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#26 2016-06-28 15:22:06

Tom Kalbfus
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Re: Earth has captured a second moon, says NASA

GW Johnson wrote:

Mass drivers are still a science lab project,  not an actual deployable technology.  Needs a lot of development work.  The closest item is the rail gun.  I notice that it is not yet deployed yet with the navies of the world,  except as an experimental item here and there.  That should tell you something.

GW

Would you like to stand in front of one as it flings its payload? Do you have that much confidence in it not working, would you stake your life on it? I notice that SSI build a few in the 1980s, did we forget how to build one since?
I think NASA is just afraid to try new technologies, they like rockets and ion drives, they don't like rock throwers, that is just too crude!

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#27 2016-06-28 15:52:33

GW Johnson
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Re: Earth has captured a second moon, says NASA

None of the world's navies is yet betting command of the seas on the mass driver technology embodied as the rail gun.  So,  would you like to bet your country's continued existence on it?  Not me.  Not yet.  It ain't ready.  Simple as that.

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#28 2016-06-28 17:13:42

Tom Kalbfus
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Re: Earth has captured a second moon, says NASA

GW Johnson wrote:

None of the world's navies is yet betting command of the seas on the mass driver technology embodied as the rail gun.  So,  would you like to bet your country's continued existence on it?  Not me.  Not yet.  It ain't ready.  Simple as that.

GW

Naval guns rely on specialized materials, mass drivers do not. I don't think it would be practical to mount a naval gun on an asteroid, and make smokeless powder and cast shells and fire them for propulsion. You see out in space, we don't have munitions factories, and we don't want to rely on chemicals to provide the energy for propulsion. Mass drivers rely on electricity to hurl rocks and dirt to push the asteroid in the opposite direction, they don't need to be good at targeting either. Everything NASA has used for propulsion has relied on specific materials as reaction mass ion drives rely on mercury or some other material to be ionized, if that asteroid isn't made up mostly of that stuff, it is useless. Chemical rockets require a plant to make the chemicals. Its possible to mount a hydrogen-Oxygen rocket on an asteroid and then mine the asteroid for water, split it into its components with electricity then burn it, but why? An Asteroid in Earth's vicinity isn't likely to contain a lot of water. Hurling rocks doesn't depend on our finding certain materials within the asteroid, we can fling any material that has mass.

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#29 2016-06-28 18:52:11

GW Johnson
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Re: Earth has captured a second moon, says NASA

Tom,  you idiot,  learn to read!  I never said one word about putting naval guns in space!  YOU DID!  NOT ME. 

Most ships today use missiles not guns anyway,  so your understanding of that technology is fatally flawed from the word "go". 

What I said was "mass drivers are not yet a deployable technology".  That is ALL I said!  Nothing more. 

GW

Last edited by GW Johnson (2016-06-28 18:54:01)


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#30 2016-06-28 20:36:20

Tom Kalbfus
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Re: Earth has captured a second moon, says NASA

GW Johnson wrote:

Tom,  you idiot,  learn to read!  I never said one word about putting naval guns in space!  YOU DID!  NOT ME. 

Most ships today use missiles not guns anyway,  so your understanding of that technology is fatally flawed from the word "go". 

What I said was "mass drivers are not yet a deployable technology".  That is ALL I said!  Nothing more. 

GW

You lack a sense of humor. Missiles by the way would work, if you could turn asteroid material into missiles. Most missiles use chemical fuel however, that would still require manufacturing fuel for those missiles, there is some intermediate step before you could use the chemical fuel of those missiles, that would be manufacturing the fuel, you would need to expend energy to create the fuel for those chemical rockets out of asteroid material, it would be much simpler just to use the energy to accelerate the material in one direction to push the asteroid in the opposite direction.

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#31 2016-06-29 09:23:02

GW Johnson
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Re: Earth has captured a second moon, says NASA

Sorry I didn't spot the joke.  I'm actually with you on this topic.

My point stands:  no one yet knows how to create useful materials out of the rocky minerals.  We won't know until we go out there and attempt these things.  The semi-orbiting asteroid offers a really convenient target for this.  Like you,  I think we ought to quit screwing around,  and just go out there and do it. 

Perhaps the first mission is unmanned,  just to get a set of real samples and bring them home.  Then we experiment with processes to create useful materials in the lab.  That second step must be tempered with the knowledge that the processes we eventually use,  must work in situ out there:  weightless and in vacuum. 

Then we go out there and try it out.  This is probably quite iterative,  until we get it right.  I think probability of success is higher if this step is manned:  humans can adapt to the unexpected.  Machines cannot,  unless reprogrammed by humans.  Hard to do from far away. 

Once we have an extraction and refining process worked out,  that can be automated.  Materials production in mass quantities by automated machines outside Earth's gravity well would be a big step forward toward space settlements and structures of all kinds. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#32 2016-06-30 21:44:57

SpaceNut
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Re: Earth has captured a second moon, says NASA

I agree that the methods here on earth will not totally work as the lack of gravity would allow for many pieces of the crushing and breaking processes used here on earth would create. Thats just one side of the issue as for where will we power the machines from if we do not use nuclear for this.

Commercial Space Exploration—A Next Frontier for Manufacturers?

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#33 2017-03-15 17:51:46

SpaceNut
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Re: Earth has captured a second moon, says NASA

Here is a way to try out duration flight using what we have.

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