 
Summary: Mon. Not. R. Astron. Soc. 354, 798810 (2004) doi:10.1111/j.13652966.2004.08240.x
Simulations of the population of Centaurs I. The bulk statistics
J. Horner,1,2
N. W. Evans2,3
and M. E. Bailey4
1Physikalisches Institut, Universitšat Bern, Sidlerstrasse 5, CH3012 Bern, Switzerland
2Theoretical Physics, Department of Physics, 1 Keble Rd, Oxford OX1 3NP
3Institute of Astronomy, Madingley Rd, Cambridge CB3 0HA
4Armagh Observatory, College Hill, Armagh BT61 9DG
Accepted 2004 July 19. Received 2004 July 19; in original form 2004 April 28
ABSTRACT
Largescale simulations of the Centaur population are carried out. The evolution of 23 328
particles based on the orbits of 32 wellknown Centaurs is followed for up to 3 Myr in the
forward and backward direction under the influence of the four massive planets. The objects
exhibit a rich variety of dynamical behaviour with halflives ranging from 540 kyr (1996 AR20)
to 32 Myr (2000 FZ53). The mean halflife of the entire sample of Centaurs is 2.7 Myr. The
data are analysed using a classification scheme based on the controlling planets at perihelion
and aphelion, previously given in Horner et al. Transfer probabilities are computed and show
the main dynamical pathways of the Centaur population. The total number of Centaurs with
diameters larger than 1 km is estimated as 44 300, assuming an inward flux of one new
