I'm wondering if, using enough neodymium magnets (dont worry where the material is coming from) in a low martian orbit, could you produce a powerful enough magnetic field to protect the atmosphere from burning away? How would this impact interplanetary travel? How much maintenance would it take per decade?
If you want to protect a planet from the solar wind, the scale of the magnetic field has to be comparable with the one of the planet. A magnet, no matter how strong, has its field decay with the cube of the distance.
Magnets orbiting the planet would do little to no benefit, unless you can have a magnetic bar going from pole to pole through the planet.