# We are not going to be doing any interstellar space travel **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [May 3, 2013, 9:08am UTC](https://boards.straightdope.com/t/we-are-not-going-to-be-doing-any-interstellar-space-travel/657398 "2013-05-03T09:08:43Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Peremensoe](https://avatars.discourse-cdn.com/v4/letter/p/ce7236/32.png) [@Peremensoe](https://boards.straightdope.com/u/Peremensoe)\ **Post date:** [May 3, 2013, 2:27pm UTC](https://boards.straightdope.com/t/we-are-not-going-to-be-doing-any-interstellar-space-travel/657398/21 "2013-05-03T14:27:52Z")
> [@snowthx](#): > > I see these arguments made sometimes, like it’s ‘manifest destiny’ to colonize Mars, or extend our species life span. [99%+ of life](http://www.endangeredspeciesinternational.org/overview.html) that ever lived on Earth have gone extinct. What makes us so special? Consciousness. Wonder. Art. We are the eyes of our world. Of course, none of this is likely very special on a galactic or universal scale. But just as each person should have dignity and value among billions, so should each world have value among the uncounted. I admit I may also have a certain bias. > [@](#): > > IMHO, our efforts and resources are better spend in solving earth-bound problems. Otherwise, we are likely to snuff ourselves out or soil our nest long before technology provides a life raft to some other place. You notice I mentioned “preserving our home world” as the _first_ of our species priorities. So, I agree–except that I don’t think the goals are exclusive or that the one must wait on the other. As suggested, some of the solutions for this planet may grow out of things we learn or achieve in the course of reaching for others. > [@billfish678](#): > > I think his other rants about his pizza delivery costumers explains the reason quite well 🙂 Ah yes. ---
**Author:** ![Don\_t\_Panic](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/don_t_panic/32/398_2.png) [@Don\_t\_Panic](https://boards.straightdope.com/u/Don_t_Panic)\ **Post date:** [May 3, 2013, 2:39pm UTC](https://boards.straightdope.com/t/we-are-not-going-to-be-doing-any-interstellar-space-travel/657398/22 "2013-05-03T14:39:48Z")
I don’t know. Unlike certain properly impossible things, such as time travel and me ever having sex again, interstellar space travel isn’t actually forbidden by the laws of physics. ---
**Author:** ![Askthepizzaguy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/askthepizzaguy/32/9405_2.png) [@Askthepizzaguy](https://boards.straightdope.com/u/Askthepizzaguy)\ **Post date:** [May 3, 2013, 2:47pm UTC](https://boards.straightdope.com/t/we-are-not-going-to-be-doing-any-interstellar-space-travel/657398/23 "2013-05-03T14:47:54Z")
> [@Der\_Trihs](#): > > Send several (for redundancy) lightweight, high speed probes to another star; upon arrival they use local materials to build a laser receiver and colonial/industrial infrastructure. Some time afterwards, a communications laser arrives encoded with the recorded mind states of a number of humans (or whatever); new brains and bodies are constructed and the minds downloaded into them. Off the top of my head there’s one scenario you didn’t cover. Wouldn’t need to cover it, because it’s **more absurd than just sending the human bodies to begin with.** The machines required to synthesize and gestate human cells and grow them into adult hood will take up more space and be a lot harder to create than just sending human women. That’s a lot simpler than sending a machine that can create a human woman- human women are \*\*\*already \*\*\*“machines” that can create more human beings. And do it a lot more easily and efficiently than any machine possibly could. If we’re going the \*redundancy \*route and we have mind beams and synthetic human bodies (clones), just send the human bodies. Assuming your mind beam technology existed, to “beam mind states” into a human body, that means it’s possible to clone human beings and also clone your thoughts as well. So you just do that, and put them aboard several redundant vessels. They’re clones, so who gives a damn. More than that, they’re your clones. You created them to try to travel to another star system. And if we’re doing that, you send a bunch of seeds and bacteria and all manner of other DNA aboard several payloads, and even livestock. Otherwise you’ve got to send machines which are capable of synthesizing from raw materials all the chemicals found inside of a cell, and then they’ve got to literally build a cell. And make sure that it develops into a life form. That requires more technology than just sending the human bodies and livestock. So your proposed solution doesn’t solve **any** problems associated with interstellar space travel that we didn’t already know how to solve using