This extraordinary image of an apparent floating city has created a stir among conspiracy theorists, but a well-known optical illusion is the likely explanation for the phenomenon.

As reported in the Independent, the bizarre cloud formation appears to show a cityscape high above the city of Foshan in China’s Guangdong province. Footage of the phenomenon appeared on Chinese TV last week and was apparently witnessed by hundreds of astonished onlookers. The sight lasted for only a few minutes before disappearing. A few days later, a similar cloud city was seen in the province of Jiangxi, China.

Conspiracy nutters say it’s evidence of “Project Blue Beam,” a strange plan involving NASA and its attempt to implement a new religion with the Antichrist at the helm.

More reasonably, the phenomenon is likely the Fata Morgana optical illusion, a mirage that happens under special conditions. It happens when rays of light are bent after passing through air layers of varying temperatures in a thermal inversion, i.e. a patch of air in which warmer air resides above cooler air.


Fata Morgana mirages are typically seen just above the horizon, and have caused no shortage of illusions, including castles in the air, inverted and floating boats, twisted mountains, and severely warped atmospheric formations.

Of course, this floating city could also be an elaborate hoax, the product of digital manipulation. The footage of the phenomenon is the only one available, which is hard to believe given that “thousands” of people witnessed it. And though Fata Morgana is a likely explanation, this particular cloud city looks characteristically different than classic Fata Morgana images, which typically appear immediately above the horizon.

More about the Fata Morgana illusion here and here.

Update October 20, 2015: A reader sent me a link with more images. Not sure about the authenticity of these photos, but they’re pretty wild if genuine:


H/t Independent!

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