I was thinking about how we can predict the location of planets with a high degree of accuracy. They are pretty close to an ideal physical system and is governe

I was thinking about how we can predict the location of planets with a high degree of accuracy. They are pretty close to an ideal physical system and is governed by a single physical law. The dynamics are so well understood that we have been able to predict the existence of, and find, other planets based on small deviations. We have even been able to refine our understanding of the structure of planets, even of gravity itself, based upon small deviations. That said, it certainly includes our ability to use gravity assists when planning a mission.