The NMDB begins early in the project design cycle determining the most effective orbit determination system to be used. This system may be onboard or the traditional ground-based system. The NMDB has provided orbit determination (OD) for numerous missions from precision accuracy low Earth orbit (LEO) spacecraft to lunar orbit and libration point missions.

NMDB’s GPS Enhanced Onboard Navigation System (GEONS) is an onboard Extended Kalman Filter that takes measurement data not only from GPS (a limitation of most other onboard systems) but also ground station and TDRSS 1-way data, celestial navigation measurements, and inter-spacecraft cross-link measurements. GEONS also handles multiple spacecraft simultaneously and is scalable to the level of each project. GEONS has been flight demonstrated on EO-1 and EOS-AM.

Ground orbit determination includes the routine spacecraft OD and product generation on a scheduled basis. Products generally include definitive and predictive ephemeredes, station acquisition data, shadow predicts, etc. NMDB’s ground orbit determination is normally configured in one of two ways, although other configurations are possible. One configuration is that routine orbit determination and product generation are provided by the Flight Dynamics Facility (FDF), managed by the branch. The FDF generally operates with a suite of tools including the Goddard Trajectory Determination System (GTDS) and Satellite ToolkitTM (STK) for OD and product generation respectively. The second configuration is an NMDB-designed ground system installed in the Mission Operations Center (MOC). This system may be made up of various commercial off-the-shelf software (COTS), government off-the-shelf software (GOTS) and glue-ware. This system is operated routinely by the Flight Operations Team (FOT) with training from the NMDB. NMDB would again provide navigation analysis and launch & early orbit support.

Additionally, NMDB provides further services through the FDF such as tracking data evaluation and tracking system validation.

The NMDB also invests in research into advanced navigation analysis, often in conjunction with commercial or academic partners. These analyses include formation flying, spacecraft cross-link, magnetometer navigation and GPS at high Earth orbit (HEO).