Earth-size Exoplanets

Thu, Feb 26, 2015 at 4:00 pm

1 LeConte Hall

Andrew Howard (IfA)

 Earth-size exoplanets and their slightly larger ‘super-Earth’ cousins are the most abundant planets orbiting close to Sun-like stars. These planets have diverse physical compositions, unusual atmospheres, and poorly understood origins. My talk will trace the discovery and early characterization of these small worlds through Doppler surveys, the Kepler mission, and atmospheric transmission spectroscopy. Recent highlights from my group include the first measurement of a terrestrial density for an Earth-size exoplanet, a measurement of the prevalence of Earth-size planets in the Habitable Zone, and observations showing that most planets larger than about 1.5 times Earth size are gas dominated while those smaller are mostly rocky. Looking forward, I will describe my group’s discovery and characterization of planets with the K2 mission, our search for nearby planets approaching an Earth mass with the APF Telescope, and a future Earth-hunting spectrometer for Keck Observatory called SHREK.