Magnetic reconnection occurs wherever magnetic fields clash. As the fields try to bend around one another, the field lines break and recombine like a short-circuit in space, sending out jets of electrons and ions moving at speeds of hundreds of miles per second. In addition to these jets, the process also is thought to produce much more energetic electrons, with energies up to hundreds of thousands of electron volts - equivalent to a speed of more than 100,000 miles per second. This highly energetic process is thought to occur in explosive solar flares, generating electrons with energies ranging from tens to hundreds of thousands of electron volts that carry away as much as half the energy in the flare. When the magnetic fields of the Earth and sun interact and reconnect, particles from the sun spiral along magnetic field lines slide like beads onto the Earth's field lines, eventually making their way to the poles and generating the aurorae.

Aurora Borealis, courtesy John Russell