While space is often referred to as a vacuum, it isn't completely empty.
Even most rocket scientists would rather avoid hard math when they don’t have to do it. So when it comes to figuring out orbits in complex three-body systems, like those in Cis-lunar space, which is between the Earth and the Moon, they’d rather someone else do the work for them. Luckily, some scientists at Lawrence Livermore National Laboratory seems to have a masochistic streak - or enough of an altruistic one that it overwhelmed the unpleasantness of doing the hard math - to come up with an open-source dataset and software package that maps out 1,000,000 cis-lunar orbits.
