Astrobiology; planetary science; using traditional and biotechnological approaches for the detection of microbial life in astrobiology and solar system exploration
B.S., Microbiology and Biochemistry, University of Central Lancashire, UK, 1992; Ph.D., Biotechnology, University of Portsmouth, UK, 1996
The main focus behind my research has been the development of scientific and measurement criteria for the unambiguous detection of life in early earth and Mars samples and future robotic and sample return missions to Mars as well as missions to Europa and Enceladus. This has evolved into a three-pronged approach of laboratory investigations using a diverse range of techniques and samples coupled with development and testing of instrumentation for future Mars missions and the characterisation of data from space flight missions to Earth orbit, Mars and Comets.
The scientific underpinning of this work has revolved around the establishment of a “null hypothesis” to life detection that relies on accurately cataloguing non-biological morphological and organic chemical input to a particular sample. My laboratory work has concentrated on samples as diverse as Apex chert, Strelley pool chert, Isua, Akilia, Gunflint samples as well as mantle xenoliths, fossil lagerstatten (Enspel, Messel) Martian meteorites, Apollo return samples, ordinary and carbonaceous chondrites, Stardust, ureilites and inclusions in diamonds. Principally I use a combination of light microscopy with high resolution scanning confocal Raman spectroscopy to initially survey samples of interest. The search for life cannot be accomplished with confidence in one particular measurement and as such multiple analysis techniques must be used on the same sample to give a convincing answer. Due to this I have developed the capability to use and interpret data from a wide range of instrumental techniques including; Atomic Force Microscopy, Scanning and Transmission Electron Microscopy, FTIR spectroscopy, Isotope Ratio Mass Spectroscopy, Time of Flight Secondary Ion Mass Spectrometry, Gas Chromatography Mass Spectrometry, Electron and Ion Microprobes, X-ray elemental and Diffraction analysis (EDX and XRD), microbial culturing and aseptic technique, biomolecule extraction, DNA amplification, Lab-on-a-chip microfluidic capillary electrophoresis and metabolism and endotoxin analysis. I have been instrumental in developing several of the latter techniques for robust use in field conditions and was a part of a team using non-culture based methods on the International Space Station.
My laboratory work with a range of co-investigators has led to some significant discoveries including; lunar graphite, new carbon allotropes in meteorites, the detection of 4 abiogenic organic carbon synthesis mechanism on Mars, as well as water in lunar and Martian rocks. This year I have also been part of the COSAC instrument team onboard the Philae lander on the ESA Rosetta mission. By following the trail of abiotic carbon I have also become very interested in the terrestrial and Martian deep carbon cycles. My current work is focussing on what appears to be an explanation for reduced carbon species within the terrestrial and Martian mantles, following the unambiguous discovery of organic carbon in Martian meteorites.
Currently I am also a co-investigator on the Sample Analysis at Mars (SAM) instrument onboard the Curiosity. My duties have been to rapidly assess data products and help in the development of science plans to undertake the search for organic material on Mars. These studies will continue and extend my current mission involvement in the Curiosity and Rosetta missions to the Mars 2020 mission as a co-investigator on the SHELOC instrument and hopefully after samples return from Mars.
My future goals are to continue to address the problems of early and extraterrestrial life detection using all the tools at my disposal. I will to continue to augment the techniques I have with new cutting edge technologies, including instrument concepts that I have been developing. I would in the near future like to integrate high resolution electron imaging, Confocal Raman spectroscopy and augment that with Time of Flight SIMS instrument capable of in-situ organic compound characterisation and preparation. This instrument initially funded for a short feasibility study by the DCO has become a commercial reality and this kind of cutting edge technology would address many of my own and my colleagues science problems.
Furthermore, in an effort to continue setting an abiotic baseline for the detection of life myself and collaborators have been undertaking high pressure and temperature experiments into organic carbon production during the cooling of silicate melts. I am currently funded to undertake these experiments through a NASA grant and we will continue to vary temperature, composition and oxygen fugacity parameters to characterise possible organic synthesis reactions in these systems.
Finally, I am also exploring a further line of research that I have recently begun, to probe the reactions that could lead to the transition of abiotic chemistry to prebiotic chemistry and then life. At this time this work has involved bioinformatics research into the nature of protein nucleic acid interactions that could have led to the first proto-life molecular constructs that led to information exchange and storage under the conditions that formed life on earth. It is my goal to transport this in-silico work into a number of laboratory experiments that would shed light on the origin of protein / nucleic acid interactions.