Lindsay Hughes asks: "I was flying into Knoxville and this glowing rainbow orb was flying along with us above the clouds. What is it?" She also sent along a picture of what she saw.
Great question Lindsay! What you saw is commonly called a "glory" or a "pilot's rainbow".
It's basically a rainbow-like circle around the shadow of an airplane on a layer of clouds below.
We took the picture to local pilot Jim Roberts. He's been flying planes for more than four decades-- everything from single engines to jumbo jets.
He told us glories are somewhat common, and are caused by an interaction between sunlight and tiny water droplets that make up a cloud. Here's what's fascinating: When pilots see glories, we see the same thing, only it looks like a traditional rainbow to us.
"Well if you're on the ground, and you're looking at a rainbow, you see half the circle because the horizon blocks out the bottom half of the circle. When you're in the air, you see the complete circle. The sun has to be behind you, and you're looking in the same direction as the sun's rays as they hit the moisture in the atmosphere and basically makes a circular rainbow," said Roberts.
Roberts also says he's seen some pretty crazy stuff during his time in the sky. He says the wildest was when he saw the Northern Lights going across the North Atlantic in the middle of the night. He says it looked like the beams of light just wrapped around the cockpit and the aircraft!