# interstellar travel

Discussion in 'Astronomy, Exobiology, & Cosmology' started by Bxmkr, May 19, 1999.

1. ### jumpercable6EQUJ5 'WOW'Registered Senior Member

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There's nothin like a little 'Air Braking' to slow you down. (Remember the movie > '2010'?) Just inflat a couple of blimp-sized balloons on the side of your mile-long spaceship before you get ready to orbit Zeta2 Reticuli and then start braking. Could work. Of course it's possible you may have to make a few hundred orbits around Zeta2 Reticuli inorder to slow your mile-long spacecraft down enough to stick your head out the spaceship's window to say hello.

Last edited: Jan 26, 2007

3. ### orcotValued Senior Member

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okay I have to ask what is so special abouth Zeta2 Reticuli?

5. ### jumpercable6EQUJ5 'WOW'Registered Senior Member

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Bob Lazar seems to think that our so-called captured advanced flying saucer technology that is/or was secured in one of the hangers in Area 51 comes from the Zeta Reticuli star system.

www.boblazar.com

Last edited: Jan 26, 2007

7. ### eburacum45Valued Senior Member

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That wouldn't work very well; you would still be traveling too fast after the first attempt at air braking so you would end up in a hyperbolic orbit, which would take you out of the system altogether.
But you could try a magnetic brake; use a magnetic ramscoop, like a Bussard ramjet, to brake against the material in the target solar system. This braking system could be made arbitrarily large, so you would eventually grind to a halt.

8. ### jumpercable6EQUJ5 'WOW'Registered Senior Member

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Forget the so-called elliptical orbit stuff. You can always reverse your mile-long Daedelus spacecraft on the way there and explode a nuke infront of you to slow you down so you can do a little 'air-braking' to get you into a circular orbit.

9. ### orcotValued Senior Member

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Some sort of magnetic solar sail would proberly do the trick, the craft would be much lighter because it almost has zero fuel left. Making a nuke in front of you would proberly vaporize at least a portion of your own space ship so it proberly wouldn't work to brake like this.
I wonder if they could use a cable and use the death weight of the massive empty fuel tanks to gradually rotate the empty tanks around the leftover ship and then let the the empty tank go, the empty tank should then move even fasther then 12%c and therefore the rest of the craft would go slower. That in combination with the solar sail and perhaps and perhaps some other minor tricks could slow a portion of the ship down enough to aerobrake

10. ### eburacum45Valued Senior Member

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Oh it would work fine; all you need to do is turn the ship around so that the explosion happens in front of the engine bell.
As the ship has already accelerated by exploding numerous bomblets inside this bell it had been shown to be able to withstand this punishment.

Project Daedalus

Freeman Dyson calculated that the pusher plate of his Project Orion ships would lose no more than a 16th of an inch with each detonation (IIRC)
Nice trick; using rotation and perhaps a tether to disspate momentum. I doubt if this would work for interstellar speeds, but it is certainly worth considering for interplanetary missions.

11. ### w1z4rdCry the beloved countryValued Senior Member

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My 2 cents and imagination.

I don't think the way to move from say Point A in Galaxy A, to Point B in Galaxy B is by going really fast.

I was reading about an experiment where they took two photon/protons (cant remember exactly which) from the same atom and fired them in opposite directions. When they effected the orbit of the one particle the other particle responded by acting in an equal and opposite response.

They explained in the experiment, that the "connection" between the two particles was instantaneous and however they were connected and communicated with each did so instantaneously no matter what the distance.

I think when we find out how they are connected we will be much closer to real interstellar travel.

12. ### jumpercable6EQUJ5 'WOW'Registered Senior Member

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If you use the Daedelus spacecraft cocept, next question is; How big should the nukes be inorder to get it to 12% the speed of light or close to it inorder to get it to the nearest star system like Alpha Centauri? I would imagine anything bigger than a small nuke blast in the single digit kiloton range should do nicely. Next big question. How many nuke blasts will be needed to get the job done? Let's not forget the return trip either. You don't want to run out of nukes on the way there.

13. ### eburacum45Valued Senior Member

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whoa!
you don't want to have to carry fuel to came back as well, do you? That will make the mass of the ship far greater.
No; just plan for a one way trip for now- when you get there you can think about refining deuterium and He3 for the return journey. You might not want to go back.

As it is, the deuterium/He3 fuel weighs 100 times the payload in a Daedalus type ship; so figure out where you are going, how many people you want to take, and how massive the accomodation would be to support that many people for that length of time. If for instance your accomodation masses 100,000 tonnes, the fuel would mass 10 million tonnes. We can tentatively design our super-Daedalus craft now.

In the original proposal each pellet weighed a tenth of a gramme; I think we would have to scale that up a bit to allow for the bigger ship. But it would still mean the detonation of tens of billions of pellets over a period of about four years...
The ship would have a dry weight of 800,000 tonnes, all other things being equal.

14. ### orcotValued Senior Member

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Disspate momentum! Certainley, but I was more thinking of a decrease in mass. A craft that is down to 40% of it's original mass minus the loss of momentum will be far easier to stop then a craft that weights a 100% of it's weight and is still traveling at 12%c.

