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Anti-gravity Out of Magnetics?


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In reply to an earlier post on Oct 10, 2009 7:33:45 AM PDT
Ronald Craig says:
Nice flog of your own book there, John, but supposedly this is a thread about real scientific studies on magnetic levitation and antigravity (although the wingnut who started it STILL doesn't understand the difference).

(Your book sounds like poor science fantasy at best. This is the science fiction forum.)

Posted on Oct 12, 2009 12:45:22 PM PDT
M. Helsdon says:
"the new SF Hard Jack by Hanna uses an antigravity booster to boost the hero into space. The technique, available now, is discussed in detail."

Mr. Wells was there first with "The First Men in the Moon" in 1901.

In reply to an earlier post on Oct 12, 2009 7:47:58 PM PDT
B. A. Dilger says:
In the Wells-influenced "Things To Come" (1936), the first astronauts
were fired from a giant cannon. The G's would make this impractical
for humans.

In reply to an earlier post on Oct 12, 2009 11:07:51 PM PDT
Last edited by the author on Oct 15, 2009 3:20:04 AM PDT
M. Helsdon says:
B.A Dilger,

"In the Wells-influenced "Things To Come" (1936), the first astronauts
were fired from a giant cannon. The G's would make this impractical
for humans."

Wells wrote the book "The Shape of Things to Come" and was involved in the making of the movie.

The same problem arises with the more recent 'gas gun' reported as a viable and cheaper means to orbit: the g-force is far too high for manned capsules, plus there's also an issue with drag.

Posted on Oct 13, 2009 3:01:23 AM PDT
Last edited by the author on Oct 13, 2009 3:19:37 AM PDT
D. Kneeland says:
The maglov rail seems to be one of the more practical methods I've seen for launching vehicles into orbit. I wonder what the cost difference would be compared to the currently used escape vehicles?

I remember reading something about magnetic levitation being used to counter the health effects of space travel, though it was also mentioned that to be effective it would require (if memory serves me correct) 20 tons of additional mass and the ability to generate 2 MW to power it. Thous making it impractical as of yet and potentially dangerous. It looks like the use of inertia for artificial gravity is still the most practical method. Actually wasn't that one of the goals of the planned moon landing? To find out if the 0.165g on the moon would cause the same issues of calcium loss as in microgravity or at what rate and extent this occurs at differing levels of less than 1g.

In reply to an earlier post on Oct 13, 2009 4:44:16 AM PDT
M. Helsdon says:
D. Kneeland,

"The maglov rail seems to be one of the more practical methods I've seen for launching vehicles into orbit. I wonder what the cost difference would be compared to the currently used escape vehicles?"

It depends on whether the payload is manned or not: an unmanned vehicle can be accelerated over a shorter distance to a high velocity, but one carrying humans is subject to a maximum g, meaning that the track has to be longer and thus more expensive. Both payloads will suffer from drag and potentially aerodynamic heating. A maglev track looks to save a reasonable percentage, which over time would pay back the initial investment.

Posted on Oct 13, 2009 6:25:48 AM PDT
D. Kneeland says:
Yes. It kinda reminds me of the old idea to use a rail gun, and likely has similar issues, though possibly more manageable.

I was thinking. Maybe you could have something along the lines of a maglov rail for unmanned vehicles or equipment and use a scramjet with booster rockets for the astronauts. The idea being that in a mission to the moon or mars, the assembly of the primary mission vehicle, equipment and supplies could be conducted at the ISS and the crew could then be sent up when things are finished and off they role. Granted there's some logistical issues, but it would help solve the issues of getting larger extra orbital vehicles off the planet more efficiently. Maybe.

Posted on Oct 13, 2009 11:56:35 AM PDT
M. Helsdon says:
D. Kneeland,

"Maybe you could have something along the lines of a maglov rail for unmanned vehicles or equipment and use a scramjet with booster rockets for the astronauts."

That would work, but as scramjet spaceplanes aren't available yet, you could use a conventional rocket. The only drawback I can see is that the manufactured components or modules of the vehicle to be fully constructed in orbit would have to have a higher structural strength than they would if launched conventionally, and this would probably result, even with new materials, in them having a higher mass on launch. However, if the the maglev launch rail is cheap, then the extra cost might be reduced or irrelevant.

Posted on Oct 13, 2009 2:52:03 PM PDT
D. Kneeland says:
That is true. That and I suppose the adjustments needed to facilitate that assembly of large modular components in a microgravity environment would impose a rather large initial investment as well. This is obviously something that would not start tomorrow, but being able to do something like this might ultimately become necessary if we are going to make it to the point that manned missions throughout the solar system are routine.

