Notice also how much higher in the sky the sun appears in summer than in winter - approximately 47° higher - which is double the angle of the tilt.
Notice how in summer the sun rises in the north east and sets in the north west, and only in March and September does it rise exactly in the east and set exactly in the west. The sun rises earlier and sets later in summer in both hemispheres the further north or south you go because the circles of latitude nearer the poles are exposed to direct sunlight for a longer proportion of the day when the pole in question is facing more towards the sun. This does not mean that everywhere half the time is spent in daylight and the other half in darkness: the distribution of daylight and darkness is complicated by the fact that the earth is tilted on its axis by around 23.5° relative to its orbit around the sun.Īt the height of the European summer, when the northern hemisphere is tilted towards the sun, it experiences more daylight hours than the southern hemisphere which at the same time will be tilted away from the sun.Įxactly six months later the tables are reversed when the southern hemisphere is tilted towards the sun with more daylight hours in the southern hemisphere. More of the Northern Hemisphere is illuminated by the sun in summer - photo courtesy of NASA How the tilt of the earth affects daylight hoursĭue to its spherical nature, at any moment in time half the earth is illuminated by the sun while the other half is in darkness.