What the Northern Lights Look Like

VISUAL 3 (movie): Aurora Drawing—optional Along with the Auroral Storm Narration video (below), play the video that will be used later for the aurora drawing activity. Use playback controls—pause, play, fade off/on, turn volume off/on. [Fade off Aurora Drawing]

Those who stay up late during the dark time of year above the arctic circle may witness the aurora borealis, a spectacular display of light. Let us watch and listen as a Norwegian from Tromsø (named Franck Pettersen), who has photographed the northern lights, describes the event

VISUAL 4 (movie): Auroral Storm with Narration
[Play the video of the aurora being narrated by Norwegian Franck Pettersen.]

Text of the Narration

Then a faint light low in the northwest draws an attention. It is just above the mountains and is like a green phosphorescent band. It just sits there, or moves very slowly. It dies out. But if you are used to northern lights, you know that this was not the end. This was just the beginning. 

Half an hour later, a new band appears. This time it moves from northwest, where we first saw it, higher up in the sky. It curls, and the curl floats along the band from west to east like a wave. A new band is lit in the north west and moves upward, and another band. Waves and curls are moving along the bands. You can see they are composed of rays as the bands are getting broader. Is there a red color there too? The light is getting stronger and you can see only the brightest stars through the bands and arches of the northern lights. 

Then, within a few minutes the sky seems to explode. There is a dramatic change in the events up there. An auroral substorm has started. Rays of light shoot down rapidly, forming bands like draperies which spread all over the sky. And they really remind us of draperies or curtains which are flickering in the wind. The curtains are still green, but now they are decorated with a violet and a red trimming at the lower and upper ends. The draperies and bands are moving and undulating vigorously all over the sky, disappearing and forming all over again by new rays shooting down from space. Above our heads we can see rays going out in all directions forming what is called an auroral corona. This is the peak in the show that nature has set up for us, caused by a cosmic magnetic field and the solar wind. In this crescendo the corona dies out and new coronas can form. The mountains in the setting are now illuminated by the light and energy from space. 

After ten to twenty minutes the activity decreases again. The substorm is over. The bands are spread out, getting weaker, and are finally dissolved in a diffuse light all over the sky. We cannot see any more bands or arches, but we discover that the sky background looks grayish-green, and we can’t see very many stars. The light reaching us from all directions is so strong that we can easily see details around us, even far away from the city or other light sources. And if we observe the sky carefully, we can see the last part of the Northern lights display like clouds being switched on and off as though by an electric light switch every five to ten seconds. It is now between twelve and two o’clock in the morning, and the play is over.

Fade off the Aurora movie.