Pretty cool. Too bad interstellar travel is so damned impractical. At least we now have a decent guess for a destination when we get our first probe.
Barring some unforeseen physics breakthrough, we'll probably have telescopes capable of identifying with near certainty a world that already contains life before we're capable of traveling through interstellar space. This discovery is important not because it gives us somewhere to go but because it indicates that these sorts of worlds (small, rocky ones) are not astronomically rare. It's not really a big shock (we were expecting that anyway, what with having four of them in our own inner solar system), but it is one more piece of the puzzle.
Of course, it's entirely possible that we'll find life elsewhere within our own solar system before too long anyway.
Or someone else finds us.
Personally, I'm hoping we find a race of MASSIVE space whales under that ice in Europa. Like the size of cities. Something so huge and alien that mankind hasn't been able to imagine it before.
Then we'll ride them as steeds to new solar systems! ... But the Japanese will of course hunt them to extinction not long after they're discovered.
Still requires you to get to around 99.99% of the speed of light before it's usable, which is beyond the capabilities of any known or projected propulsion system. I guess maybe a really insane battery of lasers near Sol pushing on a solar sail might work, but that'd take an engineering program of a truly enormous scale. It's also technically possible that you could achieve this with antimatter, I guess, but I wouldn't bet on it.
Not really. Maybe I did the math wrong, but in the example of 82 years going more or less 66% of c (unless I misunderstood tbloxham's post) it should shave it down to only 60 something years for the people on the ship. Which is still a long time, but 20 years is nothing to sneeze at.
HamHamJ on
While racing light mechs, your Urbanmech comes in second place, but only because it ran out of ammo.
Pretty cool. Too bad interstellar travel is so damned impractical. At least we now have a decent guess for a destination when we get our first probe.
Barring some unforeseen physics breakthrough, we'll probably have telescopes capable of identifying with near certainty a world that already contains life before we're capable of traveling through interstellar space. This discovery is important not because it gives us somewhere to go but because it indicates that these sorts of worlds (small, rocky ones) are not astronomically rare. It's not really a big shock (we were expecting that anyway, what with having four of them in our own inner solar system), but it is one more piece of the puzzle.
Of course, it's entirely possible that we'll find life elsewhere within our own solar system before too long anyway.
Or someone else finds us.
Personally, I'm hoping we find a race of MASSIVE space whales under that ice in Europa. Like the size of cities. Something so huge and alien that mankind hasn't been able to imagine it before.
Still requires you to get to around 99.99% of the speed of light before it's usable, which is beyond the capabilities of any known or projected propulsion system. I guess maybe a really insane battery of lasers near Sol pushing on a solar sail might work, but that'd take an engineering program of a truly enormous scale. It's also technically possible that you could achieve this with antimatter, I guess, but I wouldn't bet on it.
Not really. Maybe I did the math wrong, but in the example of 82 years going more or less 66% of c (unless I misunderstood tbloxham's post) it should shave it down to only 60 something years for the people on the ship. Which is still a long time, but 20 years is nothing to sneeze at.
No, it looks like you've got the math about right (although using 82 years in this case is a strange choice, since you've also assumed you'd be traveling at 0.66c the whole time, which would give you a travel time of 33.3 years).
The problem is that a 33-year travel time is still unmanageable without suspended animation or some similar technology (or a really, really big ship). Also, 0.66c is an insanely high velocity, and likely beyond our ability (short of huge batteries of lasers or something like that). For reference, with fusion rockets (also currently beyond our ability), about 0.1c would be the most we could reasonably obtain. That's incredibly fast, but still not fast enough for time dilation to matter or for us to get anywhere within human timescales as they are presently understood.
Also, remember that the Gliese system is really, really close as these things go. It's 20 light years away, while our galaxy is 100,000 light years across. Most places won't be nearly so easy to reach.
CycloneRanger on
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HonkHonk is this poster.Registered User, __BANNED USERSregular
edited April 2009
How about Proxima Centauri, that's the closest star system right? Have they found any planets at all over there?
