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Star Trekkin' to Alpha Centauri

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posted on Apr, 1 2015 @ 06:40 PM
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originally posted by: VoidHawk

originally posted by: ObsidianEclipse

originally posted by: VoidHawk
What about a giant accelerater? Something like Cern but on a bigger scale and built in space. Theoretically it ought to be able to launch something at near light speed?

Dont know how they'd get back though


The problem is even at a constant rate of rotation the object is subject to a change in velocity which would great unbelievable g-force affects (think about the g-force simulators they put pilots in). The accelerator would have to be huge, on the scale of the earths orbit around the sun so that probe wasn't ripped apart by a hundred g's, if you wanted to get the probe up to a decent velocity. There would unlikely be the mass of materials in the entire earth to construct it.


When I had that thought I was thinking of an accelerater like cern, but linear, rather like a giant electronic rifle. Hadn't really given it that much thought when I wrote that, and your comments about g-forces are still valid in my linear version.

Assuming a person were accelerating at the maximum g-force that a human can withstand, I wonder how long it would take to reach half light speed, anyone know?


Using the math above, 88 days at 1g acceleration would require a linear accelerator roughly 280000000000km long (or 1871 astronomical units). I can't knock the idea though.




posted on Apr, 1 2015 @ 10:12 PM
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originally posted by: Aazadan

originally posted by: stormbringer1701
the vast majority of potential impactors are 10 microns or less in size. at that size at 92 percent c (a tad above the ten percent C ships we are discussing) you would statistically run into one of those per square meter on the front cross section of the ship per day of travel. these produce a kinetic energy similar to a high powered rifle bullet. sand grain sized impactors are very much rarer. and those bigger than that are even rarer the bigger they get. in other words you could get to alpha centauri without hitting on good throwing sized rock. but if you did hit one it would be like an atomic bomb. but that presumes you cannot do anything about running into such rocks. there is no reason to presume that. stop it.



They get rarer, but how much rarer? The longer the mission goes the greater the chance of an impact and the more wear you get on the probe due to accumulated smaller impacts. Using your example, at 92% c you would get 1 per square meter per day, so 10% c would roughly be 1 per square meter per 9 days. A 60 year mission would be nearly 22,000 days so that's 2400 impacts. How much rarer are sand sized particles? 50x as rare? That's 48 of those impacts. What about a throwing sized rock? Would we have a 1/3 chance of impact during the mission? That's a 33% failure rate. Better send more probes in that case for redundancy. Two probes gets us to a 10% failure rate, three probes to 3%, four probes to 1%. How many would we need to build and send?

I'm not saying that we shouldn't do it but you have to look at cost effectiveness at some point as long as NASA is being as constrained in their budget as they are. For the price of a mission to Alpha Centauri maybe we could get a mission to every planet in the solar system or one of those big budget items NASA wants to put up in space, or some good work done on a space elevator.
I get the impression that they are nearly exponentially rarer as you go up in size.

However; remember a simple coffee can sized plasma generator can handle anything up to around pea sized. and...

I think... at least, as these critters come towards you because of relativistic effects they emit blue shifted light. if you are going really really fast they emit RF then X rays and finally gamma rays. it's not as if an appropriate sensor can't see some thing like that. "Hey look! there is a lethal gamma ray source, non intermitant, gravel sized, not a pulsar, quasar, blackhole or star!"

"Lock fruiton torpeders on target....Fire!!!" (actually this would most likely be an automated response handled by computer and done in nanoseconds.)

