I would imagine that if it were possible to achieve that height for a mountain, the profile would be somewhat different - that’s an immense mass that has to be supported by the earths crust, it would need to be spread out over a much wider area.
I would doubt that it would be possible to be anything like as steep as Everest, probably a much more rounded dome shape which might lend itself to the used of specialised vehicles, and that changes things. Even if they could net reach the very top. they would be able o get within a distance whilst carrying supplies.
Even at that altitude you’re still surrounded by air; you just need a way to pump it into your suit to the required pressure. Assuming you want to do the thing under your own power, you could build foot pumps into your boots. What I’m not sure about is: Would the oxygen you consume carrying the suit and operating the pumps exceed what you were actually able to pump in?
Olympus Mons on Mars is 69,000 feet above datum. The mountain is not particularly steep, and you could probably find a route to walk up it. The entire ascent would be at pressures which require a full pressure suit.
The challenge in using a balloon is to get it to hover above the summit. Not altitude wise, but there’d be all sorts of winds that a lighter than air craft would have to counter. And there’s not enough air up there for propellers to do any good and probably not enough for jet engines. They’d have to use rocket thrusters.
I’m not saying it couldn’t be done, but it’d take a hell of a lot of money to come up with that and they’d need a lot more of a benefit than just being able to say “Because it’s there!”
Well, you know, the Apollo program aside and stuff… :smack:
Jet engines work just fine at 58,000 feet. U2s and (formerly) SR-71s do/did great up there. As do various UAVs.
To be sure there needs to be some design effort to ensure normal function at those altitudes. But it’s a solved problem. Unlike the case for humans where it’s pretty thoroughly past the edge of the envelope and we can’t do the engineering to make modifications to people in the first place.
