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Sizing Up the Daedalus Interstellar Spacecraft

CmdrTaco posted more than 3 years ago | from the oh-this-will-be-fine dept.

Sci-Fi 191

astroengine writes "How big would an interstellar spaceship need to be? New artwork of the British Interplanetary Society's 1970's Project Daedalus by the non-profit organization Tau Zero Foundation gives the impression that the fuel economy for a nuclear pulse propelled vehicle might be a bit steep."

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Space and Sails (1)

h00manist (800926) | more than 3 years ago | (#35007050)

Space seems like the ultimate research and application ground for something that uses the environment around it as a power source, inspired by sails.

Re:Space and Sails (1)

danhuby (759002) | more than 3 years ago | (#35007064)

Such as?

Re:Space and Sails (1)

lxs (131946) | more than 3 years ago | (#35007296)

Except that interstellar space isn't much of an exploitable environment, being mostly dark and empty.

Re:Space and Sails (1)

sznupi (719324) | more than 3 years ago | (#35008028)

...seems like a good place for basement-dwelling kind slasher movie.

Re:Space and Sails (3, Insightful)

Lumpy (12016) | more than 3 years ago | (#35007304)

So then what do you do when you pass the heilopause and you no longer have a solar "wind"?

Honestly a redesign using ion engines of today would make a different craft. Plus it would allow the craft to not just speed on by in a ballistic trajectory, but even start breaking and enter a orbit that would allow the craft to stay and radio back info.

It can be electrically powered by Nuclear reactors, and as each one get's past it's 20 year lifespan you jettison it making the craft lighter. Ion engines already are producing impressive thrust for the age of the technology. An unmanned interstellar probe moving at 12% the speed of light, assuming it does not plow into something out there is a very feasible project and could gather scientific data the entire way. Although the Doppler effect on communications would be interesting. But research into really measuring time dilation could be done as well.

Sadly, we are far more interested in killing each other. It's more important to fund the war machine than the thinking machine.

Re:Space and Sails (1)

FTWinston (1332785) | more than 3 years ago | (#35007838)

An unmanned interstellar probe moving at 12% the speed of light ... Although the Doppler effect on communications would be interesting.

"Interesting" is a gross overstatement here. Even if you didn't know how fast it was going, such a Dopper shift would be trivial to correct for with a suitable signal. Now, if we're talking 99.999% c, that's another matter!

Re:Space and Sails (2)

sznupi (719324) | more than 3 years ago | (#35008012)

You coast until getting into the heliosphere of another star (they move quite predictably) - you can even slow down like that! (with the help of stellar aerobraking? That would be some sight...)

Sails (also of more active kind [wikipedia.org] ) probably have one monumental advantage: they should be fairly easily mass-produced (without swallowing half of GDP of the planet like TFA projects would / that's some solution to constant (it was pretty much always like that, don't kid yourself it will ever change much) lack of funds for research)

Re:Space and Sails (1)

Vectormatic (1759674) | more than 3 years ago | (#35008858)

You coast until getting into the heliosphere of another star (they move quite predictably) - you can even slow down like that! (with the help of stellar aerobraking? That would be some sight...)

the problem with stellar aerobreaking is that if you want to come to a full stop again, the target star needs pretty much the exact same heliosphere as your origin for it to work effectively. Traveling to a star which has only half the solar wind pressure would require you to close your solar screen at the start of the journey because else you will be going to fast to bleed off all the speed. This off course means you will be traveling much slower.

Your speed is basically limited by the weakest star in your journey

Re:Space and Sails (1)

sznupi (719324) | more than 3 years ago | (#35009120)

Not really, no - first, the probe can initially put itself into a very elliptical orbit around target star and circularize it gradually (like we already do when arriving at other local planets, with probes having pitiful delta-v budgets); parameters of its orbit don't need to mirror at all those at the start of journey...

Secondly, when I wrote "stellar aerobraking" - I didn't mean using only stellar wind, in the same way as during departure. Actual plunge into relatively dense portions of the stellar atmosphere could bleed off some km/s ... yes, expected to hard, but certainly "that would be some sight..." ;>
Some gas giant might be similarly handy. Or - having some "last ditch" means of active propulsion (a nuclear warhead or two?) - to be used also when extremely close to the target star, exploiting Oberth effect.

