Planning for the Scientific Exploration of Mars by Humans By the mepag human Exploration of Mars Science Analysis Group (hem-sag)
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Research Plan At Centauri MontesTwo modes of research would be carried out at CM: Mode 1 — Active gully investigations and local drillingThis mode of research is primarily focused on assessing the recently active gully and other fresh gullies as potential sites of recently water activity, and hence extant life (Figure 23). 
Drill here       
From base camp 
Figure 23. Mosaic of MOC images M04-04175, M20-00028, R14-02285, S10-00142, S11-00332, and S16-01250, colorized using a look-up table derived from Mars Reconnaissance Orbiter HiRISE color data and overlain on a sub-frame of Mars Odyssey Thermal Emission Imaging System (THEMIS) image V16997005.To study the active Malin et al gully, we would: a) Traverse to a site on the crater rim (red X) immediately above the gully and use a deep drill to access the potential volatile reservoir, b) Deploy a human or a “cliffbot” from above to repel to the gully site (blur line) for direct excavation/sampling, and c)Traverse to a point in the crater just below the gully and access the deposits by climbing up to them for direct excavation/sampling. A second drill site on the crater floor would be desirable. 1. Drilling. For this activity horizontal mobility would be minimal, largely dependent on how close to the active gully crater a suitable landing ellipse could be placed. The drill rig would need to be portable enough to be moved from the landing site, to the drill site. Alternatively, it could be moved from the landing site on the rover in pieces and assembled at the drill site. We envision the drill site and landing site to be close enough together that daily commuting could occur between the two. Drill samples (cores and or cuttings) would need to be acquired without drilling fluids (or with clean and sterile fluids) to protect against contamination and alteration and would require suitable on-site storage to keep them protected (as close to their ambient conditions as possible) until such time that they could be moved back to base (presumably the end of each work shift). Once back at base, cataloging, sub sampling and analyses would be done in the hab lab. If there is suitable interest from other disciplines (e.g., geophysics, geology), other (not necessarily as deep) holes could be drilled in the local area for specific goals of geology, geophysics and climate studies. Drill cores would be processed on site for analysis of organics or potential biota by subcoring the main core and maintaining the subcores in sterile conditions. These subcoring methods are similar to those used in deep biosphere research on Earth. Processing on site would minimize the chances of contamination during the transfer of the cores from the field site to the hab or rover lab. 2. Direct measurements and sampling from the active gully. Based on available data, this seems to be achieved most easily by descending to the gully site from above. Samples would be gathered both inside and outside the gully to assess potential for organic/biological enrichment in and under the gully, particularly if it is determined that water was involved in gully formation. 3. Sampling of sediments on the crater floor. The available imagery of the active gully crater (Figure 23) suggests a history of fluid flow through this crater, possibly associated with the gullies. Drilling on the crater floor into some of these sediments, even to shallow depths would be useful for seeking out evidence of past life. Multiple samples would be collected from promising locations. Mode 2 — Sampling TraversesThe second half of the expedition would be spent traversing out to a radius of 50 km away from the landing site to access materials from the three different epochs and collect samples for investigation of past life. Samples would include short cores or grab samples of sediment or rock. For the astrobiology work we would only do minimal analysis in the field and would return many samples to the hab lab for detailed analysis. The main focus is to look for samples which may have preserved biosignatures (e.g., old ice, evaporites, etc.) Horizontal Mobility RequirementsA comparison was done in the region of CM between the scientific benefits of traversing 50 km to a 100 km radial distance from the landing site (Figure 24). In this region, 50 km horizontal mobility seems to be an adequate range given the great diversity of sample sites within this distance. Increasing the horizontal mobility to 100 km does not provide a dramatic increase in new types of terrain. The most significant new terrain type that could be accessed by extending the traverse distance greater than 50 km is the Hesperian Ridged Plains (HRPs). These materials outcrop north of the rim massifs shown in Figure 24 and to access the HRPs the astronauts would likely need to drive around the massif blocks, requiring greater than 50 km driving distance. In addition, the preferred landing site shown in Figure 24 is purposely centrally located. If this landing site is shifted in any direction, a traverse distance of greater than 50 km may be required to access the highest priority science sites. Nonetheless, due to the high concentration of scientifically compelling sites within the 50 km radius, this degree of horizontal mobility would be sufficient for this mission. Furthermore, only half of the mission would be dedicated to traversing, and so a 50 km range should provide ample sampling targets in the limited time. We also recognize a safety constraint on the distance of the traverse. If there are no additional terrain types that are of high priority beyond 50 km then rescue and safety considerations make a 100 km traverse less desirable.  
Figure 24. Comparison of possible traverses with a 50 km (left) and 100 km (right) radius from base camp. Both provide access to numerous deposits/features associated with water (e.g. debris aprons and outflow channels). Both provide access to a similar diversity of terrain types of interest, and most importantly, to deposits from all three major epochs of Martian geology. |