Rainbows aren't just arcs in the sky - they're actually full circles

Rainbows are one of nature's most stunning displays. They form when light enters and bends out of raindrops in the air. The conditions have to be perfect in order for you to see the rainbow. However, all rainbows are actually full circles. They can only be seen by humans if we're in the air because, from Earth's surface, the ground interferes.