C. Papaliolios

Extra-Solar Planetary Imager (ESPI) for Space Based Jovian Planetary Detection

The Extra-Solar Planetary Imager (ESPI) is envisioned as a space based, high dynamic range, visible imager capable of detecting Jovian like planets. Initially proposed as a NASA Midex (NASA/Medium Class Explorer) mission (PI:Gary Melnick), as a space-based 1.5 x 1.5 m2 Jacquinot apodized square aperture telescope. The combination of apodization and a square aperture telescope reduces the diffracted light from a bright central source increasing the planetary to stellar contrast over much of the telescope focal plane. As a result, observations of very faint astronomical objects next to bright sources with angular separations as small as 0.32 arcseconds become possible. This permits a sensitive search for exo-planets in reflected light. ESPI is capable of detecting a Jupiter-like planet in a relatively long-period orbit around as many as 160 to 175 stars with a signal-to-noise ratio > 5 in observations lasting maximally 100 hours per star out to ~16 parsecs. We discuss the scientific ramifications, an overview of the system design including apodizing a square aperture, signal to noise issues and the effect of wavefront errors and the scalability of ESPI with respect to NASAs Terrestrial Planet Finder mission.

ExPO: a Discovery-class apodized square aperture (ASA) extrasolar planet observatory

The Extrasolar Planet Observatory (ExPO) is envisioned as a Discovery-class space telescope for the direct detection and characterization of extra-solar planets. ExPO would also demonstrate the feasibility of a number of technologies which could be critical to the ultimate success of the Terrestrial Planet Finder mission. ExPO would detect a wide range of planet types in the visible and near IR, and do spectrophotometry and spectroscopy on many of the detected objects. The apoodized square aperture coronagraphic space telescope is designed to resolve faint companions near much brighter point-like sources by achieving very high dynamic range imaging at separations as small as 0.1 arcsec.