Jed,
Geomagnetic propulsion is based on the use of the earth's magnetic field as
a force field analogous to the stator of an electric motor. Each such motor
corresponds to the rotor of a conventional electric motor, propelled by
interacting force fields as instructed by a computer.
The patented Free-Flying Magnetic Levitator, as well as more recent designs,
make use of the very weak geomagnetic field. Geomagnetism averages a mere
.5 gauss in magnetic field strength. At first glance it seems impossible to
power any kind of vehicle by interaction with this weak field.
However, it is useful to imagine that the interaction of two magnetic fields
exists at those points where the densities of the fields involved are equal.
In effect, it is as through the small artificial field source expands
itself into a huge magnetic balloon, because of the low density of the
earth's magnetic field. Cohering the seemingly insignificant forces that
act upon every point on the surface of the balloon, yields a considerable
resultant force. It is this surprisingly large force that can be harnessed
to propel an air or spacecraft.
An analogy is the well known passenger carrying balloon. The differential
air pressure on any square inch of the balloon's surface is very small.
But, the large area provides substantial lift.
Ultraconductors provide extremely high current density. Once they are
available as wire, with adequate funding in about three years, they will be
an ideal material for the windings of motors that can provide geomagnetic
propulsion.
Mark
From: Jed Rothwell <[EMAIL PROTECTED]>
Reply-To: [email protected]
To: [email protected]
Subject: Re: A low cost alternative to the space elevator
Date: Fri, 04 Nov 2005 10:25:44 -0500
Mark Goldes wrote:
MPI has been supporting How Wachspress, an inventor who holds a Patent and
has done many experiments that suggest a free-flying magnetic levitator
can become practical, and provide a better path to access to space.
A levitator can be designed to take off and land at ordinary airports,
using the geomagnetic field as the stator of a very clever electric motor.
The geomagnetic field? 0.6 gauss at the maximum? That's preposterous. As
Clarke wrote in "Profiles of the Future:"
"The Earth's magnetic field is so extremely feeble (a toy magnet is
thousands of times stronger) that it is not even worth considering. From
time to time one hears optimistic talk of 'magnetic propulsion' for space
vehicles, but this is a project somewhat comparable to escaping from Earth
via a ladder made of cobwebs. Terrestrial magnetic forces are just about as
tough as gossamer."
You would have to have a ship that reacted against the field with a plate
of hundreds of square kilometers, and the plate would have to weigh a few
kilograms.
- Jed