Still requires you to get to around 99.99% of the speed of light before it's usable, which is beyond the capabilities of any known or projected propulsion system. I guess maybe a really insane battery of lasers near Sol pushing on a solar sail might work, but that'd take an engineering program of a truly enormous scale. It's also technically possible that you could achieve this with antimatter, I guess, but I wouldn't bet on it.
No no, time dilation plays a role at around 0.1c. 0.9c shortens the passengers trip by a factor of 2, 0.95 by a factor of 3, 0.99 by a factor of 10.... etc. 99.99% compresses time by a factor of over 70 for passengers. This is certainly usable, but I'd say cutting your trip in half also counts as usable.
[Tycho?] on
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KageraImitating the worst people. Since 2004Registered Userregular
All future spacecraft will be equipped with a 100,000 gallon tub of water and a priest.
ElJeffe on
I submitted an entry to Lego Ideas, and if 10,000 people support me, it'll be turned into an actual Lego set!If you'd like to see and support my submission, follow this link.
Still requires you to get to around 99.99% of the speed of light before it's usable, which is beyond the capabilities of any known or projected propulsion system. I guess maybe a really insane battery of lasers near Sol pushing on a solar sail might work, but that'd take an engineering program of a truly enormous scale. It's also technically possible that you could achieve this with antimatter, I guess, but I wouldn't bet on it.
No no, time dilation plays a role at around 0.1c. 0.9c shortens the passengers trip by a factor of 2, 0.95 by a factor of 3, 0.99 by a factor of 10.... etc. 99.99% compresses time by a factor of over 70 for passengers. This is certainly usable, but I'd say cutting your trip in half also counts as usable.
I'm familiar with the equations. What I meant was, you have to be somewhere around 99.8 or .9% of c before you can count on it as a means to reduce the apparent trip time enough on its own. Slowing the trip time by a factor of two doesn't matter when that still leaves you with a 40-year trip; you're still going to have to either freeze everyone or build a really huge ship.
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HonkHonk is this poster.Registered User, __BANNED USERSregular
All future spacecraft will be equipped with a 100,000 gallon tub of water and a priest.
I'd just strap the pope to the front of my ship.
Sounds like something out of 40k.
Why not just drink the holy water? Or, alternately, just bless a person in the first place. Or you could put it through a humidifier to presumably protect the entire ship.
CycloneRanger on
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KageraImitating the worst people. Since 2004Registered Userregular
All future spacecraft will be equipped with a 100,000 gallon tub of water and a priest.
I'd just strap the pope to the front of my ship.
Sounds like something out of 40k.
Why not just drink the holy water? Or, alternately, just bless a person in the first place. Or you could put it through a humidifier to presumably protect the entire ship.
All future spacecraft will be equipped with a 100,000 gallon tub of water and a priest.
I'd just strap the pope to the front of my ship.
Sounds like something out of 40k.
Why not just drink the holy water? Or, alternately, just bless a person in the first place. Or you could put it through a humidifier to presumably protect the entire ship.
Because once you piss it our you're fucked.
There's no pissing in hell. You feel like you've got to go, but you just can't squeeze anything out.
I'm sure there's a chapter in the old testament about it.
All future spacecraft will be equipped with a 100,000 gallon tub of water and a priest.
I'd just strap the pope to the front of my ship.
Sounds like something out of 40k.
Why not just drink the holy water? Or, alternately, just bless a person in the first place. Or you could put it through a humidifier to presumably protect the entire ship.
Because once you piss it our you're fucked.
There's no pissing in hell. You feel like you've got to go, but you just can't squeeze anything out.
I'm sure there's a chapter in the old testament about it.
There's no hell in Judaism, so it's either new or one of those parts Christians added after the fact.
Is there any way to accelerate at the rates we're talking about w/o being turned to mush? If not, maybe the best thing to do is to accelerate at 1g for 10 light years and decelerate at 1g for the next ten.
Still requires you to get to around 99.99% of the speed of light before it's usable, which is beyond the capabilities of any known or projected propulsion system. I guess maybe a really insane battery of lasers near Sol pushing on a solar sail might work, but that'd take an engineering program of a truly enormous scale. It's also technically possible that you could achieve this with antimatter, I guess, but I wouldn't bet on it.
