  The source of impactors capable of producing the cratering asymmetry on
Triton is open to debate. While hyperbolic comets are the likely source of
impactors, the theoretically predicted crater distribution due to impacts from
comets is incompatible with the observed crater distribution on Triton. In this
study, we adopted a dynamical approach to investigate the crater distribution
produced by three sources of impactors: Neptune-centric impactors on prograde,
low-inclination orbits, Neptune-centric impactors on high-inclination orbits
such as its irregular satellites, and heliocentric impactors with hyperbolic
orbits. We employ N-body simulations which take into account the dynamics of
the impacts. We found that none of the impactor sources alone are able to
reconcile with the crater distribution on Triton. The crater distribution
produced by a low-inclination Neptune-centric source is narrowly concentrated
on Triton's leading hemisphere whereas the heliocentric impactors produce too
many craters on the trailing hemisphere compared to the observed crater
distribution. All three impactor populations produce craters on the trailing
hemisphere of Triton. We derived the impact distribution of a mixed population
of impactors using a Monte Carlo approach and found that if the population
consists of mainly heliocentric impactors (70%), the resulting impact
distribution fits the observed crater distribution on Triton's leading
hemisphere well.
