Vasco da Gama

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Vasco da Gama

• In Situ Mars Explorer

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Scientific Goals

• Follow the Carbon
• Methane, Other Organics
• Possible association with water
• Link carbon and geological features to possible
  extant and extinct life

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Roadmap

• Precursor Mission Assumptions
• Landing site discussion
• Scientific and Technical Justifications
• Rover concept
• Payload package
• Bioscience and Geochemical Science
• Summary

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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 VdGISME
  landing sites

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Landing Sites

• Equatorial Meridiani
• Relatively near Opportunity
• Hale Crater Gullies
• 35o S, 324o E

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Landing Sites
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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, Intl School for Astrobiology)

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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

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Gullies
Malin and Edgett 2000
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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)

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Hale Landing

• Feasible
• Smaller error ellipse
• Increased rover range

Edgett et al. 2003
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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

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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

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Instrumentation

• Manipulator arm
• Microscope with fluorescence capabilities
• Raman Capabilities (via fibre optics)
• Mössbauer
• APXS with micron sized mapping
• Sample manipulation

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Raman

• Complements MMIRTES
• Organics
• Minerals

Ellery Wynn-Williams 2003
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GCMS
NAP Signs of Life, Moldowan
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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)
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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