In 2003 NASA commissioned a Science Definition Team (SDT) (Stokes, et al., 2003) to study the threats posed by Near-Earth Objects (NEOs), recommend efficient methods for detecting NEOs down to 140 meters in diameter, and suggest conceptual mitigation techniques. In this same time frame, Congress set the goal of cataloguing 90% of all NEOs down to 140 meters diameter by 2020. The SDT concluded that the infrared passband from ~5 to ~11 microns is the best for finding NEOs; that an aperture of 50

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... entimeters is sufficient; and that locating a NEO-finding observatory in a Venus-like orbit is ideal. Since then, NASA and its industrial partners (such as Ball Aerospace) have flown two very NEO-relevant deep-space missions-the Spitzer Space Telescope and Kepler. Herein, a high-reliability, credibly-costed design is presented based on Spitzer and Kepler that meets the 90%/140-m/2020 requirements for about $600M. This design will also detect about 85% of all >100 meter NEOs, about 70% of all >65 meter NEOs, and about 50% of all >50 meter NEOs. These smaller NEOs constitute a newly recognized threat regime that cannot be efficiently found from the ground. George E. Brown Bill, PDC in Grenada, Spain. PACS: 96.30.Ys, 96.25.De, 95.85.Hp, 95.75.Rs, 95.55.Pe, 95.55.Fw