A nuclear blast could cause a cloud of steam to form that could quickly blanket an area of land.
Scientists say it would take about an hour for a cloud to form on a clear day, and they have no idea how to detect a cloud.
But the clouds could be hard to spot even if they’re in the same spot.
A geoscientist and the director of the Nuclear Detection and Response Center at the U.S. Geological Survey in Boulder, Colo., said the clouds would look like the kind that fall from a tornado.
The clouds could also appear from space, said John Schumann, who is also a geosciences professor at the University of Arizona.
Schumann, whose team recently published its findings on the clouds, said the cloud would likely appear after a flash from a high-velocity nuclear explosion, which is usually about 2,000 feet (610 meters).
Scientists can’t measure the cloud size directly, but Schumann said it would be at least a kilometer (0.6 mile) in diameter.
For the researchers to detect the cloud, Schumann and his team needed a way to get a closer look at the cloud’s height.
They were able to measure it with a radar called a muon spectrometer, which measures the light emitted from the atoms in the air.
The muon is a short-lived element.
It emits light that can travel for thousands of kilometers (miles) in one second.
When the light hits an object, the object emits the muon.
The light travels through the air, and it’s visible to the naked eye.
Schumann said the team measured the height of the cloud in the radar and found it to be about 3,500 feet (1,100 meters).
Schumann and other geoscience researchers believe that a cloud formed as a result of a high speed nuclear explosion.
They’re calling the cloud the Puffball Cloud.
Researchers from the UreAnero Nuclear Laboratory in Portugal said they are working on a muonsighted camera that would capture the cloud and create a digital image that would be able to be tracked and tracked.
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