Direct detection of extrasolar planets and the Gemini Planet Imager

Bruce Macintosh, LLNL

Abstract:

The next frontier in the study of extrasolar planets is direct (imaging) detection of the planets themselves. With high-order adaptive optics, careful system design, and advanced coronagraphy, it is possible for an AO system on a 8-m telescope to achieve contrast levels better than 10^7, sufficient to detect warm self-luminous Jovian planets around stars as old as 1 Gyr. Such direct detection is sensitive to planets inaccessible to current radial-velocity surveys and allows spectral characterization of the planets, shedding light on planet formation and the struture of other solar systems. Our team has begun the construction of such a system for the Gemini Observatory. Dubbed the Gemini Planet Imager (GPI), this instrument will be deployed in early 2011 on the Gemini South telescope. It combines a 2000-actuator MEMS-based AO system, an apodized-pupil Lyot coronagraph, a precision infrared interferometer for calibration at the nanometer level, and a infrared integral field unit/polarimeter for detection and characterization of the target planets and circumstellar dust disks. I will present an overview of the science motivation for GPI, the instrument design and technological challenges, and predictions of the final science capability. Finally, I will briefly discuss the science possibilities for direct planet detection on the proposed Thirty Meter Telescope.