Hi all.

I think we have all had fun looking at ways to raise an orbit and the answer seems to be, from the basic physics, that you will exert an extremely small force the effectiveness of which is dependant on the distance between the poles and the strength of the magnet, and some other things too

However, to put this into perspective...........AO-51, which we all know and love, uses a similar principle for attitude stabilisation. Instead of repelling the space craft into outer space the magnet on board causes the spacecraft to rotate one turn per orbit. This ensures that over the northen 'pole' the antenna end of the spacecraft points straight down. Over the southern pole the antennas point in the other direction. (sorry southern hemisphere) - for those of us living between 50N and 50S it also allows us to predict whether we will get better signals (particually on 2.4G) as the spacecraft approaches or moves away from us. By knowing the attitude we know if the antennas are pointing towards us or not.

Of course, what does not happen with AO-51 is that force of attraction from its magnet does not cause any measurable deteroration in the orbit. i.e. AO-51 does not show any tendancy to dramtically spiral down and crash into the earth.

why? well imagine the forces involved. 1) you have the kinetic energy of a 20kg (?) spacecraft travelling at 18,000MPH. That's a lot of energy. - difficult to imagine....OK Just imagine 20kg hitting the side of your house at that speed....Yes, thats a lot of energy!

compared to.

2) The force of a magnet with the poles 1 foot apart 1.5 million feet from the ground.

Not sure if that helps. But it did make me understand how something with so much energy due to its velocity can be easily rotated on its own axis by a magnet, but not have its direction of motion changed by a that magnet.

tnx

David G0MRF

In a message dated 22/02/2007 07:32:52 GMT Standard Time, ojwanga2@asme.org writes:

The craft could push-off the magnetic field of the planet, using it as a rail.

Andrew. KI4LTH/5Z4FT.