The New Worlds Observer (NWO) mission uses a large external occulter, or "starshade," to block the light from
nearby stars and cast a deep shadow over the entrance aperture of a space telescope, enabling it to detect and characterize
Exo-Solar Planets. Since these planets are intrinsically faint (30th to 32nd magnitude), the telescope must have a large
aperture (2.4 to 4 meters) and the starshade must be large enough (25 to 50 meters) to create a shadow that is deep
enough (108 to 1010 starlight suppression) and large enough (5 to 10 meters in diameter) to envelop the telescope. The
telescope must also be far enough from the starshade (30,000 to 80,000 kilometers) that planets close to the star (50 to 65
milli-arc-seconds) are not occulted. Since the starshade's performance is inversely proportional to the wavelength of the
starlight, the telescope must operate in the visible and near infrared. The telescope should also have a significant capability
for general astrophysics observations, since it will have more than half its time available for other observations while
the starshade is moving from one target to the next.
This paper describes our conceptual design for the NWO telescope, including its instrument suite and operations concept.
We note that in addition to comparative planetology studies and the detection and characterization of terrestrial
planets, the telescope could provide a UV/Optical observing capability for the general astronomical community in the