  The far-reaching gravitational force is described by a heuristic impact model
with hypothetical massless entities propagating at the speed of light in vacuum
and transferring momentum and energy be- tween massive bodies through
interactions on a local basis. In the original publication (Wilhelm et al.
2013), a spherical symmetric emission of secondary entities had been
postulated. The potential energy problems in gravitationally and
electrostatically bound two-body systems have been studied in the framework of
this im- pact model of gravity and of a proposed impact model of the
electrostatic force (Wilhelm et al. 2014). These studies have indicated that an
anti-parallel emission of a secondary entity - now called graviton - with
respect to the incoming one is more appropriate. This article is based on the
latter choice and presents the modifications resulting from this change. The
model has been applied to multiple interactions of gravitons in large mass
conglomerations in several publications. They will be summarized here taking
the modified interaction process into account. In addition, the speed of
photons as a function of the gravitational potential are considered in this
context together with the dependence of atomic clocks and the redshift on the
gravitational potential.