Not really. Maybe I did the math wrong, but in the example of 82 years going more or less 66% of c (unless I misunderstood tbloxham's post) it should shave it down to only 60 something years for the people on the ship. Which is still a long time, but 20 years is nothing to sneeze at.
Its not 66% of c unfortunately, its about 40% of c at maximum speed, where you will spend 33% of your time. The ship I described is also unfortunately not practical, it requires the mass production and safe storage of antimatter in ludicrous quantities. To get 100 kg of ship to this planet in 82 years would require 450 kg of anti matter, which even if we can do matter to energy conversion requires 4e19 joules of energy. This is the total energy produced by all earth sources (solar, tidal and geothermal) for 4 minutes. Which is quite a lot.
The problem is that although your true 'maximum' speed is C, you need to carry fuel to speed up, and by the standards of going really really fast even antimatter is pretty low energy density. Even without relativity think about it like this, each extra joule of energy you add speeds you up less than the one before did. To get close to C you need to not have to carry your fuel with you. Now, extrapolating from current tech we could perhaps build a giant space laser and use it to impel the ship remotely, but it would still need to be carrying 50% of the required antimatter to stop quickly.
(this is all aproximate, because mass of the ship changes continually as fuel is used, and that makes the equations hard to solve)
A possible ship design is an orion drive system which would be a TITANIC construction weighing millions of tonnes and carrying thousands upon thousands of nuclear bombs. It might be able to top out its speed at 0.1 c, since nuclear bombs are about 8% as good as antimatter explosions. So it would likely take more than 250 years or so to get there.
tbloxham on
"That is cool" - Abraham Lincoln
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ShogunHair long; money long; me and broke wizards we don't get alongRegistered Userregular
edited April 2009
But man if we bork that orion drive and in the lift from the surface to space it blows the entire planet is done.
There's no pissing in hell. You feel like you've got to go, but you just can't squeeze anything out.
I'm sure there's a chapter in the old testament about it.
There's no hell in Judaism, so it's either new or one of those parts Christians added after the fact.
Is there any way to accelerate at the rates we're talking about w/o being turned to mush? If not, maybe the best thing to do is to accelerate at 1g for 10 light years and decelerate at 1g for the next ten.
1 g of acceleration, if you could sustain it, would get you to 0.5c in less than half a year. Acceleration isn't really the critical problem (although high accelerations are necessary to get the most out of certain gravity assist maneuvers).
But man if we bork that orion drive and in the lift from the surface to space it blows the entire planet is done.
I'm not talking al dente spaghetti done either.
Like stick a fucking fork in her; we're done.
Any practical orion-type propulsion system for interstellar travel would use fusion reactions for power, probably initiated using powerful lasers. There's no reason to think it would go off on launch; and besides, there's no reason we have to launch it all at once.
So ambitious for a species that hasn't even visited the planets in its own solar system . . .
The other planets are like Mississippi. Sure, you could go there if you wanted to, but why would you?
Well, we are going there. Current plans call for a return to the moon in the 2020's by NASA, and from there a manned expedition to Mars (which would actually be quite different from the Apollo program in many ways, but I guess that's another topic) in the coming years.
I don't quite think the Moon is a necessary intermediate step, but if that's what it takes to get everyone on board, well, that's what it takes. So much of this is politics now, anyway. It's depressing.
There's no pissing in hell. You feel like you've got to go, but you just can't squeeze anything out.
I'm sure there's a chapter in the old testament about it.
There's no hell in Judaism, so it's either new or one of those parts Christians added after the fact.
Is there any way to accelerate at the rates we're talking about w/o being turned to mush? If not, maybe the best thing to do is to accelerate at 1g for 10 light years and decelerate at 1g for the next ten.
1 g of acceleration, if you could sustain it, would get you to 0.5c in less than half a year. Acceleration isn't really the critical problem (although high accelerations are necessary to get the most out of certain gravity assist maneuvers).
How long would it take if we accelerated at 1g for half the voyage and then slowed back down over the second half (I'm assuming that speeds will stay low enough that force will still equal acceleration)?
