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Center for the Study of Biomarkers in Astromaterials

The uniting theme for the Johnson Space Center (JSC) Team is astrobiology-related sample and material analysis to provide characterization data on terrestrial samples, astromaterials, and experimental samples. The types of data sought from these samples are usually features related to microbial life. Such features include morphology of living microbes and their surroundings including biofilms, as well as the morphology of fossilized forms of these living biota. In addition to morphology, the chemistry and mineralogy of microbial produced features and fossilized microbes are of great interest to the Johnson Space Center Team. For this work the JSC group typically use probe instruments (SEM, TEM, electron microprobes, TOF-SIMs, double laser beam mass spectrometers) to acquire information on living or fossilized microbial structure. Their overall objective is to relate chemistry, mineralogy, atomic structure, morphology, spectral interactions, and other properties for specific types of features so that multiple data can be used to characterize or fingerprint life in all its forms, to include ancient fossils and bioassisted mineral precipitates.

In addition, the Johnson Space Center Team seeks to understand the processes that create the characteristics of life, the processes that alter or fossilize life, and the processes that produce and preserve interaction between life forms and rocks or minerals. Fingerprints of life are valuable for themselves, but they may also contain the history of that life and its environment over time.

The ability to confidently identify the presence of life or the former presence of life has been taken for granted in many types of terrestrial samples. However, as researchers begin looking more and more at astromaterials from beyond earth (and also take a fresh look at archean samples on earth), the scientific community has realized that it is not always obvious or easy to determine whether life was or is present in the rocks, minerals, soils, and fluids of earth or another planet. Consequently, a major goal of the Johnson Space Center Team is to develop better techniques for detecting and understanding life, as this capability will be required for future sample-return missions to Mars. The JSC Team proposes, though, that these techniques should first be well tested on terrestrial samples, and that they should also be applied to other types of astromaterials as well, such as meteorites, cosmic dust, cometary dust, and samples from various satellites and small bodies. Because of the extreme interest in and significance of discovering life elsewhere than on Earth, these techniques must be developed to include strong verifiable detection criteria.

The specific projects within the Johnson Space Center Team are:

• The Mars Immunoassay Life Detection Instrument (MILDI), for possible robotic missions to Mars, Titan, and other NASA targets
• Hematite on Mars: Possible biogenic origin
• Cold regions microbial ecology and biomarkers
• The development of state-of-the-art techniques and instrumentation for the analysis and detection of key organic compounds, metabolites, and microstructures in terrestrial and astromaterials.
• Carbonate globules in igneous rocks
• Mineral biomarkers from terrestrial and Martian samples
• Morphologic biomarkers and microbial ecology
• Rock varnish and microbial life