Here a solution to N-body problem-called Dynamic Universe Model (SITA) is presented; which is singularity-free, inter-body collision free and dynamically stable. The book talks about history and general introduction and why anisotropic density distributions are to be taken. The book also covers Mathematics and the final tensors formation followed by Numerical Outputs. To prove that no singularities exist in this model: Three NON-ZERO cases were shown, Angular momentum, Polar moment of Inertia, Internal Distances between all pairs of point masses. Models stability is proved by showing specific relative angular momentum is constant, “Total Energy = h=T-V” is NEGATIVE and “NONE of the masses are moving towards Center of mass”. All the related calculation results are shown. Chaotic results with the Earlier Large Astrophysical N-body Problem, errors and Exponential divergence are compared with this model. This N-body problem solution can be used by any person who has a PC for solving presently unsolved applications like Pioneer anomaly, New Horizons satellite trajectory at the Solar system level, Missing mass due to Star circular velocities and Galaxy disk formation at Galaxy level etc.