When There's No Ground In The Way, A Rainbow Can Be A Full Circle

Everyone knows how rainbows work: if you go to the end, there's a pot of gold. But what if... the rainbow has no end?

If you weren't on the ground, and were instead in a plane or a very, very tall crane (like this cameraman in the video), there would be enough space to look down and see the rainbow continue - thus the full circle.