Final answer:
The seasons are caused by the 23.5° tilt of Earth's axis, not by the distance between Earth and the Sun. This axial tilt results in varying sunlight angles and day lengths throughout the year, creating seasonal changes.
Step-by-step explanation:
What Causes the Seasons?
The cause of the seasons is not the varying distance between Earth and the Sun, as Earth's orbit causes only a minor change in that distance. Instead, the seasons are due to the 23.5° tilt of Earth's axis of rotation. During different times of the year, this tilt causes different parts of Earth to receive varying amounts of sunlight. For example, at the summer solstice, the Northern Hemisphere is tilted toward the Sun, resulting in longer days, higher sun angles, and more intense sunlight, leading to warmer temperatures. In contrast, during the winter solstice, the Northern Hemisphere is tilted away from the Sun, leading to shorter days, lower sun angles, and less intense sunlight, thus cooler temperatures. The equinoxes mark the times of the year when the tilt is neither away from nor towards the Sun, resulting in approximately equal hours of day and night. These seasonal variations in sunlight and heat are different at different latitudes and are the primary cause of the different seasons experienced on Earth.