An aurora seen from Earth

On our planet, as well as on the giant planets Jupiter, Saturn, Uranus and Neptune, aurorae occur at the foot of the planetary magnetic field lines near the poles, and are produced by charged particles – electrons, protons or ions – precipitating along these lines.

This aurora was seen from Fairbanks, Alaska. The dark band in the green aurora pictured here is an example of a black aurora. A black aurora isn't an aurora at all; rather it is a lack of auroral activity. The black aurora is only visible to the naked eye if it is embedded in a region of diffuse (faint) aurora.