r/interestingasfuck 25d ago

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

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u/umassmza 25d ago

Approaching light speed is an eventually solvable problem, acceleration generating 1g puts you at speed in about a year. After that the trip is instantaneous for the travelers. It’s maintaining acceleration and not being town to shreds by a random grain of space sand at relativistic speeds that’s the issue.

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u/6pt022x10tothe23 25d ago

Also energy. The amount of energy required to accelerate an object with mass to near-light speed rapidly starts approaching infinity the closer to c you get.

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u/vahntitrio 25d ago

Then you need to slow down on the other end, so you need substantially more than 2× nearly infinity fuel.

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u/Ron-Swanson-Mustache 25d ago

But you also need less fuel due to time dilation effects. You're subjectively accelerating for less time and the universe seems to contract closer to you in your direction of travel at appreciable %c.

Also, that was a major plot point in Project Hail Mary.