Originally created to solve problems involving Earth-orbiting, it is now used in the and and for many other applications. STK has been developed since 1989 as a commercial off the shelf software tool. At the core of STK is a geometry engine for determining the time-dynamic position and attitude of objects ('assets'), and the spatial relationships among the objects under consideration including their relationships or accesses given a number of complex, simultaneous constraining conditions. 11.1 / June 2016 2 years ago ( 2016-06) Website Systems Tool Kit (formerly Satellite Tool Kit), often referred to by its initials STK, is a physics-based package from that allows engineers and scientists to perform complex analyses of ground, sea, air, and space assets, and share results in one integrated solution.