Northern lights - what they are

Updated: Oct 16, 2019

The Northern lights brings thousand of guests to Tromsø each year. As one of the best places in the world to see this spectacle we are fortunate to have both an international size airport, an ice free harbour during the winter, and a lot of roads. Right now we can not seem to have enough places for the guests to sleep - even though most do not sleep much.



The northern lights can be seen, on rare occasions, almost anywhere on earth. In February 1872 , for example, the north lights were seen in Bombay and in Egypt, and in September 1909 they were observed in Singapore and Jakarta! However they belong primarily to the polar regions of the world, occurring most often in a belt around the magnetic pole at a distance of 2,500 km from it. This so-called auroal zone passes over northern Skandinavia, over Iceland and the southern tip of Greenland, through northern Canada, over Alaska and along the northern coast of Siberia.

During the winter time we normally get to see auroras every other day on average, but climate change is making the arctic climate both more wet and milder - e.g. more clouds.

The northern lights originate in a complicated interplay between the so-called solar wind and the earth`s magnetic field, processes that we still know little about. A number of solar wind particles are trapped in the magnetic field and, together with particles which originate in the atmosphere, end up in the tail on the magnetic field on the night side. The spectral lines/colour of the northern lights reflect which gases are found up in the atmosphere - oxygen (green) and nitrogen (red).


Since the northern lights happen far above cloud cover, and is dependent on solar activity it is difficult to predict when and where it will appear. During the winter time we normally get to see auroras every other day on average, but climate change is making the arctic climate both more wet and milder - eg. more clouds.


With the good infrastructure in and around Tromsø we can move around, and we do find clears skies almost every night. Norther lights are best seen between early September until the beginning of April. If you travel even further north to Longyearbyen you get to an are with a period during the winter when the sun is more than 6 degrees under the horizon and you are far north - this means it might be possible to also see daylight auroras.


Want to know how to photograph the northern lights? Read my post https://www.arcticmoments.com/post/how-to-do-northern-lights-photos


Aurora over the Tromsø island a night in Oktober.






Read more about the northern lights at http://geo.phys.uit.no/articl/theaurora.html