A possible future NASA mission, part of the Origins Program, which would follow on from the Terrestrial Planet Finder (TPF) and produce images of Earth-like planets. To obtain a 25 x 25 pixel image of an extrasolar planet would call for an array of 5 TPF-class optical interferometers flying in formation. Each interferometer would consist of four 8-m telescopes to collect light and null it (see nulling interferometry) before passing it to a single 8-m telescope which would relay the light to a combining spacecraft. The five interferometers would be arranged in a parabola, creating a very long baseline of 6,000 km with the combining spacecraft at the focal point of the array.