Re:Space and Sails (0)

Anonymous Coward | more than 3 years ago | (#35009460)

First habitable planet outside our Solar System located! in other news.... Kepler XV uninhabitable due to nuclear fallout from space probe.

Re:Space and Sails (1)

pixelpusher220 (529617) | more than 3 years ago | (#35009508)

You don't sail much do you?

You could, you know, trim your sails or deploy more sail depending on the current (solar) wind...

Re:Space and Sails (1)

Vectormatic (1759674) | more than 3 years ago | (#35009602)

yes, but assuming you want to go somewhere in a cosmic space, you would always be on full sail, except when limited, by say, your breaking ability at the other end...

Re:Space and Sails (1)

amorsen (7485) | more than 3 years ago | (#35008138)

So then what do you do when you pass the heilopause and you no longer have a solar "wind"?

Solar sails don't run on the solar wind, they run on photon pressure. Not that it helps much; it will be difficult to get much thrust from solar sails when you are at the heliopause, simply because the Sun will be awfully dim from that distance.

Re:Space and Sails (2)

Chrisq (894406) | more than 3 years ago | (#35008172)

So then what do you do when you pass the heilopause and you no longer have a solar "wind"?

I half remember some proposal where a sail plane would spend decades in ever increasing elliptical orbits building up speed until it would change course and head off at some reasonable percentage of the speed of light.

Re:Space and Sails (1)

mangu (126918) | more than 3 years ago | (#35008828)

I half remember some proposal where a sail plane would spend decades in ever increasing elliptical orbits building up speed until it would change course and head off at some reasonable percentage of the speed of light.

That's not possible because escape velocity from the solar system is well below that. If you move at a reasonable percentage of the speed of light, your trajectory is straight, not elliptical. Or rather, it's an ellipse that's so elongated it goes beyond the heliopause.

Re:Space and Sails (1)

Kell Bengal (711123) | more than 3 years ago | (#35009346)

Not quite true - as your orbital radius increases, your velocity decreases or else you have a hyperbolic trajectory and aren't 'orbiting' per se.

Re:Space and Sails (1)

nospam007 (722110) | more than 3 years ago | (#35009118)

"So then what do you do when you pass the heilopause and you no longer have a solar "wind"?"

Lasers!

HOW DO I VIEW ALL COMMENTS WITH NEW SLASHDOT? (-1)

Anonymous Coward | more than 3 years ago | (#35007368)

I apologize profusely for barging in like this, but I need your help. When there are more than 50 comments to a story, how do I view all of them using this shitty new Slashdot UI? I have the slider all the way to -1, but I can't see more than 50 comments! Please, can anyone help me with this?

Re:HOW DO I VIEW ALL COMMENTS WITH NEW SLASHDOT? (0)

hellop2 (1271166) | more than 3 years ago | (#35007434)

You scroll all the way to the bottom and click "Get X More Comments".

Re:Space and Sails (2)

Seumas (6865) | more than 3 years ago | (#35008032)

We can't even coax ourselves into going back to the moon. At this point, we might as well be contemplating inter-dimensional travel, for all it matters.

Spaceship? (3, Insightful)

stjobe (78285) | more than 3 years ago | (#35007052)

Wouldn't "space probe" be more accurate? I don't believe it was ever intended to be manned.

Re:Spaceship? (2)

Z00L00K (682162) | more than 3 years ago | (#35007276)

And if it were to be manned it wouldn't be a return trip so to allow for a sufficient genetic variation the crew needs to be at least 1600 individuals.

Otherwise the risk of genetic degradation would be too great.

Re:Spaceship? (5, Funny)

geogob (569250) | more than 3 years ago | (#35007334)

But... I was told that 2 was enough?!

Re:Spaceship? (1)

bronney (638318) | more than 3 years ago | (#35007380)

insta +1 :)

Re:Spaceship? (0)

Anonymous Coward | more than 3 years ago | (#35007736)

yeah. me and yo momma.

Re:Spaceship? (2, Interesting)

Anonymous Coward | more than 3 years ago | (#35007356)

Or you could start with a small female crew, and thousands of "genetic samples". (Semen and eggs)

Re:Spaceship? (1)

AGMW (594303) | more than 3 years ago | (#35009416)

Or you could start with a small female crew, and thousands of "genetic samples". (Semen and eggs)

Why only chose the small females? Is that to save space or just weight?

