Facts About the Northern Lights

Auroras happen when charged particles from the Sun are funneled by Earth's magnetic field toward the poles, where they collide with gases in the upper atmosphere and make them glow.

The aurora's colors come from different gases and altitudes: oxygen produces the common green (and rarer high-altitude red), while nitrogen contributes blues, purples, and pinks.

The southern hemisphere has its own version — the aurora australis — which mirrors the northern lights around the south pole.

Auroras typically occur between about 100 and 640 kilometers (60–400 miles) above the ground — far above where airplanes fly.

The best viewing sits under the 'auroral oval': northern Norway, Sweden, Finland, Iceland, Greenland, northern Canada, and Alaska.

The name 'aurora borealis' — from Aurora, Roman goddess of dawn, and Boreas, Greek god of the north wind — is commonly credited to Galileo in 1619.

Auroral activity follows the Sun's roughly 11-year cycle; around solar maximum, displays become more frequent and reach farther from the poles.

In May 2024, the strongest geomagnetic storm since 2003 pushed auroras to extraordinarily low latitudes, with sightings reported across much of the United States and Europe.

Space weather agencies rate geomagnetic storms with the Kp index (0–9); the higher the number, the farther from the poles the aurora can be seen.

Auroras aren't unique to Earth — spacecraft have photographed them on Jupiter and Saturn, whose magnetic fields also channel charged particles.

Strong geomagnetic storms can disrupt satellites, radio communications, and power grids — the 1859 'Carrington Event' set telegraph equipment sparking.

Some studies, notably from Finland, suggest auroras may occasionally produce faint crackling sounds under rare conditions.

Cultures across the Arctic wove the lights into legend — from spirits playing games in Inuit traditions to omens recorded in Norse and medieval European chronicles.