less sophisticated technology. _ **Building a human being** _ out of inorganic matter is a lot more complicated than just freezing and shipping it. And then you’re talking about building a laser beam and using it to hit a target in your other star system, which is moving. That’s one heck of a bulls-eye. But I’ll assume for the moment that we can do this. It’s one thing to have any light whatsoever be received via a laser pulse, it’s quite another to send the amount of data contained within a human brain via a series of laser pulses. Nothing can interrupt this laser beam, or parts of your “mind” will be missing upon arrival. So we can’t have, for example, one of those trans-neptunian objects moving across your beam. You can’t have your clones forgetting how read or comprehend language. But again,\*\* this doesn’t solve any problem that we already know how to get around\*\*. You’d just send clones or really brave non-clone people, and send lots of them. The issue isn’t that _I’m afraid we will lose some people on the way there_, the issue is that \*it will take too long at safe speeds. \*Unsafe speeds will destroy every single one of your spermatozooan seed craft due to the interstellar medium, so you must travel slow enough to move through the medium. > [@](#): > > Not at all. At astronomical distances it takes only a tiny nudge to miss an object. The last thing you would want is to turn at right angles like an ocean going vessel anyway; you’d be giving up all your forward velocity. If you’re traveling at a significant percentage of the speed of light, how do you detect what you’re about to run into in time? Further, you’ll be running into matter all the time. You’re not going to be dodging dust or debris fields the entire way, and you can’t really avoid hitting gas. > [@](#): > > That’s a serious exaggeration. Do you know of any materials which can withstand matter being hurled at it, at near light speed? How we study the insides of atoms is by hurling matter at itself at significant portions of the speed of light. And that splits atoms apart. There’s no construction process that builds molecules which can survive such an impact, let alone things as large as spacecraft. It’s an exaggeration if we’re not attempting to travel at light speed or anywhere close to it. But to traverse those distances, we’ve got to try. > **[EarthSky | New solar sail may travel to Alpha Centauri](https://earthsky.org/space/alpha-centauri-travel-time/)** > > The distances between stars are vast, which is why star travel is so far. But now, a new solar sail may be able to travel to Alpha Centauri in 20 years. [QUOTE=earthsky] _So how could we get to Alpha Centauri? Would a conventional rocket work? Consider the Space Shuttle, which traveled only a few hundred kilometers into space. If Earth were the size of a sand grain, this would be about the width of a hair in contrast to the 10 kilometers to Alpha Centauri. You’d need about 10,000 shuttle main engines in sequence just to build up a decent speed (say, 1/100th light speed). The Space Shuttles weren’t starships. **At a maximum speed of about 17,600 mph (about 28,300 kph), it would have taken a Space Shuttle about 165,000 years to reach Alpha Centauri.**_ [/QUOTE] Going a whole lot faster than 17,600 miles per hour isn’t really advisable. A cloud of asteroidal debris can ruin your entire day. > [@](#): > > Why? If you’re going slow, build big; big enough to hold a town’s worth of people. Have the thing travel between those comets and rogue planets, harvesting useful materials as it goes so it never runs out of fuel and supplies. Well, that will certainly make the trip **even longer.** I’m already assuming we can construct the ships that can do this in the first place. So we do that here on Earth, where we have the population and resources and don’t have to worry about stopping and starting. We just build ship after ship. That’s assuming we have the will to do this and the ability. There’s enough matter here in the solar system to easily construct fleets of ships. Well, easier than a ship that’s supposed to be traveling to another star system could possibly do. So here, you’ve solved none of the problems I’ve described. You’ve just created additional problems of starting and stopping and building things along the way, which were never necessary problems to add to our discussion, especially since it solves nothing. > [@](#): > > Every so often it stops by a large chunk of interstellar debris, builds another ship out of it and moves half its population there. Keep this up for long enough and interstellar space will be filled with an ever expanding cloud of these ships traveling in all directions. So instead of the “quick” 165,000 year journey, we might get put aboard a different vessel heading for an even more distant star