Astrobiology Field Laboratory - Science

Science

Though the AFL science justification did not include a pre-definition of potential life forms that might be found on Mars, the following assumptions were made:

1. Life utilizes some form of carbon.
2. Life requires an external energy source (sunlight or chemical energy) to survive.
3. Life is packaged in cellular-type compartments (cells).
4. Life requires liquid water.

Within the region of surface operations, identify and classify Martian environments (past or present) with different habitability potential, and characterize their geologic context. Quantitatively assess habitability potential by:

• Measuring isotopic, chemical, mineralogical, and structural characteristics of samples, including the distribution and molecular complexity of carbon compounds.
• Assessing biologically available sources of energy, including chemical, thermal and electromagnetic.
• Determining the role of water (past or present) in the geological processes at the landing site.
• Investigate the factors that will affect the preservation of potential signs of life (past or present) This refers to the potential for a particular biosignature to survive and therefore be detected in a particular habitat. Also, post-collection preservation may be required for later sample retrieval, although that would necessitate a further assessment of precision landing of Mars sample return mission mission.
• Investigate the possibility of prebiotic chemistry on Mars, including non-carbon biochemistry.
• Document any anomalous features that can be hypothesized as possible Martian biosignatures.

It is fundamental to the AFL concept to understand that organisms and their environment constitute a system, within which any one part can affect the other. If life exists or has existed on Mars, scientific measurements to be considered would focus on understanding those systems that support or supported it. If life never existed while conditions were suitable for life formation, understanding why a Martian genesis never occurred would be a future priority. The AFL team stated that it is reasonable to expect that missions like AFL will play a significant role in this process, but unreasonable to expect that they will bring it to a conclusion.