Work begun during Phase II continued during Phase III in the laboratory. Dry swab samples taken during EVA 31 produced a few colonies on rich medium, but only from the bottoms of rocks. While there probably are many species residing on the topsides, which are exposed to UV and extreme temperature change, they may be dormant, viable but not culturable, or inhabit crevices not reached by this sampling method.

During EVA 48, Jon Clarke collected larger samples under the overhang corresponding to some of the sterile-collected biological samples. These were examined with the PIMA in the laboratory. Gypsum, montmorillonite, and anhydrite were the most prevalent minerals. Interestingly, carbonates were only found in the layer which supported a luxuriant moss growth and in the layer with a blue-black deposit.

A few grains of all of the samples were dry-spotted to both rich and minimal medium and incubated at 30-33°C in dim light. On rich medium, all of the samples showed a vigorous outgrowth of a highly motile bacterium, which promptly overgrew all other colony types. Further analysis will be required to identify other species in these samples capable of growth under these conditions. At this point, there is evidence of slow growth around some samples on minimal medium.

Radioactive areas are present in the vicinity of MDRS, and represent another type of microhabitat which might yield uniqe organisms. While uranium deposits such as those in southern Utah are unlikely on Mars, strong UV and cosmic radiation might select for life forms able to withstand or possibly utilize this energy. Consequently, Jon, Stan, and I set off to find a uranium prospect identified on a map, and succeeded in finding an abandoned works with considerable tailings. Selected areas of the debris pile showed low-level radioactivity. A more complete description of the minerals is covered in Jon's Geology report of March 7. The most interesting site was a piece of petrified wood, which showed the highest level of radioactivity. When it was split with a geology hammer, small flecks of a coal-like material were present inside, also radioactive with a Geiger counter.

When samples were dry-plated on rich medium as discussed above, growth appeared promptly in all of the samples. What was most interesting, however, was a luxurient white fungal mycelium growing out from the radioactive black material in the petrified wood. No such fungal growth appeared in any other sample collected during ExOne. Further analysis of these and other samples collected will take place on Earth, since there was not enough time to do more in the Hab laboratory.

A major goal during Phase III was to test and compare the research capabilities of the two specially-designed research rovers, the Ares and the Everest, and a SUV-PEV. The operational details of these three trials are described in the EVA reports. From the point of view of biological and other field studies, research rovers are an enormous advantage. The most important reason for having a rover with at least minimal research capability is that samples can be examined in the field for interest and relevance -- is this pay dirt or not? If it is, then samples can be stored, incubated, etc., for further analysis, and if it is not of interest, then the sample can be discarded right away while moving on to more productive sites.

While these vehicles are prototypes, it was very interesting to see how their various features performed in the field, and what improvements in design, many of which are fairly simple to implement, would benefit their operation. One of the major strengths of ExOne was that field scientists could work with engineers under realistic conditions to develop the technology required for crewed exploration of Mars. Major advances, in addition to the rovers, were the MCP (mechanical counter pressure) suits, which were much less cumbersome than the MDRS pressure suits, and the datalogger, which should evenually eliminate the need for field notebooks. Given that the payload will be severely limited, we need to design technology that fits together to achieve our goals.