What causes the seasons to change?

The change of seasons is fundamentally caused by the tilt of the Earth's axis in relation to the Sun. The Earth is tilted at an angle of approximately 23.5 degrees, which means that as it orbits the Sun throughout the year, different parts of the Earth receive varying amounts of sunlight.

During summer in one hemisphere, that part of the Earth is tilted toward the Sun, resulting in longer days and more direct sunlight, which leads to warmer temperatures. Conversely, during winter, the same hemisphere is tilted away from the Sun, resulting in shorter days and less direct sunlight, causing cooler temperatures.

This axial tilt is the primary reason for seasonal changes, rather than the distance between the Earth and the Sun, which varies throughout the year but does not significantly affect seasonal temperature changes. The rotation of the Earth on its axis creates day and night but does not influence the season's change. The position of the Moon, while it affects tidal patterns, does not play a role in the changing of the seasons. Thus, the tilt of the Earth's axis relative to the Sun is the main driver behind the varying seasons we experience.