Suppose we suspend a spherecal magnet (is that possible?) in a high vaccuum in 0g and throw a ball bearing at it.
Is it possible for the BB to settle into a stable orbit? Not a gravitic orbit, but a magnetic one.
Magnetism is a much stronger Force than Gravity, and very quickly dissipates over distance. The balance between orbit speed and distance would be extremely difficult to obtain, much less, maintain. Also, movement through the magnetic field would induce a field in the satellite. Even with a very weak magnet, the interaction of the fields would quickly degrade the “orbit”.
At least, that is my guess.
rwj
I believe the problem is that gravity is monopolar (it only pulls) but magnetism is dipolar (it attracts or repels, depending on the side of the magnet). I doubt you’d find a stable orbit around a magnet of any shape.
Interesting point. If the ball bearing were placed near the center of a very long magnet, would it be attracted to a pole, or straight toward the magnet?
rwj
Interesting point. If the ball bearing were placed near the center of a very long magnet, would it be attracted to a pole, or straight toward the body of the magnet?
rwj
Gravitational forces generally fall off as 1/r[sup]2[/sup], while magnetic forces fall off as 1/r[sup]3[/sup] or more. Because of this, it’s possible to have a closed circular orbit (as it is for any central force), but the orbits are not stable: Any perturbation will cause the orbiting object to spiral either inward or outward.
It would be a delicate orbit!
there is some path through the magnetic field where the attractive force is constant so it would be possible. It wasn’t my first guess though.
If it were near the center, it would be more attracted to the side that it was slightly closer to, and thus be pulled that way. Theoretically, if it were precisely at the center, it would be pulled equally in both directions, and thus be held in place. Realistically, I think that would be really hard to do.