Proper elements for Earth crossing asteroids

G. F. Gronchi - A. Milani

12 May 2000

Abstract:

Proper elements for 987 known Near Earth Asteroids (NEA) have been computed using a generalized averaging principle, valid also for planet crossing orbits. This allows to assess the maximum and minimum eccentricity and inclination resulting from secular perturbations, to determine which planetary orbits can be crossed, and to find the encounter conditions, which can also be used to search for parent bodies of meteor streams. Proper frequencies for these asteroids have also been computed; then it has been possible to draw a map of the NEA's affected by the main secular resonances. This paper describes the methods used in this computation, discusses the main qualitative properties of the results, and announces the availability of the proper elements online.