Planning for the Scientific Exploration of Mars by Humans By the mepag human Exploration of Mars Science Analysis Group (hem-sag)

Vertical Mobility Requirements

For biological investigations we would need vertical mobility to:

a) Investigate the groundwater hypothesis for recently reported active gullies on Mars (Malin et al. 2006). Several researchers have suggested that a shallow subsurface aquifer may be the source of the liquid water feeding the martian gullies (Malin and Edgett 2000; Mellon and Phillips 2002; Heldmann and Mellon 2004; Heldmann et al. 2007). In this scenario, a liquid water aquifer exists beneath the upslope plateau behind the gullies at a depth coincident with (or near to) the gully alcove base depth. The average alcove base depth in the southern hemisphere is ~200 meters poleward of ~40° and thus a drill capable of reaching several hundred meters depth would be required in order to reach the subsurface aquifer. To account for any uncertainties and/or heterogeneities in the subsurface as well as the natural variation in alcove depths within different gully systems, a drill capable of reaching greater than 250 m depth (preferably 400-500 m) would be desirable.

b) Investigate other fresh gully sites (Heldmann unpublished) near the landing site. Likely the same penetration depths as a) are required here.

c) Drill directly into gully sites to 5 m.

d) Drill (5-50 m) while doing longer traverses to collect samples from below the high radiation and oxidant surface region for ancient or dormant life in ground ice and other water lain deposits.

We envision two drills to achieve these goals. One would be heavy and not very portable (for a and b). The second would be more portable and lightweight with the option to be mounted on the rover for the deeper penetrations, and detached and manipulated directly by astronauts for the shallower work in rough terrain. Examples of this type of arrangement already exist for terrestrial prospecting (Figure 25).


Figure 25. Image of ARGO vehicle that can be equipped with either a hydraulic or pneumatic drill mast that can drill 2-4 in. diameter holes up to 60 m deep in rock formations ranging from sedimentary to metamorphic. And for further flexibility, the drill can be detached from the ARGO and used in man-portable mode. From http://argoatv.com.

Science Capabilities Required

To accomplish level 1 the rover should offer basic mobile laboratory capabilities. However, the logistics of operation in a confined rover space in the field probably militate against including large quantities of equipment. Further, from a purely logistical standpoint, field experiments should be limited to those required on site to select samples etc. Considerations of safety and limited time in the field mean that carrying out detailed laboratory investigations in a rover would likely to be undesirable.

Level 2 should be accomplished at the habitat. In a fixed location free of the constraints of EVA activity much more detailed and painstaking analysis of samples could be accomplished. For example, precise dating of samples, which wouldl be extremely helpful in determining the geological and environment history of sampling sites and hence guiding sample selection, would be best done on isolated mineral phases physically separated from hand specimens. Such separation would be most efficiently done by astronauts. The quality of data for some isotope systems would also be enhanced by sample preparation procedures that couild be difficult to automate and package for robotic exploration.

Two laboratories would likely be needed. A medical/planetary protection laboratory would be used for human health monitoring and medical treatment as well as monitoring of the microbial ecology of the habitat and the region around it as part of a general planetary protection protocol/survey. However, to minimize the chances of cross-contamination this lab should be separated from a second laboratory used for extant/extinct life investigations. Separating the two laboratories would help prevent false positive detection of martian life and it would reduce the chances of astronauts coming into contact with organic material from Mars.

Rover

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  Rover mounted drill
  
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  Seismic sounding equipment (to facilitate local sounding and locate the most promising drill targets)
  
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  Field microscope
  
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  LIBs and field tele-raman (if a portable package could be made for rovers to carry this would be better)
  
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  Ability to monitor the effectiveness of separation between humans and the environment
  
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  Ability to monitor bioload — contamination of the environment or tools to ensure sample integrity. Basic biological ‘dipstick’ tests for major groups of human-derived organisms
  
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  GPR
  
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  Equipment to measure major cations and anions in water extracts.
  
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  Portable XRF and XRD
  
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  Radiation measurement tools (UV-Vis spectrometers and dosimeters)
  
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  pH and Eh meters (to examine water extracts of soils and rocks)
  
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  Sample containers and handling tools
  
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  Basic meteorology equipment (temp, pressure, light)
  

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  Multispectral imager
  
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  Rock hammer and sample bags
  
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  Hand lens and/or lens imager
  
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  Digital camera
  
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  Handheld XRF/XRD
  
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  Portable field microscope with camera
  
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  Hand-held spectrometer — Raman (available at the moment)
  
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  Soil water/ice content measurement device
  
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  Sample logging equipment — preferably automated in some fashion.
  
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  A portable microarray system
  
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  Shovel
  

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  Panoramic camera
  
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  Microscopic camera
  
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  Raman spectrometer for mineralogy logging
  
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  Magnetic susceptibility detector
  
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  Environment physicochemical subsurface probes (pH, eH, T, C, ions)
  
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  Gas-meter in subsurface
  
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  Subsurface water sampler (is important to maintain the water sample under the original P conditions)
  

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  Lab isolation unit to allow astronauts to work on samples (probably separate from hab) — ability to sterilize certain work areas I.e. laminar flow hoods for biological investigations
  
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  Basic lab equipment for planned and spontaneous research (drying oven, furnace, scales, etc.)
  
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  High-end raman spectrometer with mapping capability — multiwavelength perhaps combined with same spot laser induced fluorescence or FTIR
  
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  Tabletop SEM
  
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  High precision mass spectrometers for isotopic analyses of possible biosignatures, environmental indicators and for geochronology
  
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  GC and GC mass spec (plus auto-extraction system) and laser ablation ToF
  
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  Bright field and fluorescence microscopy
  
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  Confocal raman microscopy
  
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  XRD/XRF eventually coupled to SEM
  
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  Equipment for sample prep (rock saws, mills, etc.)
  
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  General chemistry equipment for sample preperation and analysis.
  
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  Equipment for nucleic acid extraction (assuming any Martian life have nucleic acids) and some sequencing capability (note this same equipment is need for human health monitoring and microbial ecology analysis of habitat)
  
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  Screening for biomolecules (electron transport molecules, various key proteins, phospholipids, etc.) using microarray assays and other lab on a chip/miniaturized biomolecule detection instruments
  
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  Basic metabolic analysis/culturing equipment (Viking style experiments, but using non-organic redox couples)
  
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  Basic and fluorescence staining for biomolecules