Abstract: 
How unique is the Earth? Are we alone in the Universe? These questions have shaped our cultural norms for millennia and will continue to do so as we find clues to addressing them. Our answer to those questions is based on the study of planetary processes taking place in specific bodies of our solar system, for which we have the most data. However, such an approach leads to the risk of tailoring our understanding to a few individual examples, while missing generalizations.

In this seminar, I present an attempt at linking traditional Earth and planetary sciences to the exoplanetary field of astrophysics. The core idea is to test our understanding of abiotic processes occurring on rocky planets in our solar system by using statistical predictions of atmospheric spectra. To that end, we develop a model of rocky planet evolution including the transport of chemical compounds between different interior and surface reservoirs, that can be constrained by observations available for Earth, Venus and Mars.

Variation of model parameters around those relevant to the bodies of our solar system should allow us to get a sense of the accessible diversity of atmospheres given our current understanding of abiotic processes. Differences between that distribution and future observation will help us (1) target areas requiring a deeper understanding of processes (i.e., processes we may have overfit to available data), but also (2) highlight planets which atmosphere cannot be obtained using abiotic processes only.

Speaker: Dr. Matthieu Laneuville, Earth-Life Science Institute (ELSI).

Speaker bio: 
Matthieu Laneuville is a project associate professor at the Earth-Life Science Institute (ELSI) in Tokyo, Japan. He obtained his PhD degree in Geophysics from the Institut de Physique du Globe de Paris (IPGP), working with M. Wieczorek and D. Breuer on the long term evolution of Earth's Moon.

Host: Tony Z. Jia, ELSI

Date: Fri, 7 August at 15:30 JST (Fri, 7 August 2020 at 06:30 UTC)

Venue: Online