A horseshoe orbit is like playing tag with someone in a playground. Imagine you're playing tag and you're trying to catch someone who's running around a big tree. You run one direction and the other person runs the opposite direction, but the tree keeps getting in the way, so you keep changing directions. This is what is happening with a horseshoe orbit.
In space, there are objects that orbit the sun, and sometimes they have companions that also orbit the sun. If the objects have enough gravity, they can affect each other's orbits. A horseshoe orbit happens when two objects (like two asteroids) are orbiting the sun, and their gravity pulls on each other in such a way that their orbits start to overlap.
But because their orbits are going in opposite directions around the sun, they end up playing a game of "tag" with each other, and their orbits start to look like a horseshoe. It's called a horseshoe orbit because the shape is similar to the letter "U" or a horseshoe.
In this orbit, the two objects will never collide because they keep changing directions constantly, but they will get very, very close. It's kind of like if you were playing tag with someone and you got really close to them without actually touching them.
Horseshoe orbits are fascinating because they show us how gravity can influence the movements of objects in space. It also helps scientists understand how different objects orbit our sun and each other.