In support of the goals and objectives of NASAs Science Mission Directorate, the proposed research will: 1) investigate processes of biosignature capture and preservation in modern siliceous hydrothermal deposits over a range of physical, chemical and biological conditions; 2) characterize ancient siliceous hydrothermal deposits to better understand how post-depositional changes (diagenesis, including silica phase changes and cementation) affect microtexture, composition and biosignature retention; and 3) identify the data sets needed to definitively identify such deposits on Mars during future in-situ robotic missions. These goals will be supported by achieving the following research objectives: 1) development of a framework for assessing potential habitability and life on Mars by exploring for aqueous minerals and detecting organic materials; 2) investigate processes of biosignature capture and preservation and characterize samples from a suite of modern and ancient (modern through Devonianaged) silica hot spring deposits over a range of physical and chemical conditions (alkaline to acidic, 15-75 degrees C, high to low iron); 3) use biosignature and fabric information from modern springs to characterize ancient deposits and to assess whether these ancient deposits were deposited from acidic or alkaline springs; and 4) use a suite of well-characterized hydrothermal samples to assess the utility of the JPL-designed Multispectral Microscopic Imager (MMI) and Mars Microbeam Raman Spectrometer (MMRS) instruments as astrobiological payload elements. A suite of high resolution laboratory methods (light/polarizing and fluorescence microscopy, Xray powder diffraction (XRPD), scanning electron microscopy (SEM), inductively-coupled plasma mass spectrometry (ICP-MS) and gas chromatography mass spectrometry (GM-MS)) in laboratories at Arizona State University (ASU) will be used to characterize the microtexture, mineralogy, micropaleontology, paragenesis, elemental and organic composition, and evaluate the effects of diagenesis (post-depositional changes in texture and composition and effects on biosignature retention) of modern and ancient silica sinters from Yellowstone National Park (WY), the McGinnis Hills (NV), Steamboat Springs (NV), the central highlands Iceland, the Coromandel Peninsula (New Zealand), and the Devonian Drummond Basin (NE Australia). The results of these detailed laboratory investigations will be used to investigate processes of biosignature capture and preservation, characterize past hydrothermal environments and their diagenetic histories, and create a well characterized suite of samples that can be used as ground truth for testing the Multispectral Microscopic Imager (MMI) and the Mars Microbeam Raman Spectrometer (MMRS) instruments being developed by JPL for future flight missions. The two flight instruments will be used to assess microscale habitability in samples and to look for fossil microbial biosignatures over a broad range of hydrothermal conditions. The study will focus on mid-temperature, channel, and distal apron (low-temperature) environments, where microbial biofabrics and organic biosignatures have been shown in previous studies by the PI to be well preserved (1). This research will lead to an improved understanding of microbial fossilization processes and biosignature retention needed to advance the development of flight instrumentation that might be included in the first life detection payload, which is likely to be launched to Mars sometime after the middle of the next decade.
|Effective start/end date||9/1/08 → 2/28/12|
- NASA: Goddard Space Flight Center: $90,000.00