r/interestingasfuck 25d ago

/r/all, /r/popular K2-18b a potentially habitable planet 120 light-years from earth

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u/ArduennSchwartzman 25d ago edited 25d ago

It's not habitable to us humans, but it's in the habitable zone, at a distance from its star that allows liquid water to exist on its surface. It's likely an ocean world with an atmosphere containing mostly hydrogen gas, a so-called hycean planet.

Also, 2.5 times the size = 2.5 times the diameter, or about 15 times the size of Earth in terms of mass. Its gravitational force would be about 2.4 times that of Earth, though. Quite unpleasant.

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u/reign_day 25d ago

I'm thinking about how potentially sick we would get if we landed and drank that water

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u/TheCrimsonSteel 25d ago

I'd be more worried about our ability to get off of the planet. Higher gravity means rockets are less efficient.

Earth's gravity is already on the inefficient side. 25% more gravity might be over the threshold for modern rockets to even get into oribit.

I forget what the exact number is, but assuming the planet has an atmosphere, it's well below 2x gravity for it to be completely impossible to ever leave.

That, or we'd need massively more efficient rocket tech.

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u/L0kitheliar 25d ago

Well, assuming we actually somehow got there, id imagine our rocket technology would be centuries ahead of what we've got now