nasa 4dThis allows any Web application to offer an interactive 4D display of the trajectories of satellites known to SSC. The available Web Services are: Launch the 4D Orbit Viewer (assuming JavaNASACR–2011-217051 4D Dynamic Required Navation Performance Final Report Daniel M. Finkelsztein and James L. Sturdy Raytheon Company, Hampton, Virginia Omeed Alaverdi