The part that cannot be simulated by Kerbal Space Program is the fact that the Gateway is not technically orbiting the Moon. It is technically "following" an ar

The part that cannot be simulated by Kerbal Space Program is the fact that the Gateway is not technically orbiting the Moon. It is technically "following" an area of space which is a halo orbit (not really pure orbits in the sense of leave it and forget it, rather where you have to stationkeep (use RCS thrusters a lot)) in an area of 3D space that has nearly the same gravity influence as the L2 LaGrange point does. From: https://www.youtube.com/watch?v=X5O77OV9_ek https://www.youtube.com/watch?v=X5O77OV9_ek at 0:05 The red color orbit around the actual L2 point at 0:05 means that you don't need to stationkeep a whole lot to hold the orbit. As the video continues on, it keeps rendering orbits that are still L2 halo orbits that are unstable as you need to continually stationkeep more and more (the reason behind the color change as I understand it) up until the periapsis of the orbit approaches the moon, the last couple orbits turn red again. This means they are somewhat stable. This is the gateway's planned orbit. At 1:05 it shows what the orbit looks like in 3D earth centered. Now you can see that the station isn't really orbiting the moon, it is in an earth orbit flirting with the South Earth-Moon L2 point. This also means that craft going to the station don't actually need to circularize as you would in a traditional orbit to dock. As long as you time it right that both the gateway and the incoming spacecraft arrive at the gateway's apoapsis at the same time, all you have to do is match their relative velocities and dock. There really is no simple english explanation out there as much as I can find anyways.