Re:Spaceship? (0)

Anonymous Coward | more than 3 years ago | (#35007762)

The male/female ratio don't need to be 1/1

Re:Spaceship? (0)

Anonymous Coward | more than 3 years ago | (#35008906)

Doctor, you mentioned the ratio of ten women to each man. Now, wouldn't that necessitate the abandonment of the so-called monogamous sexual relationship, I mean, as far as men were concerned?

Regrettably, yes. But it is, you know, a sacrifice required for the future of the human race. I hasten to add that since each man will be required to do prodigious... service along these lines, the women will have to be selected for their sexual characteristics which will have to be of a highly stimulating nature.

Re:Spaceship? (1)

Manfred Maccx (1365933) | more than 3 years ago | (#35009570)

Could you please send me an application form.

Re:Spaceship? (1)

sznupi (719324) | more than 3 years ago | (#35007872)

http://en.wikipedia.org/wiki/Embryo_space_colonization [wikipedia.org]
...if we'll ever do direct flights, that seems like the most likely way (yes, we can already put humans into deep hibernation!)

Though I suspect it might be just gradual spreading across Oort cloud (estimated trillion comets!) over several thousands of years ... and at one point some groups will hitch a ride into the Oort cloud of some passing star. On geological timescales this will also assure very quick colonization of the galaxy.

Re:Spaceship? (1)

snap2grid (630315) | more than 3 years ago | (#35007338)

In the aerospace industry, even satellites are referred to as a spacecraft.

Re:Spaceship? (1)

sznupi (719324) | more than 3 years ago | (#35007892)

Would an automated container ship no longer be a ship? (there's hardly any crew on them as it now...)

Fr1st Prost ! (-1)

Anonymous Coward | more than 3 years ago | (#35007056)

It is teh prost and it Fr1st!

Re:Fr1st Prost ! (-1, Offtopic)

VincenzoRomano (881055) | more than 3 years ago | (#35007102)

Nt0 r3llay!

It's an issue of economics (0)

Anonymous Coward | more than 3 years ago | (#35007062)

We require more vespene gas.

Re:It's an issue of economics (1)

ThePromenader (878501) | more than 3 years ago | (#35008548)

Here's another plate of beans.

From the article: A major drawback (3, Insightful)

Suki I (1546431) | more than 3 years ago | (#35007084)

Or maybe not so major of a drawback.

Says it would zoom past Barnard's Star in 50 years at 12.5% the speed of light because it is not designed to go into orbit. So, it is just getting a quick look there and everyplace else it travels. By the time this thing could be built, sensor technology might be up to the task.

Re:From the article: A major drawback (3, Funny)

Onuma (947856) | more than 3 years ago | (#35007262)

We could just harpoon & tow-cable the leg of Barnard's Star as we swoop by...

Re:From the article: A major drawback (2)

macson_g (1551397) | more than 3 years ago | (#35007520)

And by the time it gets there the sensor technology could be so beefed up that we will get better data w/o leaving our cosy solar system.

Re:From the article: A major drawback (1)

sznupi (719324) | more than 3 years ago | (#35008620)

Or, in the time and budget much smaller than this thing would swallow, we might be able to build thousands solar or "artificial" [wikipedia.org] (even if not to such extremes) sails. That could give semi-continuous observation even with just flybys ... plus some might be able to slow down.

How many people? (0)

VincenzoRomano (881055) | more than 3 years ago | (#35007112)

It looks like 99% of the room is used for tanks and engines.

Re:How many people? (1)

Phoshi (1857806) | more than 3 years ago | (#35007258)

If you RTFA, it says it's an unmanned probe - so zero people. No offworld colonies for us :(

RTFA: none (1)

fantomas (94850) | more than 3 years ago | (#35007294)

RTFA:none. Unmanned probe.

Re:How many people? (1)

JasterBobaMereel (1102861) | more than 3 years ago | (#35007506)

...the failure in this is taking fuel with you

A Solar sail works with no fuel ... and with some clever steering could tour many stars (although not visit very near any of them?)

A Buzzard Ramjet (if they can build it) does not need any fuel, it gathers it as it goes...and could accelerate forever ?

