The development of instrumentation having utility for exopaleontological prospecting on mars

Abstract

Under development in our laboratory are miniaturized instruments for lander spacecraft suitable for exopaleontological prospecting on Mars. Miniaturized Mt~ssbauer and laser Raman spectrometers are at the focus of our research. With the Mrssbauer spectrometer we have demonstrated that iron oxides associated with bacteria found in the vicinity of submarine vents such at the East Pacific Rise, and at thermal springs in Colorado and in Yellowstone National Park, exhibit the property know as superparamagnetism. This property results from the nanophase nature of the iron oxides. Nanophase material can serve as both a potential geological biomarker and fossilizing medium provided that other characteristics occur. A mass of nanophase material could occur at an archaic thermal spring on Mars. Carbonates, in particular calcium carbonate, are also a potential fossilizing medium which is readily detected using laser Raman spectroscopy. A laser Raman spectrometer can be constructed having the size of a video cassette or smaller that functions with as little as three milliwatts of laser light. Optical fibers allow samples to be interrogated at some distance from the spectrometer by deployment to targets with robotic arms, microrobotic rovers, and even ballistic projectiles. Hydrocarbon residues can also be searched for directly or in samples processed by a technique such as capillary electrophoresis. Our philosophy is to first prospect for the kinds of mineral media having potential for being a biomarker or a fossilizing medium or for the purpose of sample selection. Once having located such a substance, other techniques such as microscopy and even sample return to Earth will be needed to determine their biological significance. The materials characterized may also help identify an environment favorable for biology, for example hydrothermal spring deposits. In addition to the previously mentioned instrumental techniques, other concepts will be discussed. This work is supported by the NASA Exobiology Program and the NASA Planetary Instrument Design and Development Program