Question: What do the University of Kentucky, George Washington University, NASA’s  Jet Propulsion Laboratory and the University of Wisconsin have in common?

Answer: These institutions are partners in a consortium funded by NASA’s Astrobiology institute (http://www.geology.wisc.edu/~astrobio/) that is exploring the origin of life on Earth and the possibilities for life on Mars and elsewhere in our solar system.

NASA’s  Astrobiology Institute (NAI) was established in 1998 to foster studies of the origin, evolution, distribution and future of life on Earth and in the Universe (see http://astrobiology.nasa.gov/nai/about/).  This includes how planetary processes give rise to life, how they sustain or inhibit life, and how life can emerge as an important planetary process; how astrophysical processes give rise to planets elsewhere, what the actual distribution of planets is, and whether there are habitable planets outside of our solar system; a determination of whether life exists elsewhere and how to search for and identify it; what the ultimate environmental limits of life are, whether Earth’s biota represent only a subset of the full diversity of life, and the future of Earth’s biota in space.

Chris Romanek, a faculty member in the Department of Earth and Environmental Sciences at UK and a co-investigator on the project, has been studying surface processes and the potential for microbial life on Mars for over twenty years. “Our work on the geochemistry of the martian surface extends back to the early 1990s when I was a post doc at NASA’s Johnson Space Center. At that time, NASA’s exobiology program supported this line of research and astrobiology wasn’t part of the agency’s portfolio.” But with the recognition that microorganisms inhabit  every nook and cranny of earth’s surface, from hydrothermal deep sea vents to African gold mines (> 100°C) to the sea ice and permafrost of the polar regions (<0°C), anywhere liquid water is found, the potential for life elsewhere in the solar system is not so far-fetched.

Romanek, a "top ten" researcher in the field of Mars science for the years 1994 to 2004 (http://www.esi-topics.com/mars/index.html), was one of the first scientists to study the now controversial ALH84001 Martian Meteorite. His original contribution in the journal Nature on the formation temperature of unusual carbonate mineral assemblages in the ALH meteorite, and his follow up paper in Science magazine that proposed a biological origin for these features sparked an international debate on the geological evidence required to verify a biological origin for extraterrestrial materials. Interest in this topic, both from the scientific community and the public, resulted in new funding opportunities, including NASA’s Ancient Martian Meteorite Program and the Astrobiology Institute.

Romanek’s NAI research, which focuses on identifying and developing “biosignatures” for detecting life in the earliest part of Earth's history or on other planetary bodies, supports one post doctoral associate and numerous graduate students at UK as well as visiting scholars from Spain, France, and Turkey. The UK research team is presently investigating geochemical signatures that provide insights into the environments of formation and origin of carbonate minerals that form at temperatures conducive to life. Carbonate minerals are being synthesized in the laboratory under tightly controlled conditions so that inorganic geochemical fingerprints can be distinguished from processes that require organic molecules, including those that may be produced biochemically by living microorganisms. “Once we have the ability to recognize the geochemical and isotopic fingerprints of life in the rock record, we can use this tool to interrogate earth’s oldest sedimentary record and sedimentary rocks that exist on other planetary bodies. Mars presents the perfect opportunity to probe our earliest record of processes that involved liquid water in our solar system because of the lack of plate tectonics. Unfortunately, plate tectonics has consumed or severely altered our earliest record of sedimentary processes on Earth. If life ever did evolve on the red planet, a geochemical signature of life is undoubtedly preserved in rocks and minerals and we have to be ready to decipher it.”

With our present suite of orbiting spacecraft and rovers and the recent launch of the Mars Science Laboratory (MSL) in November, scientists have the opportunity to understand the sedimentary rock record on Mars with unprecedented resolving power and sophistication.  “Our group hopes that upcoming satellite and rover discoveries will benefit from the work we are doing now in the laboratory through our NAI collaborations.”

Although Romanek’s initial NAI grant is drawing to a close, the consortium is actively engaged in preparing their next multi-million dollar proposal to extend their project for another five years. UK participants in the renewal include Romanek, post doc Chakraborty and a cadre of undergraduate and graduate students from EES as well as faculty from the Department of Chemistry (Marcel Guzman), and additional collaborators from UCLA and Montana State University. It has been an exciting journey from the laboratory to the surface of Mars and back, and it is one that Romanek hopes to continue well into the future at the University of Kentucky.