Meet fata morgana, a complex mirage that can occur when atmosphere conditions are just right. As reported by Wired, this phenomenon is also what has frightened sailors so often, and it just might explain the floating city seen in the video taken in China.

"It has to do with physics and the way our eyes perceive objects around us," wrote TechInsider contributor Rebecca Harrington.

"When we look at something, our brain assumes the light coming from it traveled in a straight line. But this becomes an issue when the light travels through either air or liquid with different densities-when it hits the boundary between the two it bends, sending it off its straight course."

According to People's Daily, China on Twitter, "thousands of residents of Jiangxi and Foshan, China claim they have seen a 'floating city' in the sky." Some are specifically citing NASA as the culprit behind this potential government conspiracy.

Reportedly, this is not the first time a sighting like this has occurred. In June, UFO Sightings Daily reported an alleged UFO seen in Foshan during sunset.

"One thing that is interesting is that this UFO was seen during sunset," wrote founder Scott C. Waring. "Some UFO cloaks are vulnerable during sunset and this causes them to become visible for anywhere between 30 seconds to 15 minutes. Sunset is the most common time of day to see a UFO."

But again, judging by the comment that followed the claim, the phenomenon is mostly likely a lenticular cloud, a completely natural occurrence.