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Vasco da Gama. In Situ Mars Explorer. Scientific Goals. Follow the Carbon Methane, Other Organics Possible association with water Link carbon and geological features to possible extant and extinct life. Roadmap. Precursor Mission & Assumptions Landing site discussion
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Vasco da Gama In Situ Mars Explorer VdG:ISME - July 2004
Scientific Goals • Follow the Carbon • Methane, Other Organics • Possible association with water • Link carbon and geological features to possible extant and extinct life VdG:ISME - July 2004
Roadmap • Precursor Mission & Assumptions • Landing site discussion • Scientific and Technical Justifications • Rover concept • Payload package • Bioscience and Geochemical Science • Summary VdG:ISME - July 2004
Precursor mission • Spaced-based remote sensing (in development) • Avoids terrestrial atmospheric extinction • Spatially resolved measurements of atmospheric CH4 and photochemical products on Mars (Organics Origin Observatory) • Fundamental assumption and problem definition • Precursor space-based mission has spatially resolved methane gradients, focusing the search for carbon reservoirs in potential VdG:ISME landing sites VdG:ISME - July 2004
Landing Sites • Equatorial Meridiani • Relatively near Opportunity • Hale Crater Gullies • 35o S, 324o E VdG:ISME - July 2004
Landing Sites VdG:ISME - July 2004
Scientific Justification: Meridiani • Atmospheric CH4 localization assumed • Interesting even if this is not assumed • Nature of hydrogen detection? • Relatively warm • Surface sulfates, hematite co-localized • Carbonates below these? • Aqueous precipitates can preserve micro-fossils (Squyres 2004, Int’l School for Astrobiology) VdG:ISME - July 2004
Hale Crater Gullies • Again, assumed CH4 (although very tentative “current-day” detections indicate equatorial presence) • Possible water signatures (possible carbonates) • Natural surface excavation • Possible hydrothermal alteration VdG:ISME - July 2004
Malin and Edgett 2000 Gullies VdG:ISME - July 2004
Technical Justification-Landing • Landing error ellipse shrunk to 5km x 10km • Practical, uncomplicated, low-mass methods to increase accuracy • Navigation telemetry from existing positions to increase transverse accuracy • Closed-loop navigation system to respond to sensed variations in atmospheric density (Squyres 2004, personal communication) VdG:ISME - July 2004
Hale Landing • Feasible • Smaller error ellipse • Increased rover range Edgett et al. 2003 VdG:ISME - July 2004
The Rovers • Science payloads identical • Both have slope-climbing abilities • Powered by RTGs • Eliminates low-latitude and nighttime operations as a hazard • Heavier spacecraft, but increases operational parameters • Digging scoop • depth 1m in regolith VdG:ISME - July 2004
Instrumentation • Main body • Pancam copy, Mini mid IR TES (MMIRTES) • Raman analysis and multi-range sensing package (up to 100m) • GCMS • rock-crushing package • Circular Dichroism Filter Set Spectrometer • 96 well culture plates, geared towards autotrophic methanogens VdG:ISME - July 2004
Instrumentation • Manipulator arm • Microscope with fluorescence capabilities • Raman Capabilities (via fibre optics) • Mössbauer • APXS with micron sized mapping • Sample manipulation VdG:ISME - July 2004
Raman • Complements MMIRTES • Organics • Minerals VdG:ISME - July 2004 Ellery & Wynn-Williams 2003
GCMS NAP Signs of Life, Moldowan VdG:ISME - July 2004
H2/CO2 atmosphere shielded from martian surface radiation Moveable 100x microscope Tiny Mars rock (~1mm) 500uL media: Combinations of organic rich, organic poor, nitrates, and phosphates DAPI, (gradual sonication) Light source (for microscopy) VdG:ISME - July 2004
Summary • Precursor methane localization • Twin Rovers • Meridiani & Hale Crater gullies • Rovers • Climbing capabilities • Enhanced power • Enhanced instrument package (Raman, GCMS, Fluorescence) • Dual biological and geological payload VdG:ISME - July 2004