Posted on Oct 14, 2009 9:07:17 AM PDT
To anyone still following this discussion, you may want to check out the following links:

http://www.eetasia.com/ART_8800514914_499501_NT_11f326ed.HTM

This is a 2008 article titled "Superconductors Enable Magnetic Flux Pinning For Spacecraft". ("Cornell University researchers propose that superconductors paired with permanent magnets could enable spacecraft to hover unpowered above the ground ...")

http://www.manep.ch/en/technological-challenges/emfields.html

This is a Swiss article with a great background discussion on Superconductors and Magnets.

http://superconductors.org/index.htm#top

This is apparently the "Go To" site for the latest on Superconductors.

http://news.ufl.edu/2002/11/20/newsuperconductor

This is a 2002 article out of the University of Florida, about their discovery of a new superconducting substance. ("To their surprise, a probe of (plutonium's) magnet properties revealed diamagnetic or 'anti-magnetic' behavior, a telltale indicator of superconductivity.")

In reply to an earlier post on Oct 14, 2009 11:18:52 AM PDT
M. Helsdon says:
"This is a 2008 article titled "Superconductors Enable Magnetic Flux Pinning For Spacecraft". ("Cornell University researchers propose that superconductors paired with permanent magnets could enable spacecraft to hover unpowered above the ground ...")"

http://www.eetasia.com/ART_8800514914_499501_NT_11f326ed.HTM

This is another web tabloid severely stretching the truth...

The reality was described in the May 09 2008 issue of Superconductor Week (which is not a tabloid but a scientific newsletter providing global coverage of the technology and commercialization of low- and high-temperature superconductors and cryogenics).

http://superconductorweek.com/cms/

Flux-pinning does NOT "enable spacecraft to hover unpowered above the ground".

Cornell University received about $100,000 from Northrop Grumman to develop modules consisting of magnets and flux-pinning superconductors to maintain the position and orientation of spacecraft components over a very short distance (about one meter) to facilitate the assembly of these components together in microgravity.

The system is intended to maintain the relative position between modules, not to act as a form of 'antigravity'.

In reply to an earlier post on Oct 14, 2009 7:39:47 PM PDT
Ronald Craig says:
Oh, one anti-something is as good as another, isn't it? :P

Posted on Oct 15, 2009 1:39:34 AM PDT
D. Kneeland says:
M. Helsdon says:
"The system is intended to maintain the relative position between modules, not to act as a form of 'antigravity'."

Awesome! That solves one of the problems I was thinking about in my last post about the issues of assembling modules in space. It seems to be a cheaper and easier solution to implement then anything I was thinking of. Though this may also be one of the reasons why I don't get paid the big bucks to do so either.

Posted on Oct 16, 2009 8:04:43 AM PDT
To anyone still following this discussion, below are some links to research on magnetic levitation and plasma:

http://www.apam.columbia.edu/mauel/mauel_pubs/Turbulent_Diffusian_APAM09.pdf

This is a Research Paper titled "Diffusion of Plasma in Magnetic Fields" (9/11/09) Several of their conclusions are "The mechanics of magnetic levitation is proven reliable." And "... has demonstrated the formation of natural density profiles in a laboratory dipole plasma and the applicability of space physics to fusion science."

http://psfcwww2.psfc.mit.edu/ldx/

This is MIT's paper on "The Levitated Dipole eXperiment"

http://jjap.ipap.jp/link?JJAP/40/L1029

This is a Japanese physics paper from Aug.'01, titled "Levitation Experiments Using A High-Temperature Superconducting Coil For A Plasma Confinement Device"

In reply to an earlier post on Oct 16, 2009 10:45:58 AM PDT
M. Helsdon says:
"To anyone still following this discussion, below are some links to research on magnetic levitation and plasma"

Magnetic levitation is a well understood phenomena, and these are all valid and interesting items of research in this field. But: again, magnetic levitation is not 'antigravity'.

In reply to an earlier post on Oct 16, 2009 11:21:18 AM PDT
Ronald Craig says:
Marilyn Martin did her thing again:
"http://jjap.ipap.jp/link?JJAP/40/L1029

This is a Japanese physics paper from Aug.'01, titled 'Levitation Experiments Using A High-Temperature Superconducting Coil For A Plasma Confinement Device'"

Do you subscribe to the Japanese Journal of Applied Physics, Marilyn? I don't, so all I could see was the abstract:

"Levitation experiments using a high-temperature superconductor coil have been carried out. A coil with a minor radius of 42 mm was fabricated with a Bi-2223 tape conductor, and immersed in the liquid nitrogen. The coil current was induced by the field-cooling method up to the critical current value. The current decay of the coil can be accounted for by the flux flow resistance and the normal resistance at the lap joint. The high-temperature superconductor coil can be levitated for 4 min or more within an accuracy of 25-30 µm."

Wow! This is really relevant!

In reply to an earlier post on Oct 16, 2009 11:42:18 AM PDT
B. A. Dilger says:
Didn't the Chinese build a mag-lev train from Shanghai (or whatever in Pinyin) airport to the city? I know the Germans had an experimental one. They can't quite clear a foot of Earth gravity. What does a watch-sized superconductor coil do when it "levitates"? Like a Persian carpet in "1,001 Arabian Nights"?

