Colloquium

Speaker:  Jared Males, Steward Observatory, Univ of Arizona

Title:   Characterization of Solar-System-Like Planets Using Direct Imaging with the Giant Magellan Telescope

Abstract:  Over the last 30 years we have witnessed a scientific revolution: the discovery of extrasolar planets in large numbers.  With nearly 6000 confirmed exoplanets, and over 7000 candidates being vetted, we now know that planets are a ubiquitous product of star formation.  However, the study of exoplanets remains a data-starved field.  The vast majority of these discoveries were made with indirect techniques (radial velocity and transits), which give us only a minimum mass and/or radius but no information about their atmospheres.  Bluntly put, we know almost nothing about these planets.  The few that have been spectroscopically characterized, whether by transit spectroscopy or direct imaging, are not generally typical of the population of known exoplanets or the planets in our Solar System.  The technology of direct imaging is on the cusp of improving this situation by enabling characterization of temperate exoplanets in reflected starlight.  Current 6.5-10 m telescopes may be able to do so for a small number of nearby targets, including Proxima b.  The real breakthrough will come with the completion of the 25-39 m Extremely Large Telescopes (ELTs). Achieving this goal will require extreme adaptive optics (ExAO) system with coronagraphs performing near the fundamental limits imposed by atmospheric turbulence, dynamic instrumental aberrations, and photon noise.  If this performance level can be reached, our detailed modeling of the known nearby planets shows that hundreds of exoplanets will be characterized from ELTs in both hemispheres.   Here I will describe our progress towards demonstrating this performance with MagAO-X, a 2000 actuator ExAO system on the Magellan Clay 6.5 m telescope, and our potential for initial characterization of the nearest terrestrial exoplanet.  I will then describe our plans for GMagAO-X, a 21,000 actuator system for the 25 m GMT and its many exciting high spatial and spectral resolution science cases.