Re:How many people? (1)

ultrasound (472511) | more than 3 years ago | (#35007954)

It may be able to accelerate forever, however the rate of acceleration will tend to zero as your velocity tends to c.

Re:How many people? (1)

sznupi (719324) | more than 3 years ago | (#35008046)

A Buzzard Ramjet (if they can build it)

(...and if it can create more thrust than drag, which might very well be not the case)

Re:How many people? (1)

Dragonslicer (991472) | more than 3 years ago | (#35008060)

A Buzzard Ramjet (if they can build it) does not need any fuel, it gathers it as it goes...

I don't think you'll find many dead animals on the side of the road going through space.

Re:How many people? (1)

mauriceh (3721) | more than 3 years ago | (#35008298)

That is "Bussard" , after Prof. Robert W. Bussard, who postulated it first:

http://en.wikipedia.org/wiki/Robert_W._Bussard [wikipedia.org]

Problem is that it does not gather enough fuel at lower velocities, so is not much good "in system".
Collecting dust also has a price in terms of drag.

Re:How many people? (1)

Restil (31903) | more than 3 years ago | (#35008378)

Well, in all fairness, this IS a Sci-FI article (at least according to Slashdot), so your points have merit in that respect.

However, being realistic, solar sails would only work until you reach the heliopause, after which the solar wind would have less force on the sails than whatever floating around out there would. There's no way you could accelerate to any useful speed that way.

As for Ramjets, the theory is sound, assuming there is actually enough fuel to utilize. However, space is VERY empty. My (probably slightly inaccurate) calculations figure that moving at 10% of the speed of light through interstellar space, it would take almost 10 minutes to accumulate 1 gram of matter, assuming a gathering area of one cubic kilometer. That means.. in 50 years, you will have gathered the combined weight of 26 humans (while travelling at 10% of the speed of light). That doesn't even figure how you got it to go that fast in the first place. Considering how massive such a craft would need to be, an extra 2000 pounds of weight isn't going to make the slightest bit of difference if you just included it when you left home, and not bother with the ramjets at all.

-Restil

Re:How many people? (2)

sznupi (719324) | more than 3 years ago | (#35007940)

It looks like 99% of the room is used for tanks and engines.

Rocket equation and physics in general is a bitch, isn't it? (that 99% is not much worse than with all our current launch vehicles)

Think Positron Engine Drive (3, Informative)

tyrione (134248) | more than 3 years ago | (#35007178)

WSU Positron lab: http://www.cmr.wsu.edu/facilities/webster_547 [wsu.edu]

W.M. Keck Lab [wsu.edu]

This article and video explains their research: http://wsutoday.wsu.edu/pages/publications.asp?Action=Detail&PublicationID=14531&TypeID=1 [wsu.edu]

Re:Think Positron Engine Drive (4, Insightful)

wagnerrp (1305589) | more than 3 years ago | (#35007754)

Antimatter reactions are ridiculously energetic, with an energy density of some 90PJ/kg. The problem is that there is no known naturally occurring source of antimatter, we have to produce all that we want to use. That makes it nothing more than a battery technology. Add in the inefficiencies of antimatter production, and you're talking about energy requirements equivalent to centuries at our current global consumption rate just to get into orbit. Finding a way to densely store the stuff is just one of many very difficult problems that need to be solved.

Re:Think Positron Engine Drive (1)

lollacopter (1758854) | more than 3 years ago | (#35007920)

Not to detract from your post, as I suspect it changes little, but there is a naturally occurring source of anti matter.

http://www.nasa.gov/mission_pages/GLAST/news/fermi-thunderstorms.html [nasa.gov]

Re:Think Positron Engine Drive (1)

OolimPhon (1120895) | more than 3 years ago | (#35009104)

Problem solved... just take a thunderstorm with you!

Re:Think Positron Engine Drive (1)

ultrasound (472511) | more than 3 years ago | (#35007980)

The problem is that there is no known naturally occurring source of antimatter

Apart from thunderstorms [space.com] of course.

