Did you know that Earth's orbit around the sun isn't a circle? Instead, it's an ellipse.

[AleksS]

5. For real fun, did you know

That the speed the earth orbits the Sun changes throughout its journey—faster as it’s closer to the sun and slower as it is farther from the sun?

(And bonus: the area of the arc that is swept (think pie slice) is the same for a given amount of time regardless of where in its orbit the earth is; a “fatter” slice is swept when the earth is closer to the sun since it moves faster, and a “skinnier” slice is swept when the earth is farther from the sun since the earth is moving slower!)