So ambitious for a species that hasn't even visited the planets in its own solar system . . .
The other planets are like Mississippi. Sure, you could go there if you wanted to, but why would you?
Well, we are going there. Current plans call for a return to the moon in the 2020's by NASA, and from there a manned expedition to Mars (which would actually be quite different from the Apollo program in many ways, but I guess that's another topic) in the coming years.
I don't quite think the Moon is a necessary intermediate step, but if that's what it takes to get everyone on board, well, that's what it takes. So much of this is politics now, anyway. It's depressing.
I think we should concentrate more on the ISS. If we can build a spacedock, we can do whatever we want. And then we can make it into a giant ring and live there.
There's no pissing in hell. You feel like you've got to go, but you just can't squeeze anything out.
I'm sure there's a chapter in the old testament about it.
There's no hell in Judaism, so it's either new or one of those parts Christians added after the fact.
Is there any way to accelerate at the rates we're talking about w/o being turned to mush? If not, maybe the best thing to do is to accelerate at 1g for 10 light years and decelerate at 1g for the next ten.
1 g of acceleration, if you could sustain it, would get you to 0.5c in less than half a year. Acceleration isn't really the critical problem (although high accelerations are necessary to get the most out of certain gravity assist maneuvers).
How long would it take if we accelerated at 1g for half the voyage and then slowed back down over the second half (I'm assuming that speeds will stay low enough that force will still equal acceleration)?
They won't stay low enough. The Gliese 581 system is 20 LY away, so there's a minimum trip time of 20 years. If you could sustain 1 g of acceleration for even 1 full year you'd hit the speed of light.
Of course, it's impossible to sustain an acceleration like that, because the energy cost increases toward infinity (which occurs at the speed of light).
So ambitious for a species that hasn't even visited the planets in its own solar system . . .
The other planets are like Mississippi. Sure, you could go there if you wanted to, but why would you?
Well, we are going there. Current plans call for a return to the moon in the 2020's by NASA, and from there a manned expedition to Mars (which would actually be quite different from the Apollo program in many ways, but I guess that's another topic) in the coming years.
I don't quite think the Moon is a necessary intermediate step, but if that's what it takes to get everyone on board, well, that's what it takes. So much of this is politics now, anyway. It's depressing.
I think we should concentrate more on the ISS. If we can build a spacedock, we can do whatever we want. And then we can make it into a giant ring and live there.
The ISS is a good idea, but poorly executed and parasitically attached to the equally feeble Shuttle program. I'm not particularly fond of it for many reasons.
And I don't have any idea what you mean by a "spacedock" (we've been docking things in space since Apollo), but making a giant ring would take far more material than we could conceivably heft into orbit using today's methods. It would be simpler to colonize Mars, not to mention more productive from a scientific standpoint. Mars is actually a much, much nicer place than LEO; it's just more distant.
There's no pissing in hell. You feel like you've got to go, but you just can't squeeze anything out.
I'm sure there's a chapter in the old testament about it.
There's no hell in Judaism, so it's either new or one of those parts Christians added after the fact.
Is there any way to accelerate at the rates we're talking about w/o being turned to mush? If not, maybe the best thing to do is to accelerate at 1g for 10 light years and decelerate at 1g for the next ten.
1 g of acceleration, if you could sustain it, would get you to 0.5c in less than half a year. Acceleration isn't really the critical problem (although high accelerations are necessary to get the most out of certain gravity assist maneuvers).
How long would it take if we accelerated at 1g for half the voyage and then slowed back down over the second half (I'm assuming that speeds will stay low enough that force will still equal acceleration)?
They won't stay low enough. The Gliese 581 system is 20 LY away, so there's a minimum trip time of 20 years. If you could sustain 1 g of acceleration for even 1 full year you'd hit the speed of light.
Of course, it's impossible to sustain an acceleration like that, because the energy cost increases toward infinity (which occurs at the speed of light).
Is there any way to calculate how long it would take w/ one g of force, then? Basically I want to know how long it would take if all artificial gravity was supplied by the engines.
So ambitious for a species that hasn't even visited the planets in its own solar system . . .
