An entire day can pass without sunset in the high latitudes. The phenomenon seems to contradict the daily movement that usually alternates day and night. However, the Earth did not stop: its axis is inclined in relation to the plane of its orbit.
During part of the year, a region close to a pole remains turned towards the light throughout the rotation. The Sun can describe its apparent path without passing below the horizon. At the same season, the other end of the globe is experiencing the opposite situation.
The polar night and the midnight sun are thus the two faces of the same mechanism. Their duration depends on the latitude and the season; not all cities in the north live six identical months by day and six months by night. A simple geometric detail profoundly transforms the way a clock looks and the sky.
What we know
Geometric explanation from an archived educational page; polar day and polar night grouped together, durations not generalized.
To go to the source
References consulted on September 21, 2026. Linked pages may be in another language.
Signaler une erreur ou apporter une précision
