re: Why the heck would you want to dive down a gravity well in the first place?
I ran an industrial scale process at 3 mmHg with flow rates of 140 lbs per minute at 180C. It's a piece of cake to run even lower vacuum under less demanding circumstances. It should also be obvious that an artificial vacuum can provide a more controlled environment than a natural vacuum flooded with space based energy and particles.
Regards,
Mark
