A NASA-sponsored researcher at the University of Iowa has developed a way for spacecraft to hunt down hidden magnetic portals in the vicinity of Earth. These portals link the magnetic field of our planet to that of the sun. Physicist Jack Scudder said the portals are:
… places where the magnetic field of Earth connects to the magnetic field of the Sun, creating an uninterrupted path leading from our own planet to the sun’s atmosphere 93 million miles away.
This NASA ScienceCast has more.