A spacecraft’s trajectory starts with its launch. Although the trajectory of the launcher is not calculated by a space systems engineer, the trajectory in which the spacecraft is put by the launcher is of extreme importance. Not only is it the starting point for the trajectory design, it also determines the spacecraft mass which makes the launcher selection a critical decision during any spacecraft design.
Biesbroek, R. (2016). Lunar and Interplanetary Trajectories. Lunar and Interplanetary Trajectories. Springer International Publishing. https://doi.org/10.1007/978-3-319-26983-2