Precision Orbit Determination

Precision Orbit Determination (POD)—GEODYN — POD, especially for orbit prediction, is critical to rapid acquisition of space objects in narrow sensor fields of view for areas such as space object custody. SGT scientists developed, maintain, and use the Orbital and Geodetic Parameter Estimation program, GEODYN, a world-class orbit determination capability and one of the two primary astrodynamics standards in use for POD by the government. GEODYN possesses the capability to estimate a set of orbital elements, station positions, measurement biases, and a set of force model parameters such that the orbital tracking data from multiple arcs of multiple satellites best fits the entire set of estimation parameters. GEODYN was the original tool of choice for the Alternate Space Control Center (ASCC) satellite catalog and is widely used by DoD, the Intelligence Community (IC), and NASA.

Satellite Laser Ranging — SGT manages the operations staff of NASA’s Goddard Geophysical and Astronomical Observatory (GGAO), supporting the International Laser Ranging Service (ILRS). The GGAO performs POD using laser ranging. This capability is routinely used to determine the precise orbital positions of spacecraft not only in Earth’s orbit but has also been used provide POD for the Lunar Reconnaissance Orbiter (LRO) spacecraft operating in the moon’s orbit.