Re:Think Positron Engine Drive (1)

sznupi (719324) | more than 3 years ago | (#35008876)

At least millennia, and probably millions of years - not centuries. One of CERN pages describes how our total production of antimatter up to this point could power a light bulb for a few minutes (and how an amount for a bomb of fairly normal yield, in the range of typical small thermonuclear one, would take billions of years to produce - since the energy involved would be not too far from the amounts in large orbital launch, I might leave more than enough space for improvement when saying "millennia, and probably millions of years")

Re:Think Positron Engine Drive (1)

Kell Bengal (711123) | more than 3 years ago | (#35009470)

Mind you, we aren't really going out of our way to produce large quantities of antimatter at the moment. One wonders how the technology to do so would scale if we mass produced the equipment necessary to synthesize it. Ultimately, producing any product in volume is simply a matter of scaling up the fabrication process. Sure, it would be extremely expensive at the start, but so were computers once upon a time.

Re:Think Positron Engine Drive (1)

sznupi (719324) | more than 3 years ago | (#35009632)

We aren't going out of our way to try doing very many things. That's not merely a matter of choice... (however amusing mass production of particle accelerators would be)

Re:Think Positron Engine Drive (2)

kiwix (1810960) | more than 3 years ago | (#35009146)

That makes it nothing more than a battery technology.

Given that the huge majority of the weight of any spacecraft is taken up by the fuel, an efficient "battery technology" would be a major breakthrough. If your fuel has a high energy density, it means your spacecraft will be lighter, and therefore require less energy.

Re:Think Positron Engine Drive (0)

Anonymous Coward | more than 3 years ago | (#35007782)

Now how does this [http] fit into all that?

Absurd (2)

burisch_research (1095299) | more than 3 years ago | (#35007214)

Oddly enough, I was reading up on possible interstellar probes just a few days ago.

Anyway, getting to another star system is just simply such a huge task. Take for example Daedalus' design -- the economics of building such a vehicle today are such that even if we had the political willpower to do so, it would just cost so much that it would soak up our global economic output for a very long time, possibly centuries.

If we were to just wait 100 years or so, I'd put money on new physics being discovered which would allow an interstellar mission to be constructed for a tiny fraction of the cost of Daedalus (or Icarus), be completed in a fraction of the time, and have enormously increased capabilities (e.g. stopping at the target star, making a return journey, or even carrying Astronauts).

It's an interesting study, but totally impractical today. We need a better understanding of the universe before we should even give serious thought to attempting this -- it doesn't pass the back-of-the-envelope test.

I strongly disagree (4, Insightful)

captainpanic (1173915) | more than 3 years ago | (#35008116)

Oddly enough, I was reading up on possible interstellar probes just a few days ago.

Anyway, getting to another star system is just simply such a huge task. Take for example Daedalus' design -- the economics of building such a vehicle today are such that even if we had the political willpower to do so, it would just cost so much that it would soak up our global economic output for a very long time, possibly centuries.

If we were to just wait 100 years or so, I'd put money on new physics being discovered which would allow an interstellar mission to be constructed for a tiny fraction of the cost of Daedalus (or Icarus), be completed in a fraction of the time, and have enormously increased capabilities (e.g. stopping at the target star, making a return journey, or even carrying Astronauts).

It's an interesting study, but totally impractical today. We need a better understanding of the universe before we should even give serious thought to attempting this -- it doesn't pass the back-of-the-envelope test.

It's not completely absurd. The projects that mankind undertakes today are enormous (in fact, there are multiple things that are way more expensive or complicated than this Daedalus spaceship). Take for example the entire road system of the world, including all rural roads, cities, traffic lights, cars, trucks, and whatnot. It's been an enormous undertaking - yet we don't mind rebuilding it entirely every decade because we don't like bumpy old asphalt or old cars.

The ISS, with a weight of nearly 400 tons, and measuring 50x100 meters shows how much is possible for a relatively small-scale human project. All our civil achievements show how much is possible for the large-scale human projects. We don't mind changing the entire surface of our planet.

We humans look at cost/benefit estimates. If the costs are high, we don't mind, as long as the benefits are there.

The problem therefore with the Daedalus is not that it's not possible. It is that it just does not have enough benefits for mankind to invest the time, effort and resources in it.

Re:I strongly disagree (1)

Kell Bengal (711123) | more than 3 years ago | (#35009520)

Interestingly, the 'small scale' project that is the ISS happens to be the single most expensive object [wikipedia.org] . That's a hopelessly small craft compared to an interstellar vehicle.

