Think of an ellipse like a slightly squashed circle. This means:
* The Earth's distance from the Sun varies slightly throughout the year. It's closest to the Sun in January (perihelion) and farthest in July (aphelion).
* The Earth's speed also varies slightly. It moves faster when it's closer to the Sun and slower when it's farther away.
While the difference between a circle and an ellipse in the Earth's orbit is relatively small, it's important to remember that orbits are not perfect circles.
