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Comment by CrimsonCape | Hacker News Reader

Accounting for acceleration and deceleration seems like an unspoken obstacle in your timeline. How can a human comfortably accelerate or decelerate at a rate greater than 9.8m/s^2 for long periods of time? “Hey guys, we will need you to pull 9Gs for the next seventy years as your ship slows down to enter a stable orbit”

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Accelerating consistently at 1G (and then -1G for the second half), should take 6 years of proper time (from the perspective of the traveller) to get there.

Yea, actually the problem is not at all that we’d need too much acceleration for the human body. Accelerating at 1g for a couple years gets you to preposterous speeds (and we don’t even need any artificial gravity nonsense!). The problem is that accelerating at 1g for years would require a ridiculous amount of energy.

In his 1958 juvenile novel Have Spacesuit, Will Travel (I read it years later as a tween), Robert A. Heinlein described this as a "skew-flip maneuver" that would get someone from Earth to Pluto in five days at 8G (!). And apparently E.E. "Doc" Smith described it even earlier.

https://en.wikipedia.org/wiki/Have_Space_Suit%E2%80%94Will_T...

https://scifi.stackexchange.com/questions/261753/what-was-th...

And because faster acceleration only gives you square-root returns, a leisurely 1G trip going the same distance is still over in 14 days.

Huh. I've heard lots of science fiction ideas for artificial gravity, usually starting with rotating space stations.

I never heard of anything so obviously straightforward as that, though. Surely impractical, but good to know!

You should read the The Expanse books (or watch the show).

Don't they use magnetic boots in the Expanse (at least in the show)?

Only when not under burn.

You just need to be constantly accelerating to hit very high speeds very quickly. You don’t need to pull 9Gs throughout.

I don't think we'll be sending humans on these kinds of missions. We'll be sending AI systems (ship, bots, etc.) and then waiting millennia for them to report back.

It's conceivable that we could send the seeds of humanity and other terrestrial life — along with AI systems capable of raising it, terraforming the planet as necessary, and building a society.

We might not ever travel there or receive guests from New Earth any time in the foreseeable future, but it's fun to imagine that one day we could have a colony of distant pen pals separated by only 20 years of latency.

Under current financial and incentive system this will not going to happen unfortunately.

Or alternatively, we make Alcubierre spacecraft work, or we move our whole planet system.

All entirely plausible approaches :D

I have a feeling that when we figure this out, the forces of acceleration and deceleration will no longer be a problem.

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