Colloquium by Jacob Haqq-Misra, Blue Marble Space
Earth is the only planet in the solar system with habitable surface conditions. Life on Earth also modifies the global environment, with an atmospheric composition that includes contributions from biological as well as technological sources. Some of these global-scale influences of life could be observed remotely, manifesting as potential “biosignatures” or “technosignatures” that could be detectable across astronomical distances. This suggests the possibility of searching for exoplanets within the “habitable zone” of their host star, where liquid water could persist, and then further examining promising candidates for biosignatures or technosignatures. Exoplanet climate model calculations provide important guidance for selecting which planets to search, while observations of exoplanets are also showing promise for constraining the assumptions within such models.
In this presentation, I will discuss this interplay between exoplanet modeling and observations with a focus on Earth-sized planets in synchronous rotation around low mass stars. I highlight results from climate modeling studies of the planet TRAPPIST-1 e that can help to guide and interpret observations. Searching for long-duration biosignatures or technosignatures inevitably involves extrapolations from Earth, with data-driven narratives available for the past but much deeper uncertainties about the future. I also present projections of Earth’s future technosphere, which can serve as analogs for extraterrestrial technospheres and help to define technosignature search strategies. I discuss prospects for continuing the characterization of terrestrial exoplanets, and the search for biosignatures and technosignatures, with future mission concepts.
Cookies will be available, starting at 3:45.
Host: David Kipping