While the role of late diagenesis alteration and preservation of biomarkers (e.g., lipids) is well understood, far fewer studies have focused on the diversity of early diagenetic processes which dictate preservation depending on environmental parameters. In order to better understand the relationship between depositional environment (e.g., local geochemistry) and sedimentary biological processes, here we are analyzing a suite of thermally immature fish concretions (Mallotus villosus) from various locations around the world via lipid extraction which have partially decomposed and contain a wide range of lipids from eukaryotes, bacteria and archaea.
These fossils provide a unique opportunity to probe the diagenetic continuum or the "window" into the biological-geological (e.g., sterols to steranes; hopanols to hopanes) transition and preservation of biomarkers
In Search for the RNA World on Mars
Major strides in understanding the origin of life support the notion that life on Mars, if it ever existed, may have shared a common genesis with life on Earth. Namely, analogous pre-biotic environments, molecular feedstocks (including cometary sources), and plausible abiotic reactive pathways predicted on Earth and applicable on Mars may have resulted in parallel origin events in accordance to the RNA-world hypothesis. This notion suggests that past or present Martian life may have utilized known building blocks (e.g., nucleic acids, sugars, amino acids) and closely resembled life as we know it.
Assuming that viable nucleotides were being delivered to Mars via unspecified sources (e.g., cometary sources or via in-situ synthesis), we are investigating whether the early Martian environment was permissive towards the accumulation, stability, and polymerization of long-lived pre-biotic RNA oligomers that could have eventually precipitated life.
The Search for Extra-Terrestrial Genomes
Life on Mars, if it exists, may share a common ancestry with life on Earth due to lithological exchange (presumably containing microbial life) between early Mars and Earth. Therefore, environmental DNA (and RNA) metagenomic sequencing has the potential to provide unambiguous evidence of ancestrally-related life on Mars. The Search for Extraterrestrial Genomes (SETG) instrument integrates nucleic acid extraction and nanopore sequencing for in-situ life detection on Mars.
Carr et al. (2017) Aerospace Conference, IEEE ResearchGate
Mars Human Landing Site Study
In late October of 2015 NASA held the first workshop to identify and discuss candidate locations where humans could land, live, and work on the martian surface.
Site 36: Coprates Chasma, Valles Marineris
Our proposed exploration zone in the western aspect of Coprates Chasma, 293.367°E - 11.684°N, contains several regions of scientific and engineering interest including: recurring slope lineae (RSL), cross cutting alluvial fan deposits, tilted Noachian blocks, impact craters, olivine deposits, clay mineral deposits and exposed deep crustal lithologies. Favorable environmental conditions include strong year-round solar insolation and high atmospheric pressures. [Photo by NASA HQ]