The Earth's distance from the Sun changes throughout the year because its orbit is not perfectly circular, but slightly elliptical. Here's a breakdown:

* Average distance: The average distance between the Earth and Sun is about 93 million miles (150 million kilometers). This is also known as one Astronomical Unit (AU).

* Perihelion (closest): The Earth is closest to the Sun in early January, at a distance of about 91.4 million miles (147.1 million kilometers).

* Aphelion (farthest): The Earth is farthest from the Sun in early July, at a distance of about 94.5 million miles (152.1 million kilometers).

Therefore, the Earth-Sun distance changes by about 3.1 million miles (5 million kilometers) between its closest and farthest points in orbit.

This difference in distance does not significantly impact the Earth's seasons. Seasons are caused by the tilt of the Earth's axis, not the change in distance from the Sun.