This isn't about radio or TV - because neither existed when this happened. It's the remarkable story about three obsessed researchers who found the first photograph ever taken of two human beings. It traces back to 1838, when photography pioneer Louis Daguerre took an experimental photo of a man having his shoes shined somewhere in Paris. 

It's since been determined that was first photo of a human being to ever appear on film. But where, exactly, did it happen? Despite the passage of centuries and a very changing landscape, the trio was determined to find out.   

"Though the street was a bustling thoroughfare, the photograph shows only these two figures. Why? No one else stood still long enough to be captured by Daguerre’s long-exposure camera, which took up to ten minutes."

The story below outlines their U2-like moment, where they finally found what they've been looking for. You can see the famous photo below. 

Where Exactly Were the First Humans to Be Captured in a Photograph Standing? Three Obsessed Filmmakers Solved the Nearly 200-Year-Old Mystery