system, another 200,000 years away. Again, we can \*\*\*already \*\*\*build a fleet of ships heading in all directions, here in our home star system where it would be a lot simpler and feasible. The issue is not creating the ships, the issue is getting to a destination. > [@](#): > > No, if we ever do colonize this system there’s no reason to think that the colonies would be dependent on the homeworld. Especially since preventing such a extinction scenario is one of the major reasons to colonize space in the first place. If we are content to colonize only this star system, that’s fine. But then all we’re talking about is, for example, a Mars colony. So this **ignores the question** of why do we want to colonize interstellar space in the first place. If we’re going to ignore the question, then we aren’t really solving the problem of interstellar space travel, now are we? Creating solutions to problems we already know how to solve more efficiently (and additional problems on top of that) doesn’t help matters any. All you did was ignore the question or make the problem more complicated with your responses. Which is fine, if that’s the route you want to go. I’m looking for less complicated, more efficient, actual solutions which don’t ignore the problem. ---
**Author:** ![chargerrich](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chargerrich/32/5399_2.png) [@chargerrich](https://boards.straightdope.com/u/chargerrich)\ **Post date:** [May 3, 2013, 2:53pm UTC](https://boards.straightdope.com/t/we-are-not-going-to-be-doing-any-interstellar-space-travel/657398/24 "2013-05-03T14:53:53Z")
The only counter (and hope) that I can offer is the following, taking into account we are talking about a scale of tens or even hundreds of thousands of years from now. That being stated, consider the following: 1. Around 2000 years ago, our civilization believed the world might be flat (Eratosthenes is generally credited with discovering the curvature of our planet around 200 BC) 2. 800 years ago our civilization was just discovering the science of navigation and true north with little ability to do more than coastal sailing. 3. Just 200 years ago the idea of Earth based flight by man and machine was ludicrous (with apologies to Leonardo!). 4. A mere 100 years ago, the moon and other planets might as well have been as far from our reach as the [Abell 1835](http://en.wikipedia.org/wiki/Galaxy_Abell_1835_IR1916) galaxy (which is over 13 Billion light years away) In just the last 60 years we have accumulated exponentially more science, discovery and innovation than the previous millions of years that make up the entirety of our existence combined. So it stands to reason that their are concepts and technologies completely foreign to us which would make interstellar travel possible 500-5000 years from now (surely closer to the latter I agree). The smartest minds on the planet have consistently missed - by a wide margin - on any form of prediction and technology seems to be advancing at an ever increasing rate. Are we certain that 1000 years from now, even Einstein wont be proven wrong on some level or that some unimagined technology could make the impossible, possible? ---
**Author:** ![robert\_columbia](https://avatars.discourse-cdn.com/v4/letter/r/e79b87/32.png) [@robert\_columbia](https://boards.straightdope.com/u/robert_columbia)\ **Post date:** [May 3, 2013, 2:55pm UTC](https://boards.straightdope.com/t/we-are-not-going-to-be-doing-any-interstellar-space-travel/657398/25 "2013-05-03T14:55:32Z")
Dude, generation ship. ---
**Author:** ![Jman](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jman/32/4416_2.png) [@Jman](https://boards.straightdope.com/u/Jman)\ **Post date:** [May 3, 2013, 3:00pm UTC](https://boards.straightdope.com/t/we-are-not-going-to-be-doing-any-interstellar-space-travel/657398/26 "2013-05-03T15:00:03Z")
> [@Der\_Trihs](#): > > Personally, I predict that in a few centuries at most there won’t be a significant amount of what we would call humans _anywhere_, in or out of this system. In what way of speaking? Are you talking about a nuclear annihilation? If so, then, well, it’s certainly possible we’ll wipe out a very large chunk of humanity…though I’d imagine there would still be a fair few left. Maybe we’ll cause our own extinction in a few centuries. Definitely a possibility. However, excepting that… If you aren’t talking about nuclear annihilation, how do you figure? Evolution doesn’t happen that fast. We’ve been anatomically modern in our current form for around 200,000 years, and the genus is around 2.4 million years old. ---
