How fast to Alpha Centauri?
Thu, 2010-08-26 19:17
Based on the space travel and combat threads-if somebody decided to travel to Alpha Centauri in EP, using available technology-how fast would he get there ?
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Thu, 2010-08-26 23:56
#2
Re: How fast to Alpha Centauri?
That is also assuming that you are not going fast enough to turn everyone inside into goo from acceleration. Your best bet is to send a memory core with synth bodies in storage to Alpha Centauri and then resleeve them when you arrive. Even then your looking at close to a 300 year voyage.
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Fri, 2010-08-27 08:03
#3
Re: How fast to Alpha Centauri?
The distance to AC is 4.3 lightyears, or 4*10^13 km. A fast courier has a total Delta V of 1,600 km/sec using anti-matter rockets, so if it uses half of this to accelerate and half to stop, it will get to AC in a mere 1611 years! The acceleration could be as gentle as you want it, the main thing is that you want *a lot* of velocity.
A real starship could probably push this by having an even more absurd amount of fuel (isp is hard to increase beyond antimatter) but likely the best way is to miniaturize everything: everything would be solid state and nanomachines. Passengers would be infomorphs (running in slowtime or just stored), and the cargo would be nanotech to build a base on some suitable body upon arrival. Given that the courier can take 13 humans, I think we can safely assume this kind of nanostarship could reduce the payload weight by at least a factor of 1/100. That would boost speed by a factor of 4.6 (350 years). If we miniaturize further, assuming a factor of 1/10,000 smaller payload, then we can go 9.2 times faster, arriving in 175 years. Adding a hundred times more reaction mass too gives us just a factor of 13.8, 116 years.
(Rocket equation, I hate you! 
)
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Fri, 2010-08-27 08:41
#4
Re: How fast to Alpha Centauri?
Of course this whole debate is useless if there isn't any suitable land to colonize when you get there.
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Fri, 2010-08-27 09:06
#5
Re: How fast to Alpha Centauri?
You could cut a lot more if you didn't bother bringing enough fuel to decelerate.
Sat, 2010-09-04 02:24
#6
Re: How fast to Alpha Centauri?
Or if you have some other means of deceleration, like a magsail.
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Sun, 2010-09-05 22:17
#7
Re: How fast to Alpha Centauri?
root@How fast to Alpha Centauri
It would take 4.3 years. If you just focus a really large communicator into that region, and keep egocasting alphas in that direction, someone might pick up. Would those alphas be called Egonauts do you think?
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Tue, 2010-09-07 07:20
#8
Re: How fast to Alpha Centauri?
with an Isp of 200,000 (re; Jsnead) I find that the exhaust velocity of EP's antimater engines is 1962000m/s
Plug that and the DeltaV into the Tsiolkovsky equasion;
I find that the propelent mass ratio is a rather low 1.5
since the optimal mass ratio sould be around 4.5 it seems that the DeltaVcap could be as high as 2900km/s
However; Everything I've learned about the subject I got from the Atomic rockets page so I'm a bit confused by the Isp # given for Antimater Plasma engines with hydrogen propelant. I thought that the Exhaust velocity for those engines would be 7,840,000m/s
here's a link
http://www.projectrho.com/rocket/rocket3c2.html
PS: jsnead;
I'd like to extend my heartfelt gratitude to you for supplying those numbers for DeltaV and Isp. I was going fucking buggy trying to figgure it out for myself.
Thanks Dude! 
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I vaguely remember from high school Physics that it's 4.3 light years. If there was someone set up to receive a quantum farcast there already, it'd take 4.3 years. Otherwise ... well, light travels at 186,000 miles per second. How fast are the fastest ships in EP?