[dogma1138]

There is sufficient data about it, electromagnetism is probably the best studied field in physics to date. Magnetism is in it's base not generated due to the modulation of an electric charge but due to a much more basic attribute of charged particles, their magnetic moment which is a result of their spin. https://en.wikipedia.org/wiki/Spin_magnetic_moment So until you find a zero spin charged particle with a magnetic moment (which will contradict everything we understand about magnetism) I'll bet on that we understand it quite well.

As far as UFO's using the Earths magnetic field we can pretty much rule that out because we know just how weak it is on average it is about 30 Tesla, and 16 Tesla's is about the force required to levitate a frog. https://www.newscientist.com/article/mg15420771.600-frog-def...

So unless flying saucers weight just about as 2 mid sized frogs I'll take the bet that if they do exist they use something else to keep them from crashing in the backyards of hillbillies.

[nonbel]

"Earths magnetic field...is on average it is about 30 Tesla, and 16 Tesla's is about the force required to levitate a frog...So unless flying saucers weight just about as 2 mid sized frogs I'll take the bet that if they do exist they use something else to keep them from crashing"

Something about this doesn't make sense. Probably has to do with the answer to this question: Why don't frogs normally float due to the Earth's magnetic field?

[FiatLuxDave]

This is incorrect. The Earth's magnetic field is about 30 microTesla, not 30 Tesla. Also, the flog floating effect (one of my old profs actually did that experiment!) depends upon the field gradient as well as the field strength.

Field strength is not the same as force. The reason why they don't levitate things bigger than frogs with a 16 Tesla field is because bigger things won't fit into the magnet bore, not because 16 T is too weak. One of the techs who worked on one of those serious magnets (at NHMFL) told me that if they put an iron bar in the middle of the bore, it would generate enough force to lift a 747. Of course, that much force would probably break the floor under the magnet, and it's really hard to fit a 747 into the lab.