Superconductors, Orbits, Magnetic Field
I recently learned about Superconductor and Meissener
When superconductor meets low temperature, its electricity resistance
becomes zero, thus when the Superconductor receives magnetic energy, it
reflects back same amount energy that it can levitate a magnet on the
superconductor. We know that Earth itself is big magnet and contains
magnetosphere.Then superconductor itself should be levitated from the
ground because it reflects back the same amount of magnetic energy
received, but it does not happen you know.
How about in outer atmosphere, like low orbit 200km altitude?
Would superconductor move away from the earth?
Interesting question. The superconductor will generate a magnetic field
through the Meisner Effect even in the relatively low magnetic field of the
earth. Earth's magnetic field is around one gauss or even less, away from
the magnetic poles of the earth. The magnetic field generated by the
superconductor would not exceed that of the magnetic field of the earth and
this is just not enough energy density to levitate. If the superconductor
were in orbit then the magnetic field from the earth would be smaller since
one is moving away from the source of the field. This would in turn lead to
less energy than on the earth. Just to add one more point, not exactly
directly related to your question. Magnetic fields are used to propel
projectiles. This type of propulsion device was devised more than 40 years
ago at MIT.
Dr. Harold W. Myron
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Update: June 2012