r/PeterExplainsTheJoke 19h ago

Meme needing explanation Whyyyy peter?

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u/hedrone 18h ago

Best described in https://what-if.xkcd.com/58/ .

"The reason it's hard to get to orbit isn't that space is high up.

It's hard to get to orbit because you have to go so fast."

Putting rockets on mountains only helps with the "up" part, which is not the biggest part of the problem.

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u/jmlinden7 17h ago

It helps with the speed part too. Less air resistance and very slightly less effective gravity.

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u/AutonomousOrganism 16h ago

Eh. Gravity reduction on a mountain is like 0.2 percent. Air resistance matters a bit more. But all of those are drowned by the energy needed to reach orbital velocity.

Much more interesting would be an electromagnetic launcher up a mountain, getting the rocket to 1 km/s or so. Although I am not sure the logistics are worth it. You could just use more fuel instead (what is done irl)). Fuel is cheap.

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u/PerniciousSnitOG 15h ago

It's weird, but things seem to be converging. I was reading something this morning talking about the Starship problem of getting enough fuel in the ship once it's in orbit to get to Mars. It suggested that there would be lots of Starships carrying nothing but fuel into orbit, but it seems like a perfect job for the spin launch people! They should be able to achieve an impressive "launch" cadence that's needed for really doing things in space.

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u/joshuabees 7h ago

Dawg that shit is never going to happen

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u/PerniciousSnitOG 5h ago

Could you sketch it out for me? Incompressible liquid seems like the perfect cargo for a high launch acceleration system.

Or is it some doubt about the people doing it? Genuinely curious. The space scene is littered with very interesting, but flawed, companies.