Where and when can you see it?

The northern lights are a belt — a crown of light encircling the planet's magnetic poles. You have to step beneath that crown.

Aurora Borealis appears in the north; Aurora Australis in the south. Because the seasons are opposite in the two hemispheres, it is impossible to watch both on the same day — except in the equinox months, September and March.

Two faces of one mirror — not quite.

Until 2009, science assumed the lights seen in the north had an exact copy forming in the south. Later discoveries showed that the Sun's rays interact differently along the east–west axis at the magnetic poles: at the two poles the auroras appear in different regions and in different shapes.

It has also been found that this “asymmetric” formation eases — producing symmetric displays — in the moments when the two poles communicate through the magnetic tail.