A weapons grade Laser could easily vaporize up to a basketball sized target at nearly arbitrary distances at which point the plasma shield could clearly deflect the plasma or sand grain sized remnants. additionally just pitting a target turns it into a maneuver thruster as the plasmafied expanding material jets out of the laser pit hole. The energy from all that imparts a reaction in the rock as if it were a rocket made by NASA.



posted on Apr, 2 2015 @ 03:47 AM
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Some day someone is going to say "Ahead Full Impulse speed!" and a ship will actually proceed at 25 percent C:

www.technologyreview.com...

its not superluminal warp but is subluminal warp.



posted on Apr, 2 2015 @ 12:37 PM
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just wait 50/100 years or more.
and do it in 10/2 years.
in 100 year we can not even conceive
of what will be built then!



posted on Apr, 2 2015 @ 01:34 PM
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originally posted by: buddha
just wait 50/100 years or more.
and do it in 10/2 years.
in 100 year we can not even conceive
of what will be built then!


We don't typically wait though do we?

Did we wait for steam power, gas turbine or nuclear power before sailing the seas?

Nope, so why should space be any different?

Who knows, if we all waited for nuclear power before ships set sail on Earth a lot of the Earth itself today might still remain a mystery.
edit on 2-4-2015 by JadeStar because: (no reason given)



posted on Apr, 2 2015 @ 01:49 PM
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originally posted by: stormbringer1701
A weapons grade Laser could easily vaporize up to a basketball sized target at nearly arbitrary distances at which point the plasma shield could clearly deflect the plasma or sand grain sized remnants. additionally just pitting a target turns it into a maneuver thruster as the plasmafied expanding material jets out of the laser pit hole. The energy from all that imparts a reaction in the rock as if it were a rocket made by NASA.


This is an interesting idea but I suspect the force of the part of the object that shoots off after the laser hits wouldn't deflect it from the path of the probe. Instead you would probably look to break the object up and spread the force of impact over a larger area.

I hadn't thought about lasers being used in this way, but I bet it would work. What do you do for the energy requirements though? I was under the impression that our current lasers are relatively short distances (atleast in our atmosphere, no idea about space) and that the power plants for them take up a lot of space. And the current anti missile tech still has trouble, with missiles being larger and slower targets than these rocks. Is this really something we have the technology to put on a probe right now? Or is it something that we can't realistically do for another 20 years?
edit on 2-4-2015 by Aazadan because: (no reason given)



posted on Apr, 2 2015 @ 02:26 PM
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originally posted by: Aazadan

originally posted by: stormbringer1701
A weapons grade Laser could easily vaporize up to a basketball sized target at nearly arbitrary distances at which point the plasma shield could clearly deflect the plasma or sand grain sized remnants. additionally just pitting a target turns it into a maneuver thruster as the plasmafied expanding material jets out of the laser pit hole. The energy from all that imparts a reaction in the rock as if it were a rocket made by NASA.


This is an interesting idea but I suspect the force the laser hits the object with wouldn't deflect it from the path of the probe. Instead you would probably look to break the object up and spread the force of impact over a larger area.

I hadn't thought about lasers being used in this way, but I bet it would work. What do you do for the energy requirements though? I was under the impression that our current lasers are relatively short distances (atleast in our atmosphere, no idea about space) and that the power plants for them take up a lot of space. And the current anti missile tech still has trouble, with missiles being larger and slower targets than these rocks. Is this really something we have the technology to put on a probe right now? Or is it something that we can't realistically do for another 20 years?


the footprint of weapons grade laser went from something you needed a jet liner for to something about ready to go into a fighter. this is because several technologies made leaps in sophistication and power and with optically steered beams which are nearing tech readiness level warranting fielding, there is no time lost to slewing in azimuth and elevation via mechanical motors gears or hydraulics. further sensor and shooter channels can be in the same array. and the array can cover about 120 degrees sort of like a flat screen TV viewing angle has improved.



posted on Apr, 3 2015 @ 09:46 AM
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a reply to: JadeStar

I've read that VASIMR has received a much needed shot in the arm (you are probably already aware of this.)



Nasa has selected a variety of companies to work on projects to create advanced space technologies, including faster methods of propulsion.

And one of the companies in the 12 Next Space Technologies for Exploration Partnerships (NextStep) says they have an engine that could get humans to Mars in just 39 days.