Re:Absurd (1)

sznupi (719324) | more than 3 years ago | (#35008198)

http://chem.tufts.edu/AnswersInScience/RelativityofWrong.htm [tufts.edu]

Don't bet on new physics; there's really nothing particularly suggestive of the practical limits we stumbled upon not being there. Of our physics being very wrong (it would pretty much have to be, if you wish for practical FTL / time travel), vs. just incomplete.

(that said, yeah, there are almost certainly more practical approaches than Daedalus or Icarus)

Re:Absurd (1)

onepoint (301486) | more than 3 years ago | (#35008400)

You are thinking like most people, but not like futurist. let's use 1 examples, the guy that keeps on designing those flying cars. Everything I have read about him has come at a cost of spending money to design a specific part, each step has produced an advantage to the general population ( I am also willing to bet that certain parts of the 'segway transport' gyroscope system is in the Wii or an evolution leading to the Wii ). Also we can look at the Dyson vacuum cleaners, expensive tools to get a decent job done. But again very expensive.

then let's look at the Manhattan project, lots of money spent, with a dramatic result, and over time, the research that came from it also lead to better things ( I think HEPA filters were first thought of and designed for the project )

so with that said, let's spend money on some wild goals, most wont work, but some might.

Re:Absurd, let's wait (1)

NEDHead (1651195) | more than 3 years ago | (#35008474)

This line of thinking would have killed the PC market on Day 1.

Re:Absurd (1)

kiwix (1810960) | more than 3 years ago | (#35009238)

I think the whole point of the study is to see exactly how absurd and/or impossible that task would be. In the end, I am really impressed that current technology could realistically allow us to reach a relativistic speed. I would have assumed that to be impossible and it turns out to be just absurdly expensive. I think that's a very important result.

Followup (1)

Anonymous Coward | more than 3 years ago | (#35007324)

If you want a look at what's happening in interstellar travel today, check this out:

http://www.icarusinterstellar.org/

It's basically this Daedalus project updated for the 21st century :-)

Renoir

You Can Take It With You (0)

Anonymous Coward | more than 3 years ago | (#35007340)

Why bother with the ship? Why not just take our whole solar system with us?

http://www.sfwa.org/2009/12/you-can-take-it-with-you/

Nuclear fission propulsion (2)

AC-x (735297) | more than 3 years ago | (#35007408)

What about using nuclear fission propulsion like Project Orion [wikipedia.org] ? We already have the material and technology to make one if a way to launch without causing fallout and EMP disruption could be found.

Re:Nuclear fission propulsion (1, Informative)

CrimsonAvenger (580665) | more than 3 years ago | (#35007710)

nuclear fission propulsion, like Project Orion, is incapable of the deltaV required for anything like a quick interstellar trip.

Orion, as originally conceived, produced an Isp of less than 2000. Which implies that a 10000T spacecraft would have to carry an additional 5.4E785 tons of fuel/reaction mass.

Note that 5E785 tons is rather more than the mass of the observable universe....

Re:Nuclear fission propulsion (2)

stjobe (78285) | more than 3 years ago | (#35007912)

I don't know where you get your figures from, but according to the Wikipedia page for Specific Impulse [wikipedia.org] , the ISP for an Orion-style drive is 10.000 to 100.000.

Re:Nuclear fission propulsion (2)

stjobe (78285) | more than 3 years ago | (#35007928)

Bah, preview fail. The ISP for an Orion-style drive is 10.000 to 1.000.000.

Simple... (0)

Anonymous Coward | more than 3 years ago | (#35009374)

All we need to do is build bigger telescopes to increase the mass of the observable universe !

Re:Nuclear fission propulsion (1)

drinkypoo (153816) | more than 3 years ago | (#35007808)

Orion can't carry enough fuel for interstellar travel. Orion can probably never be launched cleanly from planetside, either. It has to be built in orbit or not at all.

Re:Nuclear fission propulsion (3, Interesting)

stjobe (78285) | more than 3 years ago | (#35008038)

Freeman Dyson published a paper called "Interstellar Transport" (Physics Today, October 1968, p. 41–45) on how to build an Orion spaceship to get to Alpha Centauri [wikipedia.org] , so yes, it could carry enough fuel for interstellar travel. Your other two points are correct though.

Re:Nuclear fission propulsion (1)

LWATCDR (28044) | more than 3 years ago | (#35009270)

Actually NASA did a study on boosting an Orion into Orbit on an uprated Saturn. It was a smallish Orion but still an Orion.

