* Kepler's Laws: Kepler's laws of planetary motion explain this behavior. The most relevant one here is Kepler's Second Law: "A line joining a planet and the Sun sweeps out equal areas during equal intervals of time."
* Conservation of Energy: This means the planet speeds up when it's closer to the Sun and slows down when it's further away. Think of it like a figure skater spinning – they pull their arms in to spin faster, and extend their arms to slow down.
* Elliptical Orbits: Planets don't orbit in perfect circles, but in ellipses. The Sun is at one focus of the ellipse. When the planet is closest to the Sun (perihelion), it's moving fastest. When it's farthest (aphelion), it's moving slowest.
So, in summary:
* Further away from the Sun doesn't necessarily mean slower speed: It depends on the specific point in the orbit.
* A planet's speed is governed by its position in its elliptical orbit. It's fastest at perihelion and slowest at aphelion.
* The overall energy of the planet's orbit remains constant. The speed changes to maintain this constant energy.