I wonder how much of a detour it would be to make a close pass of proxima centauri and use that the decelerate a bit and travel the last 0.1LY a bit slower. If you then time your arrivel that you for example do a flyby of AC-b, for a sort of solar aerobrake (not in the atmosphere but with a solar sail and gravitational push). And then a other fly by of AC-a then perhaps the craft could slow down enough to reach orbit.
3 stellar gravitational brakes, reduced mass and loss of momentem and a solar sail, it all ads up. I doubt with todays technology we will be able to stop the craft but who know, the concept of daedalus is almost 30 years old. Perhaps they will make a new sort of spook mission in a other 20 years and I'm sure even without mayor propulsion breaktroughs daedalus 2 is going to do a lot better

15. ### jumpercable6EQUJ5 'WOW'Registered Senior Member

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It will be a long time before the human race decides to head for Alpha Centauri. Chances are in the next 200 years or so, if the human race doesn't kill itself off, just maybe we might have the technology to make such a trip. However, we still haven't made it to Mars or even back to the moon yet, let alone establishing any permenent scientific research bases on anything. I still believe the space Shuttle program has sucked up too much money and has accomplished what? It's just a high priced ferry to carry astronauts, sleeping bags and fast food into orbit. Something that could have been accomplished with just using cheapers rockets like the what soviets use. If we ever get to Alpha Centauri, it won't be with using space shuttle technology.

16. ### orcotValued Senior Member

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For some reason NASA seems unwilling to apply nuclair technology and that is rather sad, because it is part of the future of space hardware.

Sigh the problem with the space shuttle was actually that it was to big and to costly. Basicly it was a wast of money the moment someone tought hey let's make a reusable spaceship to impress the russians.

To me a permanent scientific research post on the moon looks verry uninpresive A little factory where they make their own drybrick that can be used to make underground structures, would be far more inpressive then determing the silicium isotope of that particulairy bit of dust, of that particulairy rock. And that's proberly what NASA is going for.

They should send engineers up, that had a short flight education, not testflight pilots that had a short science education.

I think the science is inferior to the costs. Science (like it is today) is never going to make a structure self sufficient it's only going to close it better of from it's enviroment. And that will give problems (meaning it will cost extras).

17. ### jumpercable6EQUJ5 'WOW'Registered Senior Member

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Yea, I agree for most part of what you say. We should have been on Mars by now and have already established a scientific base there. We had the technology to get there almost 30 years ago, but thanks to politics and a wrong direction-minded short-sighted NASA, we still are reaching for the moon. O.K. Send a robot to Alpha Centauri. It's cheaper, expendable, long lived and he can recharge it's batteries again when it's get's there.

18. ### orcotValued Senior Member

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One of the mayor problems are the launch costs (.US$40,000/kg) It most simply costs to much to launch a kg to space. However that may change when the first space elevator is being build. Plannend on october 27, 2031 and will proberly be completed before 2050. And it should reduce the costs to some$350/kg.
Therefore a 54 000 000 kg space ship like daedalus (would only costs 18 900 000 000\$

) without constructing costs

19. ### jumpercable6EQUJ5 'WOW'Registered Senior Member

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I've always thought that the space shuttle could be modified to some extent for a manned trip to Mars. It could have a martian lander attached to it and have enough room to carry a 4-man crew, enough food, fuel and scientific equipment for a 9 month journey to Mars and back. But I always hear that it is not feasable to modify the space shuttle for such as journey. So, tell me why not?

20. ### orcotValued Senior Member

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you wouldn't wreally need that much scientific payload in your orbiter only in your lander right. Besides the power systems wont proberly last for a 2 times 6 month voyage and x months on the ground (Thats a lot of adaptation).
Further there are going to be navigation problems and mass problems the shuttle weights 68 586.6 kg the service module weighted only 30 332 kg and that's a big difference

21. ### jumpercable6EQUJ5 'WOW'Registered Senior Member

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I think it's well within NASA's engineering technology to do it. In terms of navigational problems? If they can navigate the space shuttle to dock with the International Space Station, one would think that they could navigate it to an orbit around Mars too?

Last edited: Jan 28, 2007
22. ### orcotValued Senior Member

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perhaps... it can be adapted to go to mars certainley not alpha centauri, but it would involve carring a lot of death weight, wings, weels, robotic arm, sides and roof arounds the cargo bay if the lander is inside, the cargo bay altogether if it's hanging outside. Besides the engines of the space shuttle use liquid hydrogen right, I believe that there is a natural boil of so you would need to take more fuel. Also the normal exterior tank isn't big enof to send the space shuttle outside earths orbit so there has to be a second rocket. Then their is the long time exposiur of radiation aren't those heat tiles pastet on, the glue will defenitley hold for a week in space but who knows what the radiation will do afther a year of exposure.

23. ### rturnerRegistered Member

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Ross Turner;

I'm new to these threads, bt to be quite honest i would say that the most ample way of traveling to the distant stars would be through using wormholes.
Space is made of covulents of Dark Matter, i have found a way of creating Anti-Matter so in order i can control Dark Matter bending it or even moving it.
So with this new technology, i believe we should be able to bend space at our will thus creating a an empty space, which has no time, gravity Dark Matter anything. So we would pass through it instantly. Now that i belive will be the future.