Abstract:
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It is known that most of the craters on the surface of the Moon were created by
the collision of minor bodies of the Solar System. Main Belt Asteroids, which can approach
the terrestrial planets as a consequence of different types of resonance, are actually the main
responsible for this phenomenon. Our aim is to investigate the impact distributions on the
lunar surface that low-energy dynamics can provide. As a first approximation, we exploit the
hyberbolic invariantmanifolds associated with the central invariantmanifold around the equilibrium
point L2 of the Earth–Moon system within the framework of the Circular Restricted
Three-Body Problem. Taking transit trajectories at several energy levels, we look for orbits
intersecting the surface of the Moon and we attempt to define a relationship between longitude
and latitude of arrival and lunar craters density. Then, we add the gravitational effect of
the Sun by considering the Bicircular Restricted Four-Body Problem. In the former case, as
main outcome, we observe amore relevant bombardment at the apex of the lunar surface, and
a percentage of impact which is almost constant and whose value depends on the assumed
Earth–Moon distance dEM. In the latter, it seems that the Earth–Moon and Earth–Moon–
Sun relative distances and the initial phase of the Sun θ0 play a crucial role on the impact
distribution. The leading side focusing becomes more and more evident as dEM decreases
and there seems to exist values of θ0 more favorable to produce impacts with the Moon.
Moreover, the presence of the Sun makes some trajectories to collide with the Earth. The
corresponding quantity floats between 1 and 5 percent. As further exploration, we assume an
uniform density of impact on the lunar surface, looking for the regions in the Earth–Moon |