Overview

Experimental Design

Due to the high generality inherent with our definition of life, we could not directly derive our experiments to test it.  Quite simply, the experiments do not exist to fully and conclusively test such a general definition.  Instead, we formed a series of assumptions that can be made about Mars life, and derived experiments from the results of these assumptions.  The situation is somewhat different for experiments looking for fossil life, since the generally accepted definition of fossil life is very specific.  Thus, the experiments searching for fossils can be derived directly from the definition of fossil life, and required no such set of assumptions. 

With every assumption we make to derive experiments, though, we open loopholes through which evidence of Martian life may pass.  This danger can be sidestepped, however, if we make sure of two characteristics of our experiments.  First, they must be capable of testing our assumptions, so that we will know if any of our loopholes are open.  Second, they must be adaptable to different situations, so that any open loopholes can be closed while the mission is in progress.

The thought process behind the experiments is outlined in both graphical and table format:

Flowchart of Assumptions, Supporting Facts, and Derived Experiments

Table of Assumptions, Supporting Facts, and Derived Experiments

Once again, the ideas behind the experiments looking for fossils are made much clearer by the specific nature of the definition of fossil life.  The conditions for a structure to be a fossil divide neatly into three categories.  The first contains the first five conditions discussed under the definition of life.  These conditions are all met through visual analysis, suggesting the preparation and analysis of petrographic thin sections.  The second consists of the condition that the host rock must have formed under conditions favorable for life.  This suggests a basic field analysis to determine the mineral composition of the rock, which can be done by a trained geologist with minimal tools and so will not be discussed further in this report.  The final category consists of the final condition for a fossil, that of a characteristic isotope ratio.  This condition can be determined by mass spectroscopy of the fossil-bearing rock.