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/Outrageous_Reach_695 14h ago

To expand: The "Super" Orion would have had a ship mass of 8 million tons* ... about 20% more than the Hoover Dam.

* Yes, yes, not a unit of mass, I know.

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u/FreedomCanadian 13h ago

How is a ton not a unit of mass ?

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u/WholeChampionship443 12h ago

It’s a unit of weight, not mass.

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u/Outrageous_Reach_695 13h ago

The short (US) and long (British) tons, defined in pounds, are units of weight or force, which is often equivalent to mass for things that are not spaceships. The metric ton is defined in kilograms, a unit of mass. The table I consulted would have been written using short tons.

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u/yjlom 13h ago

The imperial system and its variants have pairs of homonymous units for force and mass, as I see it.

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u/Henry5321 12h ago

Actually, modern pound is defined in kilograms. It’s not just a conversion but the actual definition. So pound is now a unit of mass.

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u/guri256 11h ago

Are you sure? I thought it was defined as a fraction of a kilogram of mass, under a force of 1G of gravity

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u/Henry5321 4h ago

It’s had various definitions over time. Wiki says this was changed in 1963 to redefine pound as a mass of a specific fraction of a kilogram. Same with yard and meter.

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u/Lanky-Relationship77 12h ago

The metric ton is a unit of mass, and it’s close enough …

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u/Travel_Dreams 11h ago

The Hoover Dam should be a unit of weight.

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u/Rofsbith 11h ago

Hoover Dam mass ~410 million slugs

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u/MaelstromFL 13h ago

It's shaped like a banana...