The other planets are like Mississippi. Sure, you could go there if you wanted to, but why would you?
Well, we are going there. Current plans call for a return to the moon in the 2020's by NASA, and from there a manned expedition to Mars (which would actually be quite different from the Apollo program in many ways, but I guess that's another topic) in the coming years.
I don't quite think the Moon is a necessary intermediate step, but if that's what it takes to get everyone on board, well, that's what it takes. So much of this is politics now, anyway. It's depressing.
I think we should concentrate more on the ISS. If we can build a spacedock, we can do whatever we want. And then we can make it into a giant ring and live there.
The ISS is a good idea, but poorly executed and parasitically attached to the equally feeble Shuttle program. I'm not particularly fond of it for many reasons.
And I don't have any idea what you mean by a "spacedock" (we've been docking things in space since Apollo), but making a giant ring would take far more material than we could conceivably heft into orbit using today's methods. It would be simpler to colonize Mars, not to mention more productive from a scientific standpoint. Mars is actually a much, much nicer place than LEO; it's just more distant.
I meant spacedrydock.
And the ring was just an allusion to Ringworld. That's a well known series, right?
The ISS is a good idea, but poorly executed and parasitically attached to the equally feeble Shuttle program. I'm not particularly fond of it for many reasons.
Yes, I'm rather of the opinion that fuck the ISS right in its stupid ear with a space shuttle.
ElJeffe on
I submitted an entry to Lego Ideas, and if 10,000 people support me, it'll be turned into an actual Lego set!If you'd like to see and support my submission, follow this link.
There's no pissing in hell. You feel like you've got to go, but you just can't squeeze anything out.
I'm sure there's a chapter in the old testament about it.
There's no hell in Judaism, so it's either new or one of those parts Christians added after the fact.
Is there any way to accelerate at the rates we're talking about w/o being turned to mush? If not, maybe the best thing to do is to accelerate at 1g for 10 light years and decelerate at 1g for the next ten.
1 g of acceleration, if you could sustain it, would get you to 0.5c in less than half a year. Acceleration isn't really the critical problem (although high accelerations are necessary to get the most out of certain gravity assist maneuvers).
How long would it take if we accelerated at 1g for half the voyage and then slowed back down over the second half (I'm assuming that speeds will stay low enough that force will still equal acceleration)?
They won't stay low enough. The Gliese 581 system is 20 LY away, so there's a minimum trip time of 20 years. If you could sustain 1 g of acceleration for even 1 full year you'd hit the speed of light.
Of course, it's impossible to sustain an acceleration like that, because the energy cost increases toward infinity (which occurs at the speed of light).
Is there any way to calculate how long it would take w/ one g of force, then? Basically I want to know how long it would take if all artificial gravity was supplied by the engines.
Uh; "g" is a unit of acceleration, not force. I'm not sure what you mean here. To maintain 1 g as observed in your starting reference frame, you need an increasing amount of energy (tending toward infinity as your speed approaches c).
My understanding of relativity (I am not a physicist) indicates that the crew of the spacecraft would not perceive things in quite this manner, since the effects of time dilation would allow them to continue to perceive the same acceleration for an arbitrary period of time and at the same energy cost.
CycloneRanger on
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HarrierThe Star Spangled ManRegistered Userregular
I haven't really heard anyone ever talk about it(like anywhere), but how do relativistic speeds effect impulse for deceleration? Like, is it easier to push it back down the hill? I know there is less mass, so you can decelerate faster with the same force, but ignoring that do you still pick up some efficiency(not technically the correct term)? Does it work the other way, because whatever you are using in the rocket can only go so much faster than you or is the force tied you your frame of reference?
redx on
They moistly come out at night, moistly.
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RingoHe/Hima distinct lack of substanceRegistered Userregular
I haven't really heard anyone ever talk about it(like anywhere), but how do relativistic speeds effect impulse for deceleration? Like, is it easier to push it back down the hill? I know there is less mass,
High velocities actually increase mass. For a spacecraft burning some kind of fuel, though, the total mass at the end of it's journey will of course be lower (which may be what you're talking about here).
so you can decelerate faster with the same force, but ignoring that do you still pick up some efficiency(not technically the correct term)? Does it work the other way, because whatever you are using in the rocket can only go so much faster than you or is the force tied you your frame of reference?
