nuclear cloud
© CENThe weather phenomenon terrified residents.
This gigantic nuclear explosion-style mushroom cloud looming over a Russian city certainly gave residents a fright.

The bizarre phenomenon was dubbed 'Chernobyl Sky' by shocked residents, in reference to the 1986 nuclear catastrophe in Ukraine.

The frightening but harmless cloud over Tyumen, in south central Russia, was later blown off by the wind.

One social media user wrote: "Chernobyl-style sky... Crazy. Like a nuclear explosion happened there or something. Sky was unreal."

Chernobyl Sky
© CENThe frightening cloud was dubbed 'Chernobyl Sky'

nuclear cloud
© CENIt appeared in the skies above Tyumen, in south central Russia

Another joked: "It'll either rain heavy real bad soon, or USA will drop nuclear bombs on us."

Local meteorologists said the nuclear-style image was simply a natural phenomenon caused by weather conditions causing a column of could to soar nearly 20,000 feet into the sky.

One of the meteorologists - Nina Soldatova - told local media: "There are more than a hundred cloud types and yesterday people saw a cloud that's not really rare."

"It appears when the top part of the cloud spreads out in the sky, and the bottom reaches to the ground.

"Clouds like this can be 16,000 to 19,000 feet tall."
nuclear cloud
© CENOne meteorologist said the cloud formation was not that rare.

The cloud appeared just days after a huge golden UFO was spotted hovering above the earth's atmosphere in NASA footage.

Conspiracy theorists have been chewing over the grainy footage which supposedly shows alien visitors taking an interest in our planet .

This time YouTube user Streetcap1 has uploaded video purportedly taken from the high definition cameras onboard the International Space Station, showing a strange, gold-coloured orb hovering in the clouds above earth.