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Experimental Magnetic Shield Against Cosmic Rays
stiller writes "British scientists from the Rutherford Appleton Laboratory have developed an experimental set-up in which a $20 magnet is used to deflect solar-wind-like radiation." Reader Dersaidin points out a slightly more enthusiastic article at Universe Today which emphasizes the possibilities of systems based on this phenomenon to protect astronauts during solar storms, writing
"It's a good start. Hopefully, later versions will be able to protect spaceships from energy weapons. A beam from the LHC can melt a 500kg block of copper. Shields, check. Energy weapons, check. Now we just need a viable interstellar drive, and an energy source to power it all."
Did anyone else misread the title?
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
I suggest mounting a standard generator at the core of the prospective space ship and attaching a coffin containing one of our founding fathers to it. The rapid spinning should provide plentiful power for all manner of techno-gadgetry.
According to TFA this thing uses about as much energy as an electric kettle, Does this mean British astronauts will need to choose between the two? I can see it now, a mustachio'd astronaut (in my mind I imagine him an old RAF captain) hovering over the button and staring at the kettle. Agonizing over the decision before muttering 'To the Queen' and putting the kettle on.
This brings up a larger issue to me...how well does tea steep in zero G, And would there be a difference between an Earl Grey blend or a black tea blend?
-=Bang Bang=-
No hope of becoming one of the Fantastic Four. Bummer.
From Instructor: Now we're going to practice our impact procedures. Ok everyone lean to the left.
*Whole class but one guy leans to the left*
From Instructor: Good! Now lean to the right.
*Whole class but same one guy leans to the right*
From Instructor: Excellent! Your prepared for when the ship takes damage.
From The One Guy: Uh? Why are we leaning to the left and right like that?
*Instructor hands him a red shirt*
From Instructor: Keep your insurance paid up son.
~~ Behold the flying cow with a rail gun! ~~
A beam from the LHC can melt a 500kg block of copper.
Technically, if things are set up, any continuous source of energy can melt just about anything meltable. Just keep the energy flowing, insulate the target, and if the temperature of the energy source (e.g. a lightbulb) is higher than that of the target, then energy will couple in and eventually melt the target. What needs to be mentioned if such a statement is to be of any use, is how long such melting is expected to take.
You only need to protect the occupants and sensitive equipment. You can just put the ramscoop out ahead of the magnetic protection field.
up next: Monster Gold Diamond HDMI cables with Cosmic Ray protection.
According to this CERN page, in the few microseconds that it takes a beam dump to complete. The circulating kinetic energy of the beam is an impressive 350 MJ, equivalent to running a 1000 watt heater for 97 hours.
There is no sequel. There can be only one.
What needs to be mentioned if such a statement is to be of any use, is how long such melting is expected to take.
That's a very good point, and to answer the question raised by it I RTFAed so you don't have to! Regarding the "dump block" that they use to absorb the LHC beam before it becomes unstable:
Emphasis added. That's one hell of a beam.
BTW, I can't help but recall that the Enterprise D from ST:TNG fires its phasers from a large ring on the saucer section. You can almost imagine the LHC being weaponized and using the same technique that diverts the beam into the dump block to direct it outward towards enemy ships. Though it'd have the rather significant drawback that any damage anywhere on the enormous accelerator ring would take out the weapon. But hey, energy beam!
The enemies of Democracy are
reposted from below (with corrections) in the comments, since my comment belongs here in response to your comment:
.15 cm * 4000 cm == 600 cm^2.
.86 microsecond beam burst.
FTA, testing showed a 1.5 mm beam "burnt" 40 meters into a block of copper in 86 microseconds.
So... napkin calculation...
density of copper is about 9 g/cm^2, so 5600 grams of copper melted per
500 lbs =~ 227 kg, so roughly forty 86 microsecond bursts to melt 500 lbs...
So we're talking roughly 3.5 milliseconds to melt 500 pounds of copper.
That's 70 tons of copper melted per second for a single beam. That's a hell of a lot of energy, but I'm not sure what the standard unit is for energy/time (hiroshimas is just energy; libraries of congress and football fields obviously don't apply). Anyone know what the standard made-up unit is for energy/time?
"Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
And the one thing people keep forgetting: a power source. Or are we going to have the crew constantly peddling a bicycle to generate electricity? Which raises a question no one seems to be able to answer; do we need to deflect cosmic rays and solar radiation, or absorb it for use as energy to power the ship's tech?
I dream of a better world... one in which chickens can cross roads without their motives being questioned.
Anyone know what the standard made-up unit is for energy/time?
Sadly, we don't need a made-up unit for that. The one we have is bad enough:
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I am the richest astronaut ever to win the superbowl.
so if you slashdot their site do you win?
ah... found it on SourceForge
"Hoover Dams" are the units used to represent such things as the power output of the Shuttle main engines. Other popular ones are "enough to light N,000 homes" and "equivalent to N nuclear power stations" (always nuclear, for some reason).
Melting copper takes 13.050 kJ/mol. A mole of copper is 63.546 grams. We'll drop everything to two significant figures, which is probably already more precise than the rest of the numbers. 70 tons is one million moles, so melting 70 tons per second is 13E12 J/sec, 13 terawatts, which is close enough to the 10 terawatt figure for the beam dump that's on the web. Five or six thousand Hoover Dams, then.
I was looking for a serious thread to reply to, but it seems this topic attracts more kidding than science. =p
Anyway, my college plasma physics professor, a decade ago, told us that he'd invented the "force field". It created a magnetic shield around an object in a vacuum, and was intended to protect things like satellites from charged particles. (For obvious reasons discussed below he didn't go into detail.)
His work was funded by the U.S. Air Force, who promptly took the patent and classified it. In other words, this was invented about 15 years ago, and this guy might have just made it public, but he's likely not going to get a patent to protect his invention since it will be rejected.
It doesn't hurt to be nice.
Uh, some math errors exist in some of the parent posts.
A 1.5mm diameter beam that is 40 meters long has a volume given by:
V = pi * r^2 * d
If r and d are in cm, then:
V = pi * (0.15/2)^2 * 400
V = pi * 0.005625 * 400
V = 7.07 cm^3.
At 9 g/cm, this gives a mass of 63.2 grams.
If we're melting/vaporizing this much in 86 uS, that gives a rate of
63.2 / 0.000086 = 734,883.72 g/s (or 1,620.14 lb/s).
It's still a bunch of melted (actually, vaporized) copper, but it's nowhere near 70 tons.
All the above assumes that the beam stays perfectly coherent and doesn't have any losses due to heating of surrounding material. In reality, the beam would rapidly diverge, and heat would begin to flow through the copper. Oh, also, ejected copper plasma would at some point begin to interfere with the beam itself before it reached the copper itself. This would rapidly de-focus the beam and absorb energy, so the plasma ejecta would get oh-my-god hot while shielding remaining copper from being damaged.