In your frame of reference, everything seems totally normal. You feel whatever forces and accelerations would happen normally here on Earth. Your rate of time passage is quite different from what an observer on Earth would report, of course.
I think I see what you're asking, though, and the answer is "no". Once you've got yourself up to a really high velocity, it's just as hard (energy-intensive) to slow down as it was to get there in the first place (except that you're carrying less fuel, since you burned half of it on the way in—standard rocket equation stuff).
CycloneRanger on
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HarrierThe Star Spangled ManRegistered Userregular
edited April 2009
Honest-to-god propulsion systems at high interstellar speeds are too much of a headache. We're better off hacking away at building some kind of warp drive.
Harrier on
I don't wanna kill anybody. I don't like bullies. I don't care where they're from.
In your frame of reference, everything seems totally normal. You feel whatever forces and accelerations would happen normally here on Earth. Your rate of time passage is quite different from what an observer on Earth would report, of course.
I think I see what you're asking, though, and the answer is "no". Once you've got yourself up to a really high velocity, it's just as hard (energy-intensive) to slow down as it was to get there in the first place (except that you're carrying less fuel, since you burned half of it on the way in—standard rocket equation stuff).
Honest-to-god propulsion systems at high interstellar speeds are too much of a headache. We're better off hacking away at building some kind of warp drive.
Yes, we are better off magically getting there instantly. But until we can do that, it probably does help to think of other ways.
I mean, yeah it blows chunks that it's so ridiculously far, but saying we should wait for warp is like looking at a canoe and saying we should wait for the Concord.
Edit: Or actually, like looking at a canoe and saying we should wait for a warp drive.
Posts
Then we'll ride them as steeds to new solar systems! ... But the Japanese will of course hunt them to extinction not long after they're discovered.
Not really. Maybe I did the math wrong, but in the example of 82 years going more or less 66% of c (unless I misunderstood tbloxham's post) it should shave it down to only 60 something years for the people on the ship. Which is still a long time, but 20 years is nothing to sneeze at.
You just imagined it though.
The problem is that a 33-year travel time is still unmanageable without suspended animation or some similar technology (or a really, really big ship). Also, 0.66c is an insanely high velocity, and likely beyond our ability (short of huge batteries of lasers or something like that). For reference, with fusion rockets (also currently beyond our ability), about 0.1c would be the most we could reasonably obtain. That's incredibly fast, but still not fast enough for time dilation to matter or for us to get anywhere within human timescales as they are presently understood.
Also, remember that the Gliese system is really, really close as these things go. It's 20 light years away, while our galaxy is 100,000 light years across. Most places won't be nearly so easy to reach.
No no, time dilation plays a role at around 0.1c. 0.9c shortens the passengers trip by a factor of 2, 0.95 by a factor of 3, 0.99 by a factor of 10.... etc. 99.99% compresses time by a factor of over 70 for passengers. This is certainly usable, but I'd say cutting your trip in half also counts as usable.
But then we'd have to pass through hell.
Maybe if we coat it in holy water.
http://www.youtube.com/watch?v=KJ2yRTRlMFU
Really, just the first 20 seconds ... but dammit if I can't watch the whole thing again.
3DS FC: 4699-5714-8940 Playing Pokemon, add me! Ho, SATAN!
All future spacecraft will be equipped with a 100,000 gallon tub of water and a priest.
I'd just strap the pope to the front of my ship.
Sounds like something out of 40k.
Because once you piss it our you're fucked.
There's no pissing in hell. You feel like you've got to go, but you just can't squeeze anything out.
I'm sure there's a chapter in the old testament about it.
[ This thread approved by the Space Pope ]
3DS FC: 4699-5714-8940 Playing Pokemon, add me! Ho, SATAN!
There's no hell in Judaism, so it's either new or one of those parts Christians added after the fact.
