Every day, NASA posts an amazing photograph that showcases the wonders of Earth and outer space. Monday’s photograph is like something out of a science fiction movie — an upside down city among golden clouds. The truth behind the photograph is much more mundane, but no less beautiful.

The photo was taken in 2014 by photographer Mark Hersch while aboard a plane that was preparing to land at Chicago’s O’Hare airport. What you’re seeing dangle from the clouds isn’t actually the Windy City — it’s the long shadows of skyscrapers reflecting on a calm Lake Michigan. Another tiny airplane can be seen over the clouds that are covering the real city.

“I am a semi-professional photographer with very expensive equipment yet, ironically, this picture was taken with my iPhone,” Hersch told Inverse, explaining how pretty much everything that led up to him snapping the pic on his iPhone 5 was a total accident.

What’s more, I wasn’t even supposed to be on that flight. I was stuck in Atlanta for a few days during the ice storm a few years ago. This was the first flight I could get back to Chicago. As we made the sweeping turn over Lake Michigan to make the approach to O’Hare, I noticed the unusual scene below. I pulled out my phone, slapped it to the window and made one click. A second later and the scene would have been lost.

Hersch estimated that more than 50 million people have seen his photograph.

“The moral is: be prepared, and always ask for a window seat,” Hersch said.

Photos via Mark Hersch