Here's why:
* Eccentricity: A measure of how much an orbit deviates from a perfect circle. A value of 0 represents a perfect circle, while a value of 1 represents a highly elongated ellipse.
* Mercury's Eccentricity: Mercury's eccentricity is about 0.206, which is significantly higher than other planets. This means its orbit is quite elongated.
This high eccentricity causes Mercury's distance from the Sun to vary significantly throughout its orbit.
