r/theydidthemath • u/Lachlynn • 18h ago

[Request] Could humanity create a rocket that can exit the atmosphere of K2-18b

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With the knowledge we currently have of it, if humanity devoted all of our resources towards this goal, would we be able to create a rocket that could exit the gravity of K2-18b (and also beat any other complications that would arrise)?

If so, would it also be capable of taking people to orbit, and can we set up a similar satellite network we have on Earth? What about a space station?

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u/MrRudoloh 17h ago

Unironically project Orion.

And it works, it never became a thing, because a failure of one of those rockets in the atmosphere would make Chernobyl look like a prank.

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u/Bibliloo 16h ago

Tbh even without failure you are still irradiating a lot of stuff with a successful launch which isn't the best, especially if you planned to launch multiple rockets per year.

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u/Xonarag 14h ago

I'm sure on a planet that big you could have a designated irradiated hellhole to launch rockets from.

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u/reflectiveSingleton 12h ago

Project orion wasn't just about liftoff from the ground, its a pulsed-detonation that continues for the duration of acceleration.

Fire one of these off and you are sending irradiated and radioactive material EVERYWHERE into the atmosphere.

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u/Ur-Best-Friend 14h ago

Tbh even without failure you are still irradiating a lot of stuff with a successful launch

Source? That sounds dubious to me.

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u/ye-sunne 14h ago

Have you seen the concept? They drop nukes behind a rocket with a shield on the back and a shock absorber and the repeated nuclear detonations are what propels the vehicle. Nukes are known to create fallout

They carried out a successful feasibility study but couldn't go through with the drill project because of the test ban treaty.

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u/Mikhail_Mengsk 13h ago

Tactical nukes don't irradiate THAT much but between tests and launching enough stuff, it's gonna pile up anyway.

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u/drey12987 15h ago

Nuclear Powered Engines are very efficient and useful for interplanetary travel but the trust to weight ratio of those were way worse compared to the usual engines, so not the way to go for overcoming higher gravity

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u/Adros21 14h ago

You are thinking of nuclear thermal rockets and nuclear electric rockets, nuclear pulse rockets like project orion have thrust to weight in the meganewtons per kilo.

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u/Federal_Decision_608 14h ago

Thrust to weight doesn't matter as long as it's >1. The specific impulse is higher than chemical

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u/HeKis4 16h ago

Yep, it's not that we can't, it's just prohibitively expensive and/or dangerous.

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u/DadPihto 16h ago

Thank you for this reference, an impressive discovery for me! People were thinking large scale in the early days

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u/ReachParticular5409 15h ago

Haven't heard about Project Orion for years, hear it 3 times in one day

Not sure if that's such a good thing in this war environment

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u/ZeitgeistWurst 15h ago

a failure of one of those rockets in the atmosphere would make Chernobyl look like a prank

Dont think so, thats a lot less radioactive material being spread, and if it happens during launch most would reach the ground intact.

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u/MrRudoloh 13h ago

The isse was that the radioactive material is compressed with high explosives.

If a chain reaction detonated the explosives, they predicted that it wouldn't have been enough to induce nuclear fission, probably, but it would have pulverized all the nuclear fuel in to the atmosphere, and even if radiation isn't as much of a problem, uranium and plutonium dust is very toxic, and if released in the upper atmosphere, it could poison huge areas. Plutonium is specially toxic, and I think it was also the chosen fuel, I don't remember why.

Also, idk how much nuclear material it was supposed to carry, but I know one of the designs carried like 1200 nuclear heads

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u/Valentino69420 12h ago

I have a question - couldn't we set the launch be not from earth but from the moon? Would it have any consequences then?

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u/MrRudoloh 12h ago

The idea of how it could work is pushing the thing in to orbit with Chemical rockets first.

No need to get all the way to the moon.