 41 H 57 O C 34 H 31 O C 33 H 27 O22 18 O C 50 H 15 O C 41 H 59 O C 42 H 61 O C 41 H 75 O m/z

10 GC x GC MS Combination of non-polar column followed by polar column H N Pyrrole Methylpyrroles C2 pyrroles GCxGC analysis of tholin sample C3 pyrroles N C4 nitriles C5 nitriles C4 pyrroles C5 pyrroles C3 nitriles MS requirements M >600 amu, F >10Hz M/DM >600

11 Stable Isotopes (1 ) 13 C %o Murchison (CM2) Aromatics > NAP Aromatics < NAP Macromolecule fragments Amino acids Carboxylic acids LMW Hydrocarbons Sulfonic acids 12 C bonds preferably made and broken Carboxylic acids formed by solid phase reactions with carbonates Carbon number 13 C = { - 1 } x1000 ( 13 C/ 12 C) sample ( 13 C/ 12 C) reference

12 Isotopic Analysis Isotope MS Curiosity TDLS Stable magnetic field Simultaneous collection separate ions in space Faraday cup collectors Flat topped peaks Chemical processing Reference material Curiosity, SAM TLS 18 O/ 16 O, 13 C/ 12 C precision ~1 Heritage Pheonix, TEGA Beagle2, GAP (6kg)

13 System diagram Titan Montgolfi è re Chemical Analyser Descent phase Gas inlet Gas inlet Atmospheric inlet inlet Mass Spectrometers Stable Stable Isotope Isotope Ratio MS Ratio MS GC MS GC MS Aerosol Analyser Analyser GCxGC- ToF MS Noble gas gas concentrator concentrator Solid/Gas phase Chemistry Solid/Gas phase Chemistry Elemental/ Isoptopic converter Elemental/ Isotopic Converter GC x GC x GC MEMS MEMS Chemical Chemical Analyser Analyser Sample inlet Wet Chemistry Sample collection systems systems Pyrolysis oven & & Thermochemolysis Wet chemistry & derivatisation & GCxGC, High resolution MS, targeted detection, astrobiology High precision Isotope MS Stable Isotope Ratio MS

14 In-situ measurements at Europa / Enceladus In-situ by orbiter Subterranean ocean No atmosphere Hard surface Europa Enceladus

15 Penetrators In-situ at Europa/Enceladeus Instrumented projectiles Survive high impact speed Penetrate surface ~ few metres An alternative to soft landers Payload Instruments Point of Separation Detachable De-orbit Stage Low mass/lower cost => multi-site deployment Penetrator PDS (Penetrator Delivery System)

16 Penetrator trials Pendine MS Overview Electronics Mass Spectrometer 140 mm Sample Processing System Heritage Rosetta, Ptolemy Mass range amu Unit mass resolution Mass ~ 0.5kg Power 2W

17 Summary Determination of noble gas concentration Measurement of noble gas isotopes Measurement of D/H 13 C/ 12 C, 15 N/ 14 N, 18 O/ 16 O and 17 O/ 16 O isotopes Detailed organic chemical analysis M/DM > and mass range > Possibility of measurements on surface of Europa and Enceladus