Over three years, Nasa will give the company about £6.8 million ($10 million) to get the engine almost ready to fly in space.

‘We are thrilled by this announcement and proud to be joining forces with Nasa in the final steps of the technology maturation,’ said Dr Franklin Chang Diaz, Ad Astra’s Chairman and CEO, in a statement.


Daily mail

Some of these proposed propulsion systems were exciting but at the end of the day it was politics or funding that eventually halted projects like NERVA. However NERVA was devised decades ago and propulsion has advanced a lot since then.

I'm starting to think it's only a matter of time before we see the first Von Neumann probe, as long as politics and funding doesn't hamper the development of future spaceflight again.



posted on Apr, 3 2015 @ 12:45 PM
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originally posted by: Aazadan

originally posted by: stormbringer1701
the vast majority of potential impactors are 10 microns or less in size. at that size at 92 percent c (a tad above the ten percent C ships we are discussing) you would statistically run into one of those per square meter on the front cross section of the ship per day of travel. these produce a kinetic energy similar to a high powered rifle bullet. sand grain sized impactors are very much rarer. and those bigger than that are even rarer the bigger they get. in other words you could get to alpha centauri without hitting on good throwing sized rock. but if you did hit one it would be like an atomic bomb. but that presumes you cannot do anything about running into such rocks. there is no reason to presume that. stop it.



They get rarer, but how much rarer? The longer the mission goes the greater the chance of an impact and the more wear you get on the probe due to accumulated smaller impacts. Using your example, at 92% c you would get 1 per square meter per day, so 10% c would roughly be 1 per square meter per 9 days. A 60 year mission would be nearly 22,000 days so that's 2400 impacts. How much rarer are sand sized particles? 50x as rare? That's 48 of those impacts. What about a throwing sized rock? Would we have a 1/3 chance of impact during the mission? That's a 33% failure rate. Better send more probes in that case for redundancy. Two probes gets us to a 10% failure rate, three probes to 3%, four probes to 1%. How many would we need to build and send?

I'm not saying that we shouldn't do it but you have to look at cost effectiveness at some point as long as NASA is being as constrained in their budget as they are. For the price of a mission to Alpha Centauri maybe we could get a mission to every planet in the solar system or one of those big budget items NASA wants to put up in space, or some good work done on a space elevator.
I'll go looking for that material . it's probably at centauri dreams or project rho or at one of the sites like that. so just for now (i'm using the force and my vague traces of memory here) i'd say the sand grains were on the order of thousands of times rarer. but like i said i will try to find the proper cites.



posted on Apr, 3 2015 @ 01:10 PM
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as i suspected here is daedalus studies projected impact figures:

www.centauri-dreams.org...

www.centauri-dreams.org...

and so on.

project rho's figures on this subject were preposterous. at least the one i found right away. Rho does generally do a great job though.



posted on Apr, 4 2015 @ 04:13 AM
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a reply to: JadeStar

Traveling through Star gate or wormhole should be faster.



posted on Apr, 4 2015 @ 07:53 AM
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someone is working on that. PHD James Woodward: (Please hang in there old timer; don't give up on your fights)

physics.fullerton.edu...

lots of links there and here:

ssi.org...


edit on 4-4-2015 by stormbringer1701 because: (no reason given)



posted on Apr, 4 2015 @ 12:30 PM
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originally posted by: Normallysane
a reply to: JadeStar

Traveling through Star gate or wormhole should be faster.


