Size in mm: 144 x 70. Upgraded in 2002 with a hologram, foil stripe. Notes with annual figures from 2009 (printed abroad) have a letter in front of the serial number.

Obverse

The motif on the obverse of the note is a portrait of Kristian Birkeland. The northern lights rising upwards toward the North Star are the central feature of the background.

We also find well-known constellations such as Little Bear (Ursa Minor) and the Big Dipper.

Birkeland's "Terrella" where he produced artificial northern lights is depicted in the area containing the watermarks. Birkeland demonstrated that when plasma escapes from the sun and travels through space, the earth's magnetic field compresses it on the daylight side of the earth and stretches it into a tail on the night side, ultimately producing the northern lights.

The snow crystal symbolises winter, the time of year when the northern lights are most visible, and includes a number of security features.

Reverse

The reverse side of the note is based on the northern lights that are visible during the day. Whereas the northern lights on our side of the earth are visible along the coast of northern Norway at night, they are visible over Svalbard, a Norwegian archipelago in the Arctic Ocean, during the day.

Discovery of the auroral oval and the northern lights on the day side of the earth is one of the most sensational results of modern space research.

The illustrations in the lower right hand corner of the note depict Birkeland's thoughts about the orientation of electric currents in connection with the northern lights. Currents near the auroral arcs flow parallel to the ground, while those that are higher up flow along the earth's magnetic field lines. These currents are called Birkeland Currents.