Great circle

What Is a Great Circle?

A great circle is a very special kind of circle you can find on round objects, like balls or planets. It is the biggest circle you can draw on the surface of something round, called a sphere. This happens when a flat surface, called a plane, cuts right through the center of the sphere.

Why Are Great Circles Important?

Great circles are super important for traveling long distances on Earth. They show the shortest path between two places on a round surface. Pilots and ship captains often use these paths to save time and fuel on their trips. For example, the equator is a great circle on Earth.

Fun Fact

On a perfect Earth, the equator is a great circle. Any line going from the North Pole to the South Pole and back also makes a great circle. These circles split Earth into two halves. If a great circle passes through one place, it will also pass through the exact opposite point on Earth!