1 Image Credit: Martin Vargic 2 PEACH: The Physiology-Exoplanet Astroecological model for Characterizing Habitability Alma Y. Ceja NASA MIRO FIELDS Fellow Planetary Research Laboratory University of California, Riverside 3 Questions: 1. What kinds of planets and stars produce habitable conditions? 2. What types of organisms could a “habitable” exoplanet sustain? 3. Which biosignatures might be observable from inhabited exoplanets? 4 Ecological Modeling Predicted Distribution Environmental Data Physiological Data 5 ROCKE-3D • Fully coupled and dynamic oceanic-atmospheric climate model • Simulates atmospheric chemistry, aerosols, the carbon cycle, and other tracers • Has been used to model Earth, Mars, Venus, TRAPPIST-1, and Proxima Centauri b Image Credit: Kaitlin Alexander and Steve Eastbrook 6 Rule-based modeling 7 Thermal Performance Curves Schulte 2014 8 The Biokinetic Spectrum of Temperature for Life on Earth • Describes maximum and minimum thermal growth rate limits for 1627 organisms • Data is inclusive of all three Domains, all six Kingdoms, and forty-three of the fifty-five phyla • Data is made available and features individual thermophysiology data Corkrey et al. 2016 9 Thermal Performance Curves 10 Fitting Performance Curves Angilletta 2006 11 Rule-based modeling organism environment remains is habitable organism ‘analyzes’ environment environment organism is not expires habitable 12 13 Biosignatures • Note: degeneracies may exist between biotic/abiotic processes which may convolute spectral signatures. 14 Next Steps: Model Validation 1. Astroecology model vetting: validate model under observed Earth environmental temperatures 2. Constraining Earth-like exoplanets: execute Earth model with variable parameters (e.g. eccentricity, obliquity, star-planet separation, stellar age) to identify limits in parameter space 3. Identifying habitable exoplanets: execute model for confirmed rocky exoplanets 15 Acknowledgements Planetary Research Laboratory [email protected] @thealmashow 16.