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A comment on Earth-like planet spotted orbiting Sun’s closest star. Parent comment

Re:Earth-like planet spotted orbiting Sun’s closest star by messe on Friday February 11, 2022 @08:07AM (#30300967)
> If we ever figure out light-weight fusion drives, we could build light hugger space ships that accelerate to a decent fraction of the speed of light. At 1g acceleration it takes about one year to get to 0.9c, which would make the Proxima system accessible with a travel time of about 6 years. Or 8 years at 0.5g. Or 9 years if we 'only' get to 0.5c.

No, we couldn't. The energy density of fusion isn't anywhere near close enough to make a lighthugger, you'd need insane mass ratios[1] and ramjets are probably unfeasible (as in, even-if-your-a-Kardeshev-II-civilization-unfeasible[2]).

[1]: http://www.projectrho.com/public_html/rocket/slowerlight3.ph...

[2]: https://www.sciencedirect.com/science/article/pii/S009457652...

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Re:Earth-like planet spotted orbiting Sun’s closest star by thereddaikon on Friday February 11, 2022 @08:57AM (#30301522)
Another atomic rockets enjoyer. I've killed so much time on that site. I don't agree with every one of Winchell's conclusions. But they are small things. And I don't know of a more comprehensive and grounded take on future spaceflight technologies.
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Re:Earth-like planet spotted orbiting Sun’s closest star by messe on Friday February 11, 2022 @11:44AM (#30303553)
I was saddened to hear about Winchell's cancer diagnosis last year[1]. I've wasted a ton of time there too, it's an oddity compared to the rest of the modern internet. I know very few other useful sites like it, and I love it all the more for its strange aesthetic.

I don't agree with everything there either, but usually it's only very minor gripes. In this case though, it's hard to argue with the reality of the rocket equation.

[1]: https://twitter.com/nyrath/status/1436010987086286853?s=20

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Re:Earth-like planet spotted orbiting Sun’s closest star by thereddaikon on Friday February 11, 2022 @01:40PM (#30305333)
Oh man, I hadn't heard about that. Best of luck to him but he's right prostate cancer is a pretty bad one.

What are the other few sites you do know of?

And you are absolutely right about the rocket equation. You can't really get around it.

[ Parent | on HN ]
Re:Earth-like planet spotted orbiting Sun’s closest star by messe on Friday February 11, 2022 @03:03PM (#30306339)
I'm sure there's more but the first few that come to mind are Greg Egan's homepage[1], Xenology[2], and on a completely different topic "Gramadach na Gaeilge"[3] (Irish Grammar).

[1]: https://gregegan.net

[2]: https://xenology.info

[3]: http://nualeargais.ie/gnag/gram.htm

[ Parent | on HN ]
Re:Earth-like planet spotted orbiting Sun’s closest star by messe on Friday February 11, 2022 @07:46PM (#30308859)
It's too late to edit, but the link to xenology should be http and not https:

[2]: http://xenology.info

[ Parent | on HN ]