Is there a significance for ~100km? Is this, roughly speaking, space -- where the atmosphere is so thin to be almost negligible? Clearly atmosphere thins gradually so how do we define where space starts? Is the significance of ~100km something to do with the effects of gravity at that altitude from the Earth&#x27;s surface? Does ~100km give you weightlessness? Or is Blue Origin going up to ~100km because it&#x27;s a nice round number that is roughly (whatever that means) in space. But aren&#x27;t kilometres completely arbitrary?<p>Also, can people please stop knocking Blue Origin. We get it at this point, okay? I&#x27;m a huge fan of SpaceX and Elon Musk but does Blue Origin have to lose for SpaceX to win? No. There&#x27;s nothing in this post from Bezos bashing SpaceX as far as I can see. There&#x27;s simply saying, look, we did it again with the same refurbished rocket. Good on them. May they do it again and again. And so may SpaceX. The next space race is on, happy days!