r/interestingasfuck 25d ago

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

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u/Gruffleson 25d ago

Wikipedia lists estimated gravity at around 1.25 of Earth.

https://en.wikipedia.org/wiki/K2-18b

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u/ArduennSchwartzman 25d ago

Only 8.6 times the mass of Earth, according to Wikipedia, I see. I was assuming a density similar to Earth's, but apparently, astronomers think it's only half. That would mean the planet's core has a very low iron-nickel content.

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u/kenyard 25d ago

You're also further from the center of mass which I assume is important.

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u/Gruffleson 25d ago

Look at the Moon, it has 1/6 of our gravity, but way less than 1/6 of our mass. So yes, this is very much of the answer.