**Author:** ![WordMan](https://avatars.discourse-cdn.com/v4/letter/w/e8c25b/32.png) [@WordMan](https://boards.straightdope.com/u/WordMan)\ **Post date:** [May 3, 2013, 3:01pm UTC](https://boards.straightdope.com/t/we-are-not-going-to-be-doing-any-interstellar-space-travel/657398/27 "2013-05-03T15:01:09Z")
I am quite willing to accept the premise of the OP given what we know today. But humans have regularly demonstrated: a) An inability to anticipate what we may discover b) An inability to understand how that will evolve our understanding of the world/universe/reality around us - and what is possible in terms of tools we could then produce. Or, a different way to ask the question - how big is the distance between the tech of 1,000 years ago vs. the tech of today VERSUS the tech of today vs. what we might be capable of 1,000 years from now (if we and the Earth are still around)? Personally, I wouldn’t bet against another Newton/Einstein level revelation or two along with the way. How many Einsteins are we away from coming at the space-travel challenge in a very different way we look at it now? ---
**Author:** ![Askthepizzaguy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/askthepizzaguy/32/9405_2.png) [@Askthepizzaguy](https://boards.straightdope.com/u/Askthepizzaguy)\ **Post date:** [May 3, 2013, 3:01pm UTC](https://boards.straightdope.com/t/we-are-not-going-to-be-doing-any-interstellar-space-travel/657398/28 "2013-05-03T15:01:29Z")
> [@Peremensoe](#): > > I didn’t see any comment on sublight voyages other than generation and sleeper ships. What about digitized minds, robots, and stored DNA? We don’t have to transport whole people across the gulfs; we build them on arrival, or we don’t bother with old-style biological bodies at all. So send out as many relatively-small probes as we can build, and accept that some fraction will go awry or be destroyed. Already commented. If you can send the robots, you can obviously send the clones as well. It would be much simpler and take up less space, and requires less advanced technology. Over-complicating the problem isn’t necessary, since the problem is already complicated. > [@](#): > > As for the predicted demise of humanity within 100,000 years: quite possible. But shouldn’t we _try_ to avoid that? Sure. One solution would be to ensure that we colonize other star systems. > [@](#): > > Preserving our home world (as long as the sun remains amenable) _and_ reaching out as far into space as we can manage–these seem like they should be fundamental species motives. I concur, this is why I try to reduce the size of the problem, not create new and unnecessary ones. If you’re just going to send robots and computers, with the intent to create the people when you get there, you might as well freeze the people and send them too. I guarantee you that livestock and seeds and stored food reserves and actual people will be easier to turn into a colony than manufacturing one cell at a time and trying to build a human colony from that. The issue is getting there in the first place. So we’re talking about firing sperm into space (a large number of redundant spacecraft) at very slow speeds (we’re talking hundreds of thousands of years to destination) which was my entire point. We’re not going to be doing that, because it’s prohibitively expensive and the duration is longer than 100,000 years. I mean, if you’re going to go that slowly, you might as well put a message in a bottle and literally hurl it to the next star system. Never mind with all this technology nonsense. Just send out a bunch of probes filled with bacteria and shit, and hope it crashes into a planet sometime in the far future. Make panspermia a reality. If you’re going to replicate people using Star Trek replicator technology, then all you send is a computer with a database containing detailed files on DNA, a sensor array that detects star systems and knows how to navigate, and you send a replicator, and you build a billion of these things, and you send them at cruising speeds of 10,000 miles per hour in all directions, and hope that a few of them survive the journey and crash into alien planets. > [@](#): > > _Why do you hate humanity_, **pizza man**?? Well, mostly because of the kind of nonsense that causes people to murder other people in the name of their imaginary friend. And the folks that don’t tip. I’d be willing to freeze them and send them out as probes. They’re useless to us down on Earth anyway. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [May 3, 2013, 3:11pm UTC](https://boards.straightdope.com/t/we-are-not-going-to-be-doing-any-interstellar-space-travel/657398/29 "2013-05-03T15:11:50Z")
