While many hurdles are keeping us stuck here on Earth, our solar system's deadly radiation is chief among them. But scientists now think that a thumb-sized magnet could produce a force field big enough to shield an entire spaceship.
The big fiery ball we call our Sun is constantly shooting high-energy particles out into the solar system, a solar wind that yields radiation some 1000 times more powerful than that of the atomic bomb dropped on Hiroshima. The Earth's magnetosphere, produced by our planet's molten iron core, deflects the solar wind from our rock and protects our bodies from that radiation.
Scientists once thought a prohibitively huge magnet would be necessary to produce a similar, spaceship-sized shield, but a British lab has found that a small magnet is sufficient to create a magnetic field powerful enough to deflect a significant amount of the charged particles. The phenomenon occurs because of a unique reaction between the solar wind and the magnet:
Because the solar wind is a plasma made up of charged particles, it too carries a magnetic field. When the solar wind's field meets the rocks' mini-magnetosphere, the two fields clash, exerting a force on each other. Something has to give. Because the solar wind's field is created by free-moving particles, it is the one that yields, altering its orientation to minimise conflict with the mini-magnetosphere's field.
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.
Sceptics worry that the higher-energy particles found in space would blast through such a shield, but the Rutherford Appleton Lab, which made the discovery, is already in confidential talks with NASA to determine the implications of their find. For more force field fodder, check out the full article at New Scientist. [New Scientist]