DO ROUND RAINBOWS EXIST?
We’ve all seen a semicircular rainbow. But in rare instances a rainbow is visible as a complete circle. In reality, all rainbows are full circles, but we generally see only the upper half because the rest remains invisible below the horizon. The higher your elevation, the more likely you’ll be able to see a full circle. Relatively recent sightings occurred in 2014 in Saint Petersburg, Russia, and in 2017 in the Bay of Islands in New Zealand. In the first case, construction workers atop a tall crane saw a totally circular rainbow against the sky. In the second instance, a skydiver who had just jumped from a plane caught the rare sight on his camera on the way down.