Is there any way to accelerate at the rates we're talking about w/o being turned to mush? If not, maybe the best thing to do is to accelerate at 1g for 10 light years and decelerate at 1g for the next ten.
Its not 66% of c unfortunately, its about 40% of c at maximum speed, where you will spend 33% of your time. The ship I described is also unfortunately not practical, it requires the mass production and safe storage of antimatter in ludicrous quantities. To get 100 kg of ship to this planet in 82 years would require 450 kg of anti matter, which even if we can do matter to energy conversion requires 4e19 joules of energy. This is the total energy produced by all earth sources (solar, tidal and geothermal) for 4 minutes. Which is quite a lot.
The problem is that although your true 'maximum' speed is C, you need to carry fuel to speed up, and by the standards of going really really fast even antimatter is pretty low energy density. Even without relativity think about it like this, each extra joule of energy you add speeds you up less than the one before did. To get close to C you need to not have to carry your fuel with you. Now, extrapolating from current tech we could perhaps build a giant space laser and use it to impel the ship remotely, but it would still need to be carrying 50% of the required antimatter to stop quickly.
(this is all aproximate, because mass of the ship changes continually as fuel is used, and that makes the equations hard to solve)
A possible ship design is an orion drive system which would be a TITANIC construction weighing millions of tonnes and carrying thousands upon thousands of nuclear bombs. It might be able to top out its speed at 0.1 c, since nuclear bombs are about 8% as good as antimatter explosions. So it would likely take more than 250 years or so to get there.
I'm not talking al dente spaghetti done either.
Like stick a fucking fork in her; we're done.
Shogun Streams Vidya
So far . . .
So ambitious for a species that hasn't even visited the planets in its own solar system . . .
The other planets are like Mississippi. Sure, you could go there if you wanted to, but why would you?
Any practical orion-type propulsion system for interstellar travel would use fusion reactions for power, probably initiated using powerful lasers. There's no reason to think it would go off on launch; and besides, there's no reason we have to launch it all at once.
I don't quite think the Moon is a necessary intermediate step, but if that's what it takes to get everyone on board, well, that's what it takes. So much of this is politics now, anyway. It's depressing.
How long would it take if we accelerated at 1g for half the voyage and then slowed back down over the second half (I'm assuming that speeds will stay low enough that force will still equal acceleration)?
I think we should concentrate more on the ISS. If we can build a spacedock, we can do whatever we want. And then we can make it into a giant ring and live there.
Of course, it's impossible to sustain an acceleration like that, because the energy cost increases toward infinity (which occurs at the speed of light).
And I don't have any idea what you mean by a "spacedock" (we've been docking things in space since Apollo), but making a giant ring would take far more material than we could conceivably heft into orbit using today's methods. It would be simpler to colonize Mars, not to mention more productive from a scientific standpoint. Mars is actually a much, much nicer place than LEO; it's just more distant.
Is there any way to calculate how long it would take w/ one g of force, then? Basically I want to know how long it would take if all artificial gravity was supplied by the engines.
I meant spacedrydock.
And the ring was just an allusion to Ringworld. That's a well known series, right?
Yes, I'm rather of the opinion that fuck the ISS right in its stupid ear with a space shuttle.
My understanding of relativity (I am not a physicist) indicates that the crew of the spacecraft would not perceive things in quite this manner, since the effects of time dilation would allow them to continue to perceive the same acceleration for an arbitrary period of time and at the same energy cost.
We'll BLAME! this shit up
In your frame of reference, everything seems totally normal. You feel whatever forces and accelerations would happen normally here on Earth. Your rate of time passage is quite different from what an observer on Earth would report, of course.
I think I see what you're asking, though, and the answer is "no". Once you've got yourself up to a really high velocity, it's just as hard (energy-intensive) to slow down as it was to get there in the first place (except that you're carrying less fuel, since you burned half of it on the way in—standard rocket equation stuff).
Yeah, ok. That makes sense.
I mean, yeah it blows chunks that it's so ridiculously far, but saying we should wait for warp is like looking at a canoe and saying we should wait for the Concord.
Edit: Or actually, like looking at a canoe and saying we should wait for a warp drive.