This is what the Northern Lights, or the “aurora borealis”, might look like. They are glowing streaks of color that light up the northern skies. In the southern hemisphere, above Antarctica, a similar lightshow is known as the "aurora australis”. I’ve never read a simple explanation on how this phenomenon occurs, so I thought I’d attempt one:

The earth has a magnetic field that deflects streams of charged particles that spew from the sun. Solar winds emit a constant flow of these charged particles (in essence, electric currents), which are released out into the solar system. Occasionally, a much larger burst of energy is produced by solar flares. When any of these charged particles from the sun reach the earth, the magnetic field (in the earth’s magnetosphere) either deflects them around the planet or channels them toward the North and South Poles.

The aurora is caused when these high-energy particles collide with the gas particles in the earth’s outer atmosphere around the poles (very much like the beams of electrons that strike the phosphorous screen of a television set). The colors of the aurora are determined by both the altitude of the particle interaction as well as which gases are involved. High-energy collisions with oxygen, for example, produce green lights; low-energy collisions with nitrogen produce violet lights (very much like neon tube lighting, which use different gases to produce different colors.)