What is "freeflyer"

FreeFlyer is a software application for use in satellite mission analysis, design and operations. FreeFlyer's architecture centers on its native scripting language, known as FreeForm script. As a mission planning tool, it encompasses several capabilities, including precise orbit modeling, 2D and 3D visualization, sensor modeling, maneuver modeling, maneuver estimation, plotting, orbit determination, tracking data simulation, and space environment modeling.

FreeFlyer implements standard astrodynamics models such as the JGM-2, EGM-96, LP-165 gravity potential models; the Jacchia-Roberts, Harris-Priester, and NRL-MSIS atmospheric density models; the International Reference Ionosphere model; and the International Geomagnetic Reference Field magnetic field model.