Why are there seasons?
Are the seasons a result of changes in the distance from the Earth to the sun? No, they are not. In fact, the earth is closest (147 million kilometers) to the sun in January and farthest (153 million km) from the sun in July. There are seasons because the Earth's axis of rotation is tilted 23 degrees, as the diagram below shows. In June, the northern hemisphere is tilted towards the sun. Because of this, the sunlight has a more direct path to the surface. There are also more hours of sunlight during the day. This makes it warmer and it is summer in the northern hemisphere. In the southern hemisphere, the sunlight has a longer path to the surface and the days are shorter in June. It is winter in the southern hemisphere.
The tilt of the also Earth affects when the sun rises!
