| Exoplanet Atmospheres and the Search for Signs of Life Beyond Earth |
| Sara Seager, Massachusetts Institute of Technology |
| Event Type: Special Seminar |
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| Time: 11:00 AM - 12:30 PM |
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| Location: Speaker: Zoom; Audience: 940 or Zoom |
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| Abstract: Thousands of exoplanets are known to orbit nearby stars and small rocky planets are established to be common. The ambitious and lofty goal of identifying a habitable or inhabited exoplanet is within reach—by the new James Webb Space Telescope’s (JWST) capability for observations of exoplanet atmospheres for water vapor and gases that might be attributed to life. The JWST uses transmission spectroscopy, a technique that relies on disentangling the host star and planet signals, and for atmospheres of rocky planets orbiting in the habitable zone of their host stars is limited to small red dwarf host stars. Yet now that we are faced with the unprecedented quality of JWST data, the community faces two major challenges. The first is that low-level host star variability caused by stellar surface inhomogeneity from magnetic fields can dominate the exoplanet atmosphere signal. The second challenge comes from significant inconsistencies when applying intricate inverse-problem algorithms to retrieve atmospheric parameters from data. Can we overcome these challenges or will the identification of a habitable or inhabited exoplanet have to wait for the next generation of “direct imaging” space-based telescopes. Link to the Event Video |