What is the one thing that you have learned while playing KSP?

[Ryu Gemini]

Orbital Mechanics. I now hate every Sci-Fi movie I watched as a kid.

Why? Any setting which has anti-grav repulsers or something akin to that can get away with it still. After all, if you have an engine capable of making you hover, and an effectively limitless energy supply for that engine, there is little reason why you can't basically just hover over the planet's surface. Even if your altitude is such that you are actually in a vacuum or near-vacuum, while still too low to be a natural geostationary orbit.

Mind you, it is understandable being annoyed with any setting that doesn't have such convenient technology lying around.

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