> It was an air bearing in a reduced (but still fairly high) pressure tube. You are a funny guy :) According to the source [0], the pressure was intended to be

> It was an air bearing in a reduced (but still fairly high) pressure tube. You are a funny guy :) According to the source [0], the pressure was intended to be 100 Pa ("about 1/6 the pressure of the atmosphere of Mars"). Technically speaking, this is a fairly good medium vacuum [1]. The term "vacuum" itself refers to "a space from which most of the air or gas has been removed" [2], so you don't have to go into the intergalactic void to achieve it. I think ~99.9% qualifies as "most" :D [0] https://www.tesla.com/sites/default/files/blog_images/hyperloop-alpha.pdf https://www.tesla.com/sites/default/files/blog_images/hyperl... pg. 12 [1] https://en.wikipedia.org/wiki/Vacuum https://en.wikipedia.org/wiki/Vacuum [2] https://dictionary.cambridge.org/dictionary/english/vacuum https://dictionary.cambridge.org/dictionary/english/vacuum