A while back in relation to the space elevator a concept of a plasma bubble developed by a group at Washington University was discussed. A version of this same concept is being worked on by a second group of the same University. Think back to 1984 and a mission called the AMPTE (Active Magnetospheric Particle Tracer Explorer). A satellite, one of three, was designed to study the basic physics of plasmas and produced a cloud of it which then protected the satellites from solar wind. This mission did not test containing the plasma to see extended protection and just allowed the cloud to dissipate.
There is one thing that I am curious about. This plasma bubble developed requires a conductive mesh to envelope the protected object. While I can see this in a spacecraft, it doesn’t fully make sense for an astronaut, unless I am being too literal and the mesh can be an actual material – perhaps a meta-material? The bubble has many unknowns and while is being looked at by one group for spacecraft-protection, it has never been tried on that large a scale, but in looking at an astronaut suit, it is only slightly larger than the satellites and has a greater chance of working. So one day, maybe sooner than you think, Magnetic Deflector Shields could protect the astronauts on their lengthy missions to the Mars, perhaps a colony on the moon etc.
While this concept is effective against the Sun, there is a lot NASA still does not know. Things like will it protect the astronaut from Cosmic Rays, how big IS the health risk, and so on. Another problem would be understanding what would occur if it were to break – either the material or the plasma generator. NASA loves redundancy and back up plans and rightly so. Space is not forgiving and certainly is not the place to say ‘Whoops!’