Why would we not know anything about the local conditions before we got there? That’d be awfully silly of us, to go to all that effort to send a ship there without even looking to see what the conditions are, first. We’re already pretty close to having the technology to detect life around other stars, certainly much closer than we are to being able to build a starship. And yes, according to everything we know (or think we know) about physics, the trip would take a very long time. Or at least, a very long time compared to our individual lifespans. But it’s still a blink of an eye compared to geologic timescales. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [May 3, 2013, 3:15pm UTC](https://boards.straightdope.com/t/we-are-not-going-to-be-doing-any-interstellar-space-travel/657398/30 "2013-05-03T15:15:31Z")
Oh, and stop worrying about interstellar debris. For all practical purposes, there isn’t any such thing. Even in our relatively dense solar system, and even in the asteroid belt, one of the densest regions of our solar system, do you know how our space probes avoid hitting anything? They just ignore the asteroids entirely, and trust that they won’t be so incredibly unlucky as to hit something. ---
**Author:** ![Peremensoe](https://avatars.discourse-cdn.com/v4/letter/p/ce7236/32.png) [@Peremensoe](https://boards.straightdope.com/u/Peremensoe)\ **Post date:** [May 3, 2013, 3:18pm UTC](https://boards.straightdope.com/t/we-are-not-going-to-be-doing-any-interstellar-space-travel/657398/31 "2013-05-03T15:18:42Z")
I disagree that machines to build people are no easier to transport than people. You don’t need a woman, you just need a ‘womb’ and gametes. The tricky part is the mechanisms to support the infants and children. That’s why assembling ‘adult’ bodies from non-organic materials on site might be most practical. Specialized robots to do this can certainly be smaller and simpler than the general-purpose bodies they build. Then download the stored minds. _Then_ cultivate the bio-babies, if we’re still attached to flesh as part of authentically human identity. ETA: I would say that the murderers and bad tippers should be _ineligible_ for either the cold-transport or the encoding. We may not want them here, but it would be worse to make them our legacy to the stars. ---
**Author:** ![Grrr](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/grrr/32/146_2.png) [@Grrr](https://boards.straightdope.com/u/Grrr)\ **Post date:** [May 3, 2013, 3:18pm UTC](https://boards.straightdope.com/t/we-are-not-going-to-be-doing-any-interstellar-space-travel/657398/32 "2013-05-03T15:18:46Z")
> [@chargerrich](#): > > The only counter (and hope) that I can offer is the following, taking into account we are talking about a scale of tens or even hundreds of thousands of years from now. > > That being stated, consider the following: > > 1. Around 2000 years ago, our civilization believed the world might be flat (Eratosthenes is generally credited with discovering the curvature of our planet around 200 BC) > > 2. 800 years ago our civilization was just discovering the science of navigation and true north with little ability to do more than coastal sailing. > > 3. Just 200 years ago the idea of Earth based flight by man and machine was ludicrous (with apologies to Leonardo!). > > 4. A mere 100 years ago, the moon and other planets might as well have been as far from our reach as the [Abell 1835](http://en.wikipedia.org/wiki/Galaxy_Abell_1835_IR1916) galaxy (which is over 13 Billion light years away) > > In just the last 60 years we have accumulated exponentially more science, discovery and innovation than the previous millions of years that make up the entirety of our existence combined. So it stands to reason that their are concepts and technologies completely foreign to us which would make interstellar travel possible 500-5000 years from now (surely closer to the latter I agree). > > The smartest minds on the planet have consistently missed - by a wide margin - on any form of prediction and technology seems to be advancing at an ever increasing rate. Are we certain that 1000 years from now, even Einstein wont be proven wrong on some level or that some unimagined technology could make the impossible, possible? Thank you. I came to post exactly this. Imagine 500 years ago if I told someone that I could take a device the size of the palm of my hand and talk to someone half way across the planet. I would get laughed at. ---
