Planet-2Satellites system

Besides the basic Inertia, behavior the behavior of a Satellite treats in parallel gravitational influence of the rest of system, so that everytime it receives the event " gravity " the special listener executes CollectGRAVITY atomic action. This received information is used by Compute atomic action to calculate the next state (or a next estimation). The synchronous execution and the broadcast of events provide a particulary interesting model for many-body problem simulation.