Paper: astro-ph/0505235
Date: Wed, 11 May 2005 21:15:15 GMT (60kb)

Title: Constraints on the Orbital Evolution of Triton

Authors: Matija Cuk, Brett J. Gladman
Comments: 10 pages, 4 figures, accepted for ApJL
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We present simulations of Triton's post-capture orbit that confirm the
importance of Kozai-type oscillations in its orbital elements. In the context
of the tidal orbital evolution model, these variations require average
pericenter distances much higher than previously published, and the timescale
for the tidal orbital evolution of Triton becomes longer than the age of the
Solar System. Recently-discovered irregular satellites present a new constraint
on Triton's orbital history. Our numerical integrations of test particles
indicate a timescale for Triton's orbital evolution to be less than $10^5$ yrs
for a reasonable number of distant satellites to survive Triton's passage. This
timescale is inconsistent with the exclusively tidal evolution (time scale of
$>10^8$ yrs), but consistent with the interestion with the debris from
satellite-satellite collisions. Any major regular satellites will quickly
collide among themselves after being perturbed by Triton, and the resulting
debris disk would eventually be swept up by Triton; given that the total mass
of the Uranian satellite system is 40% of that of Triton, large scale evolution
is possible. This scenario could have followed either collisional or the
recently-discussed three-body-interaction-based capture.

\\ ( http://arXiv.org/abs/astro-ph/0505235 , 60kb)