**Author:** ![Askthepizzaguy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/askthepizzaguy/32/9405_2.png) [@Askthepizzaguy](https://boards.straightdope.com/u/Askthepizzaguy)\ **Post date:** [May 3, 2013, 3:23pm UTC](https://boards.straightdope.com/t/we-are-not-going-to-be-doing-any-interstellar-space-travel/657398/33 "2013-05-03T15:23:40Z")
> [@Lumpy](#): > > Over-pessimistic on several fronts: > > 1. You don’t need an artificial black hole to create a warp drive, and the energy requirements might not be as bad as first thought. There are already proposals for laboratory experiments to detect whether a warp effect can actually be created, although no one is proposing that a Zephram Cochrane will appear in our lifetimes It’s overly pessimistic because _we don’t even know if we can create a warp effect yet?_ > [@](#): > > 1. The Oort Cloud is not a boulder-strewn rubble field like the Millennium Falcon went through. I’m aware. You don’t need to weave through asteroids. You do need to be lucky enough to avoid hitting \*dust \*at certain speeds. > [@](#): > > The bodies in it are estimated to be separated by distances comparable to the width of our solar system. Gas and dust are an acknowledged problem, and most proposals for fast interstellar flight presume some sort of system for clearing the way- lasers, or magnetic shields, or expendable drones. I like the drones idea. The drone smashes into things and creates another debris field to fly through. Magnetic shields, splendid. I’m not sure how much magnetic field energy would be required to repel the matter that would be hitting your ship, but this is certainly feasible at slower speeds anyway. The issue is that your magnetic field will be moving as fast as your ship is, and therefore, the issue becomes one of time.At relativistic speeds,the magnetic field will not exert enough force on the objects in your path to move them out of the way in time. If we ignore traveling at relativistic speeds then we don’t really need the magnetic shields anyway. It doesn’t solve any problems that maneuvering thrusters wouldn’t solve. The laser idea seems plausible. So I give you much kudos for that. The issue being that something traveling laterally may not hit the laser beam, just collide with the ship. And the wider the beam, the less powerful it is. You wouldn’t be able to obliterate an asteroid in our path. You still have to turn to avoid it, which you don’t want to do at relativistic speeds. > [@](#): > > 1. No one proposes a 100,000 year journey; 1% of the speed of light would get you to the nearest solar systems in about 500 years, 5% within 100 years. If you’re going to be moving at 1% of the speed of light, that’s 6 million miles per hour. There’s not much difference in terms of danger if you went faster than that. There’s nothing that I’ve described which is any more or less dangerous at 6 million miles per hour and 600 million. You might as well approach light speed if you can move that even 1% that fast safely. > [@](#): > > 1. If we’ve learned to live in our solar system beyond Earth, we don’t need a viable ecosystem waiting for us at our destination. See above about keeping people alive and well in habitats. Interstellar colonization isn’t going to be a Heinleinesque “Farmer in the Sky” scenario of neo-pioneers building log cabins and plowing the new land. I agree that building the new colony isn’t as difficult a task as moving near light speed. However, we still need to build it, because the entire point of populating a new star system is so that we don’t need to live inside the interstellar ship forever. So it’s not as simple as handwaving away the difficulty in making the new colony. We still have to make it, or we’ve traveled several light years to float outside of a planet we never intended to colonize, which is ridiculous in the extreme. ---
**Author:** ![Askthepizzaguy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/askthepizzaguy/32/9405_2.png) [@Askthepizzaguy](https://boards.straightdope.com/u/Askthepizzaguy)\ **Post date:** [May 3, 2013, 3:26pm UTC](https://boards.straightdope.com/t/we-are-not-going-to-be-doing-any-interstellar-space-travel/657398/34 "2013-05-03T15:26:58Z")
> [@Chronos](#): > > Oh, and stop worrying about interstellar debris. For all practical purposes, there isn’t any such thing. Even in our relatively dense solar system, and even in the asteroid belt, one of the densest regions of our solar system, do you know how our space probes avoid hitting anything? They just ignore the asteroids entirely, and trust that they won’t be so incredibly unlucky as to hit something. LOL I don’t want to be on the interstellar craft designed by this guy. Reputable scientists all agree the matter in between the stars is, in fact, a problem. Being ignorant of the problem isn’t a solution to it. ---
**Author:** ![Muffin](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/muffin/32/4341_2.png) [@Muffin](https://boards.straightdope.com/u/Muffin)\ **Post date:** [May 3, 2013, 3:29pm UTC](https://boards.straightdope.com/t/we-are-not-going-to-be-doing-any-interstellar-space-travel/657398/35 "2013-05-03T15:29:41Z")
Anyone know what the theoretical distance limitations on qubit information transfer are? ---
