Northern Lights

In April 1991 the space shuttle Discovery photographed this display of the aurora australis, or southern lights, over the Antarctic region. From above, you can see the magnetic field lines, a series of vortices in the Earth's magnetic field, along which electrons and protons move as they burst into the atmosphere. When space weather pours energy towards Earth and energizes its magnetic field, particles flow and collect at both ends of these field lines, culminating in 2,500-mile-wide rings encircling each pole.