From UW News:
Scientists have discovered thousands of exoplanets, including dozens of terrestrial — or rocky — worlds in the habitable zones around their parent stars. A promising approach to search for signs of life on these worlds is to probe exoplanet atmospheres for “biosignatures” — quirks in chemical composition that are telltale signs of life. For example, thanks to photosynthesis, our atmosphere is nearly 21% oxygen, a much higher level than expected given Earth’s composition, orbit and parent star.
Finding biosignatures is no straightforward task. Scientists use data about how exoplanet atmospheres interact with light from their parent star to learn about their atmospheres. But the information, or spectra, that they can gather using today’s ground- and space-based telescopes is too limited to measure atmospheres directly or detect biosignatures.
Exoplanet researchers such as Victoria Meadows, a professor of astronomy at the University of Washington, are focused on what forthcoming observatories, like the James Webb Space Telescope, or JWST, could measure in exoplanet atmospheres. On Feb. 15 at the American Association for the Advancement of Science’s annual meeting in Seattle, Meadows, a principal investigator of the UW’s Virtual Planetary Laboratory, will deliver a talk to summarize what kind of data these new observatories can collect and what they can reveal about the atmospheres of terrestrial, Earth-like exoplanets. Meadows sat down with UW News to discuss the promise of these new missions to help us view exoplanets in a new light.