Scientists at the Rutherford Appleton Laboratory in the United Kingdom are working on an artificial magnetosphere that could protect astronauts on a mission to Mars.
Long duration space flights present a special problem: the charged particles of the solar wind are extremely dangerous to the health of astronauts. On a trip to Mars, astronauts would be exposed to this radiation for months. Heavy shields on the craft would be enormously expensive to lift into space, but what if we could create a miniature magnetosphere, like the one that protects us here on Earth?
The research is still in its early stages, but it's looking like creating a little magnetosphere for a spacecraft is not as daunting as was once thought. You don't need a giant molten iron core... a modestly-sized electromagnet might just do the trick. It turns out that these sorts of small magnetic shields are more common than we thought... even some asteroids have been shown to have them. And as NewScientist explains, the magnetic field doesn't need to be all that powerful:
Some parts of the solar wind shift more easily than others. The positively charged protons have nearly 2000 times the mass of the negatively charged electrons, so the latter are much more easily deflected. The electrons stay at the surface of the magnetic bubble, while the positive charges penetrate further in.This separation of positive and negative charges generates intense electric fields up to a million times stronger than the magnetic fields that created them. Subsequent solar wind particles hit these electric fields and are strongly deflected. The result is a shielding effect far more powerful than the magnetic field alone might be expected to provide.
We're still a ways from seeing these force fields utilized on spacecraft. But this work brings us one step closer to making a mission to Mars a reality. Very cool.