Abstract: An orbital trajectory planning system includes a first computer processor environment configured to preprocess data for providing to a physics-based n-body simulation model, the first computer processor environment including a graphical user interface (GUI) for receiving input from a user. The system also includes a second computer processor environment running at least partially trained neural network software that has been trained to perform nonlinear mapping of the output of the n-body simulation model to a result related to a proposed trajectory for a spacecraft, the second computer processor environment receiving input information from the first computer processor environment. Further the system relates to a third computer processor environment configured to receive data related to the output from the neural network of the second computer processor environment, the third computer processor environment providing user useable output through a GUI running on the third computer processor environment.