That's true. Unfortunately for us star gates are the stuff of sci-fi and the nearest wormhole, if they exist at all is probably not nearby.



posted on Apr, 4 2015 @ 08:26 PM
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While we are bumbling around with ideas. How about a few alternate methods of propulsion. Coming from a very amateur observer feel free to shoot the ideas down. Just don't shoot the messenger.
1) We now have the ability to use a railgun to propel an object. Could we use the pusher idea and slam projectiles into it from an orbiting rail gun? The more impacts the greater the acceleration. Until it gets out of range then you need to switch to a more long lasting method.
2) The talk about using a very large rail gun like system that would have to be too large could it be done in segments? Spaced out at regular intervals to give added speed to a probe. Less need for a large probe. Hitting the target at that velocity sounds like areal tricky thing though. One mistake and you wipe out the system and the probe... Nah that one is too far out.
3) Why send a single probe out? Send out a swarm that puts it self together at the destination. If any thing gets damaged in route the others can make up for it. Like a Von Neumon type probe but a bit more primitive.
4) We use booster rockets for a one shot acceleration. Could we set up a planetary escape system / interstellar launch booster that would allow us to boost the probe on its way and then return for multiple usages? That not touch on the how of the propulsion. Fell free to point that out. Would that reduce cost or just make things more complex than they need to be?



posted on Apr, 5 2015 @ 05:23 AM
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That's true. Unfortunately for us star gates are the stuff of sci-fi and the nearest wormhole, if they exist at all is probably not nearby.


Sci-fi really? do a Google Search "NASA opens star gate portal ", "NASA Discovers Hidden Portals In Earth’s Magnetic Field".

edit on 5-4-2015 by Normallysane because: (no reason given)



posted on Apr, 5 2015 @ 05:35 AM
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originally posted by: datasdream
While we are bumbling around with ideas. How about a few alternate methods of propulsion. Coming from a very amateur observer feel free to shoot the ideas down. Just don't shoot the messenger.
1) We now have the ability to use a railgun to propel an object. Could we use the pusher idea and slam projectiles into it from an orbiting rail gun? The more impacts the greater the acceleration. Until it gets out of range then you need to switch to a more long lasting method.
2) The talk about using a very large rail gun like system that would have to be too large could it be done in segments? Spaced out at regular intervals to give added speed to a probe. Less need for a large probe. Hitting the target at that velocity sounds like areal tricky thing though. One mistake and you wipe out the system and the probe... Nah that one is too far out.
3) Why send a single probe out? Send out a swarm that puts it self together at the destination. If any thing gets damaged in route the others can make up for it. Like a Von Neumon type probe but a bit more primitive.
4) We use booster rockets for a one shot acceleration. Could we set up a planetary escape system / interstellar launch booster that would allow us to boost the probe on its way and then return for multiple usages? That not touch on the how of the propulsion. Fell free to point that out. Would that reduce cost or just make things more complex than they need to be?
the rail gun idea would be extremely inefficient because of losses only "a little" (relatively speaking) of the KE from the impact would be coupled to the pusher. to get relativistic speeds you would need to accelerate the projectiles to relativistic speed as the ship accelerates (otherwise the projectiles would fall behind the ship) but there is hope. advanced versions of the old Orion idea have been proposed. the new idea means you don't have a proliferation problem with mini fusion bombs or fission bombs. instead you have tiny deuterium pellets fused by a circular firing squad of high powered lasers. you get the same bang for the buck, faster detonation cycles, thousands of times more fuel pellets than bombs in the same volume, no initial radiation, security, and other precautions required for bombs because the pellets are harmless in storage.



posted on Apr, 5 2015 @ 05:49 AM
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originally posted by: datasdream
While we are bumbling around with ideas. How about a few alternate methods of propulsion. Coming from a very amateur observer feel free to shoot the ideas down. Just don't shoot the messenger.
1) We now have the ability to use a railgun to propel an object. Could we use the pusher idea and slam projectiles into it from an orbiting rail gun? The more impacts the greater the acceleration. Until it gets out of range then you need to switch to a more long lasting method.
2) The talk about using a very large rail gun like system that would have to be too large could it be done in segments? Spaced out at regular intervals to give added speed to a probe. Less need for a large probe. Hitting the target at that velocity sounds like areal tricky thing though. One mistake and you wipe out the system and the probe... Nah that one is too far out.
3) Why send a single probe out? Send out a swarm that puts it self together at the destination. If any thing gets damaged in route the others can make up for it. Like a Von Neumon type probe but a bit more primitive.
4) We use booster rockets for a one shot acceleration. Could we set up a planetary escape system / interstellar launch booster that would allow us to boost the probe on its way and then return for multiple usages? That not touch on the how of the propulsion. Fell free to point that out. Would that reduce cost or just make things more complex than they need to be?

