People: Astrobiology Postdocs

Shawn Domagal-Goldman
Astronomy

My primary work at the University of Washington focuses on terrestrial planetary atmospheres and their interactions with the biota, oceans, and sediments below them. The atmosphere interacts with a planet's hydrosphere, lithosphere, biosphere, and cryosphere, while acting as a primary control on the climatological and spectral properties of the planet. Thus, the atmosphere is a major component of important feedback cycles, and atmospheric science plays a crucial role in both Earth systems science and astrobiology. My primary goal is to develop self-consistent explanations for the data from the rock records of the early Earth and Mars while expanding our ability to use spectral data from planets to uncover details about their surfaces.

The main tools I use in my research are models of planetary atmospheres. Our photochemical models can predict altitude-profiles of gas concentrations, given biological and volcanic outgassing rates. We then take these profiles, as inputs to climate models that can predict the temperature at the surface of the planet, the temperature structure of the atmosphere, and the spectrum produced by the planet. We can also tie these predictions back into the photochemical code via a energy balance model that can predict (amongst other things) the vigorousness of the hydrological cycle on the planet. We are also beginning work on using quantum-mechanics codes to predict the rate constants of reactions that will be important in exoplanet atmospheres but that are relatively unimportant in the modern Earth's atmosphere. Together, these different models answer questions on spatial scales from Angstroms to astronomical units, and operate on timescales from nanoseconds to gigayears. The boundary conditions for our models require input from biologists, chemists, astronomers, geologists, and physicists, making our research fundamentally interdisciplinary.