**Author:** ![Askthepizzaguy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/askthepizzaguy/32/9405_2.png) [@Askthepizzaguy](https://boards.straightdope.com/u/Askthepizzaguy)\ **Post date:** [May 3, 2013, 3:33pm UTC](https://boards.straightdope.com/t/we-are-not-going-to-be-doing-any-interstellar-space-travel/657398/36 "2013-05-03T15:33:50Z")
> [@Peremensoe](#): > > I disagree that machines to build people are no easier to transport than people. You don’t need a woman, you just need a ‘womb’ and gametes. The tricky part is the mechanisms to support the infants and children. That’s why assembling ‘adult’ bodies from non-organic materials on site might be most practical. Okay, we’ll agree to disagree. In the meantime, we \*have \*human women, and they \*can \*make more people already. When we invent the technology your fiction requires, then we can measure its size, and then our debate will be over. I still betcha a human woman will be smaller than such technology, and easier to make. For example, I can make a human woman just by fuckin’ one. > [@](#): > > Specialized robots to do this can certainly be smaller and simpler than the general-purpose bodies they build. Then download the stored minds. _Then_ cultivate the bio-babies, if we’re still attached to flesh as part of authentically human identity. Keeping in mind this does nothing to address the problem of getting there in the first place, and that we already know how to make human bodies without need of such technology, and that it adds complicated steps to an already complicated problem, and that it won’t affect the travel time in the slightest, sure. I just want to return to my main premise, which is that we’re trying to make the problem easier to solve, and the number of problems involved to be a smaller number, and the number of years required to be fewer. Increasing the number of problems without solving any of them doesn’t help. > [@](#): > > ETA: I would say that the murderers and bad tippers should be _ineligible_ for either the cold-transport or the encoding. We may not want them here, but it would be worse to make them our legacy to the stars. Whatever happened to the Christian concept of redemption and forgiveness? 😛 Give them a few thousand years to think about what they’ve done, I say. 😃 ---
**Author:** ![Muffin](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/muffin/32/4341_2.png) [@Muffin](https://boards.straightdope.com/u/Muffin)\ **Post date:** [May 3, 2013, 3:35pm UTC](https://boards.straightdope.com/t/we-are-not-going-to-be-doing-any-interstellar-space-travel/657398/37 "2013-05-03T15:35:12Z")
> [@Askthepizzaguy](#): > > LOL > > I don’t want to be on the interstellar craft designed by this guy. [I like this design.](http://www.livinglocurto.com/wp-content/uploads/2010/06/pizza.jpg) ---
**Author:** ![Colophon](https://avatars.discourse-cdn.com/v4/letter/c/f05b48/32.png) [@Colophon](https://boards.straightdope.com/u/Colophon)\ **Post date:** [May 3, 2013, 3:37pm UTC](https://boards.straightdope.com/t/we-are-not-going-to-be-doing-any-interstellar-space-travel/657398/38 "2013-05-03T15:37:29Z")
> [@Peremensoe](#): > > I’m not aware that NASA relies on the notion of interstellar travel for any funding; they have a hard enough time getting funding for interplanetary work. Yeah, this. Since when has Nasa been in the business of promising interstellar jaunts? Even getting a manned Mars mission off the ground is pretty hard going. ---
**Author:** ![Askthepizzaguy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/askthepizzaguy/32/9405_2.png) [@Askthepizzaguy](https://boards.straightdope.com/u/Askthepizzaguy)\ **Post date:** [May 3, 2013, 3:50pm UTC](https://boards.straightdope.com/t/we-are-not-going-to-be-doing-any-interstellar-space-travel/657398/39 "2013-05-03T15:50:25Z")
> [@WordMan](#): > > I am quite willing to accept the premise of the OP given what we know today. > > But humans have regularly demonstrated: > a) An inability to anticipate what we may discover > b) An inability to understand how that will evolve our understanding of the world/universe/reality around us - and what is possible in terms of tools we could then produce. > > Or, a different way to ask the question - how big is the distance between the tech of 1,000 years ago vs. the tech of today VERSUS the tech of today vs. what we might be capable of 1,000 years from now (if we and the Earth are still around)? > > Personally, I wouldn’t bet against another Newton/Einstein level revelation or two along with the way. How many Einsteins are we away from coming at the space-travel challenge in a very different way we look at it now? I can accept this idea as a _concept_. The issue is that you still need to get there, and no amount of technological advancement avoids the problem of getting there, and getting there means moving at some speed, for some length of time. At certain speeds, the matter you’re sending is in real danger of being damaged or destroyed by the medium you’re moving in. What is the theoretical limit for moving through ocean water, for example? You could construct the craft out of