The issue with any gun are the forces acting during the acceleration. And for practical reasons you won't want to build really long guns.

But the general idea to avoid carrying energy and propellant is reasonable. One known idea is beam-powered propulsion using masers, lasers, light sails. Another variant would be to use a magnetic sail reflecting charged particles or objects shot at it with a particle/object accelerator (rail gun).

You'll still have to figure out a way to decelerate at your destination though.




posted on Apr, 5 2015 @ 07:33 AM
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originally posted by: moebius

originally posted by: datasdream
While we are bumbling around with ideas. How about a few alternate methods of propulsion. Coming from a very amateur observer feel free to shoot the ideas down. Just don't shoot the messenger.
1) We now have the ability to use a railgun to propel an object. Could we use the pusher idea and slam projectiles into it from an orbiting rail gun? The more impacts the greater the acceleration. Until it gets out of range then you need to switch to a more long lasting method.
2) The talk about using a very large rail gun like system that would have to be too large could it be done in segments? Spaced out at regular intervals to give added speed to a probe. Less need for a large probe. Hitting the target at that velocity sounds like areal tricky thing though. One mistake and you wipe out the system and the probe... Nah that one is too far out.
3) Why send a single probe out? Send out a swarm that puts it self together at the destination. If any thing gets damaged in route the others can make up for it. Like a Von Neumon type probe but a bit more primitive.
4) We use booster rockets for a one shot acceleration. Could we set up a planetary escape system / interstellar launch booster that would allow us to boost the probe on its way and then return for multiple usages? That not touch on the how of the propulsion. Fell free to point that out. Would that reduce cost or just make things more complex than they need to be?

The issue with any gun are the forces acting during the acceleration. And for practical reasons you won't want to build really long guns.

But the general idea to avoid carrying energy and propellant is reasonable. One known idea is beam-powered propulsion using masers, lasers, light sails. Another variant would be to use a magnetic sail reflecting charged particles or objects shot at it with a particle/object accelerator (rail gun).

You'll still have to figure out a way to decelerate at your destination though.

one way to daccelerate is to generate a magnetic field and inject plasma into it. this causes the initial field or balloon to expand radically. it's even called inflation. you can get a parachute that is over 100 kilometers across to react against the target star systems' stellar wind. even if the parachute does not slow completely on the first pass you can hook around and take as many passes as it takes to achieve stellar gravity capture and then planetary orbital capture. and that's without using rocket powered braking. if you add some of that...



posted on Apr, 7 2015 @ 04:32 PM
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space suit and space ship armor: www.technovelgy.com...

yes it is only about a garment but if you had enough of this it would stop micro-meteoroids.



posted on Apr, 8 2015 @ 05:01 PM
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a reply to: stormbringer1701

Weight is always going to be a problem for spacecraft. So unless fusion or anti-matter comes about, it's not feasible to load them up with armour & all the extra weight they carry.

In this case, that armour might stop most bullets, but imagine a pebble sized bit of rock impacting your ship while it's going 10% the SOL.

If graphene armour or the like is ever practical then that's a different story altogether as it's super tough & super light. So you could layer this stuff up on your ship & it would take the small impacts with ease.

There will most likely be a multi-stage approach taken. A lightweight armour. A plasma forcefield held in place by a magnetic field & an energy weapon to take care of any larger pieces of debris that threatens the ship.



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