ACCESS: a concept study for the direct imaging and spectroscopy of exoplanetary systems

Abstract

ACCESS is one of four medium-class mission concepts selected for studyin 2008-9 by NASA's Astrophysics Strategic Mission Concepts Studyprogram. ACCESS evaluates a space observatory designed for extremehigh-contrast imaging and spectroscopy of exoplanetary systems. Anactively-corrected coronagraph is used to suppress the glare ofdiffracted and scattered starlight to contrast levels required forexoplanet imaging. The ACCESS study considered the relative merits andreadiness of four major coronagraph types, and modeled their performancewith a NASA medium-class space telescope. The ACCESS study asks: What isthe most capable medium-class coronagraphic mission that is possiblewith telescope, instrument, and spacecraft technologies available today?Using demonstrated high-TRL technologies, the ACCESS science programsurveys the nearest 120+ AFGK stars for exoplanet systems, and surveysthe majority of those for exozodiacal dust to the level of 1 zodi at 3AU. Coronagraph technology developments in the coming year are expectedto further enhance the science reach of the ACCESS mission concept.