Do planets have a circular orbit around their star? Like me before stumbling on this fact, many people believed planets have a circular orbit around their star, but this is not true. All planets orbit their neighboring star in an ellipse (oval-shape.) What this means is that it varies how far a planet can be from its star. This is known as an elliptical orbit. When a planet is at its closest point to the Sun, it is known as perihelion. When a planet is at its furthest point from the Sun, it is known as aphelion. So next time you see an image depicting planets in a circular orbit, you will know better!

Since you are reading this fact — the following related fact about Mercury’s orbit is also of interest — read the story.