Terrestrial Planet Finder (TPF) A NASA space observatory planned for launch between 2014 and 2020. It will consist of two observatory spacecraft: one, a coronagraph, will be launched first, followed by a mid-infrared formation-flying interferometer. The observatory's mission is to survey nearby stars in a search for Earth-size planets orbiting the ‘habitable zone’ of their respective stars (the region where water might be able to exist and life night develop). The TPF will then follow up the brightest candidates it detects by subjecting them to spectroscopic analysis (e.g., to detect the chemical makeup of a possible atmosphere). In investigating atmospheric spectra, the craft may discover habitable conditions or even life itself. In addition, TPF is scheduled to conduct a program of high spatial-resolution astrophysics.