During the summer, the North Pole points towards the sun. As a result, there is a period each year when the sun never sinks below the horizon and the sky is light 24 hours a day. This is known as the midnight sun. In Tromsø, the most northerly city in Norway, the midnight sun lasts from 20 May to 22nd July. That’s nearly two whole months without nightfall!
The opposite phenomenon, when the night lasts for more than 24 hours is called polar night, and the sun isn’t seen at all. In Tromsø, this lasts from 27 November to 15 January. Everyday activities, including going to work and school, take place in the semi-dark. Fortunately, moonlight and snow help to brighten the landscape.
Another thing that brightens the dark skies over Norway in the winter, are the northern lights. These are swirling, glowing colours and flickering lights that dance across the night sky. The lights are mostly green and form arcs across the sky, or wispy curtains of travelling light. The northern lights occur when electrically charged particles from the Sun collide with the Earth’s upper atmosphere. These particles get trapped in the Earth’s magnetic field. Here, they collide with other small particles and these small electrical charges create moving bands of light.
People travel from all over the world to see the northern lights. Those who are lucky enough to be looking for them on a very dark and clear night see the lights at their brightest. The lights are at their most frequent in late autumn and winter/early spring.