Place: 4421 Sterling Hall, Coffee and cookies 3:30 PM. Talk begins at 3:45 PM
Speaker: Tristan L’Ecuyer, UW Atmospheric and Oceanic Sciences
Abstract: Recent advances in satellite-based astrophysics-focused telescopes have begun an exciting new era of exoplanet exploration in which it may soon be possible to directly image exoplanets orbiting the sun’s nearest neighbors. The spectroscopic surveys enabled by such technology offer the potential to move beyond detecting and inferring the mass and orbital characteristics of exoplanets to characterize their atmospheric and surface characteristics and, ask whether some may feature the building blocks required to support life. Considerable development is, however, required before direct imaging algorithms are sufficiently mature to make optimal use of such technology. But NASA has also been collecting detailed observations of Earth since the pioneering work of some University of Wisconsin professors in the 1950’s. The subsequent five decades of satellite-based Earth observations offers an under-tapped wealth of information to guide the development of new algorithms to identify water, ice, cloud, and vegetation signatures in direct imagery of exoplanets. This presentation will introduce a subset of modern Earth observations that are particularly relevant to this problem in the context of the Earth science applications they address. Progress toward incorporating this knowledge into a new framework for searching for Earth-like spectral signatures in direct exoplanet imagery will be described. Preliminary examples demonstrate the utility of the resulting `Earth simulator’ to characterize the spectral signatures of Earth-like planets and establish the optimal band passes, spectral resolution, and minimum signal-to-noise ratio of proposed observing systems for identifying key features in these spectra. These initial results will be placed in the broader context of the rapidly evolving, emerging exoplanet imaging field.