Re:Nuclear fission propulsion (1)

LWATCDR (28044) | more than 3 years ago | (#35009234)

Funny but Voyager is on an interstellar trajectory. I think your math is probably wrong on that. The Orion would have issues with a fast transit but yes it could travel interstellar distances.

Re:Nuclear fission propulsion (1)

drinkypoo (153816) | more than 3 years ago | (#35009310)

The Orion would have issues with a fast transit but yes it could travel interstellar distances.

Sorry, I meant "interstellar travel of humans who will arrive at their destination with years left on the clock". It's not big enough for a generation ship. Let's deal with practicalities here.

Re:Nuclear fission propulsion (1)

LWATCDR (28044) | more than 3 years ago | (#35009548)

Well at this point I do not consider interstellar manned missions practical at all so I would say that I was dealing practicalities. Dyson did a study of a momentum limited Orion and he got a travel time of only 44 years. Possibly in life time to see some results and well within a 20 somethings life time to get data back.
So again I would say yes it is possible and practical to use an Orion for an interstellar probe if you could get around the political and ecological issues and or get one into orbit.

Re:Nuclear fission propulsion (1)

drinkypoo (153816) | more than 3 years ago | (#35009594)

We have no experience making spacecraft which can last 44 years while supporting humans. That's a stupendously long period of time.

Buyer's remorse (2)

paiute (550198) | more than 3 years ago | (#35007526)

The problem is that if one undertakes a huge project to build a big ass ship and it launches, one hundred years later the technology will have advanced so much that we will be able to build another one which is bigger and faster. A hundred years later, the same thing. So the original ship gets to where it was going only to find that several ships are already there.

I dimly recall some science fiction works with this theme.

Re:Buyer's remorse (4, Insightful)

cowboy76Spain (815442) | more than 3 years ago | (#35007652)

Yeah... but building it will be one of the ways of improving such technology (and every other way of improving the technology costs money, too).

Re:Buyer's remorse (1)

onepoint (301486) | more than 3 years ago | (#35008600)

Yes, that's true. look at container ships, they are huge ( 10,000 TEU + ) but I can recall when 3500 TEU's were huge. TEU = http://en.wikipedia.org/wiki/Teu [wikipedia.org]

Re:Buyer's remorse (2)

Targon (17348) | more than 3 years ago | (#35007700)

The effort to construct each new ship is in itself a learning experience. As a result, even though each new ship would be that much better, it would take far longer to try to skip generations. Taken another way, if Intel waited until they could make a 16MHz chip, they would have gone bankrupt, so making the 4.77MHz 8088 was well worth the investment. While these ships may not be commercial vehicles, the technology that emerges as a function of building each ship(due to R&D) can help other projects, and will help mitigate the costs.

Now, you also have to consider that while 100 years may seem like nothing when you are looking at the complete flow of time, look at how far science and technology have come in the past 110 years, from the automobile becomming something common, to flight, to rockets and satellites, and then to landing on the moon. From that perspective, the past 100 years have been fairly eventful when it comes to science and technology. I fully expect that in the next 100 years, we WILL have bases on The Moon, and possibly Mars.

Re:Buyer's remorse (2)

captainpanic (1173915) | more than 3 years ago | (#35008196)

So, you're saying that you should never start any projects with a steep learning curve, but instead just wait (and wait, and wait) until someone else starts, and then be the 2nd to step in.

Bah. I disagree. There's always a chance that the 1st project is actually the good one... and that it's considered good enough.

Re:Buyer's remorse (1)

amorsen (7485) | more than 3 years ago | (#35008288)

The problem is that if one undertakes a huge project to build a big ass ship and it launches, one hundred years later the technology will have advanced so much that we will be able to build another one which is bigger and faster.

Yet here we are, 40 years after the moon landings, and repeating them seems about as expensive as the original effort. We certainly are not going to travel significantly FASTER to the moon this time. Perhaps the next 60 years will bring progress and you will be right.

