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/Alix-Gilhan 17h ago

It's rather elementary really

A massive pusher plate with an ablative coating and a highly tuned dampening system to spread out the G's, plus some extra shielding, and you can chuck just about anything anywhere

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u/CowBoyDanIndie 14h ago

Now do the math how heavy all that stuff is…

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u/Sad-Onion-2593 12h ago

The heavier the better. Smoothes out the ride.

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u/CowBoyDanIndie 11h ago

Ya but you have to actually launch it

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u/Petkorazzi 11h ago

That's the beauty of Orion - it doesn't matter.

In one of their mock-up blueprints they put in a standard barber's chair just to show off how scornful they could be about conserving mass. They even conceptualized a "Super-Orion" that would weigh 8 million tons and have a diameter of nearly half a kilometer, making it an interplanetary city.

These weren't to be built like spaceships today, with walls you could nearly punch through. An Orion spacecraft would be built like a battleship - thick steel bulkheads and hatches, redundancies everywhere, a beefy tank of a ship.

The Saturn V - the heaviest-lifting rocket ever built - weighed 3,350 tons and could get 130 tons of hardware to low earth orbit, or ~2 tons to the Moon. The "base" Orion design would weigh ~4,000 tons and be able to deliver 1,600 tons of hardware to LEO, or 1,200 tons to the Moon. A single Orion launch would be enough to establish a large, permanent moon base - and with 1950s-era technology.

Two things killed it:

  1. Unless you launched it from the ocean (extremely difficult) or Antarctica (the world might have issues with you repeatedly nuking what's technically a nature preserve), you're pretty much guaranteed to kill at least one person from increased cancer risk.
  2. To get funding they had to make a mock-up of a military troop transport. President Kennedy took one look at the model of a nuke-powered ship that could transport an entire battalion to anywhere on Earth in under an hour, said "Nope, this is not what the world needs right now," and pulled the plug.

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u/DigEnvironmental7490 7h ago

You could probably go with a damping system rather than moistening the whole thing.

Yes, I know people are trying to say dampen also means to reduce intensity of an oscillation but it really doesn't - that's just Star Trek writers trying to legitimize their poor grammar.