The recovery of near-Earth asteroids

A very important step for the acquisition of accurate orbital information o f near Earth asteroids (NEAs) is the recovery process. About one-third of t he known NEAs have been observed for more than one opposition. We studied t he circumstances of the recovery of all NEAs with atleast two oppositions a nd found that there are several ways to find observations of a different op position from that of the discovery. We divided all the recoveries into fou r different classes. Following the observations at the new opposition, we c oncluded that planning observations at the telescope is still the best way to hope to observe NEAs at a new opposition. At the same time we reached th e conclusion that a large number of NEA observations are still to be found in existing archival astronomical records. (C) 2000 Elsevier Science Ltd. A ll rights reserved.