Parachutes. From space.

[Simpo Two]

Yes. It's hypothetical and I agreed with you earlier. I was just countering a reply that didn't seem correct.

[tapkaJohnD]

Terminal velocity = SQRT (2 x Mass x g / Density of air x Frontal area x Coeff.drag)

For a human shaped object this is between 120 and 180mph, in the flyable atmosphere.
Alan Eustace, lifted by helium baloon to 135,908ft, got to about 800mph in free-fall.
But that's a LOT less than 17K-mph!

John

[RobDickinson]

Simpo Two said:

I suspect that decelerating in a weightless vacuum would use much less power than accelerating upwards against gravity, but yes, it would of course use fuel that you'd have to carry up.

Some of a rocket launch is to fight atmosphere, but not much of it. Look at the size difference between Bezo's toy and a falcon 9. One goes up to space, and back down again, the other puts things into orbit.

Actually reaching 'space' is easy, its not that far up and doesnt take much, gaining orbit means going very fast, most of that speed in a normal launch is gained outside of appreciable atmosphere