Weird Rainbow... How did it get there?

[travelnow]

Hello Everyone,

I am somewhat new to photography, so this might have a simple and common explanation.

I was out shooting with my D700, AF-S 24-85 G
I took two pictures from virtually the same angle and place, but one of them has part of a rainbow at the bottom left corner, which I didn't notice when I was shooting.

Is it glare from the sun on the lens or do you think it's something else?

 

[fmshoemaker]

Lens flare, they can show up after the most subtle movements. They are in both photos.