Aurora Borealis – Nordic Light. | Nordic Light Adventure

Nordic Light which occurs when charged particles (mainly electrons) accelerated to high energies in the Earth’s magnetosphere crash into the Earth’s atmosphere. Such acceleration occurs only in certain regions of the magnetosphere, causing the aurora to occur mainly in ring-shaped areas around the Earth’s two magnetic poles. The aurora takes on various colors and can be yellow-green, green, blue, red, and reddish-violet.[2][3][4] The color of the aurora is determined by the altitude at which the electrons collide with the atmosphere.

(Aurora Borealis at Katterjokk Swedish Lapland in 2023) Normally, the aurora can be seen on almost every clear night at high latitudes under the so-called aurora oval, also called the northern lights oval in the northern hemisphere, and analogously in the southern hemisphere, the southern lights oval. The oval is located as a ring with its center over the magnetic pole. There are actually always auroras in the sky, even during the day, but then it is too bright to be seen with the naked eye.

The auroras are often yellow-green in color, but they can also be completely red or shift to red-violet at the bottom. They can only be seen with the naked eye at night; special instruments are required to observe the phenomenon in daylight. The occurrence of the auroras varies with the activity of the sun and is therefore linked to the so-called sunspot cycle, which is approximately 11 years long. The northern and southern lights also contribute to the high temperatures in the ionosphere, where the auroras occur.

In Sweden, the northern lights oval usually stays approximately above the latitude of Kiruna. Pajala is the place that most often has the aurora within sight. During geomagnetic storms, when the aurora oval is disturbed and grows in size, the aurora can also be seen at more southern latitudes such as central and southern Sweden and in exceptional cases all the way down to Southern Europe or even in Africa. In the same way, the aurora oval expands northwards on such occasions.

Good news for all night owls; the best time to see the Northern Lights is usually between 9:00 PM and 2:00 AM.