In reply to an earlier post on Oct 16, 2009 12:11:56 PM PDT
M. Helsdon says:
B.A. Dilger,

"Didn't the Chinese build a mag-lev train from Shanghai (or whatever in Pinyin) airport to the city? I know the Germans had an experimental one. They can't quite clear a foot of Earth gravity."

The first was in Birmingham, UK, in 1984, but being the first it suffered technical problems and was eventually replaced. The Germans built a more successful system in Shanghai, and there have been others in Germany, Japan, Korea and the USA. Clearance tends to be in fractions of an inch.

In reply to an earlier post on Oct 16, 2009 1:14:03 PM PDT
oldmaol says:
1. By your definition of "knowing" we don't know anything because we don't know everything. We do actually know quite a lot about gravity thanks to E, and it's far from trivial.
2. We know exactly as much about magnetism as we do about electricity because they are the same phenomena. The "particles" that "Stretch"??? between magnets are called PHOTONS which are the carriers of the electromagnetic force. (By the way someone referred to gravity and magnetics as "energies". They are forces.)
3. We certainly can create gravity. Just pile up a big mass and voila! Also the big E says any acceleration of a mass creates forces that are indistinguishable from gravity (such as that centrifuge).
4. We can imagine warping space in only one way (ie with mass) and a large warp is produced by a black hole. We cannot imagine slipping through a black hole, and even though worm holes have be postulated using some mathematical speculations (most of these involve very large masses also), they do not start or end in reality, and no one has attempted to say how one could travel through one.
5. Why are you amused with the gravity in Star Trek but not all the other ridiculous magical events (e.g. Q, the mist the ship goes through in the preamble, the holodeck with physical effects, etc.).
5. Please, please, please don't ever mention anything religious or you will have the "creationists/intelligent designists" down on us, and then you will see some real ranting.
6. There are many theories about gravity (mediated via gravitons) but the particles are all (so far) too heavy to be detected by our science. The LHC may have something to say on that if it ever gets on line.
7. Many theories also use extra dimensions to assist in explaining how gravity fits into the quantum world. None of these, however, says these dimensions are anything like our spacial dimensions, but are all curled up so small that they cannot be observed. All science is waiting for any evidence that will allow us to select which of these ideas has physical validity.

In reply to an earlier post on Oct 16, 2009 2:21:57 PM PDT
M. Helsdon says:
oldmaol,

"6. There are many theories about gravity (mediated via gravitons) but the particles are all (so far) too heavy to be detected by our science."

If I understand you correctly: Hypothetical gravitons are potentially massless and operate over a 'long distance', and so are too 'light' to be easily detected (and we haven't yet even detected theoretical gravity waves).

Posted on Oct 30, 2009 9:03:38 AM PDT
To anyone still following this discussion, I found an (admittedly) religious-fringe site, with a very interesting article with multiple embedded links:

http://100777.com/node/1146 - "A Summary Of A Search For Free Energy and Anti-Gravity On The Internet"

Cheers!

In reply to an earlier post on Oct 30, 2009 11:58:44 AM PDT
M. Helsdon says:
"http://100777.com/node/1146 - "A Summary Of A Search For Free Energy and Anti-Gravity On The Internet""

A few real items there which have nothing to do with 'Free Energy and Anti-Gravity' but the rest are all variants on the old perpetual motion machine/perpetual energy fakes and simply won't work in the way described. No free energy will be generated, and no antigravity effects produced.

In reply to an earlier post on Oct 31, 2009 12:13:51 AM PDT
Ronald Craig says:
Zero capacity to learn.

Posted on Nov 1, 2009 8:41:36 AM PST
To anyone still following this discussion, below is a link to a recent article in the respected Christian Science Monitor.

http://features.csmonitor.com/connectingthedots/2009/10/27/beond-ares-1-x-the-problem-with-long-term-space-missions/ (BEYOND ARES 1-X: THE PROBLEM WITH LONG TERM SPACE MISSIONS - October 2009) Discusses the "problem" of gravity, and has a link to their "Monitor Special Report" on spaceflight.

Posted on Nov 1, 2009 5:05:05 PM PST
Doug says:
ya know? I have to wonder about anti-gravity drive, even tho it seemed to be the engine of choice for Klatu and for J J Adams in the C-57D.
However --
Like most other forces, the strength of the force is inversely proportional to the square of the distance between objects, and it seems to me that an anti-gravity engine would run out of "steam" somewhere in the void between solar systems with which it could slingshot off or around. I would guess travel between galaxies would be worse yet, not to mention the fact of the time involved.
Again, we seem to be left with warp drive as the propulsion of choice; provided either biologically as in DUNE, or mechanically, as in StarTrek.
Anti-grav drive would be handy inside a solar system like a trolling motor on a fishing boat, but I think we would still need the supercharged Big Block to handle the longer trips and shorten the time it takes to make 'em...
Maybe we could hook up a kleistron tube to a dilithium converter and git r done???
Whatcha think?
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Initial post:  Jul 17, 2009
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