Re:Buyer's remorse (1)

sznupi (719324) | more than 3 years ago | (#35008436)

Are we overtaking anytime soon our existing interstellar probes launched over 30 years ago? (mind you, NOT launched in the fastest way possible - a Saturn V with NERVA upper stage and ion engine & reactor borrowed from the Soviets would give Pioneers and Voyagers a heck of a lot more kick - it was not for strictly technical reasons why we didn't do it ... but, funnily enough, we couldn't do it the "faster way" now!) Are current planes much faster / different than those from half a century ago? Do we build ships defying Archimedes' principle? (come on, that's over 2 thousands years old! Surely it should pass by now)

You really can't assume a technological scenarios depicted in works of fiction. Look at those airplanes [goo.gl] (probably influenced by rapid advances in naval technology, plus an unhealthy doze of wishful thinking) from "our" times, as depicted over a century ago. Vs. what reality actually dictates [wikimedia.org]

Re:Buyer's remorse (1)

guruevi (827432) | more than 3 years ago | (#35008968)

You could just send them different ways much like the Pioneers and Voyagers.

Re:Buyer's remorse (0)

Anonymous Coward | more than 3 years ago | (#35009048)

Brilliant, so you can 'bravely' volunteer to be the first to reach a new world, to do all the work, to build a society, etc. Of course, you'll know that by the time you get there, there will be McDonalds and Starbucks, and you'll be received as heroes - possibly near-mythical heroes - eventually turning up after thousands of years.

Automation has a long long way to go (1)

tm2b (42473) | more than 3 years ago | (#35007560)

I have to say, it's depressing that at this point we can't even get a solar sail to come out of a can in orbit reliably. [wired.com]

I have to think that our ability to engineer unmanned system has to grow by many orders of magnitude more than our propulsions technology has to, for us to really think about this kind of project.

Re:Automation has a long long way to go (3, Interesting)

Sockatume (732728) | more than 3 years ago | (#35007708)

I think you'll find that we can do that [wikipedia.org] , if by "we" you mean the human race. IKAROS has passed Venus, and is still going strong.

We should build an interstellar probe (1)

Baron_Yam (643147) | more than 3 years ago | (#35007874)

I'd love to see an interstellar probe, the best humanity can build with today's technology, sent to round the nearest star and return.

The goal should be to have to make it back to earth within a human lifetime, which should be either just barely possible (~80yrs) or easily possible (~40yrs) depending on the current state of a few of the more advanced propulsion technologies that have actually had some practical testing done in the lab.

Re:We should build an interstellar probe (0)

Anonymous Coward | more than 3 years ago | (#35008442)

We're nowhere near this capability. Sorry, but Space Nuttery is going to have to wait for life extension to work first.

Intergalactic Behemoth (0)

Anonymous Coward | more than 3 years ago | (#35007902)

SUCH a poor understanding of the subject...

And a flash viewer, WHY? What have they gained from using flash for this? Un-scrollable text, that's what!

Re:Intergalactic Behemoth (1)

Java Pimp (98454) | more than 3 years ago | (#35008670)

Nah, the text is scrollable. You just have to go back to 1995 and actually use the scroll bar...

Daedalus class (5, Funny)

rossdee (243626) | more than 3 years ago | (#35007918)

I thought the Daedalus incorporated a lot of Asgard technology, including Hyperdrive and site to site beaming ability. It would be very useful to have since it can go to other nearby galaxies (Like Pegasus)
Heres some info: http://stargate.wikia.com/wiki/Daedalus

Miniaturization (1)

captainpanic (1173915) | more than 3 years ago | (#35008336)

I would recommend to see how all components scale down. If you make everything smaller by the same factor, does performance suffer?

Or, in other words, for which components is a certain size essential? And how big is that?

Reduce the mass by half, reduce the fuel by half... and find which components cannot be made any smaller, or which do not scale linearly with the fuel needs or performance... Push the limits of some components to make them smaller (and invest heavily in those miniturization bottlenecks, because they might pay themselves back easily if the whole project becomes smaller).

Pointing a sign (1)

mattr (78516) | more than 3 years ago | (#35008808)

Great! It will be a big sun-hot arrow pointing right back at us saying, "Here are some young pushovers!"

It's very cool but I'd like to see the engineering plan.. can we currently afford to build it nor fix it unless we have industrial nanotech that can eat up huge mountains and turn it into high tensile steel..?

Meanwhile that tiny joint above the engine looks like the weak point. Aside from all the other parts that get hit by pebbles in orbit around Barnard's Star at 12% of c..

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