Exoplanets: Detection, Habitability, Biosignatures

An extrasolar planet, or "exoplanet", is a planet that orbits a star other than our own. To search for life beyond our Solar System, one of the first steps is finding an exoplanet that might be able to support life. Once such a planet is detected, the scientific challenge is to determine how to recognize - across the vast distances of interstellar space - whether that planet really could (or does) support life. UWAB faculty and students working in this research area are developing new techniques to search for and detect extrasolar planets, combining computer models and data from different fields to determine how planets become habitable, and examining how that habitability is maintained or lost over time. UWAB researchers also work to identify astronomical biosignatures, the global signs of life that could someday be detected on extrasolar planets.

Planetary Detection

UWAB researchers search for extrasolar planets with both ground-based and space-based telescopes, and have pioneered a new technique for finding and characterizing planets using gravitational interactions between transiting planets. These techniques are being applied to data from NASA’s Kepler mission to discover planets that are only slightly more massive than the Earth. The Spitzer Space Telescope has also been used by UWAB faculty and students to produce the first thermal infrared map of a giant exoplanet.

Habitability and Biosignatures

The UWAB community also encompasses the Virtual Planetary Laboratory (VPL) team of the NASA Astrobiology Institute. This interdisciplinary team focuses on understanding extrasolar planet habitability and biosignatures. To do this, UWAB faculty and students -- with national and international collaborators -- use a comprehensive suite of VPL computer models to simulate the formation, orbits, tides, atmospheres, and atmospheric evolution of extrasolar planets. These computer models, in combination with astronomical and planetary observations, explore the effects on habitability of radiative and gravitational interactions between a terrestrial planet, its parent star, and other planets in its planetary system. UWAB faculty and students also use computer models, laboratory measurements, and field work to explore the interplay between life and its environment, to learn how to identify biosignatures using extrasolar planetary spectra.