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Building a Miniature Magnetic Earth
Doofus writes "There was an interesting story on NPR this morning about a geophysicist who has constructed a miniature earth to model the earth's dynamo effects.
Dan Lathrop, a geophysicist at the University of Maryland, has constructed a 10-foot diameter stainless steel sphere. He intends to fill the sphere with molten sodium and spin the sphere to examine the propensity for the system to generate its own magnetic field.
The article includes both video, in which Lathrop spins up the sphere, and audio, including the conversion of magnetic wave functions in prior experiments into audible sound: literally the music of the spheres."
For many types of fires, including reactive metal fires, best procedure is to just let it burn if possible. In this case, I imagine you'd build the setup so that that *was* possible, and then focus your efforts on making sure you could get everyone out of the way efficiently. A huge pool of burning sodium is certainly dramatic, but if there's no person or property in danger then there's no necessarily anything wrong with it. The caustic lye dust should fall out of the air rapidly; don't stand down wind.
When it comes to exotic fires, there are techniques to fight them -- but by far the preferred one is to not fight it at all. Besides, suppose you did put it out -- you now have a damaged sphere of molten sodium that already caught fire once. Are you planning to approach it? I'd rather stand back and wait for it to go out if at all possible.
I'm sure they've informed the fire department, and I'm sure the fire department intends to get involved only if there's an immediate danger to life, or a risk of the fire spreading -- in which case they'll likely try to contain it without putting it out.