Aurora australis, the southern polar lights
Aurora borealis, the northern polar lights

The light show comes to us courtesy of our Sun. Electrically charged particles produced on the Sun are ejected in all directions and a great amount of them head toward Earth. As these particles (called solar wind) encounter the Earth’s outer regions, the magnetic field of the Earth begins to interact with the particles.

What results is a change in energy and direction of the particles: they head along magnetic field lines toward the poles of Earth. Just like a bar magnet has its field lines returning at the opposite ends so the Earth’s magnetic lines come together around the poles. This is why the aurora borealis is brightest and most easily seen in the northern regions of our planet.

Most auroras are green and red emissions from atomic oxygen. Molecular nitrogen and nitrogen ions produce some low level red (pink) and very high blue/violet auroras. The light blue and green colors are produced by ionic nitrogen and the neutral helium gives off the purple colour whereas neon is responsible for the rare orange flares with the rippled edges. Different gasses interacting with the upper atmosphere will produce different colors, caused by the different compounds of oxygen and nitrogen. The level of solar wind activity from the Sun can also influence the color and intensity of the auroras.

The light show comes to us courtesy of our Sun.  Electrically charged particles produced on the Sun are ejected in all directions and a great amount of them head toward Earth.  As these particles (called solar wind) encounter the Earth’s outer regions, the magnetic field of the Earth begins to interact with the particles.

What results is a change in energy and direction of the particles: they head along magnetic field lines toward the poles of Earth.  Just like a bar magnet has its field lines returning at the opposite ends so the Earth’s magnetic lines come together around the poles.  This is why the aurora borealis is brightest and most easily seen in the northern regions of our planet.

Most auroras are green and red emissions from atomic oxygen. Molecular nitrogen and nitrogen ions produce some low level red (pink) and very high blue/violet auroras. The light blue and green colors are produced by ionic nitrogen and the neutral helium gives off the purple colour whereas neon is responsible for the rare orange flares with the rippled edges. Different gasses interacting with the upper atmosphere will produce different colors, caused by the different compounds of oxygen and nitrogen. The level of solar wind activity from the Sun can also influence the color and intensity of the auroras.