Re: Travelling the Stars

Michael Lorrey (
Thu, 10 Dec 1998 18:08:50 -0500

Dan Fabulich wrote:

> As I believe Haradon mentioned, but which could use further emphasis, you
> can get anywhere in the universe in an arbitrarily short amount of time, as
> measured by the traveler. No weird physics is involved here; just get
> yourself the fastest engine you can, and go. The faster the engine, the
> sooner you'll get there, from your own perspective.

Actually, it was me who mentioned the time dilation gag.

> If you had a fast enough engine, (in the conventional sense of the word
> "fast") you could get to alpha centuri (4.6 light years away) in six months
> or even less using conventional thrust and acceleration.

Actually, that would be at a higher than normal G level. At 1 G constant thrust you would have gone .7 light years in a year...a 2 G acceleration would do it to AC in 1.4 years, but I don't know many people who could stand 2 Gs for a whole year....

> The weird physics only comes in when I tell you that this is true from YOUR
> perspective only; everybody else would see you travelling at sub light
> speed. But who cares? You'd only have to bring six months worth of food,
> six months worth of reading material, etc. and as far as you cared, you'd
> be there in six months.

Yeah, the only downside is that it will take 9 hours to receive 1 hour of South Park transmissions from Earth.....damn, better stock up ahead of time....

> Of course, as others have pointed out, this isn't particularly efficient;
> you'd likely be better off going there more slowly and sleeping most of the
> way.

The only thing that bugs me about going slow and sleeping through it is that since you aren't accelerating at any appreciable G level, you will either have to deal with cardiovascular and bone degeneration caused by long term low G exposure, or have a rotating hull. A rotating hull puts in other problems: long term exposure to such tight coriolis forces permanently messes up your sense of balance, since your ears will adjust to the new environment, but won't adjust all the way back when you are finished. If you are using a Bussard Ramjet as your propulsion system, then the rotating habitat will generate all sorts of induction currents passing through the ram scoop field constantly.

Yes, it would be more energy efficient to go slower. However, energy does not seem to be that big of a problem in space. Mass is the problem. Being mass efficient in your propulsion system is what is truly important, since there isn't much out there to refuel with.

Mike Lorrey