The Arcetri NEO Precovery Program

The Arcetri Near Earth Object Precovery Program (ANEOPP) is a project dedic ated to the identification of images of Near Earth Objects (NEOs) on past a rchival materials, an activity usually referred to as precovery. Going year s back in time to locate such images results in the acquisition of very goo d orbital information, which, in turn, allows astronomers to perform more a ccurate studies of the dynamical evolution and physical characterization of NEOs, as well as improve assessments of their impact hazard. We discuss th e tasks involved in this work and the basic techniques used to yield succes sful identifications on photographic plates. Begun in mid-1999, ANEOPP has precovered more than 70 NEOs to date, which were previously observed only d uring the discovery apparition. The keys to obtaining these results have be en: i) easy access to competitive collections both in digital form and as p lastic copies; ii) traveling to additional collections; iii) the recent dev elopment of reliable algorithms to determine the boundaries of the recovery region, which is the portion of the celestial sphere where an asteroid wit h an uncertain orbit can be found at a given time.