I watched Shinryuu's tool-assisted speedrun of Mega Man 2 (NES) and noticed an interesting glitch that occurs multiple times throughout the run. I'm curious about how it works and hope someone can explain its mechanics. The glitch first appears at 02:53 in the video. In Heat Man's stage, Mega Man...

Is there a way to do artificial gravity testing of spacecraft on the ground in KSP? If you wanted to, for example, plan for how small the next stage of the flight needs to be for the stage separation + subsequent phase of the flight to succeed. I couldn't find anything mentioning this kind of GSE...