Uhhh, no. First the magnetosphere is an area of influence around the Earth caused by the Earths magnetic field and provides a "shield" from highly charged and dangerous particles that emanate from our sun. Second, there is evidence that the Earths magnetic field (caused by the motion of the Earth's molten core) once 'flipped' but IF that is going to happen again, its still a long way off. Its not sure that it will, and prediction of that is like prediction of global warming, based on models that may or may not be correct.