Elisa Dong is a final year PhD candidate at York University researching planetary atmospheres trying to understand how and why things move from point A to point B, or don’t. Her favourite research question is, "what if?". She completed her BSc in Geophysics at the University of Waterloo, and an MSc at Western University. Outside of work, Elisa is usually found tending to hundreds of houseplants or playing tabletop RPGs.
Title: The Mystery of Martian Methane and A Potential Solution
Abstract: The search for methane on Mars has spanned over two decades. More recently, instruments developed with the intent of measure methane onboard the Curiosity Rover and Trace Gas Orbiter suggest that there is both methane near the surface, yet none higher in the atmosphere. The apparent discrepancy between measurements and has led to intensive discussion in the literature surrounding the origins and sequestration of methane on Mars, and debate over robustness of the measured values.
While it is exciting to speculate that microbial life could be the reason for such variability, an active methane destruction mechanism could also explain the observations. However, commonly considered methane destruction mechanisms such as photolysis and oxidation remove methane on the order of hundreds of years. This is inconsistent with the timescale of global atmospheric mixing. Zhang et al. (2022), suggested methane can be destroyed on the order of hours to days when adsorbed onto UV-activated perchlorate in their simplified atmospheric model. In this talk, I investigate the implementation of their fast methane destruction mechanism using a more realistic atmospheric model, and evaluate whether this mechanism is sufficient to resolve the methane problem. I will also go over some of the key mistakes and assumptions that were surprisingly difficult to catch. I’ll conclude with a perspective on applications of this work and, hopefully, some inspiration for both exoplanetary and Earth based research moving forwards.