Asteroid 433 Eros: The Target Body of the NEAR Mission

Asteroid 433 Eros was the first near-Earth asteroid to be discovered and nearly 100 years of ground-based observations have aIlowed a rough physical characterization of the body. Eros is a S-type asteroid whose dimensions are approximately 40.5x 14.5 x 14.1 km. Its rotation is in a direct sense with a period of 5.27 hours and its geometric albedo is 0.17. Good observing opportunities in late 1995 and several months in 1998 will allow these physical parameters to be further refined. At the time of the NEAR spacecraft arrival in early 1999, the Eros ephemeris uncertainties will be less than 50 km based on ground-based astrometric observations alone.