exotic molecules, and it will still be made out of atoms, yes? How fast can those atoms move through water before they no longer resemble the craft you built? There’s a hard, physical limit you’re running into. And generating shields to push the water out of the way still requires energy, and a lot of it, to move matter in such a way, and at such speeds. And there’s a limit to how much energy you’ll extract from matter, because that involves cosmological constants. We’re not going to extract from a neutron more energy than is contained within the neutron. We can’t conjure matter and energy like magic. We live in a physical universe and we are bound by its laws. Math is not something we can avoid with pretending. We have to find a way to make the math work. The amount of energy required to move a few atoms of water out of your way, if you’re traveling near the speed of light, is immense, because you’ve got to either project energy/forces very far away from your ship (to the tune of a few million miles) or you’ve got to accelerate that matter very quickly, which adds to the energy cost. And the problem of getting there slowly is that it takes too long. Even our nearest stellar neighbors would take hundreds of thousands of years traveling at speeds wherein we could maneuver out of the way of debris larger than a grain of sand. Then, it’s got to be a star system worth getting to. Imagine we travel to Proxima Centauri and find that there’s a gas giant there and nothing else. Well of course we find out before we travel. But _finding out_ doesn’t change whether there is a habitable (for even loose definitions of habitable) globe to colonize. There either is or there is not. And if there is not, that means you have to travel to a different, and more distant, star system. Which adds to the travel time. Given my prediction that this wouldn’t happen within 100,000 years, taking more than that length of time to get to another star system satisfies the requirements of my prediction. If you want to get there faster, you have to figure out how, and you don’t do that by either ignoring the problem, or imagining ways to make the problem more complicated. Agreed, you could build a probe that can assemble matter out of energy. That’s possible. It still needs to get there in one piece. How long will it take? That’s the challenge. **If it takes too long, then just send in the clones. You haven’t saved me any time. I want to do this before 100,000 years have passed. Tell me how.** Then tell NASA how, because they don’t know either. ---
**Author:** ![Askthepizzaguy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/askthepizzaguy/32/9405_2.png) [@Askthepizzaguy](https://boards.straightdope.com/u/Askthepizzaguy)\ **Post date:** [May 3, 2013, 4:00pm UTC](https://boards.straightdope.com/t/we-are-not-going-to-be-doing-any-interstellar-space-travel/657398/40 "2013-05-03T16:00:22Z")
> [@Colophon](#): > > Yeah, this. > > Since when has Nasa been in the business of promising interstellar jaunts? Even getting a manned Mars mission off the ground is pretty hard going. Well, I hear folks like Neil Degrasse Tyson and all sorts of physicists and astronomers and scientists of all stripes tell us that the reason we’re funding NASA isn’t just to collect data, but to spread humanity throughout the stars. We already have probes collecting data. So why fund manned missions to anything? Why colonize Mars? If you really want to assure humanity’s future, you have to escape the Sol system. We already have the technology to colonize Mars. It’s just prohibitively expensive. So you watch the science channels and discovery channels and you hear all these scientists talk about looking beyond, and ensuring humanity’s long term survival, and all this, and they build up our interest by talking about possibly needing light-speed travel, and that’s all well and good to keep the public interested in space. But if you want to make good on those promises, you need a method of getting there. And to me, 100 thousand years is a ludicrous amount of time to wait. We might as well strap people to the next Voyager-style probe for all the good that does. So talk about the technology that allows us to do this faster. All I see so far is folks ignoring the problem, adding to the travel time, or requiring technology we don’t have to do things we already know how to do. I already know how to make the problem _worse_. You don’t win the Nobel Prize for that kind of an idea. We’re not trying to make the problem worse, we’re trying to solve the problem or make it less daunting. [Previous page](https://boards.straightdope.com/t/we-are-not-going-to-be-doing-any-interstellar-space-travel/657398.md?page=1) [Next page](https://boards.straightdope.com/t/we-are-not-going-to-be-doing